Occupational exposure to aldrin: clinical and laboratory findings.

279-282. The paper reports the relation of neurological symptoms and EEG findings to the concentration of HEOD in whole blood. Fifteen men who had been making aldrin in a fertilizer plant for up to five years were examined in the last month of exposure. Three of them were followed up for seven months after cessation of exposure. Eight were examined on one occasion two years after their last period of exposure to aldrin. Some men in whom the HEOD concentrations in whole blood were above 0·10 ppm had symptoms of poisoning but these were absent in others with higher (0·25 ppm) concentrations. In three men severely affected at the time of cessation of exposure, symptoms ceased within seven months. Symptoms that were still present in others two years later are ascribed to occupational exposure to lindane. After cessation of exposure, the concentration of HEOD in whole blood fell slowly, initially at a rate corresponding to a biological half-life of 50 to 150 days. Later, it fell more slowly, so that two years after the cessation of exposure the concentrations of HEOD in whole blood were still higher than in the general Hungarian population.