[The personal exposure of workers in the manufacture of xylenes--in Burgas (the Neftokhim firm)].

Individual exposures were qualitatively and quantitatively characterized for "Xylols" manufacturing workers. To this end, air sampling was performed from the breathing zones of workers occupied at varying jobs, covering a representative group of 29 subjects; for comparison, 17 stationary samples were taken from work-places at the same facility. A gas chromatographic procedure specially developed for the purpose was used for identification and quantitative analysis of the substances recovered. Fatty and aromatic hydrocarbons were found to be the principal pollutants of the occupational atmosphere. The leading pollutant proved to be benzene, by virtue of its high toxicity and relatively high levels (around and above its MAC).