From The Mercury:
Testing shows that efforts by two area narrow tube factories to reduce or eliminate the amount of a potentially carcinogenic chemical they emit into the air has resulted in lower levels of that chemical, thus reducing the area's cancer risk, state officials said.
The Pennsylvania Department of Environmental Protection, which has been sampling and analyzing the area's air since 2004, issued the report...At the time, two local plants, Superior Tube on Germantown Pike in Lower Providence and Accellent on Seventh Avenue in Trappe, both used significant amounts of TCE as a de-greaser in their industrial processes. The emissions from both plants were within the limits set by the permits issued to them by the DEP.
Part of a family of chemicals known as volatile organic compounds, TCE is recognized by California as a known carcinogen, while the U.S. Environmental Protection Agency classifies it only as a suspected carcinogen. TCE also falls into a category of pollutants officially dubbed hazardous air pollutants.
In February of 2008, Superior announced it would abandon TCE completely in favor of an alternative chemical, n-propyl bromide, which is also a volatile organic compound but is not classified as a hazardous air pollutant.
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