Toxicological potential of substances in spray-formulated degreasers and lubricants – With a literature review on asthma potentials of ammonia, maleic anhydride and methyl methacrylate

Spray-formulated engine/brake cleaners and lubricants form aerosols that can deposit in the airways where toxicity can occur. Characterisation of the ingredients' toxicity can help minimise the human risk. We recently published a database of 376 ingredient substances in 82 spray-formulated engine/brake cleaners and lubricants available in the European Union (EU) and screened them for genotoxic and carcinogenic potentials. In the current work we expand this screening to include pulmonary toxicity, neurotoxicity, hepatotoxicity and reproductive and developmental toxicity. For this we used EU harmonised classification, quantitative structure activity relationship (QSAR) models and lists of suspected asthmagens. For asthmagens we reviewed the literature. Fifteen substances had an asthma induction potential, five of which had literature to support the potential, namely: aluminium powder, ammonia, chlorine, maleic anhydride and methyl methacrylate. Other potential asthma inducers were: 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, benzyl alcohol, methyl-2-hydroxybenzoate, 1,4-dihydroxybenzene, 2-aminoethanol, 2-aminopropanol, 1,2-benzisothiazol-3(2H)-on, hexyl dihydrogen phosphate and diethanolamine. The number of substances with potential for the other toxicities are: acute toxicity when inhaled (8 substances), aspiration toxicity (13), neurotoxicity (13), reproductive/developmental toxicity (34) and hepatotoxicity (76). The fractions of products containing substances with potential for the toxicities were: asthma (18% of the products), acute toxicity when inhaled (12%), neurotoxicity (55%), reproductive/developmental toxicity (63%) and hepatotoxicity (52%). Finally, we discuss substances to be prioritised as of highest concern. In conclusion, we identified a substantial toxic potential with the employed screening methods. The data can be used in safe-by-design substitution of potentially toxic substances and inform hazard assessment of spray-formulated engine/brake cleaners and lubricants.