# Phosphorothioic acid, O,O-diethyl O-(4-nitrophenyl) ester — US federal chemical regulatory reporting thresholds by program (CERCLA, EPCRA, CAA) For Phosphorothioic acid, O,O-diethyl O-(4-nitrophenyl) ester, cas no. is 56-38-2; cercla rq (lbs) is 10; rcra waste number is P089; regulatory categories is 1,3,4, verified against its source on 2026-08-05. - **Substance:** Phosphorothioic acid, O,O-diethyl O-(4-nitrophenyl) ester _(verified: appears in the quote below)_ - **CAS No.:** 56-38-2 _(verified: appears in the quote below)_ - **CERCLA RQ (lbs):** 10 _(verified: appears in the quote below)_ - **RCRA waste number:** P089 _(verified: appears in the quote below)_ - **Regulatory categories:** 1,3,4 _(verified: appears in the quote below)_ ## What the source says > Phosphorothioic acid, O,O-diethyl O-(4-nitrophenyl) ester | 56-38-2 | 1,3,4 | P089 | 10 (4.54) ## Source - https://www.ecfr.gov/current/title-40/chapter-I/subchapter-J/part-302/section-302.4 Last verified: 2026-08-05. Review by: 2027-08-05. Part of [US federal chemical regulatory reporting thresholds by program (CERCLA, EPCRA, CAA)](https://referencesource.org/chemical-regulatory-reporting-thresholds/).