Hexane exposure and persistent peripheral neuropathy in automotive technicians

• Published in: Neurotoxicology (Park Forest South) Vol. 75; pp. 24 - 29
• Main Authors: Bates, Michael N., Pope, Karl, So, Yuen T., Liu, Sa, Eisen, Ellen A., Hammond, S. Katharine
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2019; Elsevier BV
• Subjects: Acquisitions & mergers; Adult; Automobiles; Automotive parts; Automotive repair; California; Cleaning; Exposure limits; Glycated Hemoglobin A - analysis; Hexanes - toxicity; Humans; Low concentrations; Male; Middle Aged; n-Hexane; Nervous system; Occupational Diseases - chemically induced; Occupational exposure; Occupational Exposure - adverse effects; Occupational Exposure - statistics & numerical data; Occupational health; Peripheral nervous system; Peripheral Nervous System Diseases - chemically induced; Peripheral neuropathy; Socioeconomic Factors; Solvents; Surveys and Questionnaires; Technicians; Toll free telephone numbers; California; Automotive repair; n-Hexane; Solvents; Occupational exposure; Peripheral neuropathy
• ISSN: 0161-813X; 1872-9711
• DOI: 10.1016/j.neuro.2019.08.008

•The first epidemiologic study of peripheral neuropathy in automotive technicans exposed to hexane.•Results generally indicate no evidence of persistent hexane-associated peripheral neuropathy.•Limited evidence of an association with exposure to solvents generally. Automotive technicians are commonly exposed to organic and chlorinated solvents, particularly through use of cleaning products. Mainly during the period 1989–2002, n-hexane was a component of some of these products. In other occupational contexts, n-hexane has been shown to be a cause of peripheral neuropathy. The purpose of the present study was to investigate whether previous exposures to low concentrations of n-hexane were a cause of persistent peripheral neuropathy in automotive technicians. Enrolled in the study were 830 San Francisco Bay Area automotive technicians. Each participant underwent a battery of tests to investigate peripheral nervous system impairment. Test results regressed against estimated hexane and total solvent exposures showed only limited evidence of association with solvent exposures. Exposures to both hexane and general solvents were well below their occupational exposure limits. Generally, our results provide reassurance about persistent peripheral neuropathic effects in automotive technicians who previously used hexane-containing automotive cleaning products. This may reflect repair processes, since the exposures occurred some years previous to the study. However, we cannot exclude the possibility that the absence of observed effect in this study may be attributable to low exposures, exposure misclassification and/or the healthy worker survivor effect.