BACKGROUND

The U.S. Department of Agriculture (USDA), through its Agricultural Marketing Service (AMS), purchases and distributes food for the federal food and nutrition programs. One of those programs is the National School Lunch Program (NSLP), which has been receiving ground beef purchased by AMS for more than 60 years. The AMS ground beef purchase program, which is referred to as the Federal Purchase Ground Beef Program, also provides ground beef and other commodities to food banks, emergency feeding programs, Indian reservations, programs that serve the elderly, disaster relief agencies, and a variety of other institutions. Thus, although the NSLP is a primary beneficiary of the Federal Purchase Ground Beef Program, the program serves many of the most vulnerable Americans of all ages and backgrounds.

AMS buys ground beef from more than 15 suppliers that are required to comply with federal regulations and guidelines and to adhere to strict nutritional, food safety, and food quality requirements. Specifications for the Federal Purchase Ground Beef Program exceed those mandated by the USDA Food Safety and Inspection Service (FSIS) for all federally inspected meat processing plants. Since 2003, more than 15 companies have participated constantly in the program. The number of companies that supply ground beef varies from time to time because of changes in eligibility status.

In the late 1990s, the AMS specifications for ground beef and boneless beef were spelled out in Technical Data Supplement 136 (TDS-136). TDS-136 required that suppliers meet FSIS regulatory requirements for sanitation and Hazard Analysis and Critical Control Point (HACCP) plans, have one antimicrobial intervention step that is a critical control point in their HACCP plans, and comply with FSIS good manufacturing practices. In 2001–2002, requirements were added to the TDS-136 specifications; among these were having one additional antimicrobial intervention step, testing carcasses for E. coli O157:H7, and having a quality control program that meets the microbiological upper specification limits for indicator microorganisms (for grinders that perform extra trimming).

In 2003, the first Technical Requirements Schedule for ground beef (TRS-GB) was implemented, and suppliers were required to submit a technical proposal. According to the TRS-GB, which supersedes TDS-136, AMS would buy ground beef only from suppliers that successfully document their process (by submitting a technical proposal) and undergo an on-site assessment that ensures that all AMS specifications are met before any contract award. The TRS-GB required a contracted supplier to use statistical process control methods (statistical techniques for monitoring and controlling a process to ensure that it is able to produce a conforming product) and to test for Salmonella and E. coli O157:H7 (in raw materials and finished ground products). Samples that tested positive for Salmonella or E. coli O157:H7 would be rejected by AMS, and the supplier in question would be required to conduct a cause–effect analysis to prevent recurrence. Processors that have numerous instances of positive results for those organisms would be deemed ineligible to contract with the Federal Purchase Ground Beef Program. In 2004, AMS established contracts with outside laboratories to perform microbial testing on all suppliers’ samples.

In December 2009, a news report in USA Today suggested that some large-scale purchasers of ground beef in the corporate sector have more stringent requirements for their suppliers than does USDA. That and other articles and a letter from U.S. Senator Kirsten Gillibrand (D-NY) to Secretary of Agriculture Tom Vilsack about perceived deficiencies in the Federal Purchase Ground Beef Program, led to a technical review of the AMS ground beef purchase standards by the USDA Agricultural Research Service (ARS) and FSIS concurrent with the USDA Office of the Inspector General (OIG) audit that was being conducted at that time.

AMS also held discussions with large commercial beef suppliers and purchasers to learn about their food safety approaches and to hear their comments on the July 2010 TRS-GB. In February 2010, USDA announced new food safety initiatives, which included revision of the AMS TRS-GB based on new recommendations from ARS, FSIS and OIG. The announcement of the new initiatives was followed in



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BACKGROUND The U.S. Department of Agriculture (USDA), through its Agricultural Marketing Service (AMS), purchases and distributes food for the federal food and nutrition programs. One of those programs is the National School Lunch Program (NSLP), which has been receiving ground beef purchased by AMS for more than 60 years. The AMS ground beef purchase program, which is referred to as the Federal Purchase Ground Beef Program, also provides ground beef and other commodities to food banks, emergency feeding programs, Indian reservations, programs that serve the elderly, disaster relief agencies, and a variety of other institutions. Thus, although the NSLP is a primary beneficiary of the Federal Purchase Ground Beef Program, the program serves many of the most vulnerable Americans of all ages and backgrounds. AMS buys ground beef from more than 15 suppliers that are required to comply with federal regulations and guidelines and to adhere to strict nutritional, food safety, and food quality requirements. Specifications for the Federal Purchase Ground Beef Program exceed those mandated by the USDA Food Safety and Inspection Service (FSIS) for all federally inspected meat processing plants. Since 2003, more than 15 companies have participated constantly in the program. The number of companies that supply ground beef varies from time to time because of changes in eligibility status. In the late 1990s, the AMS specifications for ground beef and boneless beef were spelled out in Technical Data Supplement 136 (TDS-136). TDS-136 required that suppliers meet FSIS regulatory requirements for sanitation and Hazard Analysis and Critical Control Point (HACCP) plans, have one antimicrobial intervention step that is a critical control point in their HACCP plans, and comply with FSIS good manufacturing practices. In 2001–2002, requirements were added to the TDS-136 specifications; among these were having one additional antimicrobial intervention step, testing carcasses for E. coli O157:H7, and having a quality control program that meets the microbiological upper specification limits for indicator microorganisms (for grinders that perform extra trimming). In 2003, the first Technical Requirements Schedule for ground beef (TRS-GB) was implemented, and suppliers were required to submit a technical proposal. According to the TRS-GB, which supersedes TDS-136, AMS would buy ground beef only from suppliers that successfully document their process (by submitting a technical proposal) and undergo an on-site assessment that ensures that all AMS specifications are met before any contract award. The TRS-GB required a contracted supplier to use statistical process control methods (statistical techniques for monitoring and controlling a process to ensure that it is able to produce a conforming product) and to test for Salmonella and E. coli O157:H7 (in raw materials and finished ground products). Samples that tested positive for Salmonella or E. coli O157:H7 would be rejected by AMS, and the supplier in question would be required to conduct a cause– effect analysis to prevent recurrence. Processors that have numerous instances of positive results for those organisms would be deemed ineligible to contract with the Federal Purchase Ground Beef Program. In 2004, AMS established contracts with outside laboratories to perform microbial testing on all suppliers’ samples. In December 2009, a news report in USA Today suggested that some large-scale purchasers of ground beef in the corporate sector have more stringent requirements for their suppliers than does USDA. That and other articles and a letter from U.S. Senator Kirsten Gillibrand (D-NY) to Secretary of Agriculture Tom Vilsack about perceived deficiencies in the Federal Purchase Ground Beef Program, led to a technical review of the AMS ground beef purchase standards by the USDA Agricultural Research Service (ARS) and FSIS concurrent with the USDA Office of the Inspector General (OIG) audit that was being conducted at that time. AMS also held discussions with large commercial beef suppliers and purchasers to learn about their food safety approaches and to hear their comments on the July 2010 TRS-GB. In February 2010, USDA announced new food safety initiatives, which included revision of the AMS TRS-GB based on new recommendations from ARS, FSIS and OIG. The announcement of the new initiatives was followed in 7

