Cytogenetic investigation of thallium-poisoned people: pilot study

Thirteen blood samples of thallium-poisoned people were cytogenetically investigated. The thallium concentration in blood varied from 25 to 2700 microg/L. The mean frequency of chromosomal aberrations in the poisoned group significantly exceeded our control level (7.08+/--2.19% and 2.03+/--0.25, p<.001). The rate of single fragments was significantly higher in poisoned group (7.77+/-2.68% and 1.59+/-0.23%, p<.001) while the frequencies of other types of chromosomal aberrations were similar in both groups. It is possible that thallium is an S-dependent clastogenic agent because the majority of the structural aberrations are of the chromatid type. Irrespective of mechanisms, damage to genetic material was revealed in thallium-poisoned people.