Daily News Archive
Risk from CCA-Treated Wood Found, EPA Plods Along
EPA generally accepts one excess cancer case per million people exposed as its acceptable threshold, whereas children exposed to CCA-treated wood suffer as much as five cancer cases per 10,000 exposed, according to the new analysis. These risk numbers themselves are viewed by many environmentalists and public health advocates as filled with uncertainties and an underestimation of real world risk, given other exposures that children experience to the components of CCA, whether it is environmental contamination of air, water, soil and food from other uses of the chemicals, beyond playsets and decks.
The "Draft Final Report," A Probabilistic Risk Assessment for Children Who Contact CCA-Treated Playsets and Decks, dated November 10, 2003, will be the subject of a Scientific Advisory Panel (SAP) meeting on December 3-5, 2003 in Crystal City, Virginia at the Sheraton Hotel. The meeting will focus on the probabilistic exposure and risk assessment for children who contact CCA-treated wood on playsets and decks and CCA-containing soil around these structures.
The agency's new analysis is called a probabilistic risk assessment because it is intended to predict variability of absorbed doses for, in this case, children. The model is supposed to fine tune exposure estimates and utilize a sensitivity analysis. However, the document notes: "The current policy, Conditions of Acceptance and associated principles, are not intended to apply to dose-response evaluations for human health risk assessments until this application has been studied further (Agency Policy Document, 5/15/1997). Currently, [the Office of Pesticide Programs] OPP does not have the Guidance to perform the probabilistic analysis of toxicity endpoints." There is still great scientific debate on the validity of setting a predicted threshold dose (the point at which the disease endpoint occurs) for acceptable exposure to cancer causing agents like arsenic and chromiumVI, two components of CCA, because of the long-term nature of the disease and the reliance on best-guess analyses that extrapolate from high dose experimentation with laboratory animals. As a result, many scientists, who say that determining a threshold exposure is impossible, argue that that there is no acceptable exposure for carcinogens, especially for children and other sensitive population groups. This and other deficiencies associated with risk assessment's uncertainties support advocates' insistence on the adoption of the precautionary principle, which supports stopping any continued exposure to the extent possible.
These are extraordinary risks when compared to what EPA says is the "acceptable" one in a million [10 x 10(-6)] risk that the agency uses. The risk factors are between 2,000 and 5,000 times higher than those normally viewed by EPA as acceptable for chronic effects like cancer. The study looks at various mitigation measures as a means of reducing risk (which would have relevancy to existing structures that are in place).
This information is incredibly important, because as EPA notes itself in this document (p. 2-5 first paragraph) "Consumers may continue to buy and use the treated CCA wood for as long as it is available." While the major producers of playsets have said that they will no longer use CCA wood, there are smaller companies and lumber for decks, porches, handrails, etc. are still being put on and around people's homes daily. The way EPA "phases" out chemical exposures it knows to be harmful is viewed by Beyond Pesticides as unconscionable and illegal. Beyond Pesticides, the Communication Workers of America (AFL-CIO), the Center for Environmental Health (Oakland, CA) and a victim family in Florida, filed a lawsuit against EPA to end the continued use of the heavy duty wood preservatives, including CCA, pentachlorophenol and creosote. The agency has made a policy decision in negotiating certain CCA uses off the market, that it will allow phase-outs without any mandatory warning or notice to the consumer. Meanwhile, a Michigan TV station came across a leaflet in Home Depot stores that said outright that CCA wood is not a problem (see Streaming Video: The Arsenic Threat: Pressure Treated Wood, CBS Affiliate WWMT-3, Michigan).
According to Beyond
Pesticides, the continuing and critically important public health issues
Policy issues, according to Beyond Pesticides, include the regulation of wood preservatives as a case study of the failure EPA to adequately, and in a timely manner, protect public health and the environment. The negotiating posture of EPA on these chemicals, according to the group, has resulted in a lack of warning to the public about known hazards for over two decades. When EPA agreed in the 1980's, after over a decade of review, to allow CCA wood to continue to be sold at the retail level, it had originally proposed a mandatory consumer information program and the tagging of wood. It negotiated back to a voluntary program that resulted in virtually no compliance with the voluntary warning guidelines, according to state officials responsible for enforcing pesticide law. Even under a newly negotiated warning agreement just over a year ago, investigations by the media point to inadequate notice and misinformation in the marketplace.