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OCR for page 174
7
Policy Options to Reduce Exposure to
Dioxins and Dioxin-like Compounds
INTRODUCTION AND BACKGROUND
The central task assigned to the committee was to identify risk-management
options to reduce exposure to dioxins and dioxin-like compounds (referred to
collectively as DLCs) through the food supply and to recommend ways to mini-
mize current exposure levels. The committee was not asked to do risk assess-
ment, thus the focus was on evaluating risk relationships and risk-management
options.
In the course of its deliberations, the committee considered many potential
intervention scenarios within the framework outlined in Chapter 6. These inter-
ventions can be initiated at a number of points along the animal production,
human food, and food-consumption pathways (Figures 7-1 through 7-3~. The
generated range of risk-management options took into account current statutory
food safety standards and other regulatory policies, procedures, and practices that
frame and constrain the adoption of regulatory interventions. The committee also
considered risk-management options that involve encouraging voluntary actions
that could be taken by food system participants to reduce DLC exposure. As
explained in Chapter 6, the committee considered these options within an overall
framework of a risk relationship analysis.
The committee' s approach was to deliberate and present a broadly represen-
tative list of risk-management options and some guides toward the evaluation of
the desirability of these options. All of the options presented have the intention of
reducing DLC exposure through food, working from the starting point that reduc-
tions in exposure are desirable. However, a central conclusion of the committee is
that the desirability of particular risk-management options in many instances
174
OCR for page 175
POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
1
Harvested Cereals,
Forage, Grasses,
Others
ENVIRONMENT
Generation
Chemical Processing
Combustion I
Worldwide Reservoir
Sediments
Waterways
A ~
/ \ Vegetables,
_ / Cereals
~ ~
lie ~
Terrestrial
Animals
\
-
Animal
Feed
+ :
-
Fishmeal,
Fishoils,
Animal Fats
nor] Prordil~t.
1
HUMAN FOODS
Meat, Fish, Dairy,
Eggs, Fruits,
Vegetables, Cereals
~ Humans ~
175
~ 1
Aquatic
Animals
/
i,:/
x
FIGURE 7-1 Pathways leading to exposure to dioxin and dioxin-like compounds through
the food supply. Boxes depict point sources in the pathways. Dark arrows refer to path-
ways with a greater relative DLC contribution than the pathways with light arrows.
cannot be adequately analyzed due to insufficient information. Regulatory agen-
cies have invested relatively little toward generating the data required to support
risk-management decisions related to options to reduce DLC exposure. For ex-
ample, little data are available that would permit more refined estimates of cur-
rent DLC levels in feeds, forage, and human foods; the current distribution and
OCR for page 176
176
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
ENVIRONMENT
Generation
Chemical Processing
Combustion
~ Worldwide Reservoir
/ Sediments
/ Waterways
l Soils
Harvested Cereals, / \
Forage, Grasses,
Others ~~ \
_ ~ ~ Animal 1
Fishoils, 4~
Animals
Fishmeal,
Fishoils,
Animal Fats
and Products
PATHWAY I
Aquatic
Animals
FIGURE 7-2 Pathway I, animal production systems. Boxes depict point sources in the
pathways. Dark arrows refer to pathways with a greater relative DLC contribution than
the pathway with a light arrow.
levels of human exposure; and the amount of exposure reduction that could be
achieved through various interventions.
The risk-management options discussed by the committee encompassed a
wide range of regulatory and nonregulatory options, which are presented in this
chapter. The options are presented in outline form in matrices that correspond to
each of the three pathways (see Chapter 6) and are discussed in detail. Not all of
the options considered were selected as recommendations for immediate action;
specific recommendations and research needs are presented in Chapter 8.
The committee analyzed only the likely outcomes or the ultimate desirability
of the most significant risk-management options considered. Thus, the matrices
contain an array of options greater than those that the committee considered in
detail. The listings of current barriers to implementation, expected DLC exposure
OCR for page 177
POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
I
l _
Terrestrial
Animal
\
HUMAN FOODS
Meat, Fish, Dairy,
Eggs, Fruits,
Vegetables, Cereals
Humans
Vegetables,
Fruits,
Cereals
Aquatic
Animals
,,N~:2
N~
.~
~ NNN~
177
-
FIGURE 7-3 Pathway II, human foods, and Pathway III, food-consumption patterns.
Boxes depict point sources in the pathways. Dark arrows refer to pathways with a greater
relative DLC contribution than the pathways with light arrows.
reduction, and risk relationships (ancillary benefits and countervailing risks)
should be viewed as suggestive not definitive. Additionally, due to gaps in data
and high analytical costs, many options are not feasible for immediate implemen-
tation, although they may be used in the future.
The size and direction of these impacts must be the subject of further analy-
sis. For example, a potential countervailing risk of several options could occur
through the following chain of events: higher costs of production cause higher
prices for some food products (e.g., meat and dairy products), and consumers
shift away from the higher-priced foods to the lower-priced foods, which results
in less access to important nutrients and a negative impact on nutritional status.
