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1.
J Toxicol Environ Health B Crit Rev ; 25(8): 405-421, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36351281

RESUMO

Microplastics (MPs) are contaminants widely distributed in the environment and biota. Previously, most studies focused on identifying and characterizing microplastics in the marine environment, while their impact on freshwater ecosystems remains to be determined. This review summarizes recent findings regarding MPs physiological, immunological, and genetic effects on amphibians based upon the biological relevance of this species as indicators of freshwater pollution. Data demonstrated that MPs contamination may potentially alter various physiological processes in aquatic animals, mainly in the embryonic stages. It is worthwhile noting that adverse effects might be enhanced in synergy with other pollutants. However, amphibians might counteract the effect of MPs and other pollutants through microbiota present both in the intestine and on the skin. In addition, amphibian microbial composition might also be altered by MPs themselves in a manner that leads to unpredicted health consequences in amphibians.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Plásticos , Ecossistema , Monitoramento Ambiental , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Anfíbios
2.
Bull Environ Contam Toxicol ; 108(1): 64-70, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33723652

RESUMO

The lower basin of Coatzacoalcos River is one of the most polluted regions of the southern Gulf of Mexico. Organochlorine compounds, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, and heavy metals have been registered in this region. In the present study, genotoxicity was evaluated in the blood of giant toads (Rhinella marina) from Coatzacoalcos' rural and industrial zones, and compared with laboratory toads. Determination of the frequency of micronucleus and erythrocyte nuclear abnormalities by the light microscope and cell cycle and apoptosis by flow cytometry were used as biomarkers of genotoxicity. We found more variability in micronucleus and more nuclear buds in toads from industrial zones. Also, cell cycle alterations and an increase of apoptosis in erythrocytes were found in toads from rural and industrial zones. Multivariate statistics show that the toads from the industrial zone were more affected than toads from laboratory and rural zones.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Rios , Animais , Bufo marinus , Monitoramento Ambiental , Eritrócitos , Hidrocarbonetos Policíclicos Aromáticos/análise
3.
Ecotoxicol Environ Saf ; 208: 111493, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120261

RESUMO

In San Luis Potosí, Mexico, the exploitation of minerals has historically been carried out as an activity that has left in its path environmental liabilities, with high concentrations of heavy metals. These metals have undergone weathering by rain and wind and have moved closer to inhabited locations as is the case of Cerro de San Pedro (CSP) and Villa de la Paz (VDP). The objective of this study is to show the biological alteration of soils due to the presence of heavy metals and metalloids like Cadmium (Cd), Copper (Cu), Lead (Pb) and Arsenic (As) and to find the relationship between contamination and risk indexes. Soil samples were obtained from sites with historical records of mining activity and their surroundings. Several analyses were performed, such as pH levels, organic matter, electrical conductivity, clays, heavy metals and As. Moreover, Community Level Physiological profiling (CLPP) were conducted. The obtained evidence showed high levels of contamination by As and heavy metals in both sites (CSP: 6485.1 mg/Kg of Pb and pH of 4.4; VDP: 7188.2 mg/Kg of As and pH of 7.8). According to the Metal Pollution Index (MPI), 607.0 in CSP and 1050.5 in VDP, presented a high environmental risk, apart from, risk to human health (SQGQI) 35.8 in CSP and 131.5 in VDP. At the same time, CLPPs showed that microbiological communities were selective in taking up substrate groups, in the following order: Carbohydrates > Polymers > Carboxylic acids > Amino acids > Amines/Amides. However, a positive correlation in CSP was only found between both indexes and Amines/Amides (r = 0.46, p < 0.05), and in VDP the D-Galactonic acid-γ-Lactone with the MPI (r = 0.49, p < 0.05), and with the SQGQI (r = 0.45, p < 0.05). Although this behavior was not homogeneous, it was possible to find negative correlations between both indexes and the AWCD with other substrates, influenced by the physicochemical characteristics presented in each studied site. Consequently, according to our findings, a combined effect between the physicochemical characteristics, As, and heavy metals took place, on the metabolic activity, causing alterations to soil functions.


