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1.
Chemosphere ; 262: 127612, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32750590

RESUMO

Widely used conazole fungicides (CFs) belong to the most frequently detected pesticides in Central European arable soils. However, data on their environmental behaviour and bioavailability to soil organisms are surprisingly scarce. In the present laboratory microcosm study prochloraz, tebuconazole, epoxiconazole and flusilazole were applied to 12 different agricultural soils at background levels. Bioaccumulation to earthworm E. andrei and lettuce L. sativa roots and leaves was evaluated in non-aged (biota exposure after addition of pesticides) and aged (exposure started three months later) systems. In contrast with expectations from ageing effect (decrease of bioavailability), bioaccumulation in E. andrei was both reduced and enhanced after ageing depending on soil properties. The reduction of bioaccumulation correlated positively to the percentage of clay but negatively to soil organic matter. The affinity of compost worm E. andrei towards organic matter where hydrophobic pesticide molecules are sorbed is discussed as a possible explanation. An apparent effect of ageing (reduction of bioavailability) was particularly observed in lettuce roots, where bioaccumulation was significantly reduced in time. However, bioaccumulation in leaves changed ambiguously in aged variants among CFs, possibly as a combined result of bioconcentration, dilution by plant growth and metabolism. This study brings first insights into how the bioaccumulation of conazole fungicides is affected by sequestration in agricultural soils. The results indicate that in complex systems, the ageing is not necessarily connected with decrease of bioaccumulation.


Assuntos
Fungicidas Industriais/metabolismo , Poluentes do Solo/metabolismo , Agricultura , Animais , Bioacumulação , Disponibilidade Biológica , Argila , Compostos de Epóxi , Fungicidas Industriais/análise , Alface/metabolismo , Oligoquetos/metabolismo , Praguicidas/análise , Silanos , Solo/química , Poluentes do Solo/análise , Triazóis
2.
Sci Total Environ ; 750: 141695, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32861076

RESUMO

Tetrabromobisphenol A (TBBPA) and hexabromocyclododecanes (HBCDs) were examined in sediments and biota species from two mangrove wetlands of the Pearl River Estuary (PRE) and the Jiulong River Estuary (JRE), South China, to investigate their distribution, bioaccumulation and biomagnification in mangrove food webs. Levels of TBBPA and ΣHBCD (sum of α-, ß- and γ-HBCDs) ranged from 0.003 to 0.31 and not detected (nd) to 1.11 ng/g dry weight in the sediments, and from 0.56 to 22.1 and nd to 56.3 ng/g lipid weight in the biota species, respectively. γ-HBCD was the major diastereoisomer in the PRE sediments, while α- and γ-HBCDs predominated in the JRE sediments. In contrast, α-HBCD was dominant in the biota. Mean enantiomeric fractions (EFs) of α-, ß- and γ-HBCDs in the sediments all followed the trend of JRE > racemic standard > PRE. A significant enrichment of (-)-α-HBCD was found in the biota (p = 0.04), with EFs in the range of 0.297-0.485. Bioaccumulations were seen for TBBPA and α-HBCD as their biota-sediment accumulation factors (BSAFs) were greater than 1. (-)-α-HBCD had significantly greater BSAFs than (+)-α-HBCD (p = 0.04), indicating the preferential bioaccumulation of (-)-α-HBCD. Biomagnification factors (BMFs) of TBBPA ranged from 0.83 to 1.51, which varied among feeding relationships and mangroves. Positive relationships were found between TBBPA concentrations and trophic levels of the biota species with trophic magnification factors of 2.17 for the PRE and 1.22 for the JRE, suggesting that TBBPA biomagnifies in the mangrove food webs. No biomagnifications were observed for ΣHBCD, α-HBCD and its enantiomers.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Bioacumulação , Biota , China , Monitoramento Ambiental , Retardadores de Chama/análise , Hidrocarbonetos Bromados/análise , Bifenil Polibromatos , Áreas Alagadas
3.
Sci Total Environ ; 751: 141264, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32871308