The committee's evaluation of the available economic research suggests that this
chain of events is unlikely unless price changes were large (i.e., greater than 10
percent) and widespread. Moreover, some of the effects of shifts in diet are likely
to provide ancillary health benefits, either through reduction in intake of dietary
constituents that are currently consumed in excess, or through increased intake of
OCR for page 178
178
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
constituents that are consumed at suboptimal levels. However, inclusion of this
possible risk relationship in matrices suggests the need for further evaluation.
While the committee did not fully analyze the available risk-management
options, it did identify two areas that appear to be the most promising leverage
points for affecting DLC exposure from food. One of these is at the animal
production stage, where DLCs enter the food supply through forage and feeds
and are subsequently recycled back through the system by practices such as the
reuse of animal fats (where DLCs accumulate) as ingredients in animal feeds.
The second leverage point is in food-consumption patterns, where consumption
of foods with higher levels of animal fat, particularly by children, contributes to
DLC exposure and life-long DLC body burdens. These two areas are where
further analysis of risk-management options should begin.
ENVIRONMENTAL CONSIDERATIONS
The committee was clearly instructed by the sponsors to address ways to
reduce DLCs in the food supply, but not the environment. However, the commit-
tee felt it was necessary to take into account the sources of the DLCs that enter
feeds and foods. Therefore, the committee addressed reservoir and high-exposure
sources of DLCs as contributors to the overall exposure through foods.
Dramatic reductions have occurred in the production of DLCs from combus-
tion sources in the United States as a result of enforcement of the provisions of
the Clean Air Act. For example, DLC emissions from municipal waste incinera-
tors fell from 8,877 g TEQDF whop in 1987, to 1,250 g TEQDF whole in 1995,
and are projected to fall to 12 g TEQDF whorl in 2002 to 2004 (Winters, 2001~.
There have been similar dramatic declines in emissions from medical waste
incinerators, smelters, and cement kilns. The largest current source of DLC pro-
duction in the United States is now backyard barrel burning (estimated at 628 g
TEQDF wHOg~/Y) and other poorly characterized sources such as sewage sludge
application, residential wood burning, and coal-fired utilities.
Actions should be taken at all possible levels to monitor and reduce emis-
sions from these poorly characterized sources. The net effect of restricting the
emission of DLCs into the atmosphere is a long-term continual decline in DLC
levels in pastureland, soil, and sediment and, thus, reduced entry of these con-
taminants into the pathways that lead to human exposure through the food supply.
PATHWAY I: ANIMAL PRODUCTION SYSTEMS
Effective, long-term reduction of DLC exposure through the human food
supply requires interrupting the introduction of DLCs into pathways leading to
human foods. Thus, a range of possible measures to reduce DLC levels in forage
and feeds were identified and are presented in Matrix 1. Due to global environ-
OCR for page 179
POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
179
mental contamination, it is expected that all forages and many grain sources will
have detectable, although widely variable, DLC levels.
The gaps in current information on the quantitation of risks due to DLCs in
forage and feeds make it more difficult to develop uniform policy. However,
research studies currently underway will improve future decision-making options
for the management of these issues.
Option: Require Testing for DLC Levels in
Forage, Feeds, and Feed Ingredients
This option would require feed manufacturers and animal producers to test
samples of forage, feeds, and feed ingredients used in animal production systems
to determine DLC levels in these products. Data would be collected for samples
of ingredients, with the sampling and tracking of samples being performed under
close supervision. The data obtained from testing and surveys would be com-
bined with data from other sources to form a nationwide database on the levels
and distribution of DLCs in forage, feeds, and human food. The database would
be developed and maintained as a private/public cooperative project, with partici-
pation from meat and produce commodity groups, feed manufacturers, meat and
vegetable/fruit processors and retail markets, state departments of agriculture and
public health, and the U.S. Department of Agriculture (which would act as the
lead). An interagency coordination group should develop sampling priorities to
identify and remediate deficits in DLC contamination data for all feeds, feed
ingredients, forage, and animal production environments associated with produc-
tion agriculture and for the human food supply. In addition, the interagency
coordination group should develop uniform sampling techniques, analytic pro-
cesses and data reporting, and storage algorithms to enable direct cross-industry
and regional comparisons.
To supplement the mandated testing, government agencies, commodity
groups, and other food industry suppliers, including importers, would be encour-
aged to supply analytic and descriptive product data to further expand the avail-
able information. All data collected should be maintained with source anonymity
and be collected for informational purposes only. As data accumulate and are
evaluated, modifications in collection procedures may be required to maximize
the resources available to the industry and the government.