Assuntos
Bactérias/metabolismo , Carbono/metabolismo , Metaloides/metabolismo , Metais Pesados/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , México , Mineração
4.
Ecotoxicol Environ Saf ; 197: 110568, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32283412

RESUMO

Mining environmental liabilities (MEL) in San Luis Potosi are the result of more than 450 years of mining activity, which has contaminated the soil mainly with arsenic (As) and lead (Pb) in several areas. Risk assessments are used to estimate the possibility of the occurrence of adverse effects on human health or on ecological receptors; and the most accessible way of performing them is through probabilistic estimates such as the Latin Hypercube Sampling (LHS) model. Therefore, the aim of this study was to carry out an Integrated Probabilistic Environmental Risk Assessment (IPERA) for the estimation of health risks in infants and rodents. The mean concentrations of As and Pb in soil were significantly higher (p<0.05) in all contaminated sites than in their respective reference sites. Villa de la Paz was the site with the highest mean concentration of As (1374 mg/kg), while Charcas was the one with the highest level of Pb (12,929 mg/kg). The Hazard Quotient (HQ) was calculated and Villa de la Paz had the highest values of As in both rodents (11.994) and children (39.32), and Charcas showed the highest values of Pb in both (24.971 and 31.668 for rodents and children respectively). The cumulative hazard Index (HI) reveals there is a very significant health risk due to As and Pb exposure for both rodents and children in contaminated areas of these mining communities.


Assuntos
Arsênio/análise , Exposição Ambiental/análise , Chumbo/análise , Mineração , Poluentes do Solo/análise , Animais , Criança , Exposição Ambiental/efeitos adversos , Humanos , México , Medição de Risco , Roedores
5.
Ecotoxicol Environ Saf ; 180: 403-411, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31108417

RESUMO

The delta of the Coatzacoalcos river is a priority region for the biological conservation in the Gulf of Mexico. Environmental studies in the area have detected a complex mixture of contaminants where the presence of Persistent organic compounds (POPs) is highlighted. Deoxyribonucleic acid (DNA) integrity of biological populations are global concerns due to their ecological implications. The purpose of this study was to measure the exposure to POPs and DNA damage in nine species residing in the Coatzacoalcos river classified by taxonomic group, type of habitat and feeding habits. Total POPs concentrations (minimum and maximum) detected for all species were from 22.7 to 24,662.1 ng/g l.w; and the values of DNA damage (minimum and maximum) varied from 0.7 to 20.5 and from 6.5 to 56.8 µm (Olive tail moment and tail length respectively). Broadly speaking, reptiles, species residing in the wetland and the ones with a carnivorous diet showed higher levels of POPs and DNA damage. This study provides us with a baseline of the state of POPs contamination and shows the degree of environmental stress to which the different components of the ecosystem of the Coatzacoalcos river delta are subject to.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Dano ao DNA , Monitoramento Ambiental/métodos , Compostos Orgânicos/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/genética , Golfo do México , México , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise
6.
Environ Toxicol Pharmacol ; 103: 104280, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37741478

RESUMO

In this study, we captured cane toads (Rhinella marina) in four sites located in different regions affected by anthropogenic activities in Mexico. Subsequently we analyzed liver tissue for the presence of organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) The levels of these POPs in the toads' livers ranged from 863.2 to 3109.6 ng/g of lipid weight across all sites. A multivariate statistical analysis highlighted two sites with the highest POPs levels, with the most polluted site displaying a high level of PCBs, suggesting influence of industrial activities. The second most polluted site displayed significant amounts of OCs, linking this location to agricultural activity. Additionally, we found pesticide metabolites and isomers that allowed us to distinguish past and recent exposure events. Our observations indicate that R. marina is suitable bioindicator of sites impacted by anthropogenic activities.

7.
Ecotoxicology ; 19(7): 1238-48, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20563841

RESUMO

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-, ß-, 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.


Assuntos
Dano ao DNA , Monitoramento Ambiental/métodos , Peixes/fisiologia , Poluentes Químicos da Água/sangue , Animais , Ensaio Cometa , DDT/sangue , DDT/toxicidade , Diclorodifenil Dicloroetileno/sangue , Diclorodifenil Dicloroetileno/toxicidade , Peixes/sangue , Sedimentos Geológicos/química , Hexaclorobenzeno/sangue , Hexaclorobenzeno/toxicidade , Hexaclorocicloexano/sangue , Hexaclorocicloexano/toxicidade , Resíduos Industriais/efeitos adversos , América Latina , México , Mirex/toxicidade , Músculos/química , Bifenilos Policlorados/sangue , Bifenilos Policlorados/toxicidade , Rios , Poluentes Químicos da Água/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-20390841

