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NTP — Atrazine: Request for Reconsideration (RFR)

Date: June 24, 2005

Associate Director for Communications 
Office of the Director 
National Institutes of Health

(By Hand Delivery)

Dear Sir or Madam:

By this document, we appeal the denial of our request for correction (“RFC”) under the Information Quality Act (“IQA”).1

We ask that the Denial be overturned on appeal, and that our RFC be granted, for the reasons stated in our RFC. Our appeal will not reiterate the background and arguments made in our RFC. Those arguments are instead incorporated herein by reference.2  We do, however, emphasize here that the Denial fails to address the primary argument made in our RFC.

Our RFC correctly argued that the National Toxicology Program (“NTP”) violated the IQA Objectivity requirement by disseminating an incomplete statement of IARC’s findings about atrazine and cancer. This NTP dissemination is misleading, inaccurate and biased because it omits other IARC findings contained in the same IARC Monograph. These other IARC findings are crucial in this context because their omission by NTP changes the meaning of what IARC actually found.3This change misleads and misinforms the public.

The NTP’s violation of the IQA Objectivity Standard is obvious in light of the Office of Management & Budget’s (“OMB”) interpretation of this Standard, as well as the Department of Health and Human Services’s (“HHS”). OMB’s and HHS’s interpretations are binding on NTP:

“‘Objectivity’ includes whether disseminated information is being presented in an accurate, clear, complete, and unbiased manner. This involves whether the information is presented within a proper context. Sometimes, in disseminating certain types of information to the public, other information must also be disseminated in order to ensure an accurate, clear, complete, and unbiased presentation.”4

This is one of those times.

The specifics of this issue are addressed in detail in our RFC.5 We will not repeat that discussion but do emphasize the following facts.

The NTP states in the Federal Register, on the NTP website, and elsewhere that there is an “IARC finding of sufficient evidence of carcinogenicity [of atrazine] in animals (Vol. 73, 1999).”6

This NTP characterization of IARC’s findings is the only basis for NTP’s proposed review of atrazine as a human carcinogen in the 12th Report on Carcinogens (“RoC”). In this context, the average reader would conclude that IARC found atrazine could cause human cancer because it caused lab-rat cancer. What else would the uninformed, or in this case misinformed, conclude from the phrase “sufficient evidence of carcinogenicity in animals” when that phrase is used as the sole basis for RoC review as a human carcinogen ?

In fact, IARC did not find that there was “sufficient evidence” that atrazine causes human cancer. 7

In fact, IARC found that the rat tests in question were irrelevant to human cancer risk because the rat mechanism of action does not exist in humans.8

In fact, IARC found that “[t]here is inadequate evidence in humans for the carcinogenicity of atrazine.”9

In fact, IARC’s “Overall evaluation” of atrazine is: “Atrazine is not classifiable as to its carcinogenicity to humans.10 The emphasis is in the original IARC Monograph from which this quote is taken.

For these reasons, the NTP statement about IARC’s atrazine findings violates the IQA’s requirements that information be disseminated in an accurate, clear, complete and unbiased manner.11

For these reasons, the NTP statement about IARC’s atrazine findings violates the IQA’s requirement that disseminated information be accurate, complete and unbiased. 12 Internal NTP documents obtained through a Freedom of Information Act(“FOIA”) request demonstrate that NTP thought the IARC information NTP deleted from its Federal Register notice was important.

One of these FOIA documents is entitled



This FOIA document is dated before NTP published its misleading Federal Register notice that NTP was considering atrazine for review in the 12th RoC. For atrazine, under a column titled “NOMINATION RATIONALE,”this FOIA document states:“IARC Group 3 (1999) Sufficient evidence in animals (mammary tumors in female Sprague-Dawley rats but not Fischer 344 rats). IARC stated that the mechanism for mammary tumor formation in rats was hormonally mediated and was not relevant to humans.”

The irrelevance of these rat tumors to humans was stated clearly for purposes of internal NTP consideration of the rationale for possible RoC review. Why was it not included in NTP’s Federal Register notice to the public ?

Another FOIA document is entitled:



Summary of Nomination For Review: 
NTP 12th Report on Carcinogens

September 2003

Submitted by 
Report on Carcinogens Group 

The Introduction to this document states:

“IARC evaluated atrazine in 199 and classified it as not classifiable as to its carcinogenicity to humans (Group 3). The working group stated that while there was sufficient evidence for the carcinogenicity of atrazine in animals the mechanism of carcinogenicity was hormonally mediated and was not relevant to humans (IARC) 1999)”

The irrelevance of these rat tumors to humans was considered important and emphasized by NTP’s own group reviewing the nomination. Why was it not important enough to include in NTP’s Federal Register notice to the public?

The Denial suggests that we are using to the IQA to challenge NTP’s “policy decision” to consider atrazine for review in the 12th RoC. We are not. We are instead using the IQA to correct NTP’s incomplete, misleading, inaccurate and biased public dissemination of IARC’s findings about atrazine and cancer.

We do, however, ask why NTP even considered using IARC’s atrazine findings as the basis for possible atrazine review in the 12th RoC.

NTP stated publicly that it accepted atrazine for review in the 12th RoC for only one reason: “IARC finding of sufficient evidence of carcinogenicity in animals.”15

NTP’s stated basis for accepting atrazine for review would not satisfy the RoC cancer classification criteria even if it were accurate.16 The animal tests referenced in the IARC findings involved only one type of tumor at one site in one sex of a single highly vulnerable rat species. The animal tests do not show or rely on multiple routes of exposure. They do not show  an unusual degree with regard to incidence, site or type of tumor, or age of onset.17  Consequently, the IARC animal test findings could not support atrazine RoC review. 18

Nor is there any other basis for concluding that atrazine is a human carcinogen.

