40 CFR § 721.10371 - Butanoic acid, 3-mercapto-,1,1′-[2-(hydroxymethyl)-2-(substituted-1-oxoalkoxy)methyl)-1,3-propanediyl] ester (generic).

---
identifier: "/us/cfr/t40/s721.10371"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 721.10371 - Butanoic acid, 3-mercapto-,1,1′-[2-(hydroxymethyl)-2-(substituted-1-oxoalkoxy)methyl)-1,3-propanediyl] ester (generic)."
title_number: 40
title_name: "Protection of Environment"
section_number: "721.10371"
section_name: "Butanoic acid, 3-mercapto-,1,1′-[2-(hydroxymethyl)-2-(substituted-1-oxoalkoxy)methyl)-1,3-propanediyl] ester (generic)."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "R"
subchapter_name: "TOXIC SUBSTANCES CONTROL ACT"
part_number: "721"
part_name: "SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "15 U.S.C. 2604, 2607, and 2625(c)."
regulatory_source: "49 FR 35018, Sept. 5, 1984, unless otherwise noted."
cfr_part: "721"
---


# 721.10371 Butanoic acid, 3-mercapto-,1,1′-[2-(hydroxymethyl)-2-(substituted-1-oxoalkoxy)methyl)-1,3-propanediyl] ester (generic).

(a) *Chemical substance and significant new uses subject to reporting.* (1) The chemical substance identified generically as butanoic acid, 3-mercapto-,1,1′-[2-(hydroxymethyl)-2-(substituted-1-oxoalkoxy)methyl)-1,3-propanediyl] ester (PMN P-10-136 and S-18-5, Chemical A) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section.

(2) The significant new uses are:

(i) *Industrial, commercial, and consumer activities.* Requirements as specified in § 721.80(f). It is a significant new use to use the substance other than as a monomer for acryl-based ultra-violet (UV)-curing coatings, inks, and adhesives or the confidential use described in the significant new use notice S-18-5.

(ii) *Release to water.* Requirements as specified in § 721.90(b)(4) and (c)(4) (N = 2).

(b) *Specific requirements.* The provisions of subpart A of this part apply to this section except as modified by this paragraph.

(1) *Recordkeeping.* Recordkeeping requirements as specified in § 721.125(a), (b), (c), (i), and (k) are applicable to manufacturers, importers, and processors of this substance.

(2) *Limitations or revocation of certain notification requirements.* The provisions of § 721.185 apply to this section.

[77 FR 25275, Apr. 27, 2012, as amended at 85 FR 68000, Oct. 27, 2020]