Proposed hazard classification for two diphenylamines

Reaction products of diphenylamine with nonene, branched (BNPA) and Benzenamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene are UVCB-type substituted diphenylamines.

Substituted diphenylamines are found in lubricants, greases, cutting fluids and hydraulic fluids, and are used in the manufacture of plastics. They are found in a wide range of products, including washing liquids, vehicle care products, paints, perfumes and air fresheners, as well as lubricants in engine oils and brake fluids. These substances are not currently covered by harmonised European classifications under the CLP Regulation on classification, labelling and packaging of products. ANSES therefore assessed their reprotoxic properties for human health and their toxicity for organisms in the aquatic environment, with a view to proposing a harmonised classification at European level.

Proven effects on human fertility and development

Regarding the assessment of reproductive toxicity, these two substances do not have an identical data set. A read-across approach based on structural and toxicological similarities was therefore applied to them in order to compensate for unavailable toxicological information. This consolidated the analysis, which concluded that there were established effects on fertility and development for both substances.

Effects on female fertility have been demonstrated in several reproduction studies in rats. Developmental effects have also been reported in rodents, characterised mainly by effects on the central nervous system. On this basis, both substances are presumed to be toxic to human reproduction.

Chronic toxicity for aquatic organisms

Concerning environmental hazards, the studies available for BNPA and Benzenamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene show chronic toxicity for aquatic organisms and indicate, in both cases, that species of Daphnia are the most sensitive. However, the concentrations that induce harmful effects are specific to each substance. A stricter classification has been assigned to BNPA on the basis of the available data.

Both classification proposals submitted for public consultation

For all these reasons, ANSES proposes that BNPA and Benzenamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene should be classified and labelled under the CLP Regulation as follows:

BNPA:

• Reproductive toxicity; Category 1B (H360FD: May damage fertility. May damage the unborn child).
• Hazardous to the aquatic environment, Category 1 (H140, Very toxic to aquatic life with long lasting effects).

Benzenamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene:

• Reproductive toxicity; Category 1B (H360FD: May damage fertility. May damage the unborn child).
• Hazardous to the aquatic environment, Category 2 (H411, Toxic to aquatic life with long lasting effects).

The harmonised classification proposals for BNPA and Benzenamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene were submitted for public consultation on the ECHA website on 4 March 2024, for a two-month period, to give all stakeholders the opportunity to comment on these proposals by providing any additional scientific arguments and information they may have. Comments can be sent via a dedicated form on the ECHA website.

Following this consultation stage, ANSES will be asked to respond to the comments received. The initial proposal, comments and ANSES's responses to them will then be submitted to ECHA’s Committee for Risk Assessment, which will issue its opinion on the classification of BNPA and Benzenamine, N-phenyl‑, reaction products with 2,4,4-trimethylpentene.

Based on this opinion, the European Commission will draft regulatory texts allowing the chosen classifications to be included in the CLP Regulation.