Lung sensitisation and asthma are the main health effects of 4,4′-methylenediphenyl diisocyanate (MDI). Albumin adducts (isocyanate-specific adducts) of MDI might be involved in the aetiology of sensitisation reactions. Albumin adducts of MDI were analysed in sera of diisocyanate-exposed worker with and without diisocyanate occupational asthma (DA), as well as in exposed workers with and without diisocyanate-specific IgG antibodies. In DA-positive workers and IgG-positive workers, albumin adducts were significantly higher versus workers without DA and those who were specific IgG negative. The odds ratio to be DA-positive was 57 times larger for workers with adduct levels above 23 fmol/mg. The odds ratio to be IgG-positive was 10 times larger for workers with adduct levels above 113 fmol/mg. Therefore, albumin adducts appear to be a good predictor of the biological effects. The albumin-adduct levels in workers without biological effects were in the range of the adduct levels found in previous studies of healthy MDI-factory and construction site workers.
Authors: Sabbioni G, Vanimireddy LR, Lummus ZL, Bernstein DI. ;Full Source: Archives in Toxicology. 2016 Sep 16. [Epub ahead of print] ;