RESUMO
Accidents involving fuels and oil spills are among the main sources of hydrocarbons to the marine ecosystems and often damage the biota. Diesel and bunker oil are two examples of fuels with broad application that release hydrocarbons to the aquatic environment and little is known about their toxicity on tropical organisms. This study aimed to assess the toxicity of the water-soluble fraction (WSF) of diesel and bunker oils to neotropical marine invertebrates. Commercial fuels were purchased for WSF extraction, analyzed for total petroleum hydrocarbons (TPH), and polycyclic aromatic hydrocarbons (PAHs), and acute and chronic toxicity determined. The WSF analyzed contained varied levels of TPH and PAHs mixtures, especially low molecular weight PAHs; bunker WSF presented higher amounts of TPH and PAHs. Both WSFs tested produced significant mortality of the brine shrimp Artemia salina, affected the reproduction rate of the copepod Nitokra sp, and impaired the embryo-larval development of the mussel Perna perna and of the sea urchin Lytechinus variegatus. In general WSF from diesel was more toxic to the organisms tested, but bunker WSF was more toxic to embryos of L. variegatus. Toxicity started from concentrations of 3% WSF, which can be environmentally relevant after an oil spill, indicating that marine biota may be adversely affected in short term.
Assuntos
Copépodes , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Ecossistema , Hidrocarbonetos/toxicidade , Petróleo/toxicidade , Poluição por Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
The development of oil and gas production together with the fruit production in nearby areas of North Patagonia, Argentina, suggests aquatic pollution scenarios which include permanent oil pollution combined with short events of pesticides application. It has been reported that oil hydrocarbons activate the aryl hydrocarbon receptor (AhR) pathway in the rainbow trout, Oncorhynchus mykiss, and that the insecticide Chlorpyrifos (CPF) interacts with these effects. Thus, it is interesting to investigate whether hydrocarbons and insecticides, applied by separate or combined, can affect fish health and reproductive signaling by acting on different nuclear receptors' regulatory pathways. To study this kind of interactions, we exposed juvenile rainbow trout to water accommodated fraction (WAF) of crude oil (62 µg L-1 TPH) for 48 h and subsequently exposed the livers ex vivo to the insecticide Chlorpyrifos (CPF) (20 µg L-1) for 1 h. We analyzed the mRNA expression of nuclear receptors and proteins involved in detoxifying, antioxidant, immune and apoptosis responses by qRT-PCR. We also performed histopathological analysis. WAF induced the expression of the androgen (AR) and the Liver X receptor (LXR) by 8- and 3-fold, respectively. AR induction was reversed by subsequent exposure to CPF. The progesterone receptor (PR) and glucocorticoid receptor (GR) were increased 2-fold and 3-fold by WAF respectively, while estrogen and mineralocorticoid receptors were not affected. GR was also induced by CPF with an additive effect in the WAF-CPF treatment. The antioxidant genes, gamma glutamyl transferase (GGT), superoxide dismutase (SOD1) were induced by WAF (2-3-fold). WAF upregulated the ATP Binding Cassette Subfamily C Member 2 (ABCC2, MRP2) (4-fold) and downregulated alkaline phosphatase. WAF also induced the inflammatory interleukins (IL) IL-8, and IL-6 and the anti-inflammatory IL-10, while CPF induced the inflammatory tumor necrosis factor (-α) and IL-6, and activated the intrinsic apoptotic pathway through the induction of caspases 3 and 9. Both, WAF and CPF downregulated the expression of the extrinsic apoptosis initiator caspase 8 and the inflammatory caspase 1. In conclusion, WAF hydrocarbons alter O. mykiss endocrine regulation by inducing AR, PR and GR. The subsequent exposure to CPF reverses AR, suggesting a complex interaction of different pollutants in contaminated environments, WAF hydrocarbons alter liver metabolism by inducing the expression of LXR, GR, antioxidant and detoxifying enzymes, and both inflammatory and anti-inflammatory cytokines, and causing mild hepatic steatosis. CPF activates inflammatory and stress responses associated with the induction of inflammatory cytokines together with apoptosis initiator and executioner caspases.