RESUMO

Arctic sea ice has alarmingly high concentrations of microplastics (MPs). Additionally, sea ice reduction in the Arctic is opening new opportunities for the oil and maritime industries, which could increase oil pollution in the region. Yet knowledge of the effects of co-exposure to MPs and crude oil on Arctic zooplankton is lacking. We tested the influence of MPs (polyethylene, 20.7 µm) on polycyclic aromatic hydrocarbon (PAH) bioaccumulation and oil toxicity in the key arctic copepod Calanus hyperboreus after exposure to oil with and without dispersant. Up to 30% of the copepods stopped feeding and fecal pellet production rates were reduced after co-exposure to oil (1 µL L-1) and MPs (20 MPs mL-1). The PAH body burden was ~3 times higher in feeding than in non-feeding copepods. Copepods ingested both MPs and crude oil droplets. MPs did not influence bioaccumulation of PAHs in copepods or their fecal pellets, but chemical dispersant increased bioaccumulation, especially of ≥4 ring-PAHs. Our results suggest that MPs do not act as vectors of PAHs in Arctic marine food webs after oil spills, but, at high concentrations (20 MPs mL-1), MPs can trigger behavioral stress responses (e.g., feeding suppression) to oil pollution in zooplankton.


Assuntos
Copépodes , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Regiões Árticas , Bioacumulação , Microplásticos , Petróleo/toxicidade , Plásticos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Zooplâncton
4.
Chemosphere ; 262: 127749, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805655

RESUMO

Beans of cacao (Theobroma cacaoL.) are used to produce a variety of chocolate products. Bioaccumulation of metals at toxic levels through the consumption of contaminated products has been identified as a health concern in humans. Both metal diversity and concentration as well as their interactions in the soil influence essential and non-essential metal uptake in plants; but the effects of these on bioaccumulation of metals in cacao is not understood across diverse soil types. In this study eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were investigated in 12 soil subgroups belonging to four soil orders across 15 locations in Trinidad, with the aim to investigate the effect of soil metal diversity and concentration on metal bioaccumulation in cacao. Soil metals were extracted using five methods (aqua regia, DTPA, Mehlich 3, nitric acid, and water). Cacao leaf metal concentrations were determined using the USEPA 3052 method. Metal extraction efficiency ranged between methods with aqua regia ≥ nitric acid > Mehlich 3 ≥ DTPA ≥ water across all metals. The soil extraction method that best predicted cacao leaf metal concentrations varied with the metal - Mehlich 3 or DTPA for Cd, Ni, Zn; aqua regia, Mehlich 3, or nitric acid for Pb, and water for Mn. A stepwise regression analysis showed that plant metal concentration can be predicted using soil physicochemical characteristics as well as the concentration of metals in the soil. The importance of soil type on cacao leaf metal bioaccumulation is discussed.


Assuntos
Bioacumulação , Cacau/química , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Disponibilidade Biológica , Cacau/efeitos dos fármacos , Cacau/crescimento & desenvolvimento , Humanos , Metais Pesados/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Trinidad e Tobago
5.
Sci Total Environ ; 753: 141805, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32911163

RESUMO

Seahorses, with brood pouch in adult males, are a bioindicator species that exhibit specialized reproductive strategy of "male pregnancy". Bisphenol A (BPA), one of the most pervasive endocrine-disrupting chemicals (EDCs), is hazardous for reproductive, immune, and neurological systems. However, no evidence of BPA toxicity to the male-pregnant animals is available. Herein, the reproductive toxicity of BPA was evaluated in lined seahorses (Hippocampus erectus) following exposure to environmentally relevant concentrations (10, 100, and 1000 µg/L) through physiological, histological, and transcriptional analyses. Our results indicated BPA bioaccumulation to be positively correlated with exposure doses in both sexes. Ovarian failure was only observed in the high-dose BPA treatment group, accompanied by the apoptosis of follicular cells and up-regulation of pro-apoptotic genes. However, brood pouches maintenance were surprisingly inhibited at low concentration, and transcriptomic analysis revealed disturbed profiles of genes involved in the extracellular matrix and cell-cell adhesion pathways. Interestingly, seahorse testes were less sensitive to BPA exposure than that in other teleosts. Thus, our study suggests that BPA at environmentally relevant concentrations might cause reproductive dysfunction in seahorses, potentially exerting adverse effects on the seahorse population since most of them inhabit shallow coastal areas with prevalent estrogenic contaminants.


