4,4'-methylenedianiline in hydrolysed serum and urine from a worker exposed to thermal degradation products of methylene diphenyl diisocyanate elastomers.
A 45-year-old mechanic employed in blowing hot air (350°-600°C) onto the surface of a polyurethane methylene diphenyl diisocyanate (MDI) conveyer belt developed dyspnoea, rhinoconjunctivitis and fever.
The illness was suggestive of an MDI-associated illness, compatible with both immediate hypersensitivity and a complement-mediated immune-complex reaction.
In his serum there were specific IgG and IgE antibodies against MDI and other isocyanates, and high values of circulating immune complexes.
The patient's blood and urine samples were analysed for the presence of 4,4'-methylenedianiline (MDA) in hydrolysed urine and plasma.
MDA was derivatized to amides using pentafluoropropionic acid anhydride (PFPA).
Gas chromatography-mass spectrometry determinations were made monitoring the (M-20 ; M=molecular mass) fragments from the MDA-PFPA and the [2H2]MDA-PFPA derivative.
The first urine sample was obtained 22 h and the last sample 114 h after start of exposure.
The urine concentrations of MDA were corrected for creatinine.
The half-time of MDA was 70-80 h. The first serum sample was obtained 19 h and the last sample 1967 days after the start of exposure.
The half-time was 21 days, which suggests the presence of MDTI/MDA plasma protein adducts in the exposed worker.
Mots-clés Pascal : 4,4p-Méthylènedianiline, Diisocyanate organique, Elastomère, Toxicité, Médecine travail, Exposition professionnelle, Surveillance biologique, Urine, Etude cas, Homme
Mots-clés Pascal anglais : Organic diisocyanate, Elastomer, Toxicity, Occupational medicine, Occupational exposure, Biological monitoring, Urine, Case study, Human
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 95-0425912
Code Inist : 002B03L06. Création : 01/03/1996.