The justification for mandated testing, as discussed in Chapter 4, would be
the need to build the base of data required to support a coherent risk-management
strategy to identify and remove DLCs sources that enter animal production sys-
tems and, thus, interrupt the cycle that allows DLCs to accumulate in the human
food supply. At present, DLC data are collected piecemeal and are insufficient
for use in tracking regional or national trends. Under a mandated data collection
and distribution system, disparate public and private information resources would
OCR for page 180
180
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
Matrix 1. Intervention Options Considered to Reduce DLC
Exposure Through Pathway l: Animal Production Systems
A. Require testing for DLC levels in forage, feeds, and feed ingredients
Alternate/lnterim Establish a national voluntary monitoring and information
Actions system for DLCs in forage, feeds, and feed ingredients:
1. Develop new, less costly methods for DLC analysis
2. Encourage cooperative reporting of DLC results among
feed manufacturers and other industry suppliers
3. Continue or expand government DLC monitoring
programs
4. Make monitoring data available to industry and to the
public
Current Barriers to Current food safety laws are not applicable to DLCs
Implementation The current cost of analysis creates a barrier to required
testing
DLC Exposure Results of testing provide supportive data to establish
Reduction acceptable levels of DLCs in forage, feeds, and feed
ingredients and augment monitoring for unintentional
contaminants
Risk-Relationship Ancillary Benefits: An expanded database to track
Analysis unintentional contaminants in forage, feeds, and feed
ingredients that could be used in conjunction with forthcoming
analyses of the human food supply
Countervailing Risks: Possible increased cost of some foods,
which may decrease the availability of these foods and impact
the nutritional status of at-risk populations
B. Establish tolerance levels for DLCs in forage, feeds, and feed ingredients
Alternate/lnterim 1. Implement avoluntary program to reduce DLC-
Actions contaminated fat in animal feeds
2. Establish nonbinding targets for DLCs in forage, feeds,
and feed ingredients
Current Barriers to Data are insufficient to establish specific evidence-based DLC
Implementation levels, and there is a low-priority resource status for
implementing industry- or government-sponsored testing
programs
DLC Exposure Reduced levels of DLCs in animals and farmed fish that enter
Reduction the food supply
Risk-Relationship Ancillary Benefits: Long-term reduced levels of other
Analysis undesirable lipophilic contaminants that have been found with
DLCs in fats from animal-based foods
Countervailing Risks: Possible increased cost of some foods,
which may decrease the availability of these foods and impact
the nutritional status of at-risk populations
C. Restrict the use of animal products and forage, feeds, and feed ingredients
that originate from specific areas that are considered to be contaminated
OCR for page 181
POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
18
Alternate/lnterim 1. Identify and target for further analyses those geographic
Actions areas with high potential for contamination and determine
appropriate reduction strategies
2. Implement educational strategies to teach consumers
who reside in contaminated areas how to modify cooking
and food preparation to minimize exposure
Current Barriers to The uncertainty of risk and insufficient forage, feed, or feed-
lmplementation ingredient data available to assess local, regional, or national
contamination levels and identify high-risk contaminant
classifications
DLC Exposure Reduced levels of DLCs in animal feeds that contain fats from
Reduction animal sources
Risk-Relationship Ancillary Benefits: Decreased opportunity for other
Analysis undesirable contaminants that have been found with DLCs in
lipid-based ingredients to enter into food animals and farmed
fish via feeds
Countervailing Risks: Possible increased costs of some foods,
which may decrease the availability of these foods and impact
the nutritional status of at-risk populations
D. Restrict the reuse of the animal by-products in agriculture, animal
husbandry, and manufacturing processes
Alternate/lnterim 1. Work with industry to develop voluntary good agricultural,
Actions animal husbandry, manufacturing, and transportation
practices to achieve reduction in DLCs:
a) Monitor building materials and bedding for DLC
contamination
b) Eliminate growing foods and forages in high-exposure
areas or do not use first-cut forages from high
exposure areas
c) Increase intensive growing practices for livestock
d) Reduce or eliminate the use of animal fats and oils,
which may be high in DLCs, as ingredients in animal
feeds
2. Provide subsidies to encourage the adoption of practices
that reduce DLCs in forage, feeds, and feed ingredients
Current Barriers to The use of vegetable fats may lead to increased spoilage and
Implementation off-flavors in some products; disposal of unused animal fats
will create additional environmental problems
DLC Exposure Reduced reintroduction of DLCs into animal production
Reduction systems, which will reduce DLC levels in human foods in the
long-term
Risk-Relationship Ancillary Benefits: The entry of other undesirable lipophilic
Analysis contaminants into lipid-based agricultural products also is
reduced as a result of revised production practices
Countervailing Risks: Possible increased cost of some foods,
due to costs of expanded testing and reporting, which may
decrease the availability of these foods and impact the
nutritional status of at-risk populations
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182
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
combine, over time, into a body of information that would be useful for an
ongoing analysis of risk and the development of risk-management strategies that
reflect the evolution of environmental DLC levels.
Alternate/Interim Actions
An alternative to mandated DLC testing is a voluntary national monitoring
and information system, developed to contain reported DLC levels in forage,
animal feeds, feed ingredients, and animal production environments as described
above. This option was developed in consideration of available regulatory tools
and the constraints inherent in using them.
