Monday, March 07, 2011

EPA scientists: new studies confirm ozone's a killer

As you probably recall, the US EPA is officially reconsidering the national smog standards set by the Bush administration in 2008. The Bush EPA rejected the unanimous view of EPA’s science advisers and set a weaker standard (75 parts per billion) than the scientists had recommended (a range of 60-70). And in January 2010, the Obama EPA proposed a new smog (ozone) health standard consistent with the views of the science advisers.

Industry groups have railed against the idea of tougher standards, and the political opposition appeared to give EPA a case of cold feet. The agency has several times postponed a final decision – much to our dismay – and has booted the issue back to the science advisers. [EPA now claims it will make a final decision by the end of July.]

The advisers, in turn, have drafted a letter reiterating their support for a standard between 60-70 parts per billion.

All this has been based on a review of scientific studies through 2006.

Meanwhile, however, the EPA has continued to review the science, including post-2006 studies. And late Friday, the EPA posted its first crack at trying to make sense of the newer studies. In the jargon of the bureaucracy, this is the first draft of EPA’s “Integrated Science Assessment.”

This new report strengthens the case for a tougher smog standard than the more industry-friendly one issued by the Bush administration. This report confirms that exposure to ozone clearly sends children and adults to hospital emergency rooms. It strengthens the case that ozone can kill. [See chapter 2 of the draft]

EPA’s online summary notes that:

New material has been included in this draft, but many of the overall conclusions remain generally the same as the last NAAQS review which was completed in 2008. For example, in relation to short-term exposures, new evidence for O3-induced health effects strengthens the body of evidence for associations with premature mortality and respiratory morbidity. Also, the current ambient O3 concentrations in many areas of the US are sufficient to impair growth of numerous plant species.

Industry opponents of tougher smog standards will not like the scientific results, though they will probably now argue that EPA should delay any change in the ozone standard until it completes action on the new ozone review – something not scheduled before 2014. As the lawyers sometimes advise, if you are losing on the substance, argue process.

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