Assuntos
Disruptores Endócrinos , Smegmamorpha , Animais , Compostos Benzidrílicos/toxicidade , Bioacumulação , Disruptores Endócrinos/toxicidade , Feminino , Masculino , Fenóis/toxicidade
6.
Sci Total Environ ; 753: 142068, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32911174

RESUMO

Biologically significant concentrations of organochlorine pesticides (OCPs) continue to be reported in wildlife populations and are of particular concern in species that occupy the highest trophic levels. Nile crocodiles (Crocodylus niloticus) are important apex predators occurring throughout much of tropical and subtropical sub-Saharan Africa, where they inhabit estuarine and freshwater habitats often impacted by contamination. In this study we examined pesticide residue accumulation in fat tissue from Nile crocodiles at Lake St Lucia, South Africa, where historically large quantities of OCPs have been used for agriculture and disease control. During 2019, we collected tail fat samples from wild (n = 21) and captive (n = 3) individuals to examine the influence of habitat, body size and sex on variations in bioaccumulation. The principal contaminant found was p,p'-DDE, a major persistent metabolite of DDT, which continues to be used in the region for combating malaria. Tissue p,p'-DDE concentrations in wild crocodiles (95-1200 ng g-1 ww) were significantly (p < 0.05) higher compared to captive individuals (23-68 ng g-1 ww) and strongly correlated (R2 > 0.70) to body length. Male (n = 14) and female (n = 7) wild crocodiles exhibited similar contaminant body burdens, however, total concentrations were substantially lower than those measured in the same population during 2016/2017. Marked differences in residue levels and profiles appear to reflect changes in food availability and dietary exposure associated with a shift in environmental conditions. These findings suggest that periods of environmental stress may be associated with enhanced toxicological risk in crocodiles. Additional work is needed to better understand contaminant accumulation and elimination mechanisms in crocodiles, and their potential effects on reproductive health.


Assuntos
Jacarés e Crocodilos , Hidrocarbonetos Clorados , Praguicidas , Animais , Bioacumulação , Feminino , Humanos , Hidrocarbonetos Clorados/análise , Masculino , Praguicidas/análise , África do Sul
7.
Sci Total Environ ; 751: 141718, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32889462

RESUMO

Antibiotics are of particular concern because of their ubiquity in aquatic environment and long-term adverse effects on aquatic organisms and humans. However, there is no information about the bioaccumulation and trophic magnification of antibiotics in subtropical environments. In this study, we determined the concentrations of 22 antibiotics to investigate their occurrence, bioaccumulation and trophic magnification in a subtropical food web from the Beibu Gulf. The total concentrations of target antibiotics ranged from 52.94-77.76 ng/L in seawater, 9.69-15.43 ng/g dry weight (dw) in sediment, and 0.68-4.75 ng/g wet weight (ww) in marine organisms, respectively. Macrolides were the predominant antibiotics in water, while fluoroquinolones were more abundant in sediment and biota samples. The total concentrations of target antibiotics in examined marine taxa descended in the order: crustacean > cephalopod > fish, with antibiotic profiles displaying distinct difference among taxa. Log BAFs (bioaccumulation factor) for antibiotics in all organisms ranged from -0.50 for erythromycin-H2O (ETM-H2O) to 2.82 for sulfamonomethoxine (SMM). Significantly negative correlation was observed between the log Dow and log BAF values (p < .05), indicating that log Dow is a good predictor of antibiotics bioaccumulation potential in marine organisms. The trophic magnification factors (TMFs) for sulfadiazine (SDZ) and enoxacin (ENX) were greater than unity, suggesting the trophic magnification of these chemicals through the food web. In contrast, enrofloxacin (ENR), ciprofloxacin (CIX), ofloxacin (OFX), norfloxacin (NOX), ETM-H2O and trimethoprim (TMP) were biodiluted in the food web from the Beibu Gulf. This study provides substantial information on the fate and trophic transfer of antibiotics in a subtropical marine ecosystem.


