EPA criticised for hexavalent chromium move

12 October 2010


The US Environmental Protection Agency (EPA) has come under fire for moving hastily to potentially adopt stricter standards for hexavalent chromium (Cr(VI)) - a group of man-made compounds used in the production of stainless steel, chromate chemicals and pigments.

The EPA sought an immediate 60-day public comment period on its draft toxicological review of the safety of Cr(VI) on 30 September, a move the American Chemistry Council (ACC) calls 'premature'. The ACC supports a comprehensive risk assessment for Cr(VI), but says the agency issued its draft assessment before the results of a crucial upcoming study could be published.

Specifically, the EPA is conducting peer review of the scientific evidence supporting the human health hazard and dose-response assessment of Cr(VI). It will appear on the agency's Integrated Risk Information System (Iris) database - a programme that evaluates quantitative and qualitative risk information on human health effects that may result from exposure to environmental contaminants.

Meanwhile, the ACC has commissioned an independent science advisory board to examine health effects and fill in data gaps involving Cr(VI) modes of action. 'These new data, to be released by early 2011, could provide a more robust scientific basis to the cancer-risk assessment,' states Ann Mason, ACC's senior director. She says it's unclear why the EPA is acting now, rather than waiting to review these studies, some of which have already been released for peer review.

These key data under development will likely result in a 'more robust' cancer risk assessment for Cr(VI), ACC says. The lobby group expresses disappointment that the EPA has indicated it will rely on 2008 data from the federal National Toxicology Program, which it considers to be limited.

But ACC will likely have difficulty pushing its agenda on Cr(VI), given the political pressure facing the EPA. The substance - which the EPA and others recognise to be carcinogenic - is at the centre of a public firestorm.

In 2003, military contractor Kellogg, Brown and Root (KBR) allegedly exposed Oregon National Guardsmen to Cr(VI) in one of its facilities in Iraq. As a result, 26 Oregon veterans filed a lawsuit against the company in May. In response, several

Oregon lawmakers have introduced bipartisan legislation to increase accountability for military contracting by requiring disclosure of the presence of unusually hazardous or nuclear risks. KBR has dismissed the allegations against it as 'unproven, incorrect and baseless.'

Rebecca Trager, US correspondent for Research Europe

RSC