Genotoxicity biomonitoring in coal regions using wild rodent Ctenomys torquatus by Comet assay and micronucleus test

Abstract

Coal is a mixture of a variety of chemicals, especially hydrocarbons, which may give rise to polycyclic aromatic hydrocarbons (PAH). Many PAH compounds produce mutagenic and carcinogenic effects. The quality of mineral coal in Rio Grande do Sul (RS) is low and it is typically obtained by stripping operations; it represents approximately 87% of the Brazil reserves. This report concerns the application of the Comet assay to Ctenomys torquatus to detect the effects of coal, comparing the results with a micronucleus (MN) assay, both using peripheral blood. This study was performed over a 2-year period in an attempt to evaluate seasonal patterns. The wild rodent is fossorial, and its geographic distribution in RS coincides with the distribution of coal reserves. Three localitions were studied: two coal fields, Butiá (in a strip coal mine region) and Candiota (near a strip coal mine), and one control region, Pelotas (no coal). At the end of 2 years, 240 rodents had been analyzed. Our results showed that coal and derivatives induced DNA and chromosomal lesions in rodent cells that were demonstrated by Comet and MN assays. These tests also demonstrated quantitative differences between field exposures (Candiota > Butiá). The Comet assay was more sensitive and also showed a direct relationship between age and damage, and an inverse relationship between temperature and damage index.

Evaluation of the genetic alterations in direct and indirect exposures of hexavalent chromium [Cr(VI)] in leather tanning industry workers North Arcot District, South India

“…MN frequency has been found to be higher in females (Bonassi et al 2001), while gender differences in comet assay is still a matter of discussion (Heuser et al 2002;Moller 2006). The influence of age in comet assay results are also controversial and still under discussion (Silva et al 2000;Heuser et al 2002Heuser et al , 2007Moller 2006). In the present study, CA was observed to increase with age and exposure period in the exposed groups and based on age in the controls, though it was very low in the latter.…”

Effects of nanopesticide chlorfenapyr on mice

“…The CA was performed essentially as described by Singh et al (1988) and modified by Da Silva et al (2000). Each group of six mice (three females and three males) were exposed to chlorfenapyr common preparation and nanopreparation, respectively, by IP injection with different doses of 4.…”

The conservation status of the tuco-tucos, genus Ctenomys (Rodentia: Ctenomyidae), in southern Brazil

“…Populations from three localities, that correspond to two coal fields -Butiá (in a coal strip-mine region) and Candiota (near a coal strip mine) -and one control region (Pelotas), have been analyzed, and quantitative differences between field exposures have been demonstrated (Pelotas < Butiá < Candiota). Following these studies, C. torquatus was suggested as an excellent organism for use as a biomonitor and bioindicator (Silva et al, 2000b).…”

“…In the sand fields in central and southern Rio Grande do Sul, agriculture has developed rapidly since the 1960s, particularly soybean, Pinus and Eucalyptus plantations. Other important factors placing its populations at risk are environmental changes such as floods and droughts (Bertê, 2004), and coal mining, a genotoxicity factor for C. torquatus populations (Silva et al 2000b). In addition, the coal reserves that overlap the areas where this tuco-tuco lives probably have disturbed their habitats (Freitas, 1995).…”