RESUMO

Coatzacoalcos, Veracruz is one of the major industrial areas of Mexico. Presently, the Coatzacoalcos River and the areas surrounding the industrial complex are considered by various authors to be some of most polluted sites in Mexico. The objective of this study was to determine if earthworms could be used as indicators of environmental stress in the Coatzacoalcos industrial zone. Often, detritivores and decomposers such as earthworms are the first to be affected when the soil is contaminated. We collected soil samples to be used for persistent organic pollutants (POPs) quantification by gas chromatography. Concentrations of hexachlorobenzene, lindane and total polychlorinated biphenyls (PCBs) in the soil were above the maximum permissible limits of the Canadian Environmental Quality Guidelines (CEQG). Comet assay was conducted in coelomocytes of wild earthworms collected in Coatzacoalcos and compared with the control earthworms. We found DNA damage in earthworms from Coatzacoalcos that was significantly higher (P < 0.05) in comparison to laboratory earthworms. Earthworms are an appropriate organism to use as an indicator of environmental impact in contaminated sites. DNA damage recorded in the earthworms provides clear evidence of environmental impacts by the chemical industry on the wildlife of this region.


Assuntos
Dano ao DNA , Resíduos Industriais/efeitos adversos , Oligoquetos/efeitos dos fármacos , Compostos Orgânicos/toxicidade , Poluentes do Solo/toxicidade , Animais , Ensaio Cometa , DNA/efeitos dos fármacos , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , México , Oligoquetos/genética , Solo/análise
9.
Sci Total Environ ; 651(Pt 1): 1236-1242, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30360255

RESUMO

Persistent Organic Pollutants (POPs) are stable organic chemicals that represent a potential risk for ecosystems due to their high toxicity, persistence and biomagnification through food chains. Bioindicators in ecosystems have emerged to assess the effect of environmental pollutants. Earthworms are some of the most common bioindicator organisms in terrestrial ecosystems. The main objective of this study was to evaluate the geontoxicity of POP exposure in wild earthworms captured at different levels of urbanization throughout the lower basin of the Coatzacoalcos River (industrial, urban and rural areas). POP soil and earthworm tissue concentrations were measured via Gas-Mass Chromatography, and earthworm DNA damage was evaluated through the comet assay. The greatest concentrations of ΣPOPs, DDT and HCH were found in soil from industrial sites, followed by urban and rural areas (504.68, 383.10, 298.16; 22.6, 4.6, 2.6 and 433.7, 364, 255.6 mg/kg, respectively). Unlike other pollutants, mean ΣPCBs values were highest for industrial soil samples, followed by those from rural and urban areas (41.10, 33.97 and 12.44 mg/kg respectively). For all earthworm tissue POP analyses, the highest concentrations were found in individuals from industrial sites, followed by the urban and rural areas. Furthermore, the highest levels of DNA damage were registered in the industrial area, followed by the urban and rural areas. These assays suggest a strong links among regional soil contamination, POPs bioavailability and the potential risk of detrimental health effects for organisms that inhabit surface soil (soil life). Earthworms contribute vital ecosystem services that could be affected by these results. This work provides evidence of the potential ecological risk that exists in the Lower Basin of the Coatzacoalcos River.


Assuntos
Dano ao DNA , Exposição Ambiental , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Animais , Monitoramento Ambiental , México , Oligoquetos/genética
10.
Biomed Res Int ; 2014: 165046, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592381

RESUMO

Mining is one of the most important industrial activities worldwide. During its different stages numerous impacts are generated to the environment. The activities in the region have generated a great amount of mining residues, which have caused severe pollution and health effects in both human population and biotic components. The aim of this paper was to assess the impact of mining activities on biotic communities within the district of Villa de la Paz. The results showed that the concentrations of As and Pb in soil were higher than the national regulations for urban or agricultural areas. The bioavailability of these metals was certified by the presence of them in the roots of species of plants and in kidneys and livers of wild rodents. In regard to the community analysis, the sites that were located close to the mining district of Villa de la Paz registered a lower biological diversity, in both plants and wild rodents, aside from showing a change in the species composition of plant communities. The results of this study are evidence of the impact of mining on biotic communities, and the need to take into account the wildlife in the assessment of contaminated sites.


Assuntos
Biota , Mineração , Animais , Biodiversidade , Monitoramento Ambiental , Geografia , Metais/análise , México , Raízes de Plantas/metabolismo , Plantas/metabolismo , Roedores , Solo/química , Poluentes do Solo/análise
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