That death rates among people over 65 are higher in zip codes with more fine-particulate air pollution, as a new study from Harvard School of Public Health suggests, may not come as a surprise. But that harmful effects from that pollution were observed in areas with less than a third of the current Environmental Protection Agency (EPA) standard may be both startling, and a concern, for many.

The study, which was published online in Environmental Health Perspectives on June 3, used satellite data to measure temperature and particle levels in every zip code in New England, Science Daily reports. This technique allowed researchers to include data even from areas far from pre-existing monitoring stations and to look both at short-term and annual average exposure. That information was then cross-referenced with health data from all New England Medicare patients — some 2.4 million people — between 2003 and 2008.

The results indicate that exposure to air pollution on both the short- and long-term was significantly associated with higher death rates even in zip codes where measurements fell below EPA standards, a trend suggesting that, as with toxins such as lead, there may be no safe level of exposure.

“Most of the country is either meeting the EPA standards now, or is expected to meet them in a few years as new power plant controls kick in,” said senior author Joel Schwartz, professor of environmental epidemiology at Harvard. “This study shows that it is not enough. We need to go after coal plants that still aren’t using scrubbers to clean their emissions, as well as other sources of particles like traffic and wood smoke.”

[Science Daily]

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