APPENDIX B
Measures of Exposure to Fluoride in the United States: Supplementary Information

U.S. DATA ON ARTIFICIAL AND NATURAL FLUORIDE IN DRINKING WATER

The recommended “optimal” fluoride concentrations for community public water supply systems and school public water supply systems are shown in Table B-1. Both sets of recommendations are based on the “annual average of maximum daily air temperatures” (CDC 1995, based on two studies in the 1950s). Table B-2 provides the approximate number of persons receiving artificially fluoridated public water in 1992, by fluoride concentration. In practice, most states seem to use a single fluoride concentration for the whole state. Figure B-1 shows the fluoride concentration by state with respect to annual average temperature for that state over the period 1971-2000. Table B-3 presents the approximate number of persons receiving naturally fluoridated public water in 1992, by fluoride concentration.

The number of persons served with public water supplies exceeding 4 milligrams (mg) of fluoride per liter (L) is expected to be substantially lower now than in 1992. For example, South Carolina, which had more than half of the persons in that category in 1992 (Table B-3), now has only occasional violations of the maximum contaminant level (MCL) (e.g., two water systems with 10 violations in calendar year 2003; SCDHEC 20041). On the other hand, a recent news article indicates that some areas in Virginia

1

See also local drinking water information by state at http://www.epa.gov/safewater/dwinfo.htm.



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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards APPENDIX B Measures of Exposure to Fluoride in the United States: Supplementary Information U.S. DATA ON ARTIFICIAL AND NATURAL FLUORIDE IN DRINKING WATER The recommended “optimal” fluoride concentrations for community public water supply systems and school public water supply systems are shown in Table B-1. Both sets of recommendations are based on the “annual average of maximum daily air temperatures” (CDC 1995, based on two studies in the 1950s). Table B-2 provides the approximate number of persons receiving artificially fluoridated public water in 1992, by fluoride concentration. In practice, most states seem to use a single fluoride concentration for the whole state. Figure B-1 shows the fluoride concentration by state with respect to annual average temperature for that state over the period 1971-2000. Table B-3 presents the approximate number of persons receiving naturally fluoridated public water in 1992, by fluoride concentration. The number of persons served with public water supplies exceeding 4 milligrams (mg) of fluoride per liter (L) is expected to be substantially lower now than in 1992. For example, South Carolina, which had more than half of the persons in that category in 1992 (Table B-3), now has only occasional violations of the maximum contaminant level (MCL) (e.g., two water systems with 10 violations in calendar year 2003; SCDHEC 20041). On the other hand, a recent news article indicates that some areas in Virginia 1 See also local drinking water information by state at http://www.epa.gov/safewater/dwinfo.htm.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-1 Recommended Optimal Fluoride Concentrations for Public Water Supply Systems Annual Average of Maximum Daily Air Temperaturesa Recommended Fluoride Concentrations, mg/L °F °C Community Water Systems School Water Systemsb 50.0-53.7 10.0-12.0 1.2 5.4 53.8-58.3 12.1-14.6 1.1 5.0 58.4-63.8 14.7-17.7 1.0 4.5 63.9-70.6 17.8-21.4 0.9 4.1 70.7-79.2 21.5-26.2 0.8 3.6 79.3-90.5 26.3-32.5 0.7 3.2 aBased on temperature data obtained for a minimum of 5 years. bBased on 4.5 times the optimal fluoride level for communities. School water fluoridation is recommended only when the school has its own source of water and is not connected to a community water system. Several other criteria are also considered; for example, if >25% of the children attending the school already receive optimally fluoridated water at home, the school’s water should not be fluoridated. SOURCE: CDC 1995. are still served by water systems with fluoride exceeding 4 mg/L (Hirschauer 2004). Miller-Ihli et al. (2003) reported on fluoride concentrations in water samples collected in 1999 from 24 locations nationwide; these locations were expected to provide nationally representative samples for the National Food and Nutrient Analysis Program.2 Not unexpectedly, their findings indicate a bimodal distribution of fluoride concentrations in public drinking water: either water was fluoridated at approximately 1 mg/L or it was not fluoridated, with concentrations bordering on undetectable. WATER INGESTION AND FLUORIDE INTAKES Tables B-4 to B-7 summarize recent estimates by the U.S. Environmental Protection Agency (EPA) of the mean and selected percentiles of water ingestion by source (community supplies, bottled water, “other” sources, and all sources combined) and subpopulation (EPA 2000a); Tables B-8 and B-9 2 Miller-Ihli et al. (2003) reported that 40% of the samples were fluoridated and suggested that, rather than using an average fluoride concentration for the country, an individual should be assumed to have a 40% probability of ingesting fluoridated water and a 60% probability of ingesting nonfluoridated water. However, CDC (2002a) estimates that about two-thirds of the U.S. population served by public water supplies receives fluoridated water. Thus, the sampling reported by Miller-Ihli et al. was probably not sufficiently representative on a population-weighted basis.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-2 Population Sizes by Level of Artificial Fluoridation in 1992 Fluoride, mg/L Number of Statesa Population Percentage States 0.7 1 149,290 0.11 Hawaii 0.7-0.9 1 8,014,583 5.88 Texas 0.7-1.0 1 1,282,425 0.94 Arizona 0.8 4 12,886,396 9.46 Florida, Louisiana, Oklahoma, South Carolina 0.8-1.0 1 432,700 0.32 Delaware 0.9 2 7,177,525 5.27 Kentucky,b Virginiac 0.9-1.2 1 1,921,525 1.41 Colorado 1.0 29 93,060,026 68.30 Alabama, California, Connecticut, District of Columbia, Georgia, Idaho, Illinois, Indiana,c Kansas, Maryland, Massachusetts, Michigan, Mississippi, Missouri, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina,c Ohio, Oregon, Pennsylvania, Rhode Island, Tennessee, Utah, Washington, West Virginia,c Wisconsin 1.0-1.1 2 1,931,337 1.42 Iowa, Wyoming 1.0-1.2 2 214,865 0.16 Montana, New Hampshire 1.1 1 233,447 0.17 Vermontd 1.2 5 5,026,243 3.69 Alaska, Maine, Minnesota,e North Dakota, South Dakota No dataf 2 3,911,884 2.87 Arkansas, Puerto Rico Total 52 136,242,246 100   aIncludes the 50 states, the District of Columbia, and Puerto Rico. bA few small water supplies have artificial fluoride concentrations of 4.0 mg/L. cA few small water supplies have artificial fluoride concentrations of 4.5 mg/L. dA few small water supplies have artificial fluoride concentrations of 4.9 mg/L. eA few small water supplies have artificial fluoride concentrations of 5.4 mg/L. fData for Arkansas were not provided (the table for Arkansas contained a duplication of the Alaska data). The water fluoridation data were not provided for Puerto Rico. SOURCE: CDC 1993. give the corresponding estimates for consumption of community water or all water as a function of body weight. The data in Tables B-4 through B-9 are for those persons who actually consume water from the indicated source, rather than per capita estimates for the entire population. Estimates include plain (noncarbonated) drinking water and indirect water (water added to foods and beverages during preparation at home or by local food service establishments). Water in processed foods (commercial water) or naturally contained in foods (biological water) was not included.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards FIGURE B-1 Level of artificial fluoridation in 1992 by state (Table B-2; CDC 1993) versus area-weighted annual average temperature (°F) for that state over the period 1971-2000 (NCDC 2002a). Temperature for the District of Columbia is for Climate District 4 of the state of Maryland (NCDC 2002b). States with a range of artificial fluoride levels (Arizona, Colorado, Delaware, Iowa, Montana, New Hampshire, Texas, and Wyoming) are included at each relevant fluoride level. Arkansas and Puerto Rico are not included because of the lack of information on fluoride levels. Thin line indicates the “recommended optimal fluoride levels” for the given range of “annual average of maximum daily air temperatures” (emphasis added; Table B-1; CDC 1995). EPA’s estimates are based on U.S. Department of Agriculture surveys taken in 1994, 1995, and 1996 of food ingestion data for two nonconsecutive days for a sample of more than 15,000 individuals in the 50 states and the District of Columbia selected to represent the entire U.S. population based on 1990 census data (EPA 2000a). (An additional survey of children in 1998 was included in the estimates used in Chapter 2.) Because these estimates were developed for the purpose of estimating people’s exposures to substances in drinking water and also are based on relatively recent data,