Assuntos
Clorpirifos/toxicidade , Hidrocarbonetos/toxicidade , Oncorhynchus mykiss/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Argentina , Clorpirifos/metabolismo , Hidrocarbonetos/metabolismo , Imunidade , Inseticidas/toxicidade , Fígado/efeitos dos fármacos , Petróleo/metabolismo , Poluição por Petróleo , Receptores Citoplasmáticos e Nucleares/metabolismo , Poluentes Químicos da Água/metabolismoRESUMO
Sublethal effects of water-accommodated fraction (WAF) from crude oil of Neuquén basin, Northern Patagonia-Argentina, were examined on both antioxidant and detoxification system of Hyalella curvispina adults collected in Los Barreales (LB) lake and in an oil-polluted stream (DS). The effects of WAF exposure during 6, 24 and 48 h were evaluated in the glutathione content (GSH) and glutathione S-transferase (GST), catalase (CAT) and cytochrome P450 (CYP450) activities. Populations from DS and LB showed not only different basal GSH content and enzyme activities but also different behavior to WAF exposure. LB population exposed to WAF showed a significant increase in GSH content, CAT and CYP450 activities, compared to control group. DS population presented high basal levels in CAT and CYP activity compared with LB population, but their response to WAF exposure was minor. Amphipods from DS, chronically exposed to hydrocarbons, were adapted to their environment.
Assuntos
Anfípodes/efeitos dos fármacos , Hidrocarbonetos/toxicidade , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Anfípodes/metabolismo , Animais , Catalase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Água , Poluição Química da Água/efeitos adversosRESUMO
The Paso del Norte region is characterized by its dynamic industries and active agriculture. Throughout the years, urban and agricultural soils from this region have been exposed to xenobiotics, heavy metals, and excess of hydrocarbons. In this study, samples of urban [domestic workshops (DW)] and agricultural-intended (AI) soils from different sites of Ciudad Juárez, Mexico were evaluated for their fertility, element content, and microbial diversity. Chemical analyses showed that nitrites, nitrates, P, K, Mg, and Mn were predominantly higher in AI soils, compared to DW soils (pâ¯≤â¯0.05). The composition of soil microbial communities showed that Proteobacteria phylum was the most abundant in both soils (67%, pâ¯≤â¯0.05). In AI soils, Paracoccus denitrificans was reduced (pâ¯≤â¯0.05), concurring with an increment in nitrates, while the content of nitrogen was negatively correlated with the rhizobium group (r2â¯=â¯-0.65, pâ¯≤â¯0.05). In DW soils, the Firmicutes phylum represented up to ~25%, and the relative abundance of Proteobacteria strongly correlated with a higher Cu content (r2â¯=â¯0.99, pâ¯≤â¯0.0001). The monotypic genus Sulfuricurvum was found only in oil-contaminated soil samples. Finally, all samples showed the presence of the recently created phylum Candidatus saccharibacteria. These results describe the productivity parameters of AI soils and its correlation to the microbial diversity, which are very important to understand and potentiate the productivity of soils. The data also suggest that soils impacted with hydrocarbons and metal(oid)s allow the reproduction of microorganisms with the potential to alleviate contaminated sites.
