ECHA agrees to review cobalt classification method

The European Chemicals Agency (ECHA) has agreed to review the method used in the classification of cobalt metal as a category 1B carcinogen after industry raised questions over the proposed specific concentration limits. The agency will organise a working group to look at the methodology and will report the findings to the Competent Authorities for REACH and CLP (Caracal) on 21-22 November, a spokesperson told Chemical Watch. ECHA’s Risk Assessment Committee (RAC) adopted an opinion last year for the harmonised classification and labelling (CLH) of cobalt metal for all routes of exposure with a specific concentration limit (SCL) of 0.01% w/w. But in a document shared at the June Caracal meeting, industry association body Eurometaux probed the “appropriateness” of the methodology used to calculate the carcinogenic potency and generate the SCL. It asked ECHA for more time to evaluate these concerns, and suggested a temporary generic concentration limit (GCL) of 0.1% instead. Eurometaux launched its own review to determine whether the ‘T25’ method used to determine carcinogenic potency is suitable for substances generating local cancers via inhalation, and also more specifically, for inorganic metals. T25 is generally used for organic substances that are oral carcinogens. The first results of this review indicate that applying the T25 method results in the majority of inorganic substances being classified as ‘high-potency carcinogens’ following inhalation exposure, Eurometaux said. The question to be discussed further, it added, is “whether this is purely the result of the methodology and applied assumptions or whether this corresponds to a biological reality”. The ECHA working group could also investigate other aspects such as adjustment of exposures to dust/particulates, as the current conversion factors apply to gases and vapours, Eurometaux said.

Support for GCL

The industry body has shared the outcomes of its review with ECHA and the European Commission, and “authorities will hopefully allow these findings and resulting recommendations to be discussed by the expert group”. The cobalt metal’s adaptation to technical progress (ATP) entry will be further discussed at the next REACH committee in December. Industry hopes the committee will support an interim GCL, which “would then be revised in line with the conclusions of the expert group,” Eurometaux said. The harmonised classification and labelling of hazardous substances is updated through an ATP adopted yearly by the Commission, following RAC’s opinion. Industry has said that the proposed 0.01% SCL would hit them hard. Cobalt metal is used as a precursor in the manufacture of chemicals for batteries for various portable consumer goods, as well as the emerging market for electric vehicles. ECHA has previously said that while the potency categories based on T25 are simplistic, they could not be regarded as “wrong per se“.

Chemical Watch, 12 November 2018 ;