Richard Denison, Ph.D., is a Senior Scientist.
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Yesterday, the chair of a “Health Effects Expert Panel” convened by the West Virginia Testing Assessment Project (WV TAP) held a press conference to present the panel’s preliminary findings from its review of the “safe” level set by the Centers for Disease Control (CDC) for MCHM and other chemicals that spilled into the Elk River in early January and contaminated the drinking water of 300,000 West Virginia residents.
A final report from the panel apparently won’t be released until May, but a press release issued yesterday sounds far from preliminary in saying the panel supports CDC’s methods, assumptions, toxicity data and “safety factors.” While providing no details, the release indicates the panel is using the same flawed and incomplete summary of a toxicity study used by CDC in its rush to set a safe level for MCHM. And it parrots CDC’s erroneous use of the term “safety factors,” which is at odds with the National Academy of Sciences’ strong recommendation that such term should be avoided as it is highly misleading.
In addition to choosing to rely on the same summary CDC used of a 1990 study conducted by MCHM’s manufacturer, Eastman Chemical, the panel accepted at face value Eastman’s interpretation that the study identified a no-effect level. That conclusion has been questioned and cannot be independently assessed because Eastman has not provided the actual quantitative data from the study. Moreover, the study used a protocol dating from 1981 that has been extensively revised at least twice since then. These are among the many problems identified with this study.
It appears the panel’s main departure from CDC was to assume the most highly exposed population would have been formula-fed infants instead of older children. The panel’s “safe” level is 120 parts per billion (ppb), a value about 8-fold lower than CDC’s level of 1 part per million (ppm). That seems an improvement over the CDC’s methodology.
The panel’s conflict of interest
However, the process by which the panel itself was formed and the clear conflict of interest (COI) involved – a conflict that only came to light in response to a reporter’s questions at yesterday’s press conference – are deeply concerning. Read More