Developments and interlaboratory study of the analysis of short-chain chlorinated paraffins

Participants were requested to analyse test solutions and extracts of various matrices with their method of choice. Thirty-three laboratories participated (9-22 per round), of which 55-81% were able to submit data. Large differences in results between laboratories were found (CVs 23-137%) but results improved over time, while the levels in the test materials decreased. In the last round acceptable CV values (<25%) were obtained for the test solution. In the last round, results obtained by the GC-ECNI-LRMS technique varied most, which is disconcerting as this technique is most commonly applied. We strongly suggest to continue monitoring comparability of laboratories to assess consensus in SCCP analysis, with a focus on quantification procedures applied.