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-3 Population Sizes by Level of Natural Fluoridation in 1992     Reported Level of Natural Fluoride, mg/L   Statea Reported Range, mg/L ≤1.2 1.3-1.9 2.0-3.9 ≥4.0 Not givenb Reported Totalc Alabama 0.7-3.6 27,368 25,195 6,827 0 — 54,283 Arizona 0.7-7.4 242,309 63,132 39,259 516 — 345,266 Arkansas NAd — — — — — 17,239 California 0.7-3.5 389,715 24,583 500 0 — 414,798 Colorado 0.1-11.2 363,905 75,755 361,969 1,926 — 801,224 Connecticut 0.7-1.9 870 160 0 0 — 1,030 Delaware 0.6-0.9 7,171 0 0 0 — 7,171 Florida 0.5-3.6 890,443 37,435 1,227 0 — 929,105 Georgia 0.7-2.0 16,039 878 1,200 0 7,475 25,592 Hawaii 0.7 354 0 0 0 — 354 Idaho 0.6-15.9 293,127 8,275 2,650 500 — 304,552 Illinois 0.7-4.0 291,600 91,237 56,481 500 6,658 446,050 Indiana 0.7-4.4 177,890 36,254 5,541 5,790 31,928 264,233 Iowa 0.7-7.0 186,936 90,182 28,484 1,445 — 302,652 Kansas 0.5-2.6 81,884 14,958 22,846 0 41,558 161,515 Kentucky NAe 0 0 0 0 1,899 1,899 Louisiana 0.7-3.8 302,520 44,787 12,599 0 — 357,210 Maryland 0.3-5.1 36,583 11,705 100 225 — 48,613 Massachusetts 1.0-1.1 122 0 0 0 — 122 Michigan 0.7-1.9 114,605 9,968 0 0 — 124,623 Minnesota 0.7-3.2 2,386 908 367 0 — 4,000 Mississippi 0.8-3.5 93,120 9,965 1,560 0 — 104,645 Missouri 0.7-5.0 74,412 58,168 16,906 180 — 143,603 Montana 0.1-7.3 85,452 3,923 7,171 1,814 492 82,985 Nebraska 0.3-1.4 31,246 4,352 0 0 — 35,598 Nevada 0.5-2.6 16,440 3,628 5,187 0 — 25,255 New Hampshire 1.0-3.9 12,612 3,749 11,190 0 — 27,551

