Post-Brexit mandatory classifications that diverge from EU CLP generally less strict, analysis finds

Britain’s initial set of mandatory classifications tend to be less strict where they diverge from categorisations under the EU CLP, an analysis by Chemical Watch News & Insight has shown.

The finding raises the possibility that companies operating in Britain (England, Scotland and Wales) could gain a competitive advantage over EU competitors because of less stringent regulation under the GB CLP, with potential for negative impacts on human health and the environment. However, companies operating in both jurisdictions may find themselves hampered by additional complexity and administrative burdens as they may need to, for example, label products differently.

Britain set mandatory classifications under post-Brexit chemicals legislation for the first time on 20 October. The classifications, covering 98 substances, stem from opinions of ECHA’s Risk Assessment Committee (RAC) published in 2019 and 2020. The EU already set classifications for the same substances in 2021 and 2022 through the adaptation to technical progress (ATP) process.

For 15 of the 98 substances affected, the classifications are not wholly aligned. And a Chemical Watch News & Insight analysis shows that the EU classification is stricter than the British equivalent for 12 of those 15 diverging substances (see table), or 80% of the time.

HSE rejected some RAC conclusions

The extent of the divergence varies considerably from substance to substance.

At one extreme, the EU classification follows the RAC recommendation, while Britain has no classification for the same endpoint. For example, the biocide azamethiphos has a category 2 carcinogenicity classification in the EU, but no classification for carcinogenicity in Britain.

In a technical report on RAC’s azamethiphos opinion published in 2021, Britain’s national regulator for chemicals the Health and Safety Executive (HSE) concluded that classification was unwarranted because tumours seen in relevant studies "could be regarded as incidental findings". There was no clear dose-response relationship and no statistical significance, the agency added.

The HSE did agree with RAC on classifications for azamethiphos for six other endpoints, however. 

For other substances, the divergence is minimal. For the pesticide trifloxystrobin, for example, the EU and Britain both have a category 2 specific target organ toxicity with repeat exposure classification (STOT RE 2). However, in the EU the classification is for effects in the kidney as well as in the blood, whereas in Britain it is only for effects in the blood.

In all 15 cases of divergence, the deviation from the relevant RAC opinion originates in the HSE technical reports, published in 2021. The HSE agreed with its own technical report recommendations in all of its subsequent opinions, published in 2022. The ministerial decisions likewise have not deviated from those 2021 recommendations.

There are "limited" instances of difference between the British classifications, the RAC opinions, and the equivalent EU classifications, an HSE spokesperson said. "While the UK recognises the importance of the EU single market, as a third country, the UK must now make its own decisions regarding the classification and labelling of hazardous chemicals," they added.

They also said that where HSE proposes a less severe classification than RAC, "this does not necessarily mean that the overall classification proposed is less protective for human health and the environment".

Divergence remains a concern

Regulatory divergence from the EU as a result of Brexit remains a hot topic in UK political circles.

The Labour Party, which is projected to win the next general election that must be held by January 2025, said in October that it will aim to minimise divergence on REACH to increase protections from hazardous chemicals that are "falling behind due to a real lack of data and resources in the UK system".

Further mandatory classifications are in the pipeline, with ministers expected to take decisions for another 26 substances in the first quarter of next year.

This article was updated on 9 November to include comments from the HSE.