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program April 2010 by a request from USDA for an assessment of the AMS ground beef safety requirements by an independent body. The National Research Council was asked to perform the assessment and to provide a report to AMS and FSIS. COMMITTEE’S STUDY APPROACH The committee’s statement of task is as follows: An NRC-appointed committee will evaluate the scientific basis of current food safety requirements of the Federal Purchase Ground Beef Program and prepare a letter report of its findings. In the course of its study, the committee will examine technical and other documents that describe food safety measures required of suppliers of ground beef to the Program. Such measures include food safety requirements in the process of manufacturing ground beef items and the testing of materials (including laboratory accreditation and procedures established by those laboratories for selection, delivery, analysis, and reporting of findings of samples) throughout the process, from slaughter to delivery of product to the recipient. The study will also examine how USDA standards, methods, and requirements compare to those used in the large purchasing programs of industry leaders who supply ground beef products directly to the consumer through retail sales or food service operations. The committee will seek input from suppliers, food safety experts, and other entities involved in purchasing ground beef on a large scale. The committee's report will present the committee's evaluation of the scientific validity of USDA's current technical requirements and methods and a benchmark of USDA processes and methods relative to those in recognized industry-leader programs. The report will also provide recommendations to USDA on how to perform future periodic evaluations relative to recognized best practices. On the basis of the statement of task, the committee considered the following as its charge: to evaluate the scientific basis of the AMS technical documents that describe food safety requirements for suppliers to the Federal Purchase Ground Beef Program and procedures for testing laboratories, to examine how the AMS standards, methods, and requirements compare with those used in large purchasing programs of industry leaders that supply ground beef products directly to consumers through retail sales or food service operations, and to provide recommendations to AMS for conducting periodic evaluations of the Federal Purchase Ground Beef Program. The committee examined the scientific basis of the AMS July 2010 TRS-GB (USDA-AMS, 2010a) and of the June 2010 Statement of Work (SOW) for AMS-accredited laboratories (USDA-AMS, 2010b), and it considered ARS and FSIS representatives’ answers to questions posed by the committee during its second meeting. To address the second task, the committee requested, through a representative of an industry association (Scott Goltry, American Meat Institute), microbiological specifications for retail and commercial food service entities that purchase ground beef directly from meat companies or indirectly from purchasers or suppliers. The committee used the combined knowledge that it gained in addressing the first and second tasks and its own collective expertise and judgment to address the third task—to provide recommendations to AMS for evaluating its program. 8

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program THE SCIENTIFIC BASIS OF THE AGRICULTURAL MARKETING SERVICEFEDERAL PURCHASE GROUND BEEF PROGRAM SPECIFICATIONS To address the scientific basis of the AMS ground beef purchase specifications, the committee evaluated and considered the following:  Data available on Salmonella and E. coli O157:H7 outbreaks associated with beef in schools.  Recognized principles for establishment of microbiological criteria.  Indicator microorganisms as potential predictors of food safety.  AMS specific requirements.  Statistical process capability.  The June 2010 Statement of Work for AMS-accredited laboratories. Outbreaks Associated with Ground Beef in Schools The AMS purchase specifications for frozen ground beef include criteria for the pathogens Salmonella and E. coli O157:H7, which are recognized hazards in raw ground beef products (ICMSF, 2005). To assess the extent of the risk to schoolchildren posed by the presence of the pathogens in AMS purchased ground beef, the committee reviewed foodborne-illness outbreaks in schools associated with ground beef and products containing ground beef. An outbreak is defined as the development of a similar illness in two or more persons after consumption of the same food (CDC, 2010a). The Centers for Disease Control and Prevention (CDC) coordinates national surveillance of foodborne diseases in the United States. Although responsibility for foodborne-disease surveillance and outbreak investigation resides in the jurisdictions of local and state health departments, information about confirmed and suspected foodborne outbreaks is reported to CDC. Since 1998, CDC has collected a standardized set of data on each reported outbreak that include state, date, and location of occurrence; etiology; numbers of ill, hospitalized, and deaths; and associated food (vehicle) if identified (CDC, 2010b). Most cases of foodborne illness do not occur as parts of recognized outbreaks, but information from outbreak investigations is extremely important in determining the safety of specific food items or commodities. That is particularly true for school settings, where large groups of students may be exposed to a contaminated food item simultaneously. Clustering of cases in a school makes it more likely that a common source of exposure would be recognized than if a similar food item were distributed through grocery stores or restaurants. Furthermore, school-aged children are more likely to be medically evaluated for illnesses involving bloody diarrhea or fever. Thus, outbreak data constitute a useful tool for evaluating the risk of E. coli O157:H7 and Salmonella associated with ground beef in schools. From 1998 to 2007, 492 confirmed foodborne-disease outbreaks in schools were reported to CDC. The number of reported outbreaks per year ranged from 31 in 2007 to 70 in 2000. Norovirus accounted for 164 (33%) outbreaks; 160 (33%) had an unknown etiology, but many of these were probably due to norovirus. The number of school-associated outbreaks has been declining since the publication of a U.S. General Accounting Office report that was published in 2000 (GAO, 2000). Information on school outbreaks due to E. coli O157:H7 and Salmonella are summarized below. E. coli O157:H7 From 1998 to 2007, CDC received reports of 263 confirmed foodborne outbreaks of E. coli O157:H7 infection in the United States. Ground beef (or products containing ground beef, such as 9

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program meatballs, lasagna, and tacos) was identified as a vehicle in 69 (26%) of the outbreaks. Schools were identified as a location of three of the ground beef outbreaks—two in 2000 and one in 2003. An additional outbreak of E. coli O157:H7 infection associated with a school lunch in Washington state occurred in 1998 but was not so identified in the CDC database. Hence, a total of four ground beef outbreaks in schools have been reported in the United States since 1998. One of the 2000 outbreaks occurred in a private elementary school in Minnesota, and the other occurred at the State University of New York (SUNY), Albany. The 2003 outbreak involved beef burritos that were distributed in restaurants and schools in Nebraska. Because the Federal Purchase Ground Beef Program supports food assistance programs, such as the NSLP, the committee thought it unlikely that the 2000 SUNY outbreak and the 2003 restaurant–schools outbreak involved AMS-purchased ground beef and therefore did not consider them relevant to the discussion of the safety of ground beef in the Federal Purchase Ground Beef Program. Thus, from 1998 to 2007 there were two primary school lunch outbreaks associated with ground beef contaminated by E. coli O157:H7 that may have involved ground beef purchased by AMS (S. A. Seys, Office of Public Health Science, FSIS, USDA, Minneapolis, MN, personal communication, Aug. 2, 2010). In the 1998 Washington state outbreak, students in Finley Elementary School became ill after eating apparently undercooked ground beef in tacos prepared in the school. About 3% of children who ate the tacos became ill, and the odds ratio of 4.2 had a very wide 95% confidence interval (0.4–108.2), which may have affected how information about the outbreak was entered into the CDC database. The ground beef was obtained through the NSLP, and this was the only outbreak confirmed and linked to the Federal Purchase Ground Beef Program. At least 11 children became infected. The outbreak led to a $4.6 million award as a result of litigation (GAO, 2003). In the 2000 Minnesota outbreak, at least 18 students (11% of those interviewed) in a Catholic grade school in Minneapolis became ill after eating apparently undercooked ground beef in a baked casserole (called hot dish) prepared in the school. A review of ground beef handling procedures in the school indicated that thawing, cooking, and cooling of the ground beef may have been inadequate. However, the plant of origin and the packing date of the ground beef used in the hot dish could not be conclusively identified. Both those outbreaks occurred before FSIS issued the October 7, 2002, Federal Register notice (USDA-FSIS, 2002) that required establishments to “reassess their HACCP plans to determine whether E. coli O157:H7 contamination is a hazard reasonably likely to occur in their production process”. Successful implementation of HACCP plans throughout the beef industry has been widely credited with improving the quality and safety of ground beef. From 1998 to 2000, a mean of 9.0 ground beef– associated outbreaks of E. coli O157:H7 infection occurred each year. From 2001 to 2004, only 4.8 ground beef–associated outbreaks per year were reported. From 2005 to 2007, a mean of 7.7 outbreaks per year were reported, and 12 were reported in 2007. However, no additional school lunch–associated outbreaks were associated with ground beef after the reassessment was required. Those results suggest that when E. coli O157:H7 control practices are not followed, outbreaks can occur. However, such outbreaks appear to be uncommon; one confirmed outbreak was attributed to AMS-purchased ground beef in a 10-year period. Both adherence to proper food handling practices and the low likelihood of ground beef contamination (about 0.13% according to data provided by AMS) contribute to the primary prevention of school-associated outbreaks. However, the relative importance of adherence to the practices and the low likelihood of contamination has not been determined. Salmonella From 1998 to 2007, CDC received reports of 1,152 confirmed outbreaks of foodborne Salmonella infection. Ground beef (or products containing ground beef, such as meatballs, lasagna, and tacos) was identified as a vehicle in 36 (3.1%) of the outbreaks. A school was identified as a location of only one of the outbreaks, which was associated with beef lasagna that was prepared at home and eaten in a school. 10