Current Barriers to Implementation
Current food safety laws do not provide regulatory agencies with the legal
authority to mandate testing except possibly as part of a regulatory intervention
that the agencies could justify as necessary to prevent illegal "adulteration" of a
product. As discussed in Chapter 6, the evidence required for this appears not to
be currently available. Thus, new legislation would likely be required to adopt the
mandatory data collection option. The committee assumes that, under current
law, the agencies could collaborate with the private sector in a voluntary data
collection effort. Beyond legal authority, the committee strongly believes that a
major factor in the paucity of DLC contamination data for all feeds and food
classes is the high cost and complexity of available, validated analytic proce-
dures. New and less costly methods for DLC analysis in forage, feeds, feed
ingredients, and animal production environments, as well as in a wide range of
food commodities and processed foods, should be encouraged. Screening tests
that detect baseline contamination levels at costs that are significantly below
current levels, as well as simplified instrumentation and detection processes, are
needed to move forward. Funding for developmental research in DLC detection
methods should be encouraged as part of the national research agenda.
DLC Exposure Reduction
Identifying "hot spots" where DLC contamination is particularly high would
help narrow the focus for short-term or immediate interventions to reduce DLC
exposures to food animals through forage and feeds. Such actions would also
help minimize problems that could arise from the intermingling of food animals
raised in areas where a contamination event has occurred with those raised in
uncontaminated areas. Long-term testing would further allow for trend monitor-
ing to map the rate of decrease of DLCs in exposure pathways and would be a
useful adjunct to monitoring for human exposures and health outcomes that chro-
nologically coincide with trends in DLC levels.
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
Risk-Relationship Analysis
183
Ancillary Benefits. The committee did not identify a specific ancillary ben-
efit to mandated or voluntary DLC testing and establishment of a nationwide
database other than the possibility that the proposed system may, in the future, be
useful in identifying other unintended or unwanted contaminants (similar to
DLCs) in animal production systems.
Countervailing Risks. A potential countervailing risk could occur if imple-
mentation of this option increased the cost and prices of some foods. However,
the size of the production-cost increases resulting from expanded testing and
reporting, and the resultant consumer-level food price increases, would have to
be significant for this to be a strong likelihood. The committee did not view this
as probable.
Option: Establish Tolerance Levels for DLCs in
Forage, Feeds, and Feed Ingredients
The option to regulate DLC levels in forage, feeds, and feed ingredients
would likely take the form of tolerances or action levels (see Chapter 6~. These
levels would be set, based on current DLC levels in forage, feeds, and feed
ingredients and projected target levels, to achieve exposure reduction. Setting
tolerances or action levels requires that the levels be set at a maximum limit
necessary to protect public health (see Chapter 6~. Tolerances, but not action
levels, are legally binding and enforceable through court action. The purpose of
setting tolerances or action levels for DLCs is to achieve a specific reduction goal
that is consistent with a maximum level of exposure considered to be safe. The
justification for setting tolerances or action levels is based on the premise that
DLC exposure reduction is necessary for public health and safety.
Alternate/Interim Actions
As an alternative to the binding limitations established by tolerances, it may
be feasible to set nonbinding goals aimed at reaching lower DLC levels in forage
and feeds that would minimize the amounts of these compounds available to food
animals through these pathways. Furthermore, by maintaining flexible and ad-
justable goals, these nonbinding target levels could conform to changing trends in
environmental DLC loads as new data are gathered.
Current Barriers to Implementation
The limited amount of data available on DLC levels in forage and feeds
creates a barrier to establishing enforceable tolerance levels. However, even if
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184
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
tolerance levels were in place, foods such as wild-catch fish and imported foods
would be missed by established feed regulations. An additional barrier to imple-
menting enforceable tolerance levels is that testing is expensive.
Establishing nonbinding goals to reduce DLC levels in animal forage and
feeds is limited by the expense and difficulty of the analytical procedures cur-
rently in place. There is also the question of whether nonbinding goals would be
followed and whether they would achieve a reduction in DLC levels in these
products.
DLC Exposure Reduction
Implementing measures to ensure that DLCs are reduced in animal forage,
feeds, and feed ingredients is an important point of intervention in reducing
DLCs in human food because the contamination of animal feeds is directly linked
to the presence of contaminants in human food. By establishing maximum limits
for DLCs in animal feeds, products contaminated at levels above the defined
limits would be legally excluded from the food supply.
Risk-Relationship Analysis
Ancillary Benefits. If taking action to reduce the source of DLCs in the food
chain results in a decrease in other hazardous contaminants, this could produce an
ancillary risk-reduction benefit.
Countervailing Risks. A potential countervailing risk could occur if imple-
mentation of this option increased the cost and prices of some foods. However,
the size of the production-cost increases resulting from expanded testing and
reporting, and the resultant consumer-level food price increases, would have to
be significant for this to be a strong likelihood. The committee did not view this
as probable.
Option: Restrict the Use of Animal Products and Animal Forage, Feeds,
and Feed Ingredients That Originate from Specific Areas That Are
Considered to Be Contaminated
This option mandates that forage, feeds, and feed ingredients obtained from
geographic regions known to be contaminated with greater than background
levels of DLCs be removed from animal production systems, and that the use of
animal food products obtained from contaminated areas be restricted.