Assuntos
Cadeia Alimentar , Poluentes Químicos da Água , Animais , Antibacterianos/análise , Bioacumulação , China , Ecossistema , Monitoramento Ambiental , Peixes , Humanos , Poluentes Químicos da Água/análise
8.
Chemosphere ; 262: 128360, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182080

RESUMO

Mercury (Hg) is a global pollutant of concern because its organic and more toxic form, methylHg (MeHg), bioaccumulates and biomagnifies through aquatic food webs to levels that affect the health of fish and fish consumers, including humans. Although much is known about trophic transfer of MeHg in aquatic food webs at temperate latitudes in the northern hemisphere, it is unclear whether its fate is similar in biota from coastal zones of the southeastern Pacific. To assess this gap, MeHg, total Hg and food web structure (using δ13C and δ15N) were measured in marine macroinvertebrates, fishes, birds, and mammals from Patagonian fjords and the Antarctic Peninsula. Trophic magnification slopes (TMS; log MeHg versus δ15N) for coastal food webs of Patagonia were high when compared with studies in the northern hemisphere, and significantly higher near freshwater inputs as compared to offshore sites (0.244 vs 0.192). Similarly, in Antarctica, the site closer to glacial inputs had a significantly higher TMS than the one in the Southern Shetland Islands (0.132 vs 0.073). Composition of the food web also had an influence, as the TMS increased when mammals and seabirds were excluded (0.132-0.221) at a coastal site. This study found that both the composition of the food web and the proximity to freshwater outflows are key factors influencing the TMS for MeHg in Patagonian and Antarctic food webs.


Assuntos
Monitoramento Ambiental , Cadeia Alimentar , Compostos de Metilmercúrio/análise , Poluentes Químicos da Água/análise , Animais , Regiões Antárticas , Bioacumulação , Biota , Estuários , Peixes , Água Doce , Humanos , Mercúrio/análise
9.
Mar Pollut Bull ; 160: 111658, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181935

RESUMO

Twenty-three metals were evaluated in Indian Mackerel (Rastrelliger kanagurta) collected at nine fishing settlements along the coastal waters of Visakhapatnam. The muscle tissue was analyzed for metals using 7700 Series ICP-MS. The metal concentration obtained was in the order of Al > Fe > Zn > Cr > Sr > Mn > Cu > As > Se > Rb > Ag > Ba > Pb > Ni > V > Li > Cs > Cd > Co > U > Ga > Be > Ti in all samples. Most of the heavy metals were within the prescribed norms of the FAO, WHO, EC, and MHSAC, except for Al (34.66-58.55 µg/g), Cr (2.62-3.24 µg/g), Mn (0.86-1.36 µg/g), As (0.67-1.47 µg/g), and Pb (0.06-0.37 µg/g). The study reveals that the fish are not entirely safe for consumption and the pollution levels are on the borderline but can be remedied.


Assuntos
Metais Pesados , Perciformes , Animais , Bioacumulação , Monitoramento Ambiental , Índia , Metais Pesados/análise
10.
Sci Total Environ ; 748: 142484, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113683

RESUMO

The total concentration of three toxic elements (As, Cd and Pb) and five oligoelements (Cu, Mn, Mo, Ni and Se) has been determined using an original and completely validated ICP-MS method. This was applied to rice grains from 26 different genotypes cultivated in the same soil and irrigated with the same water in three different ways: by the traditional continuous flooding (CF) and by two intermittent methods, the sprinkler irrigation (SP) and the periodical saturation of the soil (SA). The adoption of SP hugely minimizes the average amounts of almost all elements in kernels (-98% for As, -90% for Se and Mn, -60% for Mo, -50% for Cd and Pb), with the only exception of Ni, whose concentration increases the average amount found in the CF rice by 7.5 times. Also SA irrigation is able to reduce the amounts of As, Mo and Pb in kernels but it significantly increases the amounts of Mn, Ni and - mainly - Cd. Also the nature of the genotype determined a wide variability of data within each irrigation method. Genotypes belonging to Indica subspecies are the best bioaccumulators of elements in both CF and SP methods and, never, the worst bioaccumulators for any element/irrigation method combination. In the principal component analysis, PC1 can differentiate samples irrigated by SP by those irrigated by CF and SA, whereas PC2 provides differentiation of CF samples by SA samples. When looking at the loading plot Ni is negatively correlated to the majority of the other elements, except Cu and Cd having negative loadings on PC2. These results allow to envisage that a proper combination of the irrigation method and the nature of rice genotype might be a very valuable tool in order to successfully achieve specific objectives of food safety or the attainment of functional properties.