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program The CDC database indicates that the key ingredient in the lasagna that contributed to the outbreak was eggs, and ground beef was not the likely source of the Salmonella Enteritidis contamination. Hence, no confirmed Salmonella outbreaks in schools during 1998–2007 were associated with ground beef obtained through the Federal Purchase Ground Beef Program or any other source. Principles for Establishing Microbiological Criteria Internationally recognized bodies—such as the National Research Council (NRC, 1985), the Institute of Medicine (IOM,2009), the International Commission on Microbiological Specifications for Foods (ICMSF,2002), and the Codex Alimentarius Commission (CAC,1997)—have developed principles and procedures based on scientific knowledge, statistical rules, and epidemiological information to determine when establishment of microbiological criteria and testing should be expected to make a contribution to public health. They all emphasize the use of a systematic approach for process control, such as HACCP, as the primary and most effective means of managing microbial hazards to protect public health. They also point out that appropriate microbiological testing can serve a useful role in assessing the adequacy of food safety programs. However, no matter how extensive it might be, microbiological testing alone cannot ensure the safety of the food supply. Following the principles outlined by the National Research Council, ICMSF, and CAC would provide a more transparent and systematic process that is based on scientific principles for establishing specifications. The National Research Council has discussed the role of microbiological criteria for foods in a detailed report (NRC, 1985). The more recent general principles described by CAC (1997) are consistent with the 1985 National Research Council conclusions. The CAC (1997) principles are used as an example in this report because they are more recently published and internationally recognized principles that have been fully vetted through CAC and are cited as the guiding principles for establishment of microbiological criteria by other authoritative groups (for example, ICMSF, 2002).The CAC principles are intended to apply to both regulatory authorities and food business operators. Some sections of the principles are particularly relevant to the present discussion in that they address basic guidelines for developing criteria and potential actions that can be taken when criteria are not met. Some portions of Principles for the Establishment and Application of Microbiological Criteria for Foods that are useful for AMS to consider are discussed below with examples of how they may apply to the Federal Purchase Ground Beef Program. Application of Appropriate Tests CAC/GL 21-1997 Section 2.3: When applying a microbiological criterion for assessing products, it is essential, in order to make the best use of money and manpower, that only appropriate tests be applied to those foods and at those points in the food chain that offer maximum benefit in providing the consumer with a food that is safe and suitable for consumption. On the basis of scientific principles, the National Research Council (NRC, 1985, p. 3) reached a similar conclusion and stated that “microbiological criteria should be established and implemented only when there is a need and when the criterion can be shown to be effective and practical”. Public or social considerations may also attempt to influence development of criteria; however, the present committee concurs in the previous conclusions (NRC, 1985; CAC, 1997) that resources should be applied to science- based criteria. 11

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program One example of a test that may not be scientifically appropriate in the Federal Purchase Ground Beef Program is the one for Staphylococcus aureus. The rationale follows, using information from ICMSF (1996, 2005) as supporting evidence. S. aureus is naturally associated with mucous membranes and skin of warm-blooded animals, so its presence does not necessarily indicate inappropriate conditions in raw product. The minimum and optimum temperatures for growth are 7°C and 37°C (45°F and 99°F), respectively; and the minimum and optimum temperatures for toxin production are 10°C and 40–45°C (50°F and 104–113°F), respectively, under otherwise optimum conditions. Growth and toxin production are inhibited by the presence of other microorganisms. Inasmuch as toxin production requires a S. aureus population of at least 106colony forming units (CFU) per gram (ICMSF, 2005, p. 35), which is ten times greater than the AMS upper specification limit (USL)2 for aerobic plate count (APC, a method of determining the total number of aerobic bacteria in food), this hazard is not likely to occur. The low temperatures (below 7°C) used for ground beef processing also inhibit S. aureus growth. Some may consider S. aureus as an indicator of process control, but other measures—such as APC, coliforms, and E. coli—serve the same purpose. The APC may also be a more useful indicator because the diversity of the population present may include organisms that have higher growth rates at lower temperature. Documentation of analysis in a manner similar to that conducted for S. aureus would provide AMS with transparent justification of how science and principles for establishing criteria were applied in the establishment of other microbiological criteria. AMS provided no such documentation for the present committee to review; if such analysis is conducted, changes in other criteria may be justified. Recommendations related to Salmonella are also discussed below in Finding A5. Finding A1: The committee finds no scientific basis for including S. aureus criterion in the AMS purchase specifications. It does not present a public health issue in this product, its presence does not indicate inappropriate handling or conditions, and other tests provide more useful information on process control. Testing for S. aureus does not add value. Recommendation A1: The committee recommends that the criterion for S. aureus be removed from the Federal Purchase Ground Beef Program and that similar analyses be conducted and documented for other criteria to provide transparency and a scientific basis for the criteria specified. Dependence of Appropriateness of Criteria on Intended Use CAC/GL 21-1997 Section 3.1.1 Application by regulatory authorities, paragraph 3: In situations of non-compliance with microbiological criteria, depending on the assessment of the risk to the consumer, the point in the food chain and the product-type specified, the regulatory control actions may be sorting, reprocessing, rejection or destruction of product, and/or further investigation to determine appropriate actions to be taken. The National Research Council (NRC, 1985, pp. 27–28) reached a similar conclusion for both regulators and processors. The present committee concurs in the previous conclusions of the National Research Council and CAC. AMS excludes noncompliant raw ground beef products from all USDA food and nutrition programs. The committee concludes that the AMS criteria for pathogens are not relevant for product that is intended to be fully cooked, especially when it is under such controls as those in a USDA- inspected establishment. For example, if a sample of a lot of ground beef trim tests positive for E. coli O157:H7, the lot is classified as containing the pathogen. The meat processor cannot use the lot to manufacture uncooked ground beef patties. However, under FSIS regulations, the meat processor can ship 2 Expressed as CFU/g for each indicator organism; USL is factored into the determination of a supplier's process capability or capability to supply a product that conforms to AMS specifications. 12

