# Arsenic oxide As2O5 — US federal chemical regulatory reporting thresholds by program (CERCLA, EPCRA, CAA) For Arsenic oxide As2O5, cas no. is 1303-28-2; cercla rq (lbs) is 1; rcra waste number is P011; regulatory categories is 1,4, verified against its source on 2026-08-05. - **Substance:** Arsenic oxide As2O5 _(verified: appears in the quote below)_ - **CAS No.:** 1303-28-2 _(verified: appears in the quote below)_ - **CERCLA RQ (lbs):** 1 _(verified: appears in the quote below)_ - **RCRA waste number:** P011 _(verified: appears in the quote below)_ - **Regulatory categories:** 1,4 _(verified: appears in the quote below)_ ## What the source says > Arsenic oxide As2O5 | 1303-28-2 | 1,4 | P011 | 1 (0.454) ## 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/).