Assuntos
Microbiota , Microbiologia do Solo , Poluentes do Solo/toxicidade , Solo/química , Agricultura , Bactérias/classificação , Poluição Ambiental , Hidrocarbonetos/toxicidade , Metagenômica , Metais Pesados/toxicidade , México , Nitrogênio/análise , Análise EspectralRESUMO
Chronic kidney disease (CKD) affects the kidneys, and in severe cases is considered as end-stage renal disease which can only be treated by dialysis and transplantation. Tierra Blanca city has a higher CKD rate compared to other Mexican cities, but its principal cause has not been found yet. Main factors related to CKD are carbonated beverage consumption, diabetes, obesity, hypertension, heat stress, dehydration, and intoxication by pesticides, heavy metals, and/or hydrocarbons. The aim of this work was to evaluate hydrocarbon pollution in Tierra Blanca domestic fresh-water related to CKD and to integrate this information with other main factors in order to suggest precautionary actions taking account of key actors. We found hydrocarbons in the water wells of the city and the presence of other risk factors, which creates a perfect storm for CKD. Additionally, key actors were identified in order to follow precautionary principles related to CKD cases in Tierra Blanca.
Assuntos
Hidrocarbonetos/toxicidade , Rim/efeitos dos fármacos , Insuficiência Renal Crônica/induzido quimicamente , Poluentes Químicos da Água/toxicidade , Monitoramento Ambiental , Humanos , Hidrocarbonetos/análise , México , Medição de Risco , Fatores de Risco , Poluentes Químicos da Água/análise , Poluição da ÁguaRESUMO
Contamination of soil with petroleum is common in oil-producing areas across the tropical regions of the world. There is limited knowledge on the sensitivity of endogeic tropical earthworms to the contamination of soil with total petroleum hydrocarbons (TPH) present in crude oil. Pontoscolex corethrurus is a dominant species in tropical agroecosystems around oil-processing facilities. The sensitivity of P. corethrurus to soil artificially contaminated with "Maya" Mexican heavy crude oil was investigated through avoidance and acute ecotoxicity tests, using the following measured concentrations: 0 (reference soil), 551, 969, 4845, 9991 and 14,869 mg/kg. The avoidance test showed that P. corethrurus displayed a significant avoidance behavior to heavy crude oil at a concentration of 9991 mg/kg or higher. In contrast, acute toxicity tests indicate that the median lethal concentration (LC50) was 3067.32 mg/kg; however, growth (weight loss) was more sensitive than mortality. Our study revealed that P. corethrurus is sensitive to TPH, thus highlighting the importance of P. corethrurus for petroleum ecotoxicological tests.
Assuntos
Oligoquetos/fisiologia , Petróleo/toxicidade , Poluentes do Solo/toxicidade , Animais , Ecotoxicologia , Hidrocarbonetos/toxicidade , México , Poluição por Petróleo/análise , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Testes de Toxicidade AgudaRESUMO
The Sinos River is one of the most polluted rivers in Brazil. The purpose of this work was to monitor the presence of some pesticides and hydrocarbons as well as the genotoxic and cytotoxic potential on HEp-2 cells from water samples collected at seven sites in the Sinos River Basin (SRB), southern Brazil. Nine samples were taken from the three main rivers in the SRB and used as a solution to dilute the HEp-2 cell culture medium after microfiltration. Twenty-four pesticides and 19 hydrocarbons were measured. Cytotoxicity was assessed by methyl thiazolyl tetrazolium (MTT) and neutral red (NR) assays, in which cells were exposed to different concentrations of the water samples for 24 h. Genotoxicity of the microfiltrated raw water samples was assessed by comet assay after 6 and 24 h of exposure. Among the chemicals analyzed, only the 2,4-D, dichloromethane, tetrachloroethene, chloroform, bromodichloromethane, styrene, and toluene were detected, but they were all lower than the limit established by Brazilian regulations. Twenty samples from a total of 60 had a cytotoxic effect in the MTT assay and 30 in the NR assay. The comet assay indicated the presence of genotoxic substances in the water at the seven locations monitored. Temporal and spatial variation was observed in the cytotoxicity and genotoxicity assays. Results indicated that the water in all stretches of the SRB is contaminated and it can cause harmful effects to humans and to the aquatic biota. This HEp-2 cell-line approach can be an additional tool for environmental monitoring.
Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos/toxicidade , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Ácido 2,4-Diclorofenoxiacético/análise , Ácido 2,4-Diclorofenoxiacético/toxicidade , Brasil , Ensaio Cometa , Hidrocarbonetos/análise , Praguicidas/análise , Rios/química , Poluentes Químicos da Água/análiseRESUMO
Hydrocarbons are the main components of diesel oil and are toxic for the majority of plants. A few plant species, known as phytoremediators, are tolerant of hydrocarbons and can survive the stressful conditions of soils contaminated with diesel oil. Canavalia ensiformis, a plant species that is well distributed throughout the tropics, possesses advantageous features for a potential resistance to soil contamination, such as fast growth and a deep root system. Thus, the aim of the present study was to evaluate the tolerance of C. ensiformis when it was exposed to soil contaminated with diesel oil. Seedlings were subjected to two treatments: contaminated soil (CS) (95 ml/kg of diesel oil) and non-contaminated soil (NCS) for a period of 30 days; its growth, morphology, anatomy, and physiology were analyzed. Despite the high level of toxicity, some individuals were able to survive in CS. These plants had root apical meristems with high levels of mitosis and were able to issue new roots with more developed aerenchyma tissue. Because the surviving plants presented no marks of cellular damage on the organs formed (root and leaves) during the experiment, the species capacity of growth on CS was confirmed. Although, long-term field experiments, applying different contaminant concentrations, should be considered to infer about the species resistance and use as phytoremediator.
Assuntos
Canavalia/crescimento & desenvolvimento , Gasolina/análise , Hidrocarbonetos/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Canavalia/efeitos dos fármacos , Gasolina/toxicidade , Hidrocarbonetos/toxicidade , Modelos Teóricos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/toxicidadeRESUMO
During an environmental impact study of an accidental oil spill in the Campeche Sound in October 2007, we examined the helminth parasites of the benthic flatfish Cyclopsetta chittendeni as well as the concentrations of hydrocarbons and heavy metals in the sediment. The aim of this study was to determine the potential effects of these contaminants on the helminth communities of the flatfish. A total of 427 hosts were examined, and 16,895 helminths, representing 17 species, were obtained from two surveys (March and July, 2008). Statistically significant negative associations were observed between the hydrocarbons and helminth parasite abundances using multivariate methods. The results suggest that in October 2007, the oil spill had a strong negative effect on these helminth communities. However, after five months, the impacted stations were re-populated by both the flatfish and helminths. The most likely explanation for this rapid recovery is the rescue effect from non-impacted habitats to impacted stations.
Assuntos
Doenças dos Peixes/parasitologia , Linguado/parasitologia , Helmintos/efeitos dos fármacos , Hidrocarbonetos/toxicidade , Poluição por Petróleo/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Animais , Monitoramento Ambiental/métodos , Golfo do México , Hidrocarbonetos/efeitos adversos , México , Análise MultivariadaRESUMO
Crude oil and petroleum products have a wide variety of hazardous components with high toxicity and low biodegradability. Certain dyes change their colors by intercepting electron transfer reactions during the transformation processes. This study applied resazurin and 2,6-dichlorophenol-indophenol indicators for a rapid screening biodegradation capability and toxicity response to various petroleum products such as motor oil, diesel, gasoline, and phenol. Colorimetry tests were performed in test tubes, and the absorbance values were measured over time. We observed different discoloration profiles after degradation tests using Bacillus subtilis inoculum. Phytotoxicity assays were also performed to compare colorimetric screening assays with a conventional toxicity testing with plants (seed germination). The results indicated that biotransformation of oils can increase its overall toxicity. Intermediate byproducts can be formed through biodegradation and thereby increase the toxicity of oils. The assessment of acute toxicity has shown that phenol is extremely toxic to petroleum-biodegrading microbial communities. Low molecular-weight gasoline was considered biodegradable, but it also exhibited a high acute toxic effect, mainly due to its high solubility and the presence of more volatile compounds that can penetrate cells and potentially damage cellular structures.