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program the product to a further processor, and the further processor can use the trim in a product that will be cooked. The cooking process must be sufficient to destroy E. coli O157:H7. After cooking, the meat product is considered to be safe to eat. There is substantial scientific justification for stating that validated cooking processes provide greater assurance of safety than testing (for example, ICMSF, 2002). In light of statistical implications associated with sampling plans, testing cannot guarantee the absence of pathogens (ICMSF, 2002). In addition, slight deviations above the concentrations of microbial indicators specified in the July 2010 TRS-GB (USDA-AMS, 2010a) do not necessarily indicate the unwholesomeness of product (that is, that it is not fit for consumption and is possibly injurious to health) (see the next section of this report, on indicator microorganisms). That is not to suggest that grossly contaminated product (that is, having substantially more contamination than should be present if good manufacturing practices are applied) or spoiled product should be accepted for further processing. Finding A2: The current AMS testing requirements apply to ground beef that may be used in a variety of forms, including frozen ground beef patties (which are likely to be cooked in that state by the end user), coarse ground beef (which AMS indicated is likely to be fully cooked in a USDA-inspected facility), and other products, such as products that are irradiated. Application of the same criteria for all applications is not consistent with Codex Principle CAC/GL 21-1997 Section 2.3. When the ultimate use of a product cannot be determined, it is reasonable to use conservative specifications. However, during a public meeting with AMS on July 15, 2010, the committee learned that for some products, such as coarse ground beef, further processing in USDA-inspected facilities is expected. Recommendation A2: The committee recommends that AMS consider conducting a more thorough review of criteria for different product types through a national advisory committee designated to provide impartial scientific advice on microbiological criteria to federal food safety agencies, such as the National Advisory Committee on Microbiological Criteria for Food (NACMCF). The representation of academic, industry, and government experience on NACMCF, or a similar group, can provide a balanced study of specific science-based applications. Considerable time and relevant data are necessary to provide a thorough analysis of the specific criteria recommended for different applications. Some criteria may not be relevant for products intended to be fully cooked in USDA-inspected facilities. Finding A3: There is no public health benefit of removing all noncompliant products from all other AMS programs if they are to be cooked later according to FSIS guidelines in a USDA-inspected facility. However, indications of unwholesomeness are always grounds for rejection of product. Recommendation A3: The committee recommends that AMS consider permitting July 2010 TRS-GB noncompliant products to be used in cooked meat products purchased through USDA food and nutrition programs if they meet FSIS requirements. Identification of Appropriate and Technically Feasible Criteria to Protect Public Health CAC/GL 21-1997 Section 4 General Considerations Concerning Principles for Establishing and Applying Microbiological Criteria: 4.1 A microbiological criterion should be established and applied only where there is a definite need and where its application is practical. Such need is demonstrated, for example, by epidemiological evidence that the food under consideration may represent a public health risk and that a criterion is meaningful for consumer protection, or as the result of a risk assessment. The criterion should be technically attainable by applying Good Manufacturing Practices CAC/GL 21 (Codes of Practice). 4.2 To fulfill the purposes of a microbiological criterion, consideration should be given to:  the evidence of actual or potential hazards to health;  the microbiological status of the raw material(s); 13

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program  the effect of processing on the microbiological status of the food;  the likelihood and consequences of microbial contamination and/or growth during subsequent handling;  storage and use;  the category/categories of consumers concerned;  the cost/benefit ratio associated with the application of the criterion; and  the intended use of the food. The National Research Council (NRC, 1985, p. 17) identified similar considerations for foods for which criteria are appropriate, and the present committee concurs in the previous conclusions of the National Research Council and CAC. AMS has identified the most relevant pathogens for raw ground beef—Salmonella and E. coli O157:H7—and efforts to minimize such contamination are appropriate. AMS has also taken a precautionary approach to establishing criteria for frozen ground beef and assumes that all products they consider for purchase will not be further processed. As previously discussed, that is not the case: AMS indicates that as much as 80% of the product will be fully cooked in a USDA- inspected establishment. Furthermore, the committee’s analysis of outbreaks associated with ground beef in schools suggests that outbreaks were rare even before the AMS and FSIS requirements became more stringent. That suggests that controls in place before AMS modified its requirements were appropriate for protecting public health. Furthermore, current FSIS Performance Standards for ground beef (9 CFR 310.25) consider Salmonella as an indicator and therefore allow its presence in up to 7.5% of samples collected in an establishment, an acknowledgment that it is not feasible to eliminate the pathogen in raw ground beef. Therefore, the AMS standard for ground beef free of Salmonella is inconsistent with recognized principles for establishment of specifications. Finding A4: The application of more stringent microbiological criteria by AMS for the 2010 Federal Purchase Ground Beef Program is inconsistent with CAC/GL 21-1997 principle 4 in that previous requirements appeared adequate to protect public health. Recommendation A4: As previously recommended, AMS should consider conducting a more thorough review of criteria for different product types through existing national advisory committees or organizations. Finding A5: FSIS policies acknowledge that Salmonella may be present in raw frozen ground beef that is produced under the Food and Drug Administration’s Good Manufacturing Practices. Cooking requirements for both food processing (in USDA-inspected facilities) and food service (state and local food-code requirements) are designed to eliminate that hazard, and procedures to control cross- contamination are mandated in both settings. Frozen storage and distribution do not allow growth of the organism. Thus, the AMS-implied zero tolerance for Salmonella (actually, absence in 25 g) is inconsistent with established principles for developing microbiological criteria and with current FSIS requirements. The committee emphasizes that a standard that requires the absence of a pathogen in some quantity of food is not actually a true zero tolerance. For example, a sampling plan that requires testing of only a single 25-g sample of food has a 63% chance of accepting a lot that contains Salmonella at a concentration of 1 CFU/100g, with a standard deviation of 1 log CFU/g (which means that the concentration varies from 1 CFU/1,000 g to 1 CFU/10 g). A sampling plan that reduces the chance of accepting that same lot to less than 5% requires at least seven negative samples of 25 g each (ICMSF, 2009). Recommendation A5: AMS should consider using Salmonella as an indicator in a manner similar to FSIS. One approach is a moving window, in which results are evaluated over time and old results are eliminated as new results are added. Recurring positive results may be appropriate for product rejection or supplier ineligibility, but total absence is not currently feasible. The assistance of existing national advisory committees or organizations may be useful in addressing this issue. 14

