RE: FGR-13

["Otto G. Raabe" <ograabe@ucdavis.edu>]

May 13, 1998
Davis, CA

EPA's desire to use risk-based regulations would be a great approach if it
were possible to accurately estimate the risk at low doses for radiation or
chemicals. However, the linear models used by EPA for both radiation and
chemicals greatly overestimate the risks at low dose levels. As an example,
consider the methods used by EPA to estimate cancer risks for
non-radioactive arsenic. There are no animal data and the only human data
are for lung cancer after high industrial inhalation exposures. From this
they estimate a "risk-based" standard for drinking water. This methodology
requires a lot of faith in a speculative model.

Otto
		*****************************************************
		Prof. Otto G. Raabe, Ph.D., CHP
                [President, Health Physics Society, 1997-1998]
		Institute of Toxicology & Environmental Health (ITEH)
		     (Street address: Old Davis Road)
		University of California, Davis, CA 95616
		Phone: 530-752-7754  FAX: 530-758-6140 [NEW AREA CODE]
		E-mail ograabe@ucdavis.edu