Assuntos
Oryza , Poluentes do Solo , Oligoelementos , Bioacumulação , Genótipo , Oryza/genética , Solo , Poluentes do Solo/análise , Oligoelementos/análise
11.
Bull Environ Contam Toxicol ; 105(5): 777-783, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33044567

RESUMO

The capacity of Lemna minor to remediate toxic heavy metals from wastewater is reasonably well documented. In view of the pivotal role of this species in the environmental clean-up, here we evaluated the bioaccumulation potential of L. minor for cadmium (Cd), lead (Pb), and nickel (Ni) through a controlled experiment. L. minor tolerated the metals Cd, Ni, and Pb up to 0.5, 5, and 8 mg/L, respectively, and beyond these concentrations the toxicity symptoms appeared. Bio-concentration factor varied at different concentrations of heavy metals tested. Overall, L. minor showed good phytoremediation potential for all the three tested heavy metals (Cd, Ni, and Pb), though in relative terms it was more effective in extracting Ni and Cd, as compared to Pb, both in single and mixed concentrations. In view of the growing pollution in Kashmir Himalayan aquatic habitats the phytoremediation by invasive species such as L. minor promises to be one of the best choices than other native plants for cleaning up of polluted soils/water because of its fast growth rate, high abundance, easy handling, and wide distribution in Kashmir Himalayan aquatic ecosystems.


Assuntos
Organismos Aquáticos/metabolismo , Araceae/metabolismo , Bioacumulação , Metais Pesados/metabolismo , Águas Residuárias/química , Organismos Aquáticos/crescimento & desenvolvimento , Araceae/crescimento & desenvolvimento , Biodegradação Ambiental , Cádmio/análise , Cádmio/metabolismo , Ecossistema , Índia , Lagos , Chumbo/análise , Chumbo/metabolismo , Metais Pesados/análise , Níquel/análise , Níquel/metabolismo
12.
J Environ Sci (China) ; 98: 103-108, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33097140

RESUMO

Trace metal (Cr, Ni, Cu, Zn, Cd and Pb) exposures, distribution and bioaccumulation were investigated in marine organisms from Guangdong coastal regions, South China. The results showed that all of the selected metals were observed in marine organisms with a predomination of Cu and Zn. The metal exposure levels exhibited obvious variations between species with the decreasing order of crab>shellfish>shrimp>fish. The higher metals enrichment seen in shellfish and crab species primarily attributed to their living habits and the higher sediment background values of trace metals. Endpoint bioaccumulation factor (BAFfd) was used to characterize the bioaccumulation potentials of marine organisms to trace metals, of which Cu and Zn were the most accumulated elements. The exposure of trace metals in the cultured organisms was far lower than those in wild marine organisms, which is probably due to the effect of growth dilution. Comparisons with previous studies demonstrated that the concentration profiles of most trace metals declined over the last one to two decades, except Cu, that increased indistinctively.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Bioacumulação , China , Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise
13.
Environ Monit Assess ; 192(11): 704, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057810

RESUMO

Mercury (Hg) was measured in the muscle, liver, and gonads of Haemulopsis elongatus and Pomadasys macracanthus from Mazatlán (SE Gulf of California) to determine the relationships of the hepatosomatic index (HSI) and gonadosomatic index (GSI) of fish with Hg concentrations in the corresponding tissues. Health risk to consumers was assessed by using the hazard quotient (HQ), considering the average rate of fish consumption in Mexico and Hg concentration in the edible tissue. In H. elongatus, the highest Hg levels were measured in the liver (3.748 µg g-1); in P. macracanthus, the highest Hg concentration was quantified in the muscle (0.574 µg g-1). In P. macracanthus, the HSI was negatively correlated with Hg concentration in the liver; in H. elongatus, there was also a negative relationship between Hg levels in gonads and the GSI. Mean HQ values in Haemulopsis elongatus (0.005) and Pomadasys macracanthus (0.002) were below the value (HQ ≥ 1) of concern. The significant reduction of HSI and GSI with Hg increase in the liver and gonads may suggest that Hg bioaccumulation in these fish shows adverse physiological effects. Though HQ values in both species were below the unit, i.e., the consumption of the muscle from this species does not represent a health risk, it is necessary to carry out surveys of fish consumption rates in coastal areas of Mexico to do a more precise health risk assessment associated to Hg intake.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Bioacumulação , California , Monitoramento Ambiental , Mercúrio/análise , México , Medição de Risco , Poluentes Químicos da Água/análise
14.
Chemosphere ; 261: 128018, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113642

