Biological monitoring of a worker acutely exposed to MBOCA.
Osorio AM; Clapp D; Ward E; Wilson HK; Cocker J
Am J Ind Med 1990 Nov; 18(5):577-589
The effects of acute exposure to 4,4'-methylene-bis-2-chloroaniline (101144) (MBOCA) were assessed in a polyurethane worker who was exposed to an accidental spill in a facility which produced MBOCA cured plastic products. The employee was sprayed over his upper body and extremities with molten MBOCA. The subsequent environmental and medical evaluation of this episode included serial urinary MBOCA samples over a two week period to allow the calculation of a biological half life for the compound. The worker experienced a very high dose of MBOCA as judged by urinary MBOCA levels; peak value was 1700 parts per billion four hours post exposure. There were no acute symptoms or other observable laboratory abnormalities. The kinetic evaluation resulted in a biological half life for MBOCA in urine of approximately 23 hours; thus, assuming a one compartment model, approximately 94% of the initial dose would be eliminated within four days. The authors conclude that the data suggest that biological monitoring of urine MBOCA concentrations may miss peak levels following acute exposure unless analyses are performed in a timely fashion. Health and safety recommendations included installation of warning systems or lockout devices to prevent MBOCA release and annual medical surveillance of exposed workers for bladder cancer.
NIOSH-Author; Biological-monitoring; Industrial-medicine; Carcinogens; Occupational-exposure; Worker-health; Acute-exposure; Case-studies; Urinalysis; Chlorinated-anilines; Biologic-half-life;
Author Keywords: biological monitoring; 4-4'-methylene-bis-2-chloroaniline; MBOCA; kinetic analysis; polyurethane casting; dermal absorption; urinary excretion
Dr. Ana Maria Osorio, California Dept. of Health Services, Occupational Health Program, Room 504, 2151 Berkeley Way, Berkeley, CA 94704
American Journal of Industrial Medicine