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program Indicator Microorganisms as Potential Predictors of Food Safety Samples of foods and surfaces may be analyzed for the presence of E. coli, Enterobacteriaceae, coliforms, fecal coliforms, or APC as indicators of sanitary conditions, hygiene, adherence to good manufacturing practices, proper or adequate processing, post-processing contamination, and storage time or temperature abuse. That enteric pathogens originate in the intestinal tract of animals and humans supports the biological rationale for using particular microbial indicators, especially E. coli, as indicators of potential contamination of food with fecal material except when possible growth has occurred because of poor cold chain management3. Although the probability that a pathogen is present may increase with under-processing, post-processing contamination, or manufacture under unsanitary conditions, the presence of an indicator is no guarantee that a pathogen is also present. There is no specific relationship between indicator and pathogen concentration, but it can generally be assumed that a reduction in the concentration of an indicator organism will produce a similar reduction in the concentration of the associated pathogen (Brown et al., 2000). For a microbial indicator to be an effective predictor of the presence of an enteric pathogen in a particular food, there is a need to establish a statistical association for the specific situation under consideration. Establishing an association between an indicator and a pathogen can be problematic because pathogens are generally present sporadically and in low numbers; therefore, a very large number of samples (thousands, tens of thousands, or more) is required to assess potential associations. To ensure compliance with AMS purchase standards, AMS periodically conducts inspections and collects and analyzes samples from production combo lots (each lot is approximately 2,000 pounds [907 kg] of boneless beef) to determine compliance with the TRS-GB. Aerobic (standard) plate count, total coliforms, generic E. coli, coagulase-positive Staphylococcus, Salmonella, and E. coli O157:H7 tests are performed in AMS-accredited laboratories, and the resulting data are accumulated. The data are used to make decisions regarding specific combo lots and to evaluate contractor performance with a moving window approach. Finding A6: The committee finds that AMS is in possession of potentially valuable datasets that can be used to study the strength of the statistical correlation between indicator organisms and foodborne pathogens in ground beef. Recommendation A6: The committee recommends that AMS investigate its own microbiological data to assess their utility in providing a scientific basis for the use of indicators in setting purchase specifications that reduce risk. Agricultural Marketing Service Microbiological Requirements As a technical requirement document for AMS purchase of ground beef items, the committee found the July 2010 TRS-GB (USDA-AMS, 2010a) to have little information on the scientific basis of the selection and adoption of the safety requirements for boneless beef and ground beef. Hence, to evaluate the scientific basis of the purchase requirements adopted by AMS, the committee relied on the information provided by AMS, and the ARS and FSIS representatives who attended the two committee meetings. They based their comments on personal knowledge, current legislation, and information that they received from a pool of industry representatives who were willing to discuss their criteria confidentially. 3 Maintenance of proper temperature control throughout the process of delivering the food to the end-user, from production, through processing and handling, transport and distribution. 15

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program The information given to the committee indicated that the AMS specifications were based primarily on expert opinion and industry practices and that AMS did not use the multiple years of microbiological data that it had collected from contractors’ samples. In one specific instance, AMS made a decision (the requirement for a minimum of two interventions with Critical Control Points to attain a 3- log or 99.9% reduction) on the basis of one retailer’s practices (M. E. O’Connor, USDA-AMS, Washington, DC, personal communication, Aug. 11, 2010). In some instances, requirements were made by using a “conservative or a precautionary approach” that was based not necessarily on existing data but instead on informal expert consultation. Finding A7: The scientific basis of the AMS technical requirements for the purchase of ground beef is questionable and might not reflect the best evidence available (see the section “Weight of Evidence and Role of Expert Opinion in Developing Science-Based Food Safety Requirements”). In addition, expert consultation was conducted in an informal, ad hoc, and nontransparent manner. Current industry practices were also used by AMS in establishing its purchase criteria, but the scientific basis of the industry practices cannot be ascertained by the committee. Recommendation A7: Expert consultation and industry practices can be helpful in making informed decisions in setting specifications and purchase criteria. However, the committee recommends that the solicitation and use of expert advice and industry practices be conducted in a structured, systematic, and transparent manner. In addition, the committee recommends that AMS consider examining the analysis of microbiological data collected from contractors’ samples to determine whether the data can provide an empirical basis for determining and evaluating purchase specifications (see Recommendation A6 above). Finding A8: No statistical assumptions, such as on the prevalence of pathogens or confidence levels, were used by AMS in defining sampling strategies and lot sizes (see discussion on sampling in the section “Heuristic vs Science-Based Approach to Developing Specifications and a Food Safety Assurance System”). Recommendation A8: Sample and lot sizes should be determined with statistical methods. Modeling techniques can also help in making decisions on lot sizes and can provide valuable information on the likelihood of accepting or rejecting a contaminated lot, which is directly related to public health risk. Criteria or requirements can be more readily justified if they are derived through statistical calculations and modeling techniques. Statistical Process Capability According to the July 2010 TRS-GB (USDA-AMS, 2010a), AMS will evaluate contractor performance through a statistical process capability assessment that is based on a moving window of 20 consecutive lots. The capability assessment method proposed in the July 2010 TRS-GB should be able to detect the increase in the frequency of positives for all contractors that had E. coli O157:H7–positive samples and should be able to trigger the mechanisms that would deem these contractors ineligible. Once ineligible, a contractor is excluded from the purchase program, at least temporarily, until it can provide AMS its plan for corrective actions. The plan for corrective actions is evaluated by an on-site assessment audit performed by AMS personnel. If approved, the contractor can re-enter the program in conditional status. In conditional status, the contractor has to have 20 consecutive results that meet “process-capable” criteria. That requirement has to be met within 60 calendar days or in accordance with the production schedule approved by the contracting officer. Finding A9: The AMS statistical process capability assessment for evaluating a contractor’s performance seems to be effective but is limited to a particular timeframe and does not consider the contractor’s performance over time. 16

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program Recommendation A9: AMS should attempt to identify risk factors for the presence of E. coli O157:H7 by using longitudinal analysis of historical data—using not only microbiological data but inspection scores, seasons, establishments’ characteristics, and other available information relevant to identifying risk factors for E. coli O157:H7 in ground beef. The process would probably assist in selecting contractors that are less likely to have ground beef contaminated with E. coli O157:H7. Finding A10: The July 2010 TRS-GB contains specifications that increase the testing requirements for ground beef. However, increased testing might not increase the safety of the product. Process control is a well-established method for improving food safety and is the basis of HACCP. Recommendation A10: AMS should ensure that suppliers of boneless beef and ground beef grinders are responsible for the safety of their products and for the management, performance, and improvement of their processes. Data on the product that are obtained by the food processors and the service need to be analyzed for TRS compliance, process stability, and process capability with appropriate statistical methods. It is recommended that AMS develop a strong supplier evaluation program that is based on statistical process control techniques and that encourages suppliers to improve both process and product performance. Evaluation of the Statement of Work for Agricultural Marketing Service–Accredited Laboratories The committee reviewed the June 2010 Statement of Work (SOW) (USDA-AMS, 2010b), which provides the requirements for laboratories seeking to enter into a service contract with AMS to collect samples, conduct required microbiological and fat tests, analyze the data, and report the results for suppliers participating in AMS’s Product Certification Service. Finding A11: The overall procedures for laboratory accreditation appear to be appropriate. According to the June 2010 SOW, the laboratory will be required to test for the presence of "Shiga-toxigenic E. coli O157 (including O157:H7 and O157:Non-Motile (NM), referred to in this document as E. coli O157:H7)". The SOW also states that screening tests detailed in the FSIS Microbiology Laboratory Guidebook (MLG), Chapter 5A.01 (USDA-FSIS, 2008a), can be used for E. coli O157:H7 testing. However, MLG Chapter 5.04 (USDA-FSIS, 2008b) indicates the following definition for reporting E. coli O157:H7: Confirmed Positive—a biochemically identified Escherichia coli isolate that is serologically (i.e., based on antigen-antibody characteristics) or genetically determined to be “O157” that meets at least one of the following criteria: 1. Positive for Shiga toxin (ST) production 2. Positive for Shiga toxin gene(s) (stx) 3. Genetically determined to be “H7” Hence, the definitions in the June 2010 SOW and MLG Chapter 5.04 seem to be inconsistent, inasmuch as a Shiga toxin–negative E. coli O157:H7 would be considered positive for E. coli O157:H7 by MLG Chapter 5.04 but not by the definition in the SOW. The SOW also did not provide details of how laboratories are expected to detect or identify O157: nonmotile. Recommendation A11: The committee suggests that AMS provide further clarification of the procedures that the laboratories are expected to use to detect and identify E. coli O157:H7 and that AMS clarify specifically how these methods are related to the methods and definitions detailed in the relevant MLG 17

