Dismissed EPA toxicologist denies bias

A toxicologist, whose comments were removed from a US government chemical safety report after industry intervention, has defended herself against charges of bias during a Congressional hearing. 

Deborah Rice, now with the Maine Center for Disease Control and Prevention, chaired an Environmental Protection Agency (EPA) panel that examined polybrominated diphenyl ethers (PBDEs) - a flame-retardant chemical added to many products, including electronic devices and foam mattresses. 

But EPA deleted Rice’s name and comments from the panel’s final report after the American Chemistry Council (ACC) contacted the agency in May 2007, alleging Rice should not be allowed to serve on the committee because she had testified before the Maine state legislature supporting a bill to phase-out one specific PBDE known as deca-BDE. 

Rice, however, denies bias. ’I believe that having an informed scientific opinion constitutes neither bias nor conflict of interest,’ she told the House of Representatives’ Energy and Commerce Committee on 18 September. ’Indeed, if this is the definition of bias, then only individuals who are uninformed on a particular chemical would be considered suitable to serve as peer reviewers.’ 

Her statements to the Maine legislature focused on whether safer chemicals are available as substitutes for deca-BDE, said Rice. But her work on the EPA panel involved determining a safe level of intake for that chemical and several other PBDEs. ’My view that safer chemicals were available did not reflect on my ability to follow the EPA protocol for derivation of a reference dose,’ she added. 

Also giving evidence, George Gray, EPA’s assistant administrator for research and development, told the committee that Rice had failed to mention her earlier public testimony in a disclosure form she submitted before joining the EPA panel. ’Because the disclosure rules had not been followed, it was inappropriate for her comments to be part of the record,’ Gray said. 

Rice, however, said she had failed to declare the Maine testimony because she hadn’t linked it to her work for the EPA. 

Process failures 

The ACC maintains that the EPA failed to vet the panel adequately. ’At that late date, there really was no satisfactory way to undo the damage caused by the process failures; as a result, we were reduced to asking EPA to base its final toxicological review on data, opinions and conclusions other than the chairperson’s,’ said Sharon Kneiss, vice-president of the ACC’s products divisions. 

In the end, EPA set a safe daily dosage for deca-BDE that is ’three orders of magnitude lower than the best available science supports,’ Kneiss added - setting an oral reference dose (rFD) of 7 microgrammes per kg in June for deca-BDE, compared to the US National Research Council’s estimate of 4mg per kg. 

In the US, two states - Maine and Washington - have banned the use of deca-BDE in certain applications, and eight others are working to phase out the chemical. The chemical is also banned from electrical equipment in Europe. 

Animal studies suggest that deca and other PDBEs can disrupt hormones and alter brain activity, though human data is inconclusive. 

Rebecca Trager, US correspondent for Research Day USA Interesting? 

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