Risk Guidelines Under Fire

The Office of Management and Budget (OMB) has proposed a plan for standardizing risk assessments across the U.S. government, an idea that has considerable merit but could be manifested in various negative ways, according to some agency representatives.  The original OMB draft bulletin was designed to set minimum standards for the scientific quality of federal agency assessments of risk to human health, safety, or the environment. Areas affected include regulation of pollutants, approval of new pharmaceuticals, and development of safety systems for chemical plants. A June 5, 2006 article in C&E News (www.cen-online.org) suggests that the primary target of this directive is the EPA. The most notable example of what many consider to be an issue politicized on all sides has been the determination of a preliminary drinking water standard for perchlorate. The involvement of the NRC in the debate helped find a compromise, but the issue of whether sound science received a fair hearing on all sides remains contentious.  More on the potential effects on public health policy is presented in C&E News.

ACS Perchlorate Symposium

Readers interested in the ongoing debate over health effects derived from exposure to trace perchlorate in the environment should tune into the panel discussion scheduled as part of the American Chemical Society National Meeting Technical Program at the Washington DC Convention Center.  The Session titled Perchlorates: Science and Policy, was to run Wednesday, August 31 and Thursday, September 1, with the panel discussion scheduled for the end of the day Thursday.  Details on the meeting are available at www.acs.org. 

Program topics are reported to include a review of the previously (2005) published NRC recommendations on perchlorate ingestion, and views on perchlorate policy from industry, academic, and public perspectives.

Minute Dose Health Risk Issues

The July 25, 2005 edition of the Wall Street Journal featured a front page article by Peter Waldman on the issue of the effects of minute doses of chemical agents on hormonal processes that impact human health. The evaluation of effects of substituents in amounts as low as parts per trillion "challenges an axiom of toxicology stated by the Swiss chemist Paracelsus nearly 500 years ago:  The dose makes the poison." 

There are many complicating factors. Some chemical agents seem to require the presence of a secondary agent in order to manifest biological effects. Accurate analytical measurement of part per trillion levels of analytes presents significant challenges. And the possibility or likelihood of natural occurrence of some agents (such as perchlorate) commonly regarded as "industrial chemicals" further complicates the "risk vs. benefit" debate. 

For more information go to  www.wsj.com.

Journal AWWA - Perchlorate Status Report

The American Water Works Association has published a thorough examination of the current status of perchlorate regulation in their May 2005 issue in an article titled "Data gains push perchlorate nearer to regulatory determination." Risk assessment and risk reduction can be treated in some greater detail since the National Academy of Sciences released the NRC report in January of 2005.

The recent firming-up of perchlorate risk science and occurrence data has gone a long way toward meeting two critical information needs for possible Federal regulation, but the progress has fallen short of addressing the lingering uncertainties faced by water suppliers about how to respond to the high-profile contaminant.

http://www.awwa.org/communications/journal/2005/May/News/0505wtrbeat.pdf

[Editing note:  a clarification needs to be applied to the following comment from the last page of the article: "presence of perchlorate in milk lowers the iodide content and may impair thyroid development in infants." In actuality, the iodide content is not affected by perchlorate; however, perchlorate competes with iodide for uptake from the blood into the thyroid gland. Assuming iodine sufficiency, the typical  human physiology allows an adaptive response to such conditions. Developmental effects on fetal and infant subjects have been the subject of considerable study.]