40 C.F.R. Appendix B to Part 118
Toxicity Endpoints for Calculating Planning Distance for Fish, Wildlife and Sensitive Environments and Public Receptors
Cite as 40 C.F.R. Appendix B to Part 118 (2026)
Category RQ (lbs.) Endpoints for public receptors LD50 Endpoints for fish, wildlife and sensitive environments using 96-hour LC50 Mammalian toxicity (oral) (mg/kg) 10% (mg/kg) Aquatic toxicity (mg/liter) 10% (mg/L) Lower Upper Lower Upper X 1 0 0.1 0.01 0 0.1 0.01 A 10 0.1 1 0.1 0.1 1 0.1 B 100 1 10 1 1 10 1 C 1,000 10 100 10 10 100 10 D 5,000 100 500 50 100 500 50