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program chapter. AMS should also clarify how laboratories are expected to detect or identify O157: nonmotile (for example, with phenotypic or genetic tests). COMPARISON OF THE AGRICULTURAL MARKETING SERVICE SPECIFICATIONS WITH THOSE OF LARGE INDUSTRY PURCHASERS OF GROUND BEEF Current AMS specifications in the July 2010 TRS-GB (USDA-AMS, 2010a) for the Federal Purchase Ground Beef Program were extracted, summarized, and presented in tabular format (see Table 1). Microbiological specifications for retail and commercial or food service purchasers of ground beef were obtained through direct requests to companies or indirectly from requests to purchasers or suppliers through a representative industry association. Because of proprietary concerns raised by the companies that agreed to share their specifications through the American Meat Institute (AMI), the company names were removed from documents by AMI before their submission of the specifications to the committee. Each company was assigned a letter designation (A through X, as shown in Table 1). The committee is uncertain of the extent of the scientific evidence, if any, that supports the microbiological specifications provided by industry, either singly or combined into a program. No information was provided on the sampling plan (number of samples analyzed, analytical-unit size, and action taken if limits were exceeded), so calculation of the stringency of sampling plans was not possible. Moreover, different users may consider some measures as food safety specifications, as quality indicators, as tools for assessing process control, or as evidence of supply chain management. As a measure to protect public health, therefore, the comparison is of little value, or even of little purpose, because the scientific underpinnings of the specifications, excluding E. coli O157:H7 contamination, cannot be determined. Finding B1: Substantial variation in the data is evident. The reasons for the variation are uncertain; however, one factor that may account for at least some of it is the intended use of the product. For instance, product that is to be distributed fresh to a food service may require a lower specification limit if a longer shelf-life is required. As a consequence, comparisons of specifications have little meaning unless the basis of the specifications and the intended use of each product are known. Finding B2: The committee recognizes that AMS expected its specifications to be compared with or benchmarked against industry specifications. However, meeting that expectation relied heavily on the amount of information that the committee was allowed to access. It appears on the surface that AMS specifications are comparable with or even more demanding than those of the commercial companies, but the lack of information on intended use, sample size, sample number, or actions taken when specifications were exceeded renders comparison of AMS specifications with those of other companies inappropriate and scientifically invalid. 18

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program Table 1 Microbiological Specifications of Various Companies A Through X and Upper Specification and Critical Limits of AMSa, b Microbiological Characteristic Measured Qualitatively or Quantitatively Total S. Salmonella L. APC E. coli E. coli Company Coliforms aureus (CFU/g) (CFU/g) monocytogenes O157:H7 (CFU/g) (CFU/g) A 100,000 1,000 240 N/A N/A N/A B <50,000 <500 <10 <100 Min Min Neg C 750,000 1,100 240 <1,500 Min N/A D 250,000 N/A 110 Min Min E 1,000,000 5,000 — 240 Min Min F — — — — Min Min G 500,000 1,000 250 250 Min Min H 500,000 1,000 100 500 N/A N/A I 500,000 500 240 100 Min Min J <100,000 <500 <110 250 Min N/A K — — — — — — L 500,000 1,000 250 500 Min — M 500,000 1,100 100 — Min Min N — — — — — — O — — — N/A — — P 250,000 240 100 <500 Q <500,000 <1,100 N/A Neg R <1,000,000 <10 <3 110 Neg Min S 100,000 500 150 — Min Min T — — — 250 — — U 750,000 5,000 — <110 Min Min V <100,000 <500 <150 — — W 500,000 500 Neg X <100,000 <110 Neg AMS upper specification 50,000 100 100 500 limitc AMS 100,000 1,000 500 Neg Neg critical d limit a APC = aerobic plate count; dash = company’s default specification, not shown, used as company’s specification; empty cell = company does not include as a requirement in its specification; N/A = company does not require testing for organism as part of its specification; Min = minimizes occurrence of positives through Good Manufacturing Practices; Neg = negative. b Exceeding these specified limits typically results in rejection by companies A through V of the out-of-specification production unit; the same is probably true for companies W and X, but this was not confirmed. Disposition of product varies with microbial nonconformity; if positive for E. coli O157:H7, product may be rendered or sold for thermal processing; if other specifications are exceeded, product may be reprocessed or sold into secondary markets. 19

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program c For boneless and ground beef; used for evaluation of process capability. If process is deemed out of control by AMS, the company becomes ineligible as a supplier. S. aureus for ground beef only; if initial and backup ground beef samples exceed the S. aureus upper specification limit, production lot is rejected. d For boneless and ground beef; used to reject lot-by-lot data (whole-lot = “cleanup to cleanup” or sub-lot plus “shoulders” depending on positive sample, that is, if whole-lot sample or sub lot sample results in nonconforming test). RECOMMENDATIONS ON HOW TO PERFORM FUTURE EVALUATIONS RELATIVE TO RECOGNIZED BEST PRACTICES Heuristic vs Science-Based Approach to Developing Specifications and a Food Safety Assurance System Specification writers may use a heuristic approach to develop specifications, which focuses on using experience to develop specification and is based on the following assumptions:  The food safety assurance system has worked in the past.  The company has not shipped product that has caused a food safety incident.  Therefore, the system will work in the future. That approach assumes that the past conditions and “context” (dotted box in Figure 1) have not changed and will not change. However, if the “context” changes, the food safety assurance system may or may not be adequate to ensure shipment of safe food. Statistical techniques Sample Data Knowledge Actions Specifications Figure 1 Food safety assurance process to take appropriate action on a process or product lot. Context and conditions used to collect and analyze data are shown in dotted box. An alternative method of developing a food safety assurance system is to use a process- controlled science-based approach. This would be based on the idea that a properly designed system is statistically stable—that is, values obtained will fall between a set of mathematically defined limits—and capable of meeting specifications. It uses the tools of statistical process control to assess process stability 20

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program and process capability. Statistical process control is a powerful tool. It can be used by purchasers to monitor supplier performance: they can rank supplier performance, determine whether suppliers are continually improving their performance, and obtain quantitative knowledge of whether specifications are being met. A number of questions can be asked to determine whether an organization uses a science-based approach to develop a specification, including the following:  Was the level of risk for a food pathogen considered in developing the specification? This includes the potential concentration of the pathogen in the food, the infective dose of the pathogen, and the consequence of an illness.  Did the organization consider what may go wrong with the product and the process? When this question is asked, the organization needs to take action to minimize the occurrence of the hazard in the product or develop a testing procedure that identifies the presence of the hazard. In addition, the supplier should provide a plan to AMS describing how it will meet the specifications.  In developing a product compliance-sampling program, were proper statistical procedures used to ensure that the pathogen can be detected with a specific level of confidence? The number of samples analyzed should be determined in a manner that provides the organization with a specific level of confidence that a hazard is being controlled. For example, the sampling scheme could provide 95% confidence (or another level) that a specific amount of beef trim does not contain E. coli O157:H7. No practical sampling scheme can guarantee total absence of a microorganism (Table 2). For example, if the contamination rate of E. coli O157:H7 in lots of AMS ground beef is 0.13%, the proportion rate of E. coli O157:H7 in a lot of ground beef is 0.0013. Using that value, if AMS wants a 95% confidence level that a combo or lot of ground beef does not contain E. coli O157:H7, 3,000 samples need to be collected from the combo, and all the samples must test negative for the pathogen. In addition, the samples must be randomly collected from the meat trim that is present in the combo so that each piece of meat has an equal chance of being selected for testing. That level of sampling is not realistic for production of foods. HACCP has achieved its success by designing food safety into the manufacturing process. Thus, the only rational means of achieving continual reduction in pathogens is to control the process of manufacture of ground beef from harvesting to packaging of the frozen patty and use statistical process control tools to monitor the process, and use continual improvement techniques to improve process and process performance. 21

