Elemental sulfur is frequently formed by microbial activities in terrestrial and aquatic systems under anoxic conditions. This is indicated with high sensitivity by the electron capture detector (ECD) and can render determining higher boiling organochlorines by gas chromatography using an ECD impossible. Three methods for removing sulfur were compared: treatment with copper powder, metallic mercury and tetrabutylammonium sulfite. The preparation of pyrogenic copper powder as described in the literature is unnecessary. We recommend that desulfurizing be performed with ultrasound treatment using commercially available copper powder without any pretreatment.