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards New Jersey 0.7-2.5 32,344 56,450 24,651 0 — 113,445 New Mexico 0.7-13 178,754 45,619 58,556 4,295 261 287,485 New York NAe 0 0 0 0 1,536 1,216 North Carolina 0.0-2.7 0 7,200 325 0 183,076 190,601 North Dakota 0.5-7.0 5,205 6,002 6,024 3,793 — 20,421 Ohio 0.8-2.8 131,963 104,558 13,450 0 1,010 249,755 Oklahoma 0.7-12.0 62,353 20,803 8,966 18,895 — 111,017 Oregon 0.7-2.4 39,865 2,320 680 0 — 42,865 South Carolina 0.1-5.9 62,924 27,968 190,430 105,618 — 378,995 South Dakota 0.7-6.0 10,097 14,053 41,038 692 — 37,758 Texas 0.7-8.8 2,234,504 426,341 233,326 36,863 25,200 2,955,395 Utah 0.7-2.0 8,240 2,560 0 0 — 10,800 Virginia 0.7-6.3 8,418 11,423 207,924 18,726 408 246,694 Washington 0.7-2.7 54,460 3,117 4,916 0 — 62,493 West Virginia 1.2 659 0 0 0 — 659 Wisconsin 0.7-2.7 90,713 36,570 50,140 0 — 174,850 Wyoming 0.7-4.5 14,694 21,984 2,144 120 — 38,942 Totals   6,674,302 1,406,165 1,424,634 201,898 301,501 9,954,559 aAlaska, the District of Columbia, Maine, Pennsylvania, Rhode Island, Tennessee, and Vermont reported no water systems with natural fluoridation. bReported as 0.0 or some other number suspected to be a misprint. cTotal given in the summary table for each state. Because of apparent internal inconsistencies, the numbers in the preceding columns do not necessarily give the same total. dData for Arkansas were not provided (the table for Arkansas contained a duplication of the Alaska data). eReported as 0.0 for all systems with natural fluoride. SOURCE: CDC 1993.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-4 Estimated Average Daily Water Ingestion (mL/day) from Community Sources During 1994-1996, by People Who Consume Water from Community Sources Population Mean 50th Percentile 90th Percentile 95th Percentile 99th Percentile Sample Size Population All consumers 1,000 785 2,069 2,600 4,273 14,012 242,641,675 <0.5 year 529 543 943 1,064 1,366 111 1,062,136 0.5-0.9 year 502 465 950 1,122 1,529 135 1,449,698 1-3 years 351 267 719 952 1,387 1,625 10,934,001 4-6 years 454 363 940 1,213 1,985 1,110 11,586,632 7-10 years 485 377 995 1,241 1,999 884 14,347,058 11-14 years 641 473 1,415 1,742 2,564 759 14,437,898 15-19 years 817 603 1,669 2,159 3,863 777 16,735,467 20-24 years 1,033 711 2,175 3,082 5,356 644 17,658,027 25-54 years 1,171 965 2,326 2,926 4,735 4,599 106,779,569 55-64 years 1,242 1,111 2,297 2,721 4,222 1,410 19,484,112 ≥ 65 years 1,242 1,149 2,190 2,604 3,668 1,958 28,167,077 Males (all) 1,052 814 2,164 2,733 4,616 7,082 118,665,763 <1 year 462 441 881 1,121 1,281 118 1,191,526 1-10 years 444 355 934 1,155 1,731 1,812 18,847,070 11-19 years 828 595 1,673 2,058 3,984 768 15,923,625 ≥ 20 years 1,242 1,038 2,387 3,016 4,939 4,384 82,703,542 Females (all) 951 747 2,005 2,482 3,863 6,930 123,975,912 <1 year 560 542 967 1,122 1,584 128 1,320,308 1-10 years 426 329 940 1,109 2,014 1,807 18,020,621 11-19 years 638 457 1,382 1,774 2,598 768 15,249,740 ≥ 20 years 1,116 943 2,165 2,711 4,268 4,227 89,385,243 Lactating women 1,665 1,646 2,959 3,588 4,098 34 971,057 Pregnant women 872 553 1,844 2,588 3,448 65 1,645,565 Women aged 15-44 years 984 756 2,044 2,722 4,397 2,176 55,251,477 SOURCE: EPA 2000a.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-5 Estimated Average Daily Water Ingestion (mL/day) from Bottled Water During 1994-1996, by People Who Consume Bottled Water Population Mean 50th Percentile 90th Percentile 95th Percentile 99th Percentile Sample Size Population All consumers 737 532 1,568 1,967 3,316 3,078 57,316,806 <0.5 year 411 349 896 951 1,193 51 538,267 0.5-0.9 year 437 361 802 808 1,578 37 456,103 1-3 years 302 232 649 819 1,175 368 2,532,201 4-6 years 390 315 794 922 1,319 213 2,336,873 7-10 years 416 323 828 985 1,767 164 2,808,756 11-14 years 538 361 1,099 1,420 2,192 148 2,896,893 15-19 years 665 468 1,503 1,777 3,149 163 3,528,434 20-24 years 786 532 1,640 2,343 3,126 179 5,089,216 25-54 years 822 621 1,773 1,981 3,786 1,174 28,487,354 55-64 years 860 685 1,833 2,306 2,839 279 3,987,578 ≥ 65 years 910 785 1,766 2,074 2,548 302 4,655,131 Males (all) 749 523 1,626 2,097 3,781 1,505 26,298,392 <1 year 414 317 805 1,012 1,397 48 575,019 1-10 years 365 266 767 847 1,685 376 3,755,220 11-19 years 682 464 1,423 1,822 2,802 144 2,969,950 ≥ 20 years 845 592 1,774 2,303 3,855 937 18,998,203 Females (all) 727 532 1,542 1,893 3,031 1,573 31,018,414 <1 year 436 428 895 896 1,301 40 419,351 1-10 years 375 289 765 993 1,347 369 3,922,610 11-19 years 544 357 1,116 1,537 3,143 167 3,455,377 ≥ 20 years 819 690 1,747 1,975 3,060 997 23,221,076 Lactating women 749 608 1,144 1,223 1,286 7 278,308 Pregnant women 891 683 1,910 1,957 2,198 27 698,645 Women aged 15-44 years 766 592 1,598 1,922 3,093 611 16,279,438 SOURCE: EPA 2000a.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-6 Estimated Average Daily Water Ingestion (mL/day) from Other Sources (e.g., Wells and Cisterns) During 1994-1996, by People Who Consume Water from Those Sources Population Mean 50th Percentile 90th Percentile 95th Percentile 99th Percentile Sample Size Population All consumers 965 739 1,971 2,475 3,820 2,129 34,693,744 <0.5 year 306 188 637 754 878 15 117,444 0.5-0.9 year 265 172 552 560 567 14 198,639 1-3 years 347 291 710 761 1,190 206 1,243,498 4-6 years 390 285 778 1,057 1,332 137 1,382,002 7-10 years 485 399 992 1,093 1,623 134 2,121,832 11-14 years 733 553 1,561 1,884 3,086 121 2,243,452 15-19 years 587 395 1,221 1,721 2,409 109 2,372,842 20-24 years 640 472 1,305 1,648 1,937 67 1,809,825 25-54 years 1,124 917 2,175 2,834 4,728 731 15,480,754 55-64 years 1,276 1,110 2,365 2,916 5,152 272 3,504,576 ≥65 years 1,259 1,188 2,136 2,470 3,707 323 4,218,880 Males (all) 1,031 785 2,107 2,821 4,734 1,155 17,880,530 <1 year 243 148 554 567 773 16 198,829 1-10 years 426 320 884 1,077 1,630 259 2,566,652 11-19 years 702 564 1,366 1,753 2,787 103 2,011,715 ≥20 years 1,212 1,001 2,286 3,017 4,883 777 13,103,334 Females (all) 894 710 1,826 2,225 3,035 974 16,813,214 <1 year 344 256 537 579 759 13 117,254 1-10 years 416 352 865 1,039 1,165 218 2,180,680 11-19 years 624 406 1,394 1,873 2,489 127 2,604,579 ≥ 20 years 1,046 941 1,925 2,371 3,123 616 11,910,701 Lactating women 1,248 915 2,148 2,410 2,620 7 182,414 Pregnant women 1,066 660 1,676 1,807 3,374 7 168,433 Women aged 15-44 years 904 666 1,863 2,319 3,056 283 6,759,992 SOURCE: EPA 2000a.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-7 Estimated Average Daily Water Ingestion (mL/day) from All Sources During 1994-1996 by Consumers of Water Population Mean 50th Percentile 90th Percentile 95th Percentile 99th Percentile Sample Size Population All consumers 1,241 1,045 2,345 2,922 4,808 15,172 259,972,235 <0.5 year 544 545 947 1,078 1,365 156 1,507,727 0.5-0.9 year 580 563 1,130 1,273 1,672 154 1,732,993 1-3 years 422 351 807 993 1,393 1,814 12,143,483 4-6 years 548 468 1,019 1,268 2,031 1,193 12,438,322 7-10 years 608 514 1,131 1,425 2,172 937 15,248,676 11-14 years 815 651 1,625 1,962 3,033 812 15,504,627 15-19 years 1,006 776 1,897 2,414 4,027 814 17,697,092 20-24 years 1,283 1,013 2,508 3,632 5,801 678 18,544,787 25-54 years 1,486 1,273 2,638 3,337 5,259 4,906 113,011,204 55-64 years 1,532 1,378 2,557 2,999 4,395 1,541 21,145,387 ≥65 years 1,453 1,345 2,324 2,708 3,750 2,167 30,997,937 Males (all) 1,300 1,070 2,483 3,149 5,212 7,689 126,998,276 <1 year 549 538 1,121 1,278 1,567 151 1,560,310 1-10 years 536 451 1,024 1,254 1,817 1,993 20,495,833 11-19 years 1,001 761 1,898 2,434 4,011 809 16,887,932 ≥ 20 years 1,549 1,331 2,740 3,524 5,526 4,736 88,054,201 Females (all) 1,185 1,021 2,221 2,703 4,252 7,483 132,973,959 <1 year 577 559 950 1,131 1,654 159 1,680,410 1-10 years 528 445 993 1,226 2,035 1,951 19,334,648 11-19 years 830 664 1,652 1,955 3,083 817 16,313,787 ≥20 years 1,389 1,221 2,416 2,928 4,512 4,556 95,645,114 Lactating women 1,806 1,498 3,021 3,767 4,024 41 1,171,868 Pregnant women 1,318 1,228 2,339 2,674 3,557 70 1,751,888 Women aged 15-44 years 1,265 1,065 2,366 2,952 4,821 2,314 58,549,659 SOURCE: EPA 2000a.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-8 Estimated Average Daily Water Ingestion (mL/kg of Body Weight per Day) from Community Sources during 1994-1996, by People Who Consume Water from Community Sources Population Mean 50th Percentile 90th Percentile 95th Percentile 99th Percentile Sample Size Population All consumers 17 13 33 44 79 13,593 236,742,834 <0.5 year 88 85 169 204 240 106 1,034,566 0.5-0.9 year 56 52 116 127 170 128 1,405,128 1-3 years 26 20 53 68 112 1,548 10,417,368 4-6 years 23 18 45 65 95 1,025 10,751,616 7-10 years 16 12 33 39 60 820 13,427,986 11-14 years 13 10 27 36 54 736 14,102,256 15-19 years 12 9 26 32 62 771 16,646,551 20-24 years 15 11 31 39 80 637 17,426,127 25-54 years 16 13 32 40 65 4,512 104,816,948 55-64 years 17 14 32 38 58 1,383 19,011,778 ≥65 years 18 16 32 37 53 1,927 27,702,510 Males (all) 16 13 32 43 81 6,935 117,076,195 <1 year 66 60 139 175 235 115 1,180,289 1-10 years 21 16 43 55 87 1,705 17,865,064 11-19 years 14 10 27 38 67 755 15,717,364 ≥ 20 years 15 13 30 38 62 4,360 82,313,478 Females (all) 17 14 35 45 77 6,658 119,666,639 <1 year 72 69 139 169 203 119 1,259,405 1-10 years 21 17 45 61 98 1,688 16,731,906 11-19 years 12 9 26 32 48 752 15,031,443 ≥20 years 17 14 33 41 63 4,099 86,643,885 Lactating women 26 20 54 55 57 33 940,375 Pregnant women 14 9   43 47 65 1,645,565 Women aged 15-44 years 15 12 32 39 66 2,126 54,000,618 SOURCE: EPA 2000a.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards they are appropriate for the present purpose of estimating the range of current exposures to fluoride. These estimates are based on a 2-day average, whereas for fluoride exposure, long-term averages of intake are usually more important. However, given the size of the population sampled, the likelihood that the entire sample represents days of unusually high or unusually low water intake is small. Thus, these values are considered reasonable indicators both of typical water consumption and of the likely range of water consumption from various sources on a long-term basis. However, they should not be used by themselves to estimate the number of individuals or percentage of the population that consumes a given amount of water on a long-term basis, especially not at the extremes of the range. Water intakes at the low end are not of major importance for the present report, and water intakes at the high end are considered separately (Chapter 2), with additional information beyond what is provided by EPA. It may be helpful to compare the water intakes (all sources, Table B-7) with values for adequate intake3 (AI) of water recently published by the Institute of Medicine (IOM 2004; Table B-10). The AI for total water (drinking water, other beverages, and moisture contained in food) is set “to prevent deleterious, primarily acute, effects of dehydration, which include metabolic and functional abnormalities” (IOM 2004). “Given the extreme variability in water needs which are not solely based on differences in metabolism, but also in environmental conditions and activity, there is not a single level of water intake that would ensure adequate hydration and optimal health for half4 of all apparently healthy persons in all environmental conditions” (IOM 2004). The AI for total water is based on the median total water intake from U.S. survey data (NHANES III, 1988-1994; described by IOM 2004). Daily consumption below the AI is not necessarily a concern “because a wide range of intakes is compatible with normal hydration. Higher intakes of total water will be required for those who are physically active or who are exposed to [a] hot environment” (IOM 2004). For the intake values shown in Table B-10, approximately 80% of the intake comes from drinking water and other beverages (including caffeinated and alcoholic beverages). Use of bottled water in the United States has at least doubled since 1990 (Grossman 2002), suggesting that more people use bottled water now than in 1994-1996 and/or that individuals use more bottled water per person. 3 “Adequate intake” is defined as “the recommended average daily intake level based on observed or experimentally determined approximations or estimates of nutrient intake by a group (or groups) of apparently healthy people that are assumed to be adequate—used when an RDA [recommended dietary allowance] cannot be determined” (IOM 2004). 4 The estimated average requirement (EAR) on which a recommended dietary allowance is based is defined as “the average daily nutrient intake level estimated to meet the requirement of half the healthy individuals in a particular life stage and gender group” (IOM 2004).

