Abstract
The contents of 20 proprietary thinner products were identified using product material safety data sheets (MSDS). Disclosure of the identity of individual ingredients in MSDS was variable, with nonspecific descriptors (such as paraffinic hydrocarbon solvent) being used fairly commonly. Disclosure of formulation content of ingredients was also sometimes confusing, as ranges were used (such as 10–30%) rather than specific proportions. The 20 thinner products contained 83 disclosed specific, trade name, or generically described chemical solvent ingredients. These 83 ingredients were made entirely of 32 different solvents, which came under 6 classes: alcohols, aromatic hydrocarbons, esters, glycol ethers, ketones, and mixtures. The presence of hazardous ingredients in thinner products continues. It is a common perception among workers that thinners are safe to use, and that the different types of thinners are equivalent. This is not the case. The proportion of ingredients can vary significantly, and the hazards may change accordingly. Educational programs should be developed to inform users that thinners are different materials made of different ingredients, and that they have different hazards that should be treated with proper respect.