RESUMO
This article reviews evidence for the public health impacts of coal across the extraction, processing, use, and waste disposal continuum. Surface coal mining and processing impose public health risks on residential communities through air and water pollution. Burning coal in power plants emits more nitrogen oxides, sulfur dioxide, particulate matter, and heavy metals per unit of energy than any other fuel source and impairs global public health. Coal ash disposal exposes communities to heavy metals and particulate matter waste. Use of coal in domestic households causes public health harm concentrated in developing nations. Across the coal continuum, adverse impacts are disproportionately felt by persons of poor socioeconomic status, contributing to health inequities. Despite efforts to develop renewable energy sources, coal use has not declined on a global scale. Concentrated efforts to eliminate coal as an energy source are imperative to improve public health and avert serious climate change consequences.
Assuntos
Poluição do Ar/efeitos adversos , Minas de Carvão , Carvão Mineral/efeitos adversos , Exposição Ambiental/efeitos adversos , Saúde Pública/estatística & dados numéricos , Poluição da Água/efeitos adversos , Humanos , Fatores de Risco , Estados UnidosRESUMO
Water quality has declined globally due to increased contamination of aquatic ecosystems. The use of fish genotoxicity biomarkers may improve and complement parameters for environmental risk assessment. The aim of this study was to assess the genotoxicity of samples collected from streams of the Jordão River, a tributary of the Paranaíba River, Brazil with different levels of metal contamination, utilizing a native fish species to determine the sensitivity and viability of implementing a useful, reliable technique for routine biomonitoring programs. Chemical analysis of water and sediments collected from different sites indicated that a gradient of contamination existed as evidenced by different concentrations of metals detected. After chronic exposure to contaminated samples, micronucleus (MN) frequencies in fish erythrocytes were measured and correlation with environmental parameters determined. Sites where the water concentrations of the metals aluminum (Al), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) were high indicating a greater genotoxic potential of these elements. At the samples collected from the urban zone, a gradual increase was found for chromium (Cr), cadmium (Cd) and nickel (Ni) indicative of adverse impacts of discharge of urban effluents. Data demonstrated that Astyanax altiparanae, used in the test, exhibited a reliable sensitivity for detection of genotoxic consequences attributed to exposure to water samples collected near the discharge of industrial and domestic waste.
Assuntos
Characidae/metabolismo , Monitoramento Ambiental/métodos , Testes de Mutagenicidade/veterinária , Rios/química , Poluição da Água/efeitos adversos , Animais , Biomarcadores/análise , Brasil , Qualidade da ÁguaRESUMO
The interpretation of biomarkers in natura should be based on a referential of expected values in uncontaminated conditions. Nevertheless, to build a reference data set of biomarker responses in estuarine areas, which receive chronic pollution loads due to their transition position between continent and sea, is impossible. In this context, the aim of the present work was to propose the use of laboratory recovery period to define a baseline for the measurement of sperm DNA damage by Comet assay in the estuarine prawn Palaemon longirostris. For that, sperm DNA integrity was observed after both a passive (i.e. 20 days in a clean environment) and an active (i.e. forced renewal of spermatophores) recovery of wild P. longirostris specimens from the Seine estuary, in laboratory conditions. Then, the levels of sperm DNA damage recorded within the P. longirostris population of the Seine estuary, during six campaigns of sampling from April 2015 to October 2017, have been interpreted according to the defined threshold values. The results showed a persistence in the level of DNA damage after 20-day in clean environment with the passive recovery. This strategy was inconclusive to reach a baseline level but it revealed the lack of DNA repair mechanisms. For the active recovery, a decrease of 54% of the level of DNA damage has been observed after the first renewal of spermatophores and this level stabilized after the second renewal. On the basis of this second strategy, we defined a mean basal value of sperm DNA damage of 54.9 A.U. and a maximum threshold of 69.7 A.U. (i.e. 95 %CI). The analysis of the results using the reference value highlighted significant abnormal sperm DNA damage within the native population of P. longirostris from the Seine estuary on all stations during the six-sampling campaigns.
