Chromosomal aberrations in peripheral lymphocytes from male native miners working in the Peruvian Andes

Abstract

We analyzed the frequency of chromosomal aberrations in peripheral lymphocytes from underground miners from the Casapalca (n = 8, mean age = 45 y, range = 36 y to 55 y) and Bellavista (n = 8, mean age = 28 y, range 23 y to 34 y) high-altitude mining camps in the Peruvian Andes. This population was occupationally exposed to heavy metals such as lead and zinc as well as diesel emission particles, organic solvents and mine dust. The control groups consisted of individuals from a high altitude farming community in the Peruvian village of Tinco (n = 8, mean age = 37 y, range = 25 y to 52 y) and the sea level city of Lima (n = 14, mean age = 26 y, range = 20 y to 35 y). All individuals were male native Peruvians. A significantly higher incidence (1.88%, p < 0.05) of chromosomal aberrations (chromatid deletions and breaks, chromosome breaks and acentric fragments) were detected in lymphocytes from miners at the Casapalca camp as compared to miners from the Bellavista camp (0.5%, chromatid deletions and acentric fragments only) and the Lima sea level (0.07%, chromatid deletions only) and Tinco high altitude (no aberrations) controls. These results suggest that male native Peruvians occupationally exposed to underground mining activity have an increased frequency of chromosomal aberrations, which could be related to both age and exposure time. The increased chromosomal damage observed in the mining populations studied may be attributable to the complex mixture of genotoxic agents to which the miners may have been exposed. Chromosomal aberrations in human peripheral lymphocytes are well-established biomarkers of exposure to occupational or environmental genotoxic agents, cytogenetic analyses of lymphocytes from populations occupationally exposed to such agents having shown increased chromosomal aberration frequencies (Deknudt et al., 1973;Bauchinger et al., 1976;Lazutka et al., 1999;Topaktas et al., 2002). Underground miners are particularly exposed to complex mixtures of chemicals (e.g., heavy metals, diesel emission particles and dust), many of which are known mutagens (Johnson, 1998;Keshava and Ong, 1999;Rojas et al., 1999;Scheepers et al., 2002;Wolf et al., 2004;Donbak et al., 2005). Peruvian miners normally work at high altitude without any appropriate protective equipment, with chronic mountain sickness (excessive erythrocytosis caused by long term exposure to high altitude), silicosis and tuberculoses having frequently been reported in such workers (Paitán, 1965;León-Velarde and Arregui, 1992).Despite the fact that there are large numbers of underground miners in Peru there have been no published studies regarding the occupational exposure of these workers to genotoxic agents, one reason being the very difficult access to blood samples from these workers who are mainly native Andeans known for their aversion to blood extraction procedures.We report the results of the cytogenetic analysis of chromosomal aberrations in peripheral blood lymphocytes from a group of native Peruvian miners working at high altitud...