BIOLOGICAL MONITORING OF OCCUPATIONAL EXPOSURE IN THE CHROMATE PIGMENT PRODUCTION INDUSTRY

A survey of occupational exposure to hexavalent chromium in chromate pigment production was undertaken in factories producing lead chromate (PbCrO//4) and strontium chromate (SrCrO//4). Exceptionally high levels of chromium in blood (387-4160 nmol l** minus **1) and urine (41-1250 nmol nmol** minus **1 creatinine) as well as skin and nasal lesions, were discovered amongst the workforce at the strontium chromate plant. These contrasted with occupationally unexposed levels of less than 20 nmol l** minus **1 and less than 1 nmol nmol** minus **1 creatinine, respectively, and led to the continuation of the biological monitoring programme. At the same time, improved working practices and respiratory protection equipment were introduced. A steady elimination of chromium from whole blood with a half-life of approximately 24 days was found. This elimination rate was confirmed over a 14-day period when the workforce were completely removed from exposure.