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-10 Adequate Intake Values (L/day) for Total Water   Males Females Group From Foods From Beverages Total Water From Foods From Beverages Total Water 0-6 months 0 0.7 0.7 0 0.7 0.7 7-12 months 0.2 0.6 0.8 0.2 0.6 0.8 1-3 years 0.4 0.9 1.3 0.4 0.9 1.3 4-8 years 0.5 1.2 1.7 0.5 1.2 1.7 9-13 years 0.6 1.8 2.4 0.5 1.6 2.1 14-18 years 0.7 2.6 3.3 0.5 1.8 2.3 >19 years 0.7 3.0 3.7 0.5 2.2 2.7 Pregnancya — — — 0.7 2.3 3.0 Lactationa — — — 0.7 3.1 3.8 aWomen aged 14-50 years. SOURCE: IOM 2004. However, total water consumption per person from all sources combined probably has not changed substantially. Information for a few groups in the tables (children < 1 year of age, pregnant and lactating women) is based on relatively small sample sizes, and the confidence to be placed in specific percentile values is therefore lower. Sample sizes for some other population subgroups of potential interest (e.g., Native Americans with traditional lifestyles, people in hot climates, people with high physical activity, people with certain medical conditions) were not large enough to evaluate intake by members of the subgroup, although some people from those groups are included in the overall sample (EPA 2000a). Tables B-11 to B-14 summarize fluoride intakes that would result from ingestion of community water (for the mean, 90th, 95th, and 99th percentiles of consumption estimated by EPA) at various levels of water fluoride (“optimal” fluoridation levels of 0.7, 1.0, or 1.2 mg/L, and the present secondary MCL [SMCL] and MCL of 2 and 4 mg/L, respectively). The SMCL and MCL are included for purposes of comparison; most people in the Unites States do not drink water with those fluoride levels. An average consumer below the age of 6 months would have an intake of 0.06-0.1 mg/kg/day from fluoridated water (0.7-1.2 mg/L), whereas an adult would ingest approximately 0.01-0.02 mg/kg/day. Individuals at the upper levels of water intake from EPA’s estimates (Table B-14) could have fluoride intakes in excess of 1 mg/day at the lowest levels of fluoridation up to about 6 mg/day for some adults, depending on age and level of water fluoridation. Persons in the high-water-intake groups described above could have even higher intakes.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-11 Estimated Intake of Fluoride from Community Water for Average Consumersa     Fluoride Level   Water Intake, mL/day 0.7 mg/L 1 mg/L 1.2 mg/L 2 mg/L 4 mg/L Population Intake, mg/day All consumers 1,000 0.70 1.00 1.20 2.00 4.00 <0.5 year 529 0.37 0.53 0.63 1.06 2.12 0.5-0.9 year 502 0.35 0.50 0.60 1.00 2.01 1-3 years 351 0.25 0.35 0.42 0.70 1.40 4-6 years 454 0.32 0.45 0.54 0.91 1.82 7-10 years 485 0.34 0.49 0.58 0.97 1.94 11-14 years 641 0.45 0.64 0.77 1.28 2.56 15-19 years 817 0.57 0.82 0.98 1.63 3.27 20-24 years 1,033 0.72 1.03 1.24 2.07 4.13 25-54 years 1,171 0.82 1.17 1.41 2.34 4.68 55-64 years 1,242 0.87 1.24 1.49 2.48 4.97 ≥65 years 1,242 0.87 1.24 1.49 2.48 4.97   Water Intake, mL/kg/day Intake, mg per kg body weight/day All consumers 17 0.012 0.017 0.020 0.034 0.068 <0.5 year 88 0.062 0.088 0.106 0.176 0.352 0.5-0.9 year 56 0.039 0.056 0.067 0.112 0.224 1-3 years 26 0.018 0.026 0.031 0.052 0.104 4-6 years 23 0.016 0.023 0.028 0.046 0.092 7-10 years 16 0.011 0.016 0.019 0.032 0.064 11-14 years 13 0.009 0.013 0.016 0.026 0.052 15-19 years 12 0.008 0.012 0.014 0.024 0.048 20-24 years 15 0.011 0.015 0.018 0.030 0.060 25-54 years 16 0.011 0.016 0.019 0.032 0.064 55-64 years 17 0.012 0.017 0.020 0.034 0.068 ≥65 years 18 0.013 0.018 0.022 0.036 0.072 aBased on water consumption rates estimated by EPA (2000a). EXPOSURES FROM FLUORINATED ANESTHETICS The sampled data in Table B-15 illustrate wide ranges of reported mean peak serum fluoride concentrations from the use of fluorinated anesthetics under various surgical conditions and for different age groups ranging from 22-day-old infants to people > 70 years old. These data are collected from studies conducted in many countries, including Australia, France, Finland, Germany, Ireland, Japan, the United Kingdom, and the United States. The

