Vehicle Mechanic: Toxic Exposure and VA Claims

For much of the 20th century, brake linings and clutch facings were manufactured with asbestos. The VA specifically lists clutch facings and brake linings, called friction products, among the asbestos-containing products veterans may have worked with. Grinding or beveling new linings, sanding worn surfaces, and blowing dust out of brake drums and clutch housings with compressed air all released asbestos fibers into the mechanic's breathing zone. The National Cancer Institute notes that studies of automobile mechanics exposed to asbestos through brake repair are limited, but the overall evidence suggests there is no safe level of asbestos exposure.

Motor pools and maintenance shops relied on solvent parts washers and vapor degreasers to strip grease from engine components, bearings, and tools, and TCE was a standard degreasing solvent for metal equipment for decades. Mechanics were exposed by inhaling vapors while leaning over open tanks and by direct skin contact when dipping and scrubbing parts by hand. The National Cancer Institute states that prolonged or repeated exposure to TCE causes kidney cancer and may be associated with increased risks of non-Hodgkin lymphoma and, possibly, liver cancer. TCE from military degreasing operations also contaminated soil and groundwater near many current and former bases.

Draining crankcases, rebuilding engines, and handling oily parts put used engine oil in constant contact with a mechanic's skin. The ATSDR explains that used mineral-based crankcase oil differs from new oil because engine heat and pressure create additional chemicals, including polycyclic aromatic hydrocarbons (PAHs), along with metals from engine wear and traces of fuel. Some PAHs have been identified as cancer-causing agents, and long-term skin exposure to used crankcase oil caused skin cancer in laboratory mice. ATSDR also reports that mechanics exposed to used oil from many vehicles have experienced skin rashes, blood effects such as anemia, headaches, and tremors.

Running engines are part of a mechanic's diagnostic toolkit, and vehicles were routinely started, idled, and revved inside maintenance bays, during recovery operations, and in staging areas. NIOSH designates diesel exhaust a potential occupational carcinogen, with exposure occurring through inhalation and skin or eye contact, and notes lung tumors in animal studies along with eye irritation and pulmonary function changes in exposed workers. Mechanics who spent years in enclosed or poorly ventilated motor pools often accumulated far more exhaust exposure than drivers or passengers ever did.