After years of review, EPA recently concluded that atrazine is “not likely to be carcinogenic to humans.” 19 EPA reached this conclusion several years after the IARC Monograph on atrazine, and after painstaking review of all the latest evidence.

Soon after EPA’s conclusion, researchers for the EPA, National Cancer Institute, and National Institute of Environmental Health and Safety jointly “found no associations between cancer incidence and atazine exposure, whether atrazine was analyzed as a cumulative measure (lifetime days of exposure) or as an intensity-weighted cumulative measure (intensity-weighted lifetime days of exposure).” 20 This conclusion is based on a massive epidemiological study of commercial and private atrazine applicators.21

EPA has asked in writing that NTP not review atrazine as a human carcinogen because such review would be duplicative, unnecessary, and a waste of time, effort, and tax dollars.

The Department of Agriculture concurs in writing with EPA’s request.22

The overwhelming weight of scientific evidence is that atrazine is neither a known nor a reasonably anticipated human carcinogen, and these are the only two RoC cancer classifications. 23

EPA’s atrazine Federal Register notice and the FOIA documents quoted above contain extensive discussions of the IARC Monograph and some other reports/studies on atrazine. Yet they do not mention EPA’s study and conclusion that atrazine is not likely to be carcinogenic in humans. EPA issued a report with this conclusion in April 2002.24 EPA reiterated this conclusion after further study in a report issued in January 2003.25  These EPA reports pre-date the FOIA documents and NTP’s Federal Register notice; yet they are not mentioned in them.

While we are not challenging NTP’s “policy decision” under the IQA, we do state that any NTP policy decision to review atrazine for the RoC at this time would arbitrary, capricious, irrational, and without any scientific basis.

Relief Requested

The Denial should be overturned on appeal. We should be granted the relief requested in our RFC under the subtitle “Correction Requested.”26


Please contact Jim Tozzi, 11 DuPont Circle, Suite 700, Washington, D.C. 20036, 202/265-2383, regarding our Appeal and our RFC.


Jim J. Tozzi 
CRE Board of Advisors

Jere White 
Kansas Corn Growers Association 
PO Box 446 
109 West 4th 
Garnett, KS 66032

Gary Marshall 
Missouri Corn Growers Association 
3118 Emerald Lane 
Jefferson City, MO. 65109

Stephanie Whalen 
Hawaii Agriculture Research Center 
Aiea Heights Drive, Suite 300 
Aiea, Hawaii 96701-3911

Joel Nelsen 
California Citrus Mutual 
512 North Kaweah Avenue 
Exeter, California 93221

David Schwartz, Director, National Toxicology Program 
Jon Scholl, Counsellor to the Administrator on Agricultural Policy, EPA 
Charles Havekost, Chief Information Officer, HHS 
Alan S. Graeff, Chief Information Officer, NIH 
Dona R. Lenkin, Deputy Chief Information Officer, NIH 
Allen L. Jennings, Office of Pest Management, USDA


1The letter denying our RFC is available online at NTP — Atrazine: HHS Response to RFC, May 25, 2005. This letter will hereinafter be referred to as “Denial.” We received the Denial on May 27, 2005. 

2Our RFC is available online at Request for Correction(RFC) 
3 This argument is made in our RFC at pages 2 and 4-5. By IARC, we mean International Agency for Research on Cancer. 
4OMB Government-Wide IQA Guidelines, Section V.3.a, 67 FR 8452, 8459 (Feb. 22, 2002) (emphasis added); HHS IQA Guidelines, Section I.D.2.c (emphasis added). The HHS IQA Guidelines are available online at
5See Footnote 3, supra. 
669 FR 28940, 28940-41 (May 19, 2004) (footnote to IARC citation omitted). The same information about the IARC atrazine finding is disseminated at 69 FR 62276 (Oct. 25, 2004); and on the NTP website at…
7IARC Monographs on the Evaluation of Carcinogenic risks to Humans, “Some Chemicals that Cause Tumors of the Kidney or Urinary Bladder in Rodents and Some Other Substances,” Vol. 73, pages 94-99 (copy included in Appendix "A" to our RFC). 
9Id., page 99. 
10Id., page 99. 
11E.g., OMB IQA Guidelines, Section V.3.a, 67 FR at 8459; HHS IQA Guidelines, Section I.D.2.c (emphasis added). 
12E.g., OMB IQA Guidelines, section V.3.b, 67 FR at 8459;  HHS IQA Guidelines, Section I.D.2.c. 
13This FOIA document is attached as Appendix 1 (emphasis added). 
14This FOIA document is attached as Appendix 2 (emphasis added). 
15Footnote 6,supra
16The RoC criteria are available online at… 
17IARC Monograph, Footnote 7 supra,pages 97-98. 
18See RoC criteria for classifying human carcinogens solely on the basis of animal tests at… 
19See Appendix "B" to our RFC on atrazine at p. 2. 
20Rusiecki,J., et al.Cancer Incidence Among Pesticide Applicators Exposed to Atrazine in the Agricultural Health Study, Journal of the National Cancer Institute, Vol. 96, No. 18, September 15, 2004, at p. 1380. 
21Id. at p. 1376. 
22The EPA comments are available online at The Department of Agriculture comments are available online under “Allen L. Jennings, Office of Pest Management, USDA,” at… 
23Footnote 16, supra. 
26RFC at page 6.