Multigenerational exposure to cobalt (CoCl₂) and WCCo nanoparticles in Enchytraeus crypticus

Cobalt and cobalt nanoparticles have many applications, for example, in the hard metal industry and in tires. The assessment of long term effects is crucial, as these materials are persistent. For many organism groups, multigenerational (MG) exposure is a highly relevant scenario for persistent materials. In this study, the biological effect of CoCl₂ (salt) and Tungsten Carbide Cobalt nanoparticles (WCCo NPs) exposure was assessed in an MG test (4 generations in spiked + 2 generations in clean soil) using the OECD/ISO standard soil test species Enchytraeus crypticus. To ensure transgenerational survival, sublethal concentrations were used to assess the MG impact. MG exposure did not increase toxicity (survival, reproduction). There was an increase in reproduction at low concentrations of Co. Materials were characterized in the exposure media and the organisms in terms of Co content. Uptake of Co-occurred from exposure to both CoCl₂ and WCCo, although without toxicity for WCCo. Cobalt from CoCl₂ exposure seemed to be stored, whereas for WCCo it was eliminated.