http://www.atsdr.cdc.gov/toxfaq.html
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ToxFAQs was developed by the Toxic Substances and Disease Registry (ATSDR) to summarize known information about hazardous substances. Information for these summaries is excerpted from the ATSDR Toxicological Profiles and Public Health Statements. Answers most frequently asked questions about exposure to hazardous substances found around hazardous waste sites.