As part of its periodic review of national ambient air quality standards (NAAQS), the US EPA has recently released a final ISA for O3 and related photochemical oxidants. The 1200+ page document covers, in detail, the available evidence for (and against) ozone as the causative agent of various human health and environmental effects. The Agency concluded that “evidence integrated across controlled human exposure, epidemiologic, and toxicological studies and across the spectrum of respiratory health endpoints continues to demonstrate that there is a causal relationship between short-term O3 exposure and respiratory health effects”. The primary ozone standard (intended to protect public health) includes an 8-hour average standard set at 75 ppb, not to be exceeded more than once yearly (and the secondary ozone standard, intended to protect ‘public welfare’, is identical).

US Environmental Protection Agency. Integrated Science Assessment for ozone and related photochemical oxidants. February 2013.


The above item was taken from the March 2013 issue of Toxicology and Regulatory News which is sent automatically to members of bibra (click here for more details).

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