Harmonised Classification Review For 3,4-Dimethyl-1H-Pyrazole Underway

The European Chemicals Agency (ECHA) has launched a public consultation as part of its harmonised classification and labelling (CLH) process for 3,4-dimethyl-1H-pyrazole (3,4-DMP), a chemical substance commonly used in various industrial applications. This consultation seeks to gather further insights on the reproductive toxicity of the substance, particularly in relation to its analogue, 3,4-dimethyl-1H-pyrazol-1-ium dihydrogen phosphate (3,4-DMPP). The consultation is open until 25 September 2024.

Background On The Substance

The current classification of 3,4-DMP in Annex VI of the Classification, Labelling and Packaging (CLP) Regulation includes:

Acute Toxicity Category 4 (Oral): H302Serious Eye Damage Category 1: H318Aquatic Chronic Toxicity Category 3: H412

Belgium, the dossier submitter, has proposed expanding this classification to include additional hazards, such as Acute Dermal and Inhalation Toxicity (H312, H332), Carcinogenicity (H351), Reproductive Toxicity (H361f), and Specific Target Organ Toxicity (H373). These proposed changes aim to ensure the safe use and handling of the substance by industrial operators.

Focus Of The Current Consultation

During the RAC-70 CLH working group meeting in July 2024, experts highlighted significant similarities between 3,4-DMP and its analogue, 3,4-DMPP. Notably, reproductive toxicity studies conducted on 3,4-DMP involved relatively low doses, which may have skewed the findings. The working group expressed concerns that the absence of observed maternal toxicity in these studies could be due to insufficient exposure levels, especially considering the higher doses used in 3,4-DMPP studies, where adverse effects were reported.

This consultation invites stakeholders to comment on the proposed read-across justification between the two substances. The data collected will play a pivotal role in determining the final classification of 3,4-DMP.

How To Participate

Stakeholders, including manufacturers, downstream users, and the scientific community, are encouraged to provide comments on the reproductive toxicity data and other scientific evidence relevant to the classification of 3,4-DMP. The consultation is accessible through the ECHA’s website and closes at 23:59 Helsinki time on 25 September 2024.

Conclusion

The outcome of this consultation could have far-reaching implications for industries utilising 3,4-DMP. By participating, stakeholders can help shape the regulatory landscape, ensuring that safety measures are adequately aligned with the latest scientific data.