This option may also be a means to protect potentially highly exposed popu-
lations from DLC sources in their immediate areas. Within specific geographic
regions, certain populations may have higher daily intake levels of DLCs than the
general population, due to food-consumption patterns, use of locally obtained
OCR for page 191
POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
191
Current Barriers to The lack of current data is a barrier to setting enforceable
Implementation standards
DLC Exposure Reduced levels of DLCs in human foods, although food
Reduction processing and packaging appear to play minor roles in
human exposure to DLCs
Risk-Relationship Ancillary Benefits: The cost of a DLC monitoring program for
Analysis food packaging materials could be spread over several
suppliers within the industry, thus diminishing the cost to
individual companies
Countervailing Risks: Possible increased costs of some foods,
which may decrease the availability of these foods and impact
the nutritional status of at-risk populations
C. Require cleaning or washing practices for all vegetable, fruit, and grain
crops that potentially had contact with soil
Alternate/lnterim Recommend washing practices to consumers
Actions
Current Barriers to Cost impact is assumed to be small
Implementation
DLC Exposure Reduced levels of DLCs in processed foods of nonanimal
Reduction origin
Risk-Relationship Ancillary Benefits: May reduce exposure to bacterial and other
Analysis food contaminants, especially on fresh fruits, vegetables, and
grains
Countervailing Risks: Possible increased costs of some foods,
which may decrease the availability of these foods and impact
the nutritional status of at-risk populations
Option: Establish Enforceable Standards for DLC Levels in Processed
Foods and in Food-Product Packaging That Directly Contacts Foods
This option mandates that, within the current regulatory framework, enforce-
able standards be set that limit the maximum allowable DLC levels in materials
used for food packaging.
In the past, DLCs have been found to enter the food supply through the
processing and packaging of foods (see Chapter 4~. Fortunately, these instances
were infrequent and corrective measures were taken. In addition, there are no
materials currently in use in processing and packaging that are known sources of
DLCs. Based on past experience, predicting inadvertent contamination events
that may occur through processing, although not easily done, would be prudent as
a means of preventing contamination incidents in the future.
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192
Alternate/Interim Actions
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
An alternative option is for regulatory agencies to develop a proactive moni-
toring program that will identify DLC-contaminated food packaging materials
for removal prior to their use. As an example of ways to reduce DLC levels by
exploiting food safety intervention programs already in place, manufacturers
could take a proactive role in monitoring product processing and packaging using
the current HACCP program as a model.
Current Barriers to Implementation
As previously discussed in Matrix 1, the greatest barrier to implementing
either enforceable standards or allowable levels for a detection program for DLCs
in food-product packaging is a lack of legal authority, given the limitations in
available data, which is due in large part to the high cost of testing and analysis.
Lower-cost alternatives (see Chapter 2) may be implemented until DLC testing
and analysis becomes more affordable. However, widespread testing and accu-
rate information on current exposure levels are needed to establish enforceable
guidelines.
DLC Exposure Reduction
Although food processing and packaging play a minor role in contributing to
DLC exposure through foods, identifying the critical points at which the entry of
DLCs into the food and food packaging process can be controlled. Setting action
levels at these points, could further reduce the DLC level in many processed
foods, which may be important if DLC exposure is found to be hazardous at
background levels.
Risk-Relationship Analysis
Ancillary Benefits. A potential ancillary benefit to food producers and pro-
cessors that may result from implementation of a DLC monitoring program in
food packaging materials is that the cost of DLC analyses would not be borne by
a single supplier, but rather would be spread over several suppliers within the
industry, thus diminishing the cost to individual companies.
Countervailing Risks. A potential countervailing risk could occur if imple-
mentation of this option increased the cost and prices of some foods. However,
the size of the production-cost increases resulting from expanded testing and
reporting, and the resultant consumer-level food price increases, would have to
be significant for this to be a strong likelihood. The committee did not view this
as probable.
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
193
Option: Require Cleaning or Washing Practices for All Vegetable, Fruit,
and Grain Crops That Potentially Had Contact with Soil
This option mandates that food processors and producers implement a uni-
form standard for washing practices for fresh vegetables, fruits, and grains used
in food products. Soil containing DLCs may adhere to vegetables, fruits, and
grains intended for human consumption. Although vegetables have not been
shown to contribute large amounts of DLCs to overall intake levels, they can
increase DLC exposure when contaminated soil is present on their surface. Thus,
washing vegetable and fruit surfaces, leaves, and stems to remove soil and peel-
ing root and waxy-coated vegetables are effective ways to reduce DLC exposure
through these foods. Washing can be incorporated into industry production prac-
tices, and can be encouraged among consumers and food preparers.
Alternate/Interim Actions
An alternative and interim action to mandated washing practices within the
food processing industry is to develop a public education and information pro-
gram to disseminate the information to consumers that they can reduce their
exposure to DLCs by washing fresh vegetables and fruits. This option should
include information on cleaning foods obtained from home gardens.
Current Barriers to Implementation
Uniform standards for washing fresh vegetables, fruits, and food grains are
not currently in place in the food-processing industry. The cost to industry of
implementing washing procedures is unknown, and a cost-impact analysis would
be needed to determine the cost feasibility of such procedures. However, washing
has been shown to be effective in reducing DLC levels in vegetables, fruits, and
grain crops (see Chapter 5), and the cost of washing may be smaller than the cost
of discarding foods that would be considered unusable due to DLC contamina-
tion.
