Solvent Toxicity

1. Solvents are typically liquids which can dissolve another material, usually organic in nature such as acetone, although the most common solvent we come in contact with on a daily basis is water.

2. Solvent exposure is particularly common in industries such as dry cleaning, printing, plastics and chemical manufacturing. However, solvent exposure in all workplaces and also in the home is a common occurrence.

3. Solvents can be categorised in a variety of ways. Some are solely hydrocarbon based, such as hexane, whilst others may contain additional functional groups such as ethanol. Their usefulness as solvents is based in part related to their volatility, which decreases with increasing molecular weight.

4. The presence of functional groups, carbon chain length and degree of saturation are some of the factors which dictate their toxicity; and this can vary significantly. For example, n-hexane is known to cause peripheral neurotoxicity whereas as 1,1,2- trichloroethylene is an animal carcinogen.

5. Inhalation is the most common route of exposure, where the vapours can irritate the mucous membranes of the lungs or cause systemic damage elsewhere in the body. Skin contact is another important route of exposure where the solvent can either be absorbed through the skin into the blood stream to cause systemic effects, or cause local dermatological effects.

6. The main toxicological consequences will depend on the duration and exposure. Acute effects are caused by single exposures to a large amount of solvent. The onset of symptoms includes dermatitis, drowsiness and headaches.

7. Long term, repeated exposure to solvents can affect other organs which include the brain and nervous system, the kidneys and liver.