Mutagenic testing of workers exposed to toluene-diisocyanates during plastics production process

Toluene diisocyanates (TDIs) are important industrial intermediates used in conjunction with polyester polyols as coreactants in the manufacture of polyurethane foam blocks, paints, etc. It is listed as a potential carcinogen by the National Toxicology Program (NTP) and International Agency for Research on Cancer (IARC) and is known to induce chromosomal aberrations.

The study involved 26 people, exposed to TDI during the production of plastics. The corresponding control group was comprised of 21 people coming from the same geographic area, who were never exposed to isocyanates.

The concentration of TDI ranged between 0.007 mg/m3 and 0.016 mg/m3, which amounts to 0.10-0.23 MDK (extreme value of a single substance) 0.007 mg/m3. Structural chromosome aberrations (SCA) were evaluated in 200 lymphocytes of peripheral blood. The average value was 2.6. Sister chromatid exchange (SCE) was established in 50 cells, the average being 8.127. Micronucleus (MN) was established in 500 CB, with an average of 12.07. The averages of the control group were 1.89 (SCA), 5.52 (SCE), and 4.38 (MN). The difference between the groups is of statistical significance.

The ascertained results accentuate mutagenic activity of isocyanates or their metabolic products.