---
kind: "section"
citation: "40 C.F.R. § 721.1660"
title: "40"
number: "721.1660"
heading: "Benzidine-based chemical substances."
url: "https://uscodex.org/cfr/40/721.1660"
---

# §721.1660. Benzidine-based chemical substances.

- (a) **Chemical substances and significant new uses subject to reporting.**
  - (1) The benzidine-based chemical substances listed in Table 1 and Table 2 of this section are subject to reporting under this section for the significant new uses described in [paragraph (a)(2)](#a-2) of this section.
  - (2) **The significant new uses are—**
    - (i) For each of the chemical substances listed in Table 2 of this section, any use other than use as a reagent to test for hydrogen peroxide in milk; a reagent to test for hydrogen sulfate, hydrogen cyanide, and nicotine; a stain in microscopy; a reagent for detecting blood; an analytical standard; and, additionally for Colour Index (C.I.) Direct Red 28 (Congo Red) (CAS No. 573-58-0), an indicator dye.
    - (ii) **For the chemical substances listed in Table 1 of this section—** Any use.
- (b) **Specific requirements.** The provisions of [subpart A](/cfr/40/subpartA.md) of this part apply to this section except as modified by this [paragraph (b)](#b).
  - (1) **Revocation of certain notification exemptions.** The provisions of [§ 721.45(f)](/cfr/40/721.45.md?p=f) do not apply to this section. A person who imports or processes a chemical substance identified in [paragraph (a)(1)](#a-1) of this section as part of an article for a significant new use described in [paragraph (a)(2)](#a-2) of this section is not exempt from submitting a significant new use notice.
  - (2) [Reserved]

## Notes

### Amendments

[79 FR 77909, Dec. 29, 2014]

### Authority

Authority: 15 U.S.C. 2604, 2607, and 2625(c).

### Source

Source: 49 FR 35018, Sept. 5, 1984, unless otherwise noted.

### Amendments

[79 FR 77909, Dec. 29, 2014]