The Honorable Carol M. Browner
Administrator
U.S. Environmental Protection Agency
401 M Street, SW
Washington, DC 20460

Dear Administrator Browner:

The Committee on Science has received a number of letters recently regarding the potential health risk from fluoride in drinking water at the current maximum contaminant level (MCL). According to the enclosed Salon article and other information I have received, the current MCL may harm human health, particularly in certain sensitive subpopulations such as the young, the elderly, diabetics and athletes. In addition, the article states the Clinton Administration’s goal to increase the percentage of the population receiving fluoridated water from 62% to 75% by next year.

I would like to request your agency’s response to some questions I have regarding the fluoride:

1. I understand that EPA does not endorse water fluoridation. Has the agency taken any steps to have EPA removed from the list of endorsers of water fluoridation published by the American Dental Association? If you have, have they complied?

2. What chronic toxicity test data are there on sodium fluorosilicate? On hydrofluorsilicic acid?

3. What steps have you taken to address questions related to the EPA’s Maximum Contaminant Level Goal (MCL[G]) for fluoride in drinking water? If you have not taken steps to address these questions, why not? If not, when will you take such steps? When do you estimate that the work involved in addressing these questions will be complete?

4. Do you interpret Section 101(b)(4) of the Safe Drinking Water Act of 1996 as requiring EPA to set its MCL(G)s at a level that protects all persons, including sensitive subpopulations, such as infants, children, people who drink 4 or more liters of water per day, people with allergies or hypersensitivity to fluoride, and people with renal disease?

5. Is the Agency satisfied with fluoride doses delivered to the public via drinking water under and MCL(G) of 4 milligrams/liter (mg/l) when added to the fluoride intake from dental products, pesticide residues, food and beverages will not cause an adverse health effect?

6. What is the margin of safety for infants who consume drinking water containing 4 mg/l of fluoride?

7. What is the margin of safety for persons receiving kidney dialysis treatment, diabetics or those who have a hypersensitivity or allergy to fluoride who consume drinking water containing 4 mg/l of fluoride?

8. Does the incidence of dental fluorosis among at least 22% of American children indicate that, at least among these children, an overdosing as occurring?

9. What steps has the agency taken to address the hazards identified with fluoride exposure in the following publications that appeared since the EPA reaffirmed its drinking water standards for fluoride? These publications include:
   1. Neurotoxicity of sodium fluoride in rats. Mullenix, P.J., Denbesten, P.K., Schunior, a., and Kernan, W.J. Neurotoxicology and Teratology. 17 169-177 (1995)
   2. Influence of chronic fluorosis on membrane lipids in rat brain. Z.Z. Guan, Y.N. Wang, K.Q. Xiao, D.Y. Dai, Y.H. Chen, J.L. Liu, P. Sindclar and G. Dallner. Neurotoxicology and Teratology 20 537-542 (1998)
   3. Chronic administration of aluminum-fluoride or sodium fluoride to rats in drinking water: alterations in neuronal and cerebrovascular integrity. Varner, J.A., Jensen, K.F., Horvath, W., and Isaacson, R.L. Brain Research 784 284-298 (1998).
   4. Effect of high fluoride water supply on children’s intelligence. Zhao, L.B., Liang, G.H., Wu, X.R. Fluoride 29 190-192 (1996).
   5. Effect of fluoride exposure on intelligence in children. Li, X.S., Zhi, J.L., and Gao, R.O., Fluoride 28 (1995).
   6. Effect of fluoride on the physiology of the pineal gland. Luke, J.A. Caries Research 28 204 (1994).

Please provide the committee with copies of any EPA publications, studies, reports or memos relating to the fluoride MCL.

I respectfully request your response to our concerns. Thank you for your attention to this matter.

Sincerely,

KEN CALVERT
Chairman
Subcommittee on Energy and Environment

enc.
KC/tjv

• Congressman Sensenbrenner's Response to Dr. Thiessen (5/18/1999)
• Kathleen M. Thiessen, Ph.D. letter to Lee County (Florida) School Board (12/7/1998)
• Dr. Thiessen's letter to Congressman Sensenbrenner (3/30/1999)

Last modified: 10 July 1999

http://www.actionpa.org/fluoride/Calvert-to-Browner.html