European Agency Seeks Input on OELs for Lithium Compounds

A scientific report (PDF) published on April 1 by the European Chemicals Agency includes ECHA’s recommendations regarding occupational exposure limits for lithium compounds or salts, including lithium carbonate, lithium chloride, and lithium hydroxide. The agency was tasked by the European Commission to evaluate these lithium compounds and derive limit values for them. According to ECHA, lithium salts’ main uses are in lithium-ion battery production and in mining, as lithium salts can be extracted from mined ores. The agency’s report notes that workers in industrial settings may be exposed via inhalation and dermal routes during extraction of lithium from ores or during tasks related to preparation processes of lithium compounds.

One of ECHA’s scientific committees, the Committee for Risk Assessment (RAC), will use the agency’s new scientific report to develop its opinion on OELs for lithium compounds.

“ECHA derived [eight-hour, time-weighted average (TWA)] values for different endpoints based on human and animal data,” the report explains. “It remains for RAC to take a position on whether to base their recommendation on human or animal data and which endpoint to use as the critical one for the derivation of the [eight-hour] TWA.”

ECHA recommends eight-hour TWA OELs of 0.46 mg lithium/m3 for fertility effects, based on animal data; 11.3 mg lithium/m3 for developmental effects, based on human data; 0.35 mg lithium/m3 for developmental effects, based on animal data; 0.75 mg lithium/m3 for kidney effects, based on human data; and 0.13 mg lithium/m3 for kidney and liver effects, based on animal data. The agency also recommends a short-term exposure limit of 0.02 mg lithium/m3 for lithium hydroxide, which is intended to protect workers from respiratory tract and eye irritation from lithium hydroxide exposure over short durations. The report does not propose a biological limit value, biological guidance value, or any skin, respiratory sensitization, or skin sensitization notations for lithium compounds.

ECHA is inviting comment on its OEL proposals both to gather input on the report and to support RAC in adopting its opinion on OELs for lithium compounds. Stakeholders have until June 1 to provide comments. More information is available on the ECHA website.