RESUMO

Highly persistent, toxic and bioaccumulative per - and polyfluoroalkyl substances (PFAS) represents a serious problem for the environment and their concentrations and fate remain largely unknown. The present study consists of a PFAS screening in sludges originating from 43 wastewater treatment plants (WWTPs) in the Czech Republic. To analyze an extended group of PFAS consisting of 32 PFAS, including GenX and other new replacements of older and restricted PFAS in sludge, a new method was optimized and validated using pressurized solvent extraction, followed by the SPE clean-up step to eliminate the observed matrix effects and LC-MS/MS. The results revealed high PFAS contamination of sewage sludge, reaching values from 5.6 to 963.2 ng g-1. The results showed that in the majority of the samples (about 60%), PFOS was the most abundant among the targeted PFAS, reaching 932.9 ng g-1. Approximately 20% of the analyzed samples contained more short-chain PFAS, suggesting the replacement of long-chain PFAS (especially restricted PFOA and PFOS). GenX was detected in 9 samples, confirming the trend in the use of new PFAS. The results revealed that significantly higher contamination was detected in the samples from large WWTPs (population equivalent > 50,000; p-value <0.05). Concerning the application of sludge in agriculture, our prediction using the respective PFAS bioconcentration factors, the observed concentrations, and the legislatively permitted management of biosolids in Czech Republic agriculture revealed that PFAS can cause serious contamination of cereals and vegetables (oat, celery shoots and lettuce leaves), as well as general secondary contamination of the environment.


Assuntos
Ácidos Alcanossulfônicos/análise , Fluorcarbonetos/análise , Contaminação de Alimentos/análise , Propionatos/análise , Esgotos/química , Poluentes do Solo/análise , Verduras/química , Ácidos Alcanossulfônicos/metabolismo , Bioacumulação , Biossólidos , Cromatografia Líquida , República Tcheca , Fertilizantes/análise , Fluorcarbonetos/metabolismo , Propionatos/metabolismo , Poluentes do Solo/metabolismo , Espectrometria de Massas em Tandem , Verduras/crescimento & desenvolvimento , Verduras/metabolismo , Águas Residuárias/química , Purificação da Água
15.
Chemosphere ; 261: 128063, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113659

RESUMO

Paralytic shellfish toxins (PSTs) are a group of natural toxic substances often found in marine bivalves. Accumulation, anatomical distribution, biotransformation and depuration of PSTs in different tissues of bivalves, however, are still not very well understood. In this study, we investigated biokinetics and biotransformation of PSTs in six different tissues, namely gill, mantle, gonad, adductor muscle, kidney, and digestive gland, in Yesso scallops Patinopecten yessoensis exposed to a toxic strain of dinoflagellate Alexandrium pacificum. High daily accumulation rate (DAR) was recorded at the beginning stage of the experiment. Most of the PSTs in toxic algae ingested by scallops were retained and the toxicity level of PSTs in scallops exceeded the regulatory limit within 5 days. At the late stage of the experiment, however, DAR decreased obviously due to the removal of PSTs. Fitting results of the biokinetics model indicated that the amount of PSTs transferred from digestive gland to mantle, adductor muscle, gonad, kidney, and gill in a decreasing order, and adductor muscle, kidney, and gonad had higher removal rate than gill and mantle. Toxin profile in digestive gland was dominated by N-sulfocarbamoyl toxins 1/2 (C1/2), closely resembled that of the toxic algae. In contrast, toxin components in kidney were dominated by high-potency neosaxitoxin (NEO) and saxitoxin (STX), suggesting that the kidney be a major organ for transformation of PSTs.


