Sulfonated shale oils (ammonium bituminosulfonate, ichthammol, Ichthyol), shown previously to induce the directed migration of human neutrophils in Boyden chambers and to inhibit the directed migration towards the chemotactic factors C5a, LTB4, and f-Met-Leu-Phe, were studied for their effect on other neutrophil functions, which are stimulated by chemotactic factors. Like other chemotactic factors ammonium bituminosulfonate increased the adherence of neutrophils to nylon fibers, but it did not induce the release of the primary granule enzyme glucosaminidase from cytochalasin B-treated cells and it did not stimulate the production of oxygen radicals as measured by lucigenin-dependent chemiluminescence if studied under nontoxic conditions. When added together with the chemotactic tripeptide f-Met-Leu-Phe, ammonium bituminosulfonate inhibited adherence augmentation, enzyme release, and oxygen-radical production induced by the chemotactic factor. The results indicate that ammonium bituminosulfonate not only inhibited chemotactic migration but the whole spectrum of neutrophil functions induced by a chemotactic factor.