Political Economy Research Institute

The Political Economy Research Institute (PERI) is an institute at the University of Massachusetts Amherst which, according to its mission statement, "...promotes human and ecological well-being through our original research. Our approach is to translate what we learn into workable policy proposals that are capable of improving life on our planet today and in the future. In the words of the late Professor Robert Heilbroner, we at PERI “strive to make a workable science out of morality.”

The Political Economy Research Institute issues their annual Toxic 100 is a list of one hundred companies in the United States, ranked by the amount of air pollution produced and the relative toxicity of the pollutants, as determined by PERI at the University of Massachusetts Amherst. The top five companies from the 2013 index are E.I. du Pont de Nemours, Bayer Group, Dow Chemical Co., ExxonMobil and BASF.

Toxic scores are calculated by the formula:

Emissions are measured in millions of pounds. Population exposure is based on the proximity of nearby residents, and factors such as prevailing winds and height of smokestacks. Toxicity is per the US EPA's Risk-Screening Environmental Indicators.

On November 3, 2013, Precision Castparts Corp. published a report [1] in which it questioned the methodology of the Toxic 100 study. The report said that the study "assigns false high toxicity levels to the metal emissions from Precision Castparts Corp. (PCC) manufacturing facilities." However, Michael Ash, a professor of economics and public policy at the University of Massachusetts, defended the results of the PERI study, saying that the raw data came from the United States Environmental Protection Agency. [2] The study distinguished between high-toxicity and low-toxicity varieties of chromium emissions.

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