Assuntos
Dinoflagelados/metabolismo , Pectinidae/efeitos dos fármacos , Pectinidae/metabolismo , Saxitoxina/análogos & derivados , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , Biotransformação , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Saxitoxina/metabolismo , Saxitoxina/toxicidade , Toxicocinética , Poluentes Químicos da Água/toxicidade
16.
J Environ Manage ; 276: 111334, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32980611

RESUMO

Pesticides are widely used in agriculture, but they can bioaccumulate in plants, entering the food chain and potentially threaten human health. Thus, this study explored the spatiotemporal patterns of pesticide bioaccumulation in plants from soil using a spatiotemporal model. Air temperature (TAir) and relative humidity (RHAir) were selected as the principal spatiotemporal indicators to characterize the seasonal and geographical variation of the pesticide bioaccumulation factors (BAFs; i.e., the pesticide concentration ratio of plant to soil) of the leaves of common plants. The simulation results indicate that hot and dry climates typically increase the pesticide BAFs by enhancing the transpiration rate of plants. For example, the annual average BAF of alachlor was 5.75 in Arizona, while the BAFs in states with cold and humid weather, such as Maine, were below 2.00. Additionally, the monthly average BAF of alachlor during hot seasons can be double that of other seasons in the same region. For some pesticides, the simulated BAF intervals were consistent with those reported in the literature, whereas for others, the results were inconsistent. The major reasons for these inconsistencies include differences in the pesticide application scenarios, the distribution of pesticides in different compartments, and insufficient field data for some pesticides. We also applied the simulated BAFs of pesticide in plant leaves to address the seasonal and geographical health risks of herbivores, which could help regulate pesticide standards in ecological soils.


Assuntos
Praguicidas , Arizona , Bioacumulação , Humanos , Maine , Praguicidas/análise , Plantas , Solo
17.
Mar Pollut Bull ; 160: 111599, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32877770

RESUMO

Three species of mangroves and six species of salt marshes were collected from various locations along the Tuticorin coast for the estimation of metals like Cu, Cd, Pb, and Zn. The bioaccumulation of metals in mangroves is in the order of Cu > Pb > Zn > Cd, and the season-wise accumulation was higher in monsoon followed by summer, post-monsoon, and pre-monsoon seasons. The accumulation of metals in mangroves showed higher in Rhizophoraapiculata followed by Avicenniamarina, and Rhizophoramucronata. The concentration of metals in salt marshes is in the order of Pb > Zn > Cu > Cd, and the species-wise accumulation showed in the order of Suaeda maritime > Ipomoea sp. > Suaeda sp. > Spinifix littoreous > Sesuvium portacastrum > Ipomoea pes-capras. BAF in salt marhes and mangroves is as Cd < Pb < Cu < Zn and Cd < Cu < Pb < Zn, respectively.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Bioacumulação , Monitoramento Ambiental , Sedimentos Geológicos , Índia , Metais Pesados/análise , Poluentes Químicos da Água/análise , Áreas Alagadas
18.
Aquat Toxicol ; 228: 105623, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32956954

RESUMO

Trace concentrations of a number of pharmaceutically active compounds have been detected in the aquatic environment in many countries, where they are thought to have the potential to exert adverse effects on non-target organisms. Amiodarone (AMD) is one such high-risk compound commonly used in general hospitals. AMD is known to alter normal thyroid hormone (TH) function, although little information is available regarding the specific mechanism by which this disruption occurs. Anuran tadpole metamorphosis is a TH-controlled developmental process and has proven to be useful as a screening tool for environmental pollutants suspected of disrupting TH functions. In the present study, our objective was to clarify the effects of AMD on Xenopus metamorphosis as well as to assess the bioconcentration of this pharmaceutical in the liver. We found that AMD suppressed spontaneous metamorphosis, including tail regression and hindlimb elongation in pro-metamorphic stage tadpoles, which is controlled by endogenous circulating TH, indicating that AMD is a TH antagonist. In transgenic X. laevis tadpoles carrying plasmid DNA containing TH-responsive element (TRE) and a 5'-upstream promoter region of the TH receptor (TR) ßA1 gene linked to a green fluorescent protein (EGFP) gene, triiodothyronine (T3) exposure induced a strong EGFP expression in the hind limbs, whereas the addition of AMD to T3 suppressed EGFP expression, suggesting that this drug interferes with the binding of T3 to TR, leading to the inhibition of TR-mediated gene expression. We also found AMD to be highly bioconcentrated in the liver of pro-metamorphic X. tropicalis tadpoles, and we monitored hepatic accumulation of this drug using mass spectrometry imaging (MSI). Our findings suggest that AMD imposes potential risk to aquatic wildlife by disrupting TH homeostasis, with further possibility of accumulating in organisms higher up in the food chain.


