1. Occupational Safety and Health Administration (OSHA)
2. Agency for Toxic Substances and Disease Registry (ASTDR)
3. National Institute for Occupational Safety & Health (NIOSH)
4. EPA
5. MSDS Sources
6. Pesticides
7. DOT
8. NLM's TOXNET
29 CFR 1910.1000 (Tables of Permissible Exposure Limits)
1910 Subpart Z - Toxic and Hazardous Substances