40 CFR § 129.4 - Toxic pollutants.

---
identifier: "/us/cfr/t40/s129.4"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 129.4 - Toxic pollutants."
title_number: 40
title_name: "Protection of Environment"
section_number: "129.4"
section_name: "Toxic pollutants."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "D"
subchapter_name: "WATER PROGRAMS"
part_number: "129"
part_name: "TOXIC POLLUTANT EFFLUENT STANDARDS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "Secs. 307, 308, 501, Federal Water Pollution Control Act Amendments of 1972 (Pub. L. 92-500, 86 Stat. 816, (33 U.S.C. 1251 ))."
regulatory_source: "42 FR 2613, Jan. 12, 1977, unless otherwise noted."
cfr_part: "129"
---


# 129.4 Toxic pollutants.

The following are the pollutants subject to regulation under the provisions of this subpart:

(a) Aldrin/Dieldrin—*Aldrin* means the compound aldrin as identified by the chemical name, 1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-1,4 -endo-5,8-exo-dimethanonaphthalene; “Dieldrin” means the compound the dieldrin as identified by the chemical name 1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4-endo-5,8-exo-dimethanonaphthalene.

(b) DDT—*DDT* means the compounds DDT, DDD, and DDE as identified by the chemical names: (DDT)-1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane and someo,p′-isomers; (DDD) or (TDE)-1,1-dichloro-2,2-bis(p-chlorophenyl) ethane and some o,p′-isomers; (DDE)-1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene.

(c) Endrin—*Endrin* means the compound endrin as identified by the chemical name 1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4-endo-5,8-endodimethanonaphthalene.

(d) Toxaphene—*Toxaphene* means a material consisting of technical grade chlorinated camphene having the approximate formula of C<sub>10</sub> H<sub>10</sub> Cl<sub>8</sub> and normally containing 67-69 percent chlorine by weight.

(e) Benzidine—*Benzidine* means the compound benzidine and its salts as identified by the chemical name 4,4′-diaminobiphenyl.

(f) Polychlorinated Biphenyls (PCBs) *polychlorinated biphenyls* (PCBs) means a mixture of compounds composed of the biphenyl molecule which has been chlorinated to varying degrees.

[42 FR 2613, Jan. 12, 1977, as amended at 42 FR 2620, Jan. 12, 1977; 42 FR 6555, Feb. 2, 1977]