Assuntos
Amiodarona/toxicidade , Bioacumulação , Disruptores Endócrinos/toxicidade , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Amiodarona/metabolismo , Animais , Disruptores Endócrinos/metabolismo , Membro Posterior/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Tri-Iodotironina/genética , Tri-Iodotironina/metabolismo , Poluentes Químicos da Água/metabolismo , Xenopus laevis
19.
Mar Environ Res ; 160: 104987, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907725

RESUMO

Ocean acidification alters physiology, acid-base balance and metabolic activity in marine animals. Near future elevated pCO2 conditions could be expected to influence the bioaccumulation of metals, feeding rate and immune parameters in marine mussels. To better understand such impairments, a series of laboratory-controlled experiment was conducted by using a model marine mussel, Mytilus galloprovincialis. The mussels were exposed to three pH conditions according to the projected CO2 emissions in the near future (one ambient: 8.10 and two reduced: 7.80 and 7.50). At first, the bioconcentration of Ag and Cd was studied in both juvenile (2.5 cm) and adult (5.1 cm) mussels by using a highly sensitive radiotracer method (110mAg and 109Cd). The uptake and depuration kinetics were followed 21 and 30 days, respectively. The biokinetic experiments demonstrated that the effect of ocean acidification on bioconcentration was metal-specific and size-specific. The uptake, depuration and tissue distribution of 110mAg were not affected by elevated pCO2 in both juvenile and adult mussels, whereas 109Cd uptake significantly increased with decreasing pH in juveniles but not in adults. Regardless of pH, 110mAg accumulated more efficiently in juvenile mussels than adult mussels. After executing the biokinetic experiment, the perturbation was sustained by using the same mussels and the same experimental set-up, which enabled us to determine filtration rate, haemocyte viability, lysosomal membrane stability, circulating cell-free nucleic acids (ccf-NAs) and protein (ccf-protein) levels. The filtration rate and haemocyte viability gradually decreased by increasing pCO2 level, whereas the lysosomal membrane stability, ccf-NAs, and ccf-protein levels remained unchanged in the mussels exposed to elevated pCO2 for eighty-two days. This study suggests that acidified seawater partially shift metal bioaccumulation, physiological and cellular parameters in the mussel Mytilus galloprovincialis.


Assuntos
Dióxido de Carbono , Metais , Mytilus , Poluentes Químicos da Água , Animais , Bioacumulação , Concentração de Íons de Hidrogênio , Metais/farmacocinética , Mytilus/química , Água do Mar , Poluentes Químicos da Água/farmacocinética
20.
Ecotoxicol Environ Saf ; 203: 111043, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888597

RESUMO

Intraspecific difference in toxicity brings uncertainty to ecological risk assessment (ERA) and water quality criteria (WQC) of chemicals. Here, we compared intraspecies sensitivity to toxicants for Mesocyclops leuckarti of which toxicity data was obtained from published literatures, and zebrafish Danio rerio of which toxicity data was done in this study). Due to the internal concentration of chemicals not measured, simplified toxicokinetic-toxicodynamic (TK-TD) models were used, and we investigated whether TK-TD parameters estimated by Bayesian method might represent the differences in sensitivity between life-stages of 2 species. The results demonstrated that the difference in TK-TD parameters (background mortality m0, no effect concentration NEC, the killing rate ks, and the dominant rate kd) could represent the toxicity difference between life-stages of individual species. The TK-TD model could predict toxicity in individual species (Cyprinus carpio L., Enchytraeus crypticus, Folsomia candida, Hyalella Azteca) exposed to different chemical concentrations and successfully extrapolate toxicity between different life stages of Mesocyclops leuckarti and Danio rerio by scaling several TK-TD parameters. The modified TK-TD model on the extrapolation toxicity of chemicals between life stages for species could be useful for the ERA and for deriving and revising WQC for chemicals.


Assuntos
Carpas/metabolismo , Copépodes/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Teorema de Bayes , Bioacumulação , Carpas/crescimento & desenvolvimento , Copépodes/crescimento & desenvolvimento , Embrião não Mamífero/metabolismo , Larva/metabolismo , Medição de Risco , Especificidade da Espécie , Toxicocinética , Peixe-Zebra/crescimento & desenvolvimento
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