INCREASE OF BOVINE ALVEOLAR MACROPHAGE SUPEROXIDE ANION AND HYDROGEN-PEROXIDE RELEASE BY DUSTS OF DIFFERENT ORIGIN

The release of reactive oxygen intermediates (ROI) from bovine alveola r macrophages (BAM) after stimulation with heavy metal-containing dust s was investigated. BAM were obtained by postmortem lavages of bovine lungs. The dusts were collected from waste incineration, sewage sludge incineration, an electric power station, and from two different facto ries. Three quartz dusts were used as heavy metal-free controls. The d usts were fractionated by sieving and sedimentation and analyzed by el ectron microscopy, atomic absorption spectrometry (AAS), and atomic em ission spectrometry with inductively coupled plasma (AES-ICP). Incubat ion of BAM with the dusts (12.5-1000 mug/ml medium) led to concentrati on-dependent increases in ROI release. The secretion of ROI was alread y seen after 15 min and lasted throughout the experiment up to 90 min, with the exception of a waste incinerator ash, which contained the hi ghest contents of some heavy metals and where the release of ROI cease d after 60 min. We suggest that this dust exhibits simultaneously stim ulating and inhibiting effects. The ratio of the secreted O2- and H2O2 varied, depending on the dust being investigated. The release of hydr ogen peroxide correlated best, in descending order, with the content o f iron, manganese, chromium, vanadium, and arsenic in the dusts.