Effects on the regional cerebral blood flow of long-term exposure to organic solvents.

Regional cerebral blood flow (rCBF, 133Xe inhalation method) was measured in 50 male paint-factory workers with a mean of 18 years of exposure to a mixture of organic solvents. A group of 50 workers in a sugar-refinery, matched for age and education, served as controls. The measurements were made during resting and during activation by mental tasks (4%; P less than 0.05) in the exposed group. Largest differences were seen in frontotemporal areas. The difference between the exposed group and and controls increased at higher dose levels. The largest rCBF-increases during mental activation were seen in the exposed group, especially in the highest exposed subjects. This finding might indicate mechanisms compensating for a somewhat defective brain function. Although the differences between the groups were generally small with considerable overlap, the results give some evidence of disturbances of brain blood flow and brain function likely related to the influence of organic solvents.