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-12 Estimated Intake of Fluoride from Community Water for 90th Percentile Consumersa     Fluoride Level   Water Intake, mL/day 0.7 mg/L 1 mg/L 1.2 mg/L 2 mg/L 4 mg/L Population Intake, mg/day All consumers 2,069 1.45 2.07 2.48 4.14 8.28 <0.5 year 943 0.66 0.94 1.13 1.89 3.77 0.5-0.9 year 950 0.67 0.95 1.14 1.90 3.80 1-3 years 719 0.50 0.72 0.86 1.44 2.88 4-6 years 940 0.66 0.94 1.13 1.88 3.76 7-10 years 995 0.70 1.00 1.19 1.99 3.98 11-14 years 1,415 0.99 1.42 1.70 2.83 5.66 15-19 years 1,669 1.17 1.67 2.00 3.34 6.68 20-24 years 2,175 1.52 2.18 2.61 4.35 8.70 25-54 years 2,326 1.63 2.33 2.79 4.65 9.30 55-64 years 2,297 1.61 2.30 2.76 4.59 9.19 ≥65 years 2,190 1.53 2.19 2.63 4.38 8.76   Water Intake, mL/kg/day Intake, mg per kg body weight/day All consumers 33 0.023 0.033 0.040 0.066 0.132 <0.5 year 169 0.118 0.169 0.203 0.338 0.676 0.5-0.9 year 116 0.081 0.116 0.139 0.232 0.464 1-3 years 53 0.037 0.053 0.064 0.106 0.212 4-6 years 45 0.032 0.045 0.054 0.090 0.180 7-10 years 33 0.023 0.033 0.040 0.066 0.132 11-14 years 27 0.019 0.027 0.032 0.054 0.108 15-19 years 26 0.018 0.026 0.031 0.052 0.104 20-24 years 31 0.022 0.031 0.037 0.062 0.124 25-54 years 32 0.022 0.032 0.038 0.064 0.128 55-64 years 32 0.022 0.032 0.038 0.064 0.128 ≥65 years 32 0.022 0.032 0.038 0.064 0.128 aBased on water consumption rates estimated by EPA (2000a). minimum alveolar concentration per hour (MAC-hr) ranged from short-term (e.g., for cesarean section as reported by Abboud et al. 1989) to prolonged (e.g., >10 hours as reported by Murray et al. 1992 and Obata et al. 2000) surgery and up to 7 days of continuous exposure for critically ill patients (e.g., as reported by Osborne et al. 1996). Test subjects included healthy males who underwent 3-9 hours of anesthesia (Munday et al. 1995), female smokers (Laisalmi et al. 2003), infants and children (age as indicated

