Aircraft Painter / Corrosion Control: Toxic Exposure and VA Claims

Aircraft primers have long relied on chromate corrosion inhibitors, including zinc chromate and strontium chromate pigments, and bare aluminum was treated with chromate conversion coatings before priming. Spraying these primers put hexavalent chromium mist directly into the painter's breathing zone, and sanding, grinding, or blasting old primer during corrosion rework released chromate-laden dust. NIOSH considers all hexavalent chromium compounds to be occupational carcinogens and lists chromate painting among the industrial uses of hexavalent chromium. The National Cancer Institute reports that occupational exposure occurs through inhaling dusts, mists, or fumes and is associated with increased risks of lung cancer and cancers of the nasal cavity and paranasal sinuses.

Military topcoats are typically two-part polyurethane systems cured with isocyanates. Spray application atomizes the uncured paint, so painters working in hangars, paint facilities, and shipboard spaces could inhale isocyanate aerosols while overspray settled on skin and clothing. NIOSH warns that isocyanates are powerful irritants of the eyes and respiratory tract, that workers can become sensitized through breathing or skin contact, and that sensitized workers risk severe asthma attacks on any later exposure; deaths from severe asthma have been reported in sensitized workers. NIOSH also notes that animal studies associate commercial-grade toluene diisocyanate with cancer.

Before repainting, old coatings often came off with chemical strippers based on methylene chloride (dichloromethane). Painters brushed or sprayed stripper across large airframe surfaces, then scraped away the softened paint, frequently inside enclosed bays and depainting facilities where vapors concentrated. ATSDR reports that methylene chloride is used as a paint stripper, that breathing large amounts can damage the central nervous system, and that skin contact causes burning and redness. The Department of Health and Human Services has determined that methylene chloride can be reasonably anticipated to be a cancer-causing chemical, and EPA has concluded that it is likely to be carcinogenic to humans.

Surface preparation, thinning oil-based paints, and cleaning spray guns meant daily contact with mixed organic solvents such as methyl ethyl ketone, toluene, and xylene. VA specifically lists cleaning, degreasing, paint stripping, and thinning oil-based paints as the military tasks through which service members were exposed to industrial solvents. Inhaled vapors can irritate the eyes, cause drowsiness and difficulty breathing, and VA notes that severe exposure has been linked to neurological damage and certain cancers. Skin contact can cause dryness, rashes, or chemical burns. VA decides solvent-related claims on a case-by-case basis.