Sister-chromatid exchange decreased frequency

Rescue and safety workers have also been studied. Nishiwaki et al. (2001) studied 27 male rescue team staff and 30 police officers, 3-45 months after the event. The study subjects showed decreased performance on the digit span test however, no effects on stabilometry and vibration perception threshold were found. Li et al. (2004) followed 27 male firefighters and 25 male police officers three years after the attack for genotoxic effects. They found an elevated frequency of sister chromatid exchanges in lymphocytes of the victims which were related to the percentage of ChE inhibition observed just after the attack. 

Isoprene is nonmutagenic in bacterial test systems. However, isoprene forms adducts of blood hemoglobin in mice and rats. Increases in frequency of sister chromatid exchanges in bone marrow cells and in levels of micronucleated polychromatic erythrocytes were detected. Based on these results, isoprene is expected to induce tumors at multiple sites in exposed mice. Developmental toxicity has been indicated in mice, including decreased fetal body weight and ossification these impacts were not noted in rats. 

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