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-13 Estimated Intake of Fluoride from Community Water for 95th Percentile Consumersa     Fluoride Level   Water Intake, mL/day 0.7 mg/L 1 mg/L 1.2 mg/L 2 mg/L 4 mg/L Population Intake, mg/day All consumers 2,600 1.82 2.60 3.12 5.20 10.40 <0.5 year 1,064 0.74 1.06 1.28 2.13 4.26 0.5-0.9 year 1,122 0.79 1.12 1.35 2.24 4.49 1-3 years 952 0.67 0.95 1.14 1.90 3.81 4-6 years 1,213 0.85 1.21 1.46 2.43 4.85 7-10 years 1,241 0.87 1.24 1.49 2.48 4.96 11-14 years 1,742 1.22 1.74 2.09 3.48 6.97 15-19 years 2,159 1.51 2.16 2.59 4.32 8.64 20-24 years 3,082 2.16 3.08 3.70 6.16 12.33 25-54 years 2,926 2.05 2.93 3.51 5.85 11.70 55-64 years 2,721 1.90 2.72 3.27 5.44 10.88 ≥65 years 2,604 1.82 2.60 3.12 5.21 10.42   Water Intake, mL/kg/day Intake, mg per kg body weight/day All consumers 44 0.031 0.044 0.053 0.088 0.176 <0.5 year 204 0.143 0.204 0.245 0.408 0.816 0.5-0.9 year 127 0.089 0.127 0.152 0.254 0.508 1-3 years 68 0.048 0.068 0.082 0.136 0.272 4-6 years 65 0.046 0.065 0.078 0.130 0.260 7-10 years 39 0.027 0.039 0.047 0.078 0.156 11-14 years 36 0.025 0.036 0.043 0.072 0.144 15-19 years 32 0.022 0.032 0.038 0.064 0.128 20-24 years 39 0.027 0.039 0.047 0.078 0.156 25-54 years 40 0.028 0.040 0.048 0.080 0.160 55-64 years 38 0.027 0.038 0.046 0.076 0.152 ≥65 years 37 0.026 0.037 0.044 0.074 0.148 aBased on water consumption rates estimated by EPA (2000a). in Table B-15), and patients with renal insufficiency (Conzen et al. 1995). In general, higher MAC-hr resulted in higher peak serum inorganic fluoride concentration. None of the studies presented in Table B-15 shows clear evidence of renal impairment as a result of the increased serum fluoride concentration, except transient reduction in renal function among the elderly (>70 years) reported by Hase et al. (2000). Higher peak serum concentration

