Surface and skin decontamination of aliphatic isocyanates in an experimental study.
Bello-D; Woskie-S; Strecher-R; Stowe-M; Sparer-J; Liu-Y
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia. Fairfax, VA: American Industrial Hygiene Association, 2004 May; :61
Isocyanates may cause contact dermatitis and skin irritation or sensitization leading to asthma. Dermal exposure to aliphatic isocyanates in auto body shops is very common. However, little is known about the efficiency of available commercial products in decontaminating isocyanates. This experimental study evaluated decontamination efficiency of aliphatic isocyanates for six skin (ZEP, GOJO, STOKO painters hand cleaners, STOKO Culpran barrier cream, CLI-DTAM safe solvent, and polypropylene glycol PPG) and seven surface (water, 10% soap/water, isopropanol, isopropanol/tergitol/water 5/20/75, CLI-ammonia, Pine-Sol general purpose cleaner, generic ammonia-based cleaner) decontaminants used in or recommended for the auto body industry. The two major decontamination mechanisms were studied separately for each decontaminant: (1) destruction of free isocyanate groups via chemical reactions with active hydrogen components of decontaminant was studied via measuring reaction kinetics in a vial; (2) decontamination efficiency by physical and mechanical removal processes was evaluated from triplicate isocyanate spikes on 10-cm diameter aluminum foil. Two model isocyanates, butyl isocyanate and Bayer’s N3300 isocyanurate each at 1 x 10-3 N, were used for the reaction kinetic study. N3300, spiked at 0.33 and 3.3 ug NCO/in2, was used to study the efficiency of mechanical removal processes. Isocyanates were quantified using NIOSH method 5525 and high performance liquid chromatography. Considerable differences were observed among surface and skin decontaminants in their rate of isocyanate consumption, of which those containing free amine groups performed the best and PPG the worst. Overall, Pine-Sol and CLI-ammonia solutions were the most efficient surface decontaminants, operating primarily via chemical reaction with the isocyanate group. All tested skin decontaminants performed similarly, accomplishing decontamination primarily via mechanical processes and removing up to 80% of isocyanates in one wiping. Limitations of these skin decontaminants are discussed and alternatives presented. In vivo testing and evaluation are needed to further assess the efficiency and identify related determinants.
Skin-diseases; Isocyanates; Skin-irritants; Contact-dermatitis; Dermatitis; Sensitization; Bronchial-asthma; Decontamination; Chemical-reactions; Ammonium-compounds
Research Tools and Approaches: Exposure Assessment Methods
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia