SAB PUSHES FOR EPA TO USE CONTROVERSIAL 'NONLINEAR' RISK METHOD

摘要

EPA's Science Advisory Board (SAB) is poised to recommend the agency develop a complex "nonlinear" model to examine the cancer risks posed by ethylene oxide (EtO) at low doses, adding to growing pressure from key administration officials and industry for the agency to use the approach when assessing chemicals' health risks. The recommendation is also a victory for industry officials because it could delay the agency's first use of strict safety factors aimed at protecting children from harmful exposures, which the agency's 2005 cancer guidelines endorsed. Historically EPA has used a linear risk model to extrapolate the cancer risks of substances at low doses — effectively drawing a straight line from data on higher doses through zero to estimate the risks posed by a substance at lower doses. The linear approach assumes carcinogens pose risks at any level of exposure unless clear scientific data indicates otherwise.