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program Table 2 Relationship of Number of Units Sampled and Portion of Lot That Contains a Pathogen for 95% Confidence in Detection No. Samples That Must Be Tested for Proportion of Lot Contaminated with Hazard Detection 0.001 3,000 0.005 600 0.010 300 0.020 150 0.030 100 0.040 75 0.050 60 SOURCE: ICMSF (2002) and ASQ (2008). NOTE: Sampling plan assumes that no samples are positive (c=0).  If the testing system indicates that something has gone wrong, does the organization use root- cause analysis to try to determine a reason for the problem and then take effective action to prevent the cause in the future? This analysis will not always determine a specific root cause of a problem.  Are proper testing and sampling methods used to gather and test the samples? The methods will be based on a proper level of precision and accuracy to ensure that the proper actions are taken. In some cases, tests may involve measurements of physical characteristics (such as time, temperature, and pH) rather than microbiological tests.  Does the food safety assurance program focus on prevention or on detection of the hazard? The most effective food safety assurance program is based on preventing the occurrence of a food safety hazard rather than detecting the hazard in an ingredient or the final product. The focus of the science-based approach is to understand the context of the food safety assurance system (Figure 1). Once the “context” is understood, a food safety assurance system can be developed to ensure the shipment of product that meets defined food safety requirements Weight of Evidence and Role of Expert Opinion in Developing Science-Based Food Safety Requirements The committee spent considerable time in discussing what science-based means for food safety requirements in the Federal Purchase Ground Beef Program. Ultimately, it implies evidence obtained through the use of the scientific method to formulate and test hypotheses, using rigorous means of data collection, analysis, and interpretation so that the results of an investigation (or series of investigations) may be judged as valid and reliable through a process of peer review and replication. However, the committee recognizes that such scientific evidence is not always available to serve as the basis of decision-making, especially in response to rapidly changing circumstances. Thus, decisions inevitably will be made under conditions of uncertainty and using the best available evidence. As part its deliberations, the committee discussed what might constitute superior evidence and found the hierarchy proposed by Roudebush et al. (2004) to be helpful. The committee proposes a diagram for classifying science-based food safety requirements by AMS. Figure 2 shows the hierarchy that the committee would like AMS to consider. The committee notes that several of the components of the diagram may have 22

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program equivalent rankings in usefulness, so to some extent the rankings are somewhat artificial. Nevertheless, the committee believes that AMS should consider some sort of hierarchy in evaluating science-based requirements. At the bottom level of the diagram is informal ad hoc expert opinion (discussions with individual experts). Expert opinion may be the only option in some cases, and AMS should consider it an evidence option of last resort. In specific instances in which AMS has used expert opinion, it should seek to validate it by collecting data and preparing an internal report. If the findings of the report contradict the expert opinion, AMS should stop following it. One example regarding apparently conflicting expert advice involved the risk posed by use of XF trim (beef fat with visible lean) as a stand-alone source for grinding. It appears that some experts consulted by AMS suggested that XF trim represented an increased risk of E. coli O157:H7 contamination, whereas experts (those invited to speak at the meetings) consulted by the committee suggested that there is no evidence that XF trim has an increased risk of this contamination. That conflict of opinion requires data to resolve, and the results of a carefully executed study could help to inform AMS and industry practices.  Peer-reviewed reports and risk assessments  Formal expert consultation (for example, with NACMCF) Increasing  Internal reports based on relevant AMS data Weight of  Reports based on confidential data that are not peer-reviewed Evidence  Industry standards/best practices  Informal ad hoc expert opinion Figure 2 Hierarchy of science-based food safety evidence. Weight of evidence increases as it approaches the top of the list. At the second level are industry standards and best practices. These are more useful than ad hoc expert opinion because they may reflect a broader consensus among multiple experts. However, the committee cautions that it would be problematic to adopt multiple practices from a variety of sources and simply add them to existing AMS requirements. First, the committee notes that a particular best practice may be specific to a given company and that all the other programs may influence the practice that the company has in place; thus, its performance in another context may be different. Second, the committee notes that if AMS continues to add requirements without evaluating its existing requirements, the system that results may be needlessly complex and not provide the food safety assurance of a simpler system. For example, a requirement for a 3-log reduction in interventions at slaughter operations, which was based on a similar requirement recently announced by one retailer (Gabbett, 2010), was added to an existing AMS requirement that slaughter operations use two interventions with Critical Control Points. The new requirement added complexity in not specifying how a 3-log (99.9%) reduction in two combined interventions should be validated. Treatment A may result in a 1-log (90%) reduction and treatment B in a 2-log (99%) reduction on the basis of independent laboratory studies. Combining the treatments may indeed lead to a 3-log reduction, but they might not be additive, for example, because of cross-protection. Furthermore, two slaughter operations that start with different levels of contamination will necessarily achieve different levels of protection when a consistent 3-log reduction is applied. The outcome of the 23

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program interventions has greater relevance to food safety management than does the level of reduction at one stage for the complex food system involved in production and processing of ground beef. At the third level are reports based on confidential data that are not peer-reviewed. The committee notes that some data are usually better than no data, but confidential data that are not subject to peer review or even AMS internal review warrant skepticism. AMS should seek ways to encourage the review and sharing of data in a manner that promotes the needs of AMS, advances science, and protects confidentiality to the greatest degree possible. In addition, it is important to review the objectives and procedures of data collection by different sources, inasmuch as they may vary and influence the data collected, their value, and their interpretation. At the fourth level are internal reports based on relevant AMS data. As noted above, in specific instances in which AMS uses expert opinion (such as the case of XF trim use), it is appropriate to validate it by collecting data and publishing an internal report. Such analysis will give AMS a stronger scientific base on which to justify its requirements. A report that outlines the assumptions and rationale for AMS specifications will be useful when questions arise on the origin and suitability of the requirements. At the fifth level is formal expert consultation (for example, with NACMCF). Unlike ad hoc expert opinion, formal consultation with a diverse group of experts who have different backgrounds and different constituencies can provide more confidence in decision-making. The committee assumes that formal expert consultation provides an opportunity for different experts to debate varied points of view and to reach consensus through the use of the array of evidence listed in Figure 2. Moreover, a carefully designed expert consultation process permits consideration of the entire context of a situation within which individual factors can differentially affect food safety outcomes. In contrast, ad hoc expert opinion might address only one aspect of a program and not consider other elements or unintended consequences that may affect an entire food safety program. At the top level of the diagram are peer-reviewed reports and risk assessments. An expert consultation that is subjected to peer review may fall into this category. The committee notes that such a high standard may be difficult to achieve regularly, but it is nevertheless a goal. AMS has a unique opportunity to establish itself as a food safety leader by taking all possible steps to base its specifications on the highest standards. Finding C1: In the recent update of the AMS purchase specifications, there was a heavy reliance on informal ad hoc expert opinion, which the committee determined to be the least-preferred form of evidence. Elements of the program appear to have been gathered from multiple sources (such as log- reduction requirements, concentrations of indicators, and actions taken if positives are found) with no evidence of a process that considered the entire context of a situation to develop a unified and cohesive program. The scientific basis of the AMS purchase specifications would be strengthened by the use of resources that yield more reliable evidence and that are consistent with the entire context of AMS’s need to develop a cohesive program. Recommendations relevant to this finding are offered later. Other Considerations As a large purchaser of ground beef for distribution to the school lunch program, emergency feeding programs, food banks, protective shelters, disaster-relief programs, reservations, and other eligible programs that serve the food-insecure, AMS serves members of society who may be most vulnerable to foodborne illness and its consequences, including children, the elderly, and the immunocompromised. It is essential that the specifications set by the USDA Federal Purchase Ground Beef Program are based on the best available science and have as goals protecting public health and ensuring that the ground beef products purchased in the program are safe, nutritious, wholesome, and of high quality. 24