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-14 Estimated Intake of Fluoride from Community Water for 99th Percentile Consumersa Population Water Intake, mL/day Fluoride Level.   0.7 mg/L 1 mg/L 1.2 mg/L 2 mg/L 4 mg/L     Intake, mg/day All consumers 4,273 2.99 4.27 5.13 8.55 17.09 <0.5 year 1,366 0.96 1.37 1.64 2.73 5.46 0.5-0.9 year 1,529 1.07 1.53 1.83 3.06 6.12 1-3 years 1,387 0.97 1.39 1.66 2.77 5.55 4-6 years 1,985 1.39 1.99 2.38 3.97 7.94 7-10 years 1,999 1.40 2.00 2.40 4.00 8.00 11-14 years 2,564 1.79 2.56 3.08 5.13 10.26 15-19 years 3,863 2.70 3.86 4.64 7.73 15.45 20-24 years 5,356 3.75 5.36 6.43 10.71 21.42 25-54 years 4,735 3.31 4.74 5.68 9.47 18.94 55-64 years 4,222 2.96 4.22 5.07 8.44 16.89 ≥65 years 3,668 2.57 3.67 4.40 7.34 14.67   Water Intake, mL/kg/day Intake, mg per kg body weight/day All consumers 79 0.055 0.079 0.095 0.158 0.316 <0.5 year 240 0.168 0.240 0.288 0.480 0.960 0.5-0.9 year 170 0.119 0.170 0.204 0.340 0.680 1-3 years 112 0.078 0.112 0.134 0.224 0.448 4-6 years 95 0.067 0.095 0.114 0.190 0.380 7-10 years 60 0.042 0.060 0.072 0.120 0.240 11-14 years 54 0.038 0.054 0.065 0.108 0.216 15-19 years 62 0.043 0.062 0.074 0.124 0.248 20-24 years 80 0.056 0.080 0.096 0.160 0.320 25-54 years 65 0.046 0.065 0.078 0.130 0.260 55-64 years 58 0.041 0.058 0.070 0.116 0.232 ≥65 years 53 0.037 0.053 0.064 0.106 0.212 aBased on water consumption rates estimated by EPA (2000a). was reported for smokers (Cousins et al. 1976; Laisalmi et al. 2003) and is associated with alcohol, obesity, and multiple drug use (Cousins et al. 1976). Because the reference point for the potential nephrotoxicity in these studies was the peak serum fluoride concentration, data are generally not available for an estimation of the total fluoride load or the area under the curve from the use of these anesthetics.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-15 Serum Inorganic Fluoride Concentration from Fluorinated Anesthetic Agents       Mean Serum Inorganic Fluoride, μM   Age (range) No. of Subjects MAC-houra Baseline Peak References Isoflurane           51 years 13 NA NA No change Hara et al. 1998 NA 90 NA NA 3 Groudine et al. 1999 >70 years 6 3.7 NA 4 Hase et al. 2000 55.5 years 26 NA about 2.5 5 Goldberg et al. 1996 57 years 24 1.1 3.8 5.4 Newman et al. 1994 28 years 11 9.2 <2 5.5 Higuchi et al. 1995 28 yearsb 20 0.06 5.6 5.6 Abboud et al. 1989 27.7 yearsb 20 0.14 5.9 5.6 Abboud et al. 1989 48.5 years 20 15.9 NA 7.4 Obata et al. 2000 53.7 years 7 4.8 NA 8 Matsumura et al. 1994 26-54 years 5 NAc 2.1-2.4 8.4-27.9 Osborne et al. 1996 20-75 years 9 19.2 3.5-3.8 43.2 Murray et al. 1992 Enflurane           22 days to 11 years 40 0.3-0.7 NA 2-8 Oikkonen and Meretoja 1989     0.7-1.5 NA 4-10 Oikkonen and Meretoja 1989     1.5-3.3 NA 6-10 Oikkonen and Meretoja 1989 22 day 1 0.6 NA 3 Oikkonen and Meretoja 1989 29 day 1 1.5 NA 7 Oikkonen and Meretoja 1989 3 months 1 1.6 NA 11 Oikkonen and Meretoja 1989 4 months 1 1.6 NA 11 Oikkonen and Meretoja 1989 9 months 1 2.0 NA 7 Oikkonen and Meretoja 1989 1-9 years 8 NA 1.7 10.5 Hinkle 1989 47-60 years 5 4-6.8 about 2-3 7 Sakai and Takaori 1978 63.9 years 20 1.07 NA 13.3 Conzen et al. 1995 48 years(27-58 years) 16 1 NA 13.8 Laisalmi et al. 2003