DLC Exposure Reduction
The committee regards washing procedures as an important intermediary
step to reduce DLC exposure through vegetables, fruits, and grains. Even though
such foods have not previously been considered major contributors to DLC expo-
sure in humans, they may deserve more consideration than they have been af-
forded if DLC testing and analysis are implemented and levels are found to be
high in some of these foods.
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194
Risk-Relationship Analysis
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
Ancillary Benefits. DLCs adhere to the outside surfaces of plants, including
the skins and peels of vegetables and fruits. These compounds are carried in soil,
along with many other potential contaminants (e.g., bacteria, other organisms,
and lead) that may pose some health risk, particularly to children. Implementing
stringent cleaning and washing practices will reduce not only DLC levels on the
surfaces of vegetables, fruits, and grains, but also any bacterial or other contami-
nants on these surfaces and thus reduce exposure, particularly of young children,
to these potential hazards.
Countervailing Risks. A potential countervailing risk could occur if imple-
mentation of this option increased the cost and prices of some foods. However,
the size of the production cost increases resulting from expanded cleaning and
washing practices, and the resultant consumer-level food price increases, would
have to be significant for this to be a strong likelihood. The committee did not
view this as probable.
PATHWAY III: FOOD-CONSUMPTION PATTERNS
Given that the majority of human exposure to DLCs is from food sources,
information on the human consumption patterns of foods that may contain DLCs
is an important component of any assessment of body burden for these contami-
nants. Furthermore, an accurate analysis of food consumption by individuals in
the general population and in sensitive or highly exposed subpopulations can
serve as the basis for identifying certain foods, such as animal fats, that are major
sources of DLC exposure.
Food-consumption patterns are dynamic, and consumers tend to make spe-
cific choices within the various food groups to meet their nutritional needs.
Within a food group (e.g., the "meat and meat alternates" food group, which
contains meat, poultry, fish, dry beans, eggs, and nuts), specific foods vary greatly
in terms of their animal fat content and potential source of DLC exposure.
It is generally recognized that food-consumption patterns that include a vari-
ety of food choices are important for maintaining nutritional health. When the
selection of a food is limited, whether by choice, accessibility, or custom, the
potential to limit nutrient availability is increased, as is the probability for DLC
exposure if the food chosen is a source of DLCs. The committee identified
various dietary choices that may reduce exposure to DLCs (see Matrix 3), yet
have a minimal impact on nutrient availability or intake (see Chapter 5~.
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
Option: Increase the Availability of Low-Fat and Skim Milk in
Federal Feeding Programs Targeted to Children by Amending
the Current Act Favoring the Provision of Whole Milk in the
National School Lunch Program
195
This option would increase the availability of low-fat and skim milk to
participants in federal nutrition programs that are targeted to children, such as the
National School Lunch and School Breakfast Programs, and the Child and Adult
Care Food Program. The statute governing the National School Lunch Program
(Richard B. Russell National School Lunch Act, amended Dec. 8, 2000, § 9~2~)
states that "schools participating in the school lunch program under this Act shall
offer students a variety of fluid milk consistent with prior year preferences unless
the prior year preference for any such variety of fluid milk is less than 1 percent
of the total milk consumed at the school," which currently favors the purchase of
whole milk. Thus, this option requires the amendment of regulations that favor
the provision of whole milk to participants in the School Lunch Program.
Whole milk and full-fat dairy foods have been identified as important con-
tributors to the DLC intake of children, whereas low-fat and skim milk contain at
least as much calcium and other essential nutrients as whole milk, but have lower
levels of DLCs (see Chapter 5~. Thus, choices of low-fat milk and dairy products
can satisfy nutrient requirements and reduce exposure to DLCs.
Alternate/Interim Actions
An alternative to requiring that low-fat and skim milk be provided in federal
nutrition programs is to encourage the inclusion and increase the marketing of
low-fat and skim milk in these programs, and encourage the selection of low-fat
milk and dairy products for children over 2 years of age in the Special Supple-
mental Nutritiom Program for Women, Infants and Children. In addition, public
education and information efforts can be used to encourage parents to choose,
when appropriate, low-fat and skim milk in place of whole milk in diets of their
children above the age of 2 years.
Current Barriers to Implementation
The committee did not identify any significant direct cost barriers to pro-
gram sponsors that would result from implementation of the option to reduce
DLC exposure through foods provided in federal nutrition programs. However,
the committee recognizes that the dairy and related industries face a significant
economic issue with regard to the disposal of excess butterfat if it is removed
from milk; interfacing with relevant federal agencies for assistance may help
resolve this problem.
