Chronic solvent exposures are often caused by the inhalation of solvent vapors, or the ingestion of diluted solvents, repeated over the course of an extended period.
Some solvents can damage internal organs like the liver, the kidneys, the nervous system, or the brain. The cumulative brain effects of long-term or repeated exposure to some solvents is called chronic solvent-induced encephalopathy (CSE).
Chronic exposure to organic solvents in the work environment can produce a range of adverse neuropsychiatric effects. For example, occupational exposure to organic solvents has been associated with higher numbers of painters suffering from alcoholism. Ethanol has a synergistic effect when taken in combination with many solvents; for instance, a combination of toluene/benzene and ethanol causes greater nausea/vomiting than either substance alone.
Some organic solvents are known or suspected to be cataractogenic. A mixture of aromatic hydrocarbons, aliphatic hydrocarbons, alcohols, esters, ketones, and terpenes were found to greatly increase the risk of developing cataracts in the lens of the eye.