EWG Letter to EPA

January 4, 2007

Mr. Jim Jones, Director
Office of Pesticide Programs
Environmental Protection Agency
Mail Code 7510P
1200 Pennsylvania Avenue, NW
Washington, DC 20460-0001

Dear Mr. Jones,

Four years ago the Environmental Protection Agency (EPA) banned nearly all uses of the widely used arsenic and chromium-based wood preservative chromated copper arsenate (CCA). The ban was driven by a concern for public health — specifically, the cancer risks that arsenic-treated lumber presented to the nation's children. Scientists at Environmental Working Group (EWG), a watchdog organization based in Washington, DC, brought these risks to EPA's attention, and we commend the agency for taking action to get this dangerous product off the market.

Now it appears that you, as director of the pesticide program at the EPA, are about to recommend a giant step backwards in public health protections, and grant an unrestricted registration to the cancer-causing hexavalent chromium-based wood preservative acid copper chromate (ACC). We strongly urge you not to register ACC for the proposed uses until the cancer risks to children are fully understood.

Twenty years ago the pesticide program made the wrong decision with arsenic treated lumber, allowing the compound to stay on the market, exposing an entire generation of children to unsafe levels of cancer causing arsenic. Today, millions of schools, parks, and backyards across America have decks, picnic tables, and play structures made with this carcinogen-laden wood.

If you grant these new registrations, you will again expose millions of children, homeowners, and workers to the known, highly potent carcinogen and allergen hexavalent chromium, and you will do this without even assessing the cancer risks that this chromium-based pesticide will pose to children.

You have justified this failure by citing uncertainties about the cancer risk of hexavalent chromium when it is ingested, as millions of infants and young children will certainly do if you grant full registration. Yet the National Toxicology Program (NTP) is currently studying hexavalent chromium carcinogenicity by ingestion in rodents, with results expected later this year. Why rush to register this pesticide now when the overwhelming weight of the evidence indicates that hexavalent chromium will in fact cause cancer when it is ingested? Hexavalent chromium is a known human carcinogen via inhalation, and according to our review of the National Toxicology Program's 11th report on carcinogens, every single known human carcinogen tested by more than one route of exposure (27 out of 27) is carcinogenic by more than one route. In addition to inhalation, hexavalent chromium produces malignant tumors via subcutaneous injection, and several published studies indicate that chromium is carcinogenic by ingestion.

Given this evidence and the real chance that the NTP study will find hexavalent chromium to cause cancer by ingestion, it would be completely irresponsible to register ACC at this time.

Before you decide the fate of ACC's registration on January 19th, please tell us, so we can tell homeowners, parents and contractors:

• How much hexavalent chromium do you think is acceptable for a one-year- old infant to ingest, and where can a parent find your assessment of hexavalent chromium safety for infants and children?
• What is the risk that a person will develop cancer from early childhood exposure to hexavalent chromium on treated wood? If you do not know the answer to this question, the public deserves to know why you rushed to register a known carcinogen for uses the will directly expose children, when a critical study that will substantially clarify the risks is expected within a year.
• How long, under different conditions, does it take for the potent carcinogen hexavalent chromium to convert into the less toxic trivalent chromium in a piece of ACC-treated wood? This question is not only important for parents whose children play on treated wood structures, but also for homeowners and contractors who will be sawing, sanding, and working with ACC-treated lumber. Hexavalent chromium is extremely toxic to humans when inhaled. Carpentry work using new ACC-treated wood is of particular public health concern because of sawdust inhalation.
• How did you determine that there is no difference in skin sensitivity to hexavalent chromium among all 300 million people in the United States? This is an extraordinary, if not unprecedented finding, and deserves an explanation. EPA has adopted an uncertainty factor of 1 for hexavalent chromium, yet we have never heard of any substance where there was no variability in sensitivity to exposure over such large exposed population. EPA has no direct measurement of skin sensitization in children, but instead has assumed that the skin of a baby is no more sensitive to hexavalent chromium than the skin of an adult, male, construction worker.
• How will Americans know it is dangerous to burn scraps of ACC-treated wood? A substantial portion of trivalent chromium converts back into the hexavalent chromium when ACC wood is burned, which means that the treated wood does not stop being dangerous once it ages. Even if every single piece of ACC wood were labeled with a warning before it was delivered to stores, this label would inevitably be removed leaving the public with no way to know that a benign-looking piece of scrap lumber is dangerous when burned.
• What level of contact have you had with the chromium industry and/or wood preservers lobby? How many times have you communicated with the Forest Research Product Laboratory (FRPL) over the phone, in person, or via e-mail or paper regarding the registration of ACC? How many times have you had similar communications with other groups or individuals representing the chromium and/or wood treatment industry? Have you had any contact with former Senator Bob Dole? These are important questions for the public to have answers to since these groups stand to reap millions of dollars in profits if ACC is approved for residential use, while the public only stands to gain another massive toxic waste problem.

We appreciate your timely response to these questions.

Sincerely,

[signed]

Richard Wiles
Executive Director