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196
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
Matrix 3. Intervention Options Considered to Reduce DLC
Exposure Through Pathway 111: Food-Consumption
Patterns
A. Increase the availability of low-fat and skim milk in federal feeding
programs targeted to children by amending the current act favoring the
provision of whole milk in the National School Lunch Program
Alternate/lnterim the inclusion and marketing of low-fat and skim
Actions milk in federal feeding programs targeted to children
Current Barriers to Highly feasible; possible cost barriers to the dairy industry
Implementation
DLC Exposure Reduced consumption of whole milk and increased
Reduction consumption of low-fat and skim milk, which have lower levels
of DLCs
Risk-Relationship Ancillary Benefits: Improved long-term health benefits due to
Analysis reduced consumption of saturated fats
Countervailing Risks: The nutritional status of children who
will not consume low-fat or skim milk may be at risk
B. Establish a maximum saturated fat content for meals served in schools that
participate in federal child nutrition programs
Alternate/lnterim Encourage following recommended dietary guidelines for the
Actions maximum saturated fat content for individual meals served in
schools that participate in federal feeding programs, while
determining the feasibility of setting maximum limits on
saturated fats in individual meals
DLC Exposure Reduction
Based on current evidence for DLC exposure through whole milk and full-fat
dairy products (see Chapter 5), the committee expects that reduced consumption
of these products will decrease the DLC intake levels in children who consume
them. The commissioned analysis of DLC exposure through foods further indi-
cates that, especially in young children over 2 years of age and girls under 19
years of age, consuming low-fat or skim rather than whole milk and choosing
low-fat versions of other dairy foods will reduce their DLC intake (see Chap-
ter 5~.
Risk-Relationship Analysis
Ancillary Benefits. There are no clear nutritional benefits from eating foods
high in saturated fats that would not be obtained by eating lower-fat versions of
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
197
Current Barriers to High feasibility if recommendations are accepted and
Implementation implemented, but cost may be high, especially to food
industries
DLC Exposure Reduced exposure to DLCs present in animal fats
Reduction
Risk-Relationship Ancillary Benefits: Changed food-consumption patterns away
Analysis from the consumption of saturated fats from animal-based
foods will decrease the risk for some chronic diseases
Countervailing Risks: The nutritional status of some children
who will not consume foods low in saturated fats may be at
risk
C. Promote changes in dietary-consumption patterns of the general
population that more closely conform to recommendations from the Dietary
Guidelines for Americans to reduce the consumption of foods high in
saturated fats
Alternate/lnterim Implement revisions to the federally sponsored dietary
Actions guidelines
Current Barriers to High feasibility if recommendations are accepted and
Implementation implemented by the public
DLC Exposure Reduced exposure to DLCs through foods containing animal
Reduction fats
Risk Relationship Ancillary Benefits: Changed food-consumption patterns away
Analysis from the consumption of saturated fats from animal-based
foods will decrease the risk for some chronic diseases
Countervailing Risks: Dietary recommendations to increase
fish consumption are not conducive to reducing DLC intake
the same foods. If young children, both male and female, decrease their intake of
whole milk and full-fat dairy products, they will consume lower levels of satu-
rated fats, while consuming the same levels of calcium, vitamin D, and other
important nutrients. This modification will likely have the net benefit of decreas-
ing the risk for certain chronic diseases that are associated with consuming high
levels of saturated fats (see Chapter 5~.
Countervailing Risks. A possible countervailing risk that could arise from
offering low-fat and skim milk in place of whole milk to children is that they
could choose to not drink any milk, which could place them at nutritional risk.
However, a risk analysis would have to be performed for this scenario in order to
verify this outcome.
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DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
Option: Establish a Maximum Saturated Fat Content for Meals Served in
Schools That Participate in Federal Child Nutrition Programs
This option would, within the current regulatory framework, establish a
maximum allowable content for saturated fats in individual meals served through
federal child nutrition programs, including the School Lunch and School Break-
fast Programs and the Child and Adult Care Food Program.
There is currently no standard for saturated fat levels for individual meals in
these programs. There is, however, a requirement that meals averaged over a
week contain less than 10 percent of total calories from saturated fats (School
Meals Initiative for Healthy Children, 7 C.F.R. 20~. Since these standards were
adopted, reductions in the saturated fat content of school meals have occurred,
although the goal for saturated fat to be less than 10 percent of total calories has
not been met.
Alternate/Interim Actions
An alternate or interim action is to encourage compliance with recommended
dietary guidelines through public education and information programs that will
inform parents of the benefits of providing foods low in saturated fats to their
children, while determining the feasibility of setting maximum limits on satu-
rated fat in school breakfast and lunch meals.
Current Barriers to Implementation
Children who are not accustomed to consuming foods low in saturated fats
may not initially accept such foods offered through federal nutrition programs. If
the meals served in a program are the primary source of nutrients for children,
their nutritional intakes are affected by the food choices they make. There are,
however, a wide variety of foods low in saturated fat that can be made available
to children. Thus, although this option will change the variety of foods offered, it
will not necessarily limit it. One barrier to implementation of this option is likely
to be poor acceptance of foods lower in saturated fats, particularly if they are not
presented in an attractive and appealing way.
Current studies suggest that implementing reductions in the saturated fat
content of school meals can be accomplished at minimal cost to consumers.
However, because the economic feasibility of reducing the saturated fat content
of school meals, and the impact of other factors, such as reduced acceptance by
children and increased costs to the food industry have not been established, this is
another barrier to implementation.