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards 44 years (35-39 years)d 17 1 NA 18.7 Laisalmi et al. 2003 59.3 years 40 2.8 1.2 16.75 Blanco et al. 1995 47.8 years 8 1.24 2-2.5 18 Cousins et al. 1987 40.2 years 10 2.7 1.8 22.2 Cousins et al. 1976 18-35 years 5 6   28.1 Munday et al. 1995 18-35 years 5   NA 27.5 Munday et al. 1995 Halothane           41.5 years 10 4.9 1.9 1.6 Cousins et al. 1976 6.2 years (1-12 years) 40 2.6 NA 1.8 Sarner et al. 1995 42-57 years 5 2.9-4.9 2-3 3 Sakai and Takaori 1978 50 years 8 2.5 2-2.5 4 Cousins et al. 1987 28.9 years 20 0.07 5.9 5.6 Abboud et al. 1989 9.2 years (5-12 years) 25 2.2 NA 6 Taivainen et al. 1994 20-75 years 10 19.5 3.8 12.6 Murray et al. 1992 Sevoflurane           12 months (7.7-25 months) 41 4.7 NA 13.8 Lejus et al. 2002 6.2 years (1-12 years) 40 2.6 NA 14.7 Sarner et al. 1995 >70 years 7 5.1 NA 18 Hase et al. 2000 8.8 years 25 2.2 NA 21 Taivainen et al. 1994 50 years 25 0.8 3.8 23 Newman et al. 1994 67.4 years 21 1.01 NA 25 Conzen et al. 1995 60.5 years 40 2.9 1.2 27.7 Blanco et al. 1995 52.7 years 24 NA about 2.5 28 Goldberg et al. 1996 18-35 years 5 3 NA 30.5 Munday et al. 1995   5 6   31-34     5 9   36.6   29 years 15 9.9 <2 36.8 Higuchi et al. 1995 53 years 13 3.7 NA about 31 Hara at al. 1998 NA 98 2.9 NA 40 Groudine et al. 1999

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards       Mean Serum Inorganic Fluoride, μM   Age (range) No. of Subjects MAC-houra Baseline Peak References 26.6 years (19-49 years) 11 10.6 NA 41.9 Higuchi et al. 1994 56.8 years 10 18.0 high flow NA 47.1 Obata et al. 2000 62.0 years 10 16.7 low flow NA 53.5 Obata et al. 2000 54.9 years 8 6.1 NA 54 Matsumura et al. 1994 24 years 8 14.0 <2 57.5 Higuchi et al. 1995 aMAC is the minimum alveolar concentration, or the mean end-tidal anesthetic concentration. When MAC-hr is not reported, it is estimated as MAC-hr = (mean percent concentration) x (anesthesia time). bCesarean section patients with induction to delivery time of 7.4-8.4 minutes. cCritically ill patients under anesthesia for 5-7 days at 0.6-1.2% isoflurane. dSmoking > 10 cigarettes a day. ABBREVIATION: NA, not applicable.

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-16 Summary of Estimated Safe and Adequate Daily Dietary Intakesa of Fluoride Age, years Weight, kgb Range, mg/day Range, mg/kg/dayc 0-0.5 6 0.1 0.5 0.017 0.083 0.5-1 9 0.2 1.0 0.022 0.11 1-3 13 0.5 1.5 0.038 0.12 4-6 20 1.0 2.5 0.050 0.13 7-10 28 1.5 2.5 0.054 0.089 Males 11-14 45 1.5 2.5 0.033 0.056 15-18 66 1.5 2.5d 0.023 0.038 19-24 72 1.5 4.0e 0.021 0.056 25-50 79 1.5 4.0 0.019 0.051 51+ 77 1.5 4.0 0.019 0.052 Females 11-14 46 1.5 2.5 0.033 0.054 15-18 55 1.5 2.5d 0.027 0.045 19-24 58 1.5 4.0e 0.026 0.069 25-50 63 1.5 4.0 0.024 0.063 51+ 65 1.5 4.0 0.023 0.062 aThe term “safe and adequate daily dietary intake” was used by the NRC (1989b) “when data were sufficient to estimate a range of requirements, but insufficient for developing [a Recommended Dietary Allowance].” This category was to be accompanied by “the caution that upper levels in the safe and adequate range should not be habitually exceeded because the toxic level for many trace elements may be only several times usual intakes.” Use of this term should not be taken to imply that the present committee considers these intakes to be safe or adequate. bMedian for age group. cCalculated from range (mg/day) and weight (kg) given for age groups. dUpper limit for children and adolescents (upper age not specified). eUpper limit for adults. SOURCE: NRC 1989b. REFERENCE INTAKES OF FLUORIDE Table B-16 provides the median weight and range of fluoride intake (mg/day; safe and adequate daily dietary intake5), by age group, from the National Research Council (NRC 1989b). Table B-17 provides the reference 5 The term “safe and adequate daily dietary intake” was used by the NRC (1989b) “when data were sufficient to estimate a range of requirements, but insufficient for developing [a Recommended Dietary Allowance].” This category was to be accompanied by “the caution that upper levels in the safe and adequate range should not be habitually exceeded because the toxic level for many trace elements may be only several times usual intakes.” Use of this

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Fluoride in Drinking Water: A Scientific Review of EPA’S Standards TABLE B-17 Summary of Dietary Reference Intakes of Fluoride   Reference Weight, kg Adequate Intake Tolerable Upper Intake Age, years mg/d mg/kg/daya mg/d mg/kg/daya 0-0.5 7 0.01 0.0014 0.7 0.10 0.5-1 9 0.5 0.056 0.9 0.10 1-3 13 0.7 0.054 1.3 0.10 4-8 22 1 0.045 2.2 0.10 9-13 40 2 0.050 10 0.25 Boys 14-18 64 3 0.047 10 0.16 Girls 14-18 57 3 0.053 10 0.18 Males 19+ 76 4 0.053 10 0.13 Females 19+ 61 3 0.049 10 0.16 aCalculated from intake (mg/day) and weight (kg) given for age groups by IOM (1997) and ADA (2005). SOURCES: IOM 1997; ADA 2005. weight and range of fluoride intake (mg/day; dietary reference intake), by age group, from the Institute of Medicine (IOM 1997) and the American Dental Association (ADA 2005). In both tables, the intakes in terms of mg/ kg/day were calculated from the cited information as indicated. term should not be taken to imply that the present committee considers these intakes to be safe or adequate.