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program The American public and elected representatives must have confidence that the specifications established by AMS for its purchase of ground beef will accomplish those goals. As the result of a series of highly publicized food recalls and illness outbreaks involving foodborne pathogens, the American public and the mass media have become particularly sensitized to issues of food safety. Most Americans say that they have heard of a recent food recall and that they are familiar with recent recalls of ground beef (Hallman et al., 2009). Recent surveys suggest that American consumers rank the healthfulness and safety of food high on their list of concerns (Deloitte, 2010). Moreover, a recent study indicates that the public believes that the most important food safety issues today are “foodborne illnesses from bacteria”, followed closely by “chemicals in food”, and that most consumers believe that food safety is the responsibility primarily of the government and industry (IFICF, 2010). Maintaining the confidence of Americans in the safety, wholesomeness, quality, and nutritional value of the products that they purchase is especially important because of the nature of the AMS commodity program and its clientele. In particular, the NSLP serves more than 31 million children a day. Children who are eligible for the NSLP typically come from low-income and food-insecure families and so have little choice but to eat what is provided by the program. As a consequence, real or perceived problems with the safety of the foods provided by the NSLP may be seen by the public as leading to involuntary exposure of particularly vulnerable children to unnecessary risks. In that respect, AMS may be seen as a proxy for American parents and others in society who want to safeguard children by having them served only safe, wholesome, high-quality, nutritious foods. Loss of confidence in the NSLP “brand” might lead parents to advise their children to avoid eating school lunches that are provided through the program, and this is likely to lead to the consumption of less healthy alternatives. It might also lead to a lack of support for the program among taxpayers and their representatives, which could result in a reduced ability of the NSLP to meet the needs of eligible children. AMS may find it reasonable to adopt and implement conservative standards and requirements that are protective of public health and can easily be understood by the public as providing the highest degree of food safety, quality, wholesomeness, and nutrition. Continuing efforts to benchmark AMS specifications against specifications that are maintained by industry leaders and are science-based may help in that regard. However, AMS also needs to consider carefully the potential unintended consequences of increased testing and product requirements. Additional testing requirements are likely to increase costs to producers. If those costs seriously affect the purchase price of ground beef available through the commodity program, schools may decide to buy their ground beef on the open market at a lower cost and to reserve their available commodity credits to purchase other items. In effect, if AMS opts to set specifications far above industry practices that are based on scientific principles, the added costs of meeting the specifications might lead to the increased consumption of ground beef produced under much lower standards. The effect of the AMS corrective action procedures (rejecting of all product in a lot for all USDA food and nutrition programs) vs those of industry (such as identifying and correcting causes, using data in a moving window, and isolating specific product for alternative processing or rejection) may also add cost to the system without public health benefit. Overall Findings and Recommendations on How to Perform Future Periodic Evaluation of the Federal Purchase Ground Beef Program Finding C2: In developing its current purchase specifications for ground beef, AMS did not follow a procedure based on the scientific principles described by the National Research Council, the International Commission on Microbiological Specifications for Foods (ICMSF), and Codex Alimentarius Commission (CAC). Recommendation C2: AMS is encouraged to develop a systematic, transparent, and auditable system for modifying, reviewing, updating, and justifying purchasing specifications that are science-based—that is, 25

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An Evaluation of the Food Safety Requirements of the Federal Purchase Ground Beef Program specifications that are based on scientific principles as described in previous National Research Council, ICMSF, and CAC publications—and that state the expected public health benefits where appropriate. This would include specifying the use of pathogen detection methods that are among the most reliable available for use in related food safety programs. It may be appropriate for AMS to collaborate with ARS, FSIS, and CDC and potentially with other groups, such as NACMCF, to develop a risk-based system for assessing public health effects of purchasing specifications not just for frozen ground beef but for various products purchased by AMS for the NSLP and other programs. Finding C3: Microbiological data collected by processors and AMS to verify compliance with testing requirements in purchasing contracts could be valuable for use in process control, improvement, and future program modifications. Recommendation C3: AMS should develop a system for regular and continuous use of data collected in its purchasing program for evaluation of program outcomes and process controls applied by suppliers and for developing recommendations for future actions. The committee suggests that if AMS has specific questions about the details of appropriate data analysis methods it discuss the matter further with relevant experts; with FSIS, USDA Office of Risk Assessment and Cost-Benefit Analysis statisticians or risk modelers; or with AMS personnel who are competent to analyze data by using time-series process control analysis. Finding C4: An important issue that needs attention is the disposition of product lots when testing indicates that they do not meet AMS specifications. The committee determined that the final disposition of such product should be based on scientific principles that protect public health without wasting economic resources. Recommendation C4: AMS’s goal should be to protect public health by removing potentially unsafe product from the food supply through safe disposition, when advisable, such as directing it to safe further processing, rather than removing it completely from the Federal Purchase Ground Beef Program. In addition to providing guidance as to how such product is diverted, AMS could provide a mechanism for verifying its appropriate diversion. AMS is encouraged to develop science-based approaches for proper use of raw materials that do not meet its specifications. Finding C5: AMS has identified current hazards of concern in raw ground beef for children in the NSLP (E. coli O157:H7 and Salmonella). Recommendation C5: Although E. coli O157:H7 is the most important concern in raw beef products, other Shiga toxin–producing enterohemorrhagic E. coli serotypes (such as O26, O45, O103, O111, O121, and O145) are also capable of causing human infection. Other enteric pathogens that may occur in ground beef and are considered by experts and public health authorities to be of potential major concern to sensitive populations (such as schoolchildren) are antibiotic-resistant (especially multiple-drug–resistant) strains of Salmonella. The committee believes that it would be useful for AMS to follow developments associated with those pathogens and other emerging pathogens and to create strategies for the protection of vulnerable consumers. It is recommended that AMS apply formal and transparent procedures to perform periodic evaluations of pathogens of concern, including those of emerging concern. Efforts to accomplish that task should be through AMS partnerships with sister agencies, such as ARS and FSIS, but also with CDC and national advisory committees and other organizations. Finding C6: AMS has sought advice and input from ARS, FSIS, industry, and the National Research Council (the current committee) in establishing and reviewing its specifications. Recommendation C6: The committee recommends that outreach for advice continue and be expanded by considering the use of existing advisory bodies on microbiological criteria, such as NACMCF, for periodic evaluation of purchasing specifications for meat and other commodities. 26