In the search for early biological markers to detect genetic damage, a pilot study on a hydroarsenicism-exposed group was designed. Blood and urine samples were taken from 11 individuals chronically exposed and from 13 individuals with lower exposure to the metal. Lymphocyte cultures for cytogenetic studies and HGPRT assay were done with coded peripheral blood samples, while arsenic levels and the "rec assay" in B. subtilis were determined in urine samples. The highly exposed group excreted greater amounts of As, nevertheless the rec assay showed negative results. An interesting finding is that the cell-cycle kinetics exhibited a significant difference between the groups studied, the average generation time (AGT) was longer in the highly exposed group. The percentages of chromosomal aberrations and the frequencies of sister-chromatid exchanges were similar in both populations, although complex aberrations were more frequent in the highly exposed group, which also showed a higher average variation frequency in the HGPRT assay, but the 2 latter observations were not statistically significant. The lag in lymphocyte proliferation could mean an impairment of the immune response due to arsenic exposure.

Adult↗

PubMedDate not supplied

Lymphocyte replicating ability in individuals exposed to arsenic via drinking water.

A human monitoring study was carried out to explore the effect on lymphocyte proliferation of chronic exposure to arsenic (As) via drinking water. Blood and urine samples were taken from volunteers from a town where levels of As in the drinking water averaged 412 micrograms/l, and from a matched group of individuals, with similar socioeconomic status, that drank water with As average levels of 37.2 micrograms/l. Exposure was assessed by questionnaires and by determining the levels of As in urine and water samples. The evaluation of the peripheral blood lymphocyte proliferation was done at different culture times using labelling (LI), mitotic (MI) and replication indexes (RI) as endpoints. No significant differences were seen for either LI or MI, except for MI in 72 h cultures and in LI in males and females with skin lesions vs. those without lesions. Significant differences in RI were seen for exposed females but not for males. Correlations between LI and MI showed that progression from the initial S-to M-phase is altered in exposed individuals. Arsenic exposure as well as lead and mercury affect cellular immune response, making the endpoints of cell proliferation variables of interest in population monitoring study design, since they might provide information in health impairment due to exposure, which is important in risk assessment.

Adult↗

PubMedDate not supplied