A groundbreaking review of 10 years’ worth of adverse-reaction reports filed with the Environmental Protection Agency by pesticide manufacturers, which found that pyrethrins and pyrethroids — used in thousands of supposedly “safer” pesticides — accounted for more than 26 percent of all fatal, “major,” and “moderate” human incidents reported to the EPA in 2007. Based on information from the previously unreleased EPA pesticide incident-reporting system, this investigation spurred the director of the EPA’s Office of Pesticide Programs to announce the agency would begin a broad study of the human health effects of pyrethrins and pyrethroids.