Exposure to persistent organic pollutants (POPs) and DNA damage as an indicator of environmental stress in fish of different feeding habits of Coatzacoalcos, Veracruz, Mexico

Abstract

The region of Coatzacoalcos, Veracruz hosts one of the largest and most important industrial areas of Mexico and Latin America. Industrial development and rapid population growth, have triggered a severe impact on aquatic ecosystems of the region. The aim of this study was to determine the levels of POPs in sediment and in muscle tissue of five fish species from different trophic levels in downstream residents of the Coatzacoalcos River, and their integration with DNA damage in the fish, evaluated with the comet assay in whole blood as a biological indicator of stress, in order to obtain a baseline of the ecological condition of the region. The compounds detected in sediment and in muscle tissue were hexachlorobenzene (HCB), α-, β-, γ-hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), mirex and polychlorinated biphenyls (PCBs). Sediment concentrations of these pollutants (except for mirex) exceeded the values of protection provided by international guidelines, suggesting a potential risk to aquatic life in the region. DNA damage recorded in the fish species is evidence of exposure to a mix of genotoxic pollutants, which combined with exposure to POPs, reflects the degree of environmental stress of aquatic organisms in the region. The results of this study show the importance of determining the presence of contaminants in the environment, the bioaccumulation in tissues and their effects on exposed organisms, providing an integrated approach in assessing the health of aquatic ecosystems.

Exposure Assessment to Persistent Organic Pollutants in Wildlife: The Case Study of Coatzacoalcos, Veracruz, Mexico

“…Based on these backgrounds and results registered in this study, it is possible to postulate the Eisenia earthworms as POPs biomonitors in terrestrial ecosystems because earthworms play a major role in facilitating pivotal interactions within ecosystems through the mixing and translocation of soil constituents, or serving as a conduit for contaminants to predators at higher trophic levels (Harris et al, 2000;Langdon et al, 2003). Earthworms have been used extensively in ecotoxicology like biomonitors (Fitzpatrick et al, 1992;Goven et al, 1993;Reinecke & Reinecke, 1998;Espinosa-Reyes et al, 2010) to assess the effects of diffuse contaminants present in soils. Finally, when doing a POPs biomonitoring in terrestrial ecosystems, it is important to take into account the following factors: a) species susceptibility difference; b) soil type; c) species behavior; d) exposure time; e) pollutant toxicity; f) when using pesticides consider the applying method.…”

“…It is complicated to make a comparison between crab species because they have different etiology and habitants, however, because most crab species are detritivores, we consider them as a good option to do studies related to POPs exposure. There are several studies on earthworms with ecotoxicological background mainly focused on effects at population levels (lethality), at both laboratory controlled conditions (Heimbach, 1984;Ma & Bodt, 1993;Kula, 1995, Morrison et al, 2000 as in field ones (Thompson, 1970;Tomlin, 1981;Edwards & Brown, 1982;Haque & Ebing, 1983;Potter et al, 1994;Espinosa-Reyes et al, 2010), however, there are a few studies where exposure to POPs are evaluated, Jones and Hart (1998) revised works related to exposure of different earthworms species to various pesticides-Benomyl, Carbaryl, Carbendazim, Carbofuran, Chlordane, Methiocarb, Parathion, Pentachlorophenol, Phorate, Propoxur, Thiophanateme-. These same authors mentioned that earthworms of the Eisenia type are the most resistent to the pesticides previou s l y m e n t i o n e d .…”

“…In similar studies it has been found that exposure to POPs may cause several effects (Espinosa-Reyes et al, 2010;González-Mille et al, 2010). In addition, one must consider that Coatzacoalcos organisms are exposed to other types of pollutants in addition to POPs whose collective action could well increase the magnitude of the effects.…”

Significant accumulation of persistent organic pollutants and dysregulation in multiple DNA damage repair pathways in the electronic-waste-exposed populations

“…Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation (González-Mille et al, 2010). In the past, pesticides use were the main source of POPs.…”

Acute toxicity and cholinesterase inhibition of the nematicide ethoprophos in larvae of gar <i>Atractosteus tropicus</i>(Semionotiformes: Lepisosteidae).

“…In this regard, most of the studies concerning species-specific ecotoxicology, and its use to establish limits and regulations have been carried out in North America and Europe (US-EPA 1986, OECD 2007. Some studies has been carried out in South America and Mexico (Akaishi et al 2002, de la Torre et al 2005, Azevedo et al 2009, González-Mille et al 2010), but information is scarce for Central America.…”