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
DLC Exposure Reduction
199
DLCs are found primarily in animal fats. Additionally, these fats are also the
primary source of saturated fats in the American diet. By reducing the availability
of foods high in saturated fats, exposure to DLCs that may be present will also be
reduced. Since this option is targeted to young children, their exposure to DLCs
through these foods is expected to decrease. As previously stated, the committee
believes that DLC exposure reduction is important in young children, particularly
girls, so that they may enter their reproductive years with lower DLC body
burdens.
Risk-Relationship Analysis
Ancillary Benefits. Research has shown that reducing the consumption of
foods high in saturated fats is associated with the reduced risk for many chronic
diseases, including heart disease and cancer. Therefore, long-term health benefits
would be expected to result from reducing saturated fat intake beginning in
childhood.
Countervailing Risks. Children who do not accept foods lower in saturated
fats may not have adequate nutrient intakes and may be at increased nutritional
risk.
Option: Promote Changes in Dietary-Consumption Patterns of the
General Population That More Closely Conform to Recommendations
from the Dietary Guidelines for Americans to Reduce the Consumption of
Foods High in Saturated Fats
This option recommends that the federal sponsors of the U.S. Dietary Guide-
lines institute public education and information dissemination campaigns and
actively promote compliance with the recommendations of the Guidelines, par-
ticularly those that advise the decreased intake of foods high in saturated fats.
Although the U.S. Dietary Guidelines are available through publications and
informational websites, current promotional efforts by federal sponsors are insuf-
ficient.
The dietary recommendations and associated educational tools for the gen-
eral population that are consistent with reducing DLC exposure by reducing
animal-fat intake include the Dietary Guidelines for Americans, last revised in
2000; the Food Guide Pyramid, based on the Dietary Guidelines; the dietary
findings of the Institute of Medicine in the recently released report on Dietary
Reference for Intakes Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Choles-
terol, Protein, and Amino Acids; and the recommendations of the American Heart
Association (AHA). Although these documents do not provide specific guidance
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200
DIOXINS AND DIOXIN-LIKE COMPOUNDS IN THE FOOD SUPPLY
regarding foods high in DLCs, their recommendations to reduce intake of animal
fat, the primary source of saturated fats, will result in a reduction in exposure to
DLCs. As discussed in Chapter 5, dietary surveys, such as the Continuing Survey
of Food Intakes by Individuals and the National Health and Nutrition Examina-
tion Survey have shown a trend of decreasing saturated fat intake in the general
population, and the committee believes this trend should be encouraged to con-
tinue. In addition, the recommendation to reduce intake of saturated fats is in
keeping with current national policies for good nutrition and health. Compliance
with this recommendation does not require a reduction in protein intake; rather, it
is a recommendation to trim visible fats from animal foods. Thus, the committee
believes that compliance with this recommendation will not place consumers at
increased nutritional risk and would likely reduce the risk for chronic disease.
Alternate/Interim Actions
An alternate action that may be taken is to revise the content of the U.S.
Dietary Guidelines to include a food safety component that would recommend
low-fat, but nutritionally equivalent, alternate choices to foods that are high in
saturated fats as a way to reduce DLC exposure.
Current Barriers to Implementation
Since compliance with dietary recommendations is not mandatory, the suc-
cess of such programs as a means to reduce DLC exposure depends entirely on
their acceptance by the population. Educational campaigns and other promotional
efforts can be undertaken to enhance public awareness and improve compliance
with dietary recommendations. However, the committee recognizes there is un-
certainty about the impact of educational programs on behavioral changes.
DLC Exposure Reduction
Adherence to dietary recommendations to reduce intake of saturated fats and
animal fats is expected to, over a period of years, reduce DLC body burdens.
Risk-Relationship Analysis
Ancillary Benefits. In addition to reducing DLC exposures, there are con-
comitant ancillary benefits to overall health from compliance with recommenda-
tions to reduce total and saturated fat intake, such as the reduced risk for chronic
disease, especially heart disease.
Countervailing Risks. The dietary recommendation in the U.S. Dietary
Guidelines and the AHA recommendations that is not conducive to both reducing
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POLICY OPTIONS TO REDUCE EXPOSURE TO DIOXINS
201
DLC intake and improving health outcome is that of fish consumption. As dis-
cussed in Chapter 5, certain fish, including salmon and catfish, have been found
in some cases to contain relatively high levels of DLCs, although these vary by
source, location, and feeding exposure. As with other foods, the DLC content of
fish closely parallels the fat content. Unfortunately, the fatty component of fish
that is the source of beneficial omega-3 fatty acids is also the component of fish
where DLCs accumulate.
To some extent, DLC concentrations in fish differ depending not only on the
species, but also on the geographic region in which they are found, because some
areas have greater environmental contamination than others. Nevertheless, over-
all wide variability is seen in analytical data reported for DLC levels in many
foods, including fish, which increases the level of uncertainty and decreases the
reliability of measures used for trend analysis. This level of uncertainty increases
the difficulty of making reliable recommendations to reduce exposure to DLCs,
particularly when it may be to the detriment of health benefits derived from
certain foods.
Chapter 8 presents the committee's recommendations to reduce DLC expo-
sure through foods from the array of options presented in this chapter.
Representative terms from entire chapter:
dlc levels