Assuntos
Dano ao DNA/genética , DNA/genética , Monitoramento Ambiental/métodos , Palaemonidae/fisiologia , Espermatozoides/fisiologia , Poluição da Água/efeitos adversos , Animais , Ensaio Cometa/métodos , Estuários , França , MasculinoAssuntos
Água Potável/normas , Água Subterrânea/química , Resíduos de Praguicidas/análise , Poluição da Água/prevenção & controle , Abastecimento de Água/normas , Dinamarca , Política Ambiental/legislação & jurisprudência , Humanos , Recém-Nascido , Resíduos de Praguicidas/efeitos adversos , Política , Saúde Pública/normas , Desenvolvimento Sustentável/legislação & jurisprudência , Poluentes da Água/efeitos adversos , Poluentes da Água/análise , Poluição da Água/efeitos adversos , Poluição da Água/economia , Purificação da Água/economia , Abastecimento de Água/economiaRESUMO
We report preliminary findings of a large outbreak of human leptospirosis with 36 confirmed/probable and 583 suspected cases from June-August 2018, linked to contaminated water bodies in Northern Israel. There was a travel-associated case in Germany; additional cases are being investigated in other countries. The presumed chain of transmission, implicating wild boar and cattle, raises multiple challenges for risk assessment, risk management and risk communication currently being addressed by a public health response team.
Assuntos
Surtos de Doenças , Leptospira/classificação , Leptospirose/epidemiologia , Poluição da Água/efeitos adversos , Animais , Bovinos , Epidemias , Feminino , Alemanha , Humanos , Israel/epidemiologia , Leptospirose/diagnóstico , Leptospirose/transmissão , Saúde Pública , Gestão de Riscos , Suínos , Viagem , Microbiologia da ÁguaRESUMO
Populations of macro-algae and sessile invertebrates have precipitously declined in urbanised coastal waters in Australia since European occupation. Responses of healthy subtidal sessile assemblages to cumulative impacts and types of urban impacts were measured in one of the most polluted estuaries in Australia - the Derwent Estuary - by transplanting sessile communities established on pavers to locations adjacent to marinas, sewerage outfalls, fish farm cages, and stormwater discharges, each with associated controls. Reef communities translocated to sites adjacent to central urban pollution sources (within 5â¯km of Hobart) lost canopy-forming algae. Fish farms, marinas, and storm water drains were all characterised by higher filamentous algal cover than their controls. Marinas were associated with losses in canopy and foliose algae. Restoration of subtidal reef near highly urbanised areas is unlikely to be successful until current pollution levels are dramatically reduced.
Assuntos
Organismos Aquáticos/fisiologia , Biota , Estuários , Poluição da Água/efeitos adversos , Animais , Aquicultura , Clima , Ecossistema , Invertebrados/fisiologia , Alga Marinha/fisiologia , Tasmânia , UrbanizaçãoRESUMO
Using the USEPA methodology we estimated the probabilistic chronic risks for calves and adult cows due to pesticide exposure through oral intake of contaminated surface and ground waters in Tres Arroyos County (Argentina). Because published data on pesticide toxicity endpoints for cows are scarce, we used threshold levels based on interspecies extrapolation methods. The studied waters showed acceptable quality for cattle production since none of the pesticides were present at high-enough concentrations to potentially affect cow health. Moreover, ground waters had better quality than surface waters, with dieldrin and deltamethrin being the pesticides associated with the highest risk values in the former and the latter water compartments, respectively. Our study presents a novel use of the USEPA risk methodology proving it is useful for water quality evaluation in terms of pesticide toxicity for cattle production. This approach represents an alternative tool for water quality management in the absence of specific cattle pesticide regulatory limits.
Assuntos
Água Potável/química , Água Subterrânea/química , Praguicidas/toxicidade , Medição de Risco , Qualidade da Água/normas , Animais , Argentina , Bovinos , Monitoramento Ambiental , Feminino , Praguicidas/análise , Poluentes Químicos da Água/análise , Poluição da Água/efeitos adversosRESUMO
The viability of spermatozoa is a crucial parameter to evaluate their quality that is an important issue in ecotoxicological studies. Here, a new method has been developed to rapidly determine the viability of spermatozoa in three marine invertebrates: the ascidian Ciona intestinalis, the sea urchin Paracentrotus lividus and the mollusc Mytilus galloprovincialis. This method employed the dual DNA fluorescent staining coupled with spectrofluorimetric analysis. The dual fluorescent staining used the SYBR-14 stained live spermatozoa and propidium iodide stained degenerated cells that had lost membrane integrity. Stain uptake was assessed by confocal microscopy and then the percentage of live and dead spermatozoa was quantified by spectrofluorimetric analysis. The microscopic examination revealed three populations of spermatozoa: living-SYBR-14 stained, dead-PI stained, and dying-doubly stained spermatozoa. The fluorescence emission peak values recorded in a spectrofluorimeter provide the portion of live and dead spermatozoa showing a significant negative correlation. The stain combination was further validated using known ratios of live and dead spermatozoa. The present study demonstrated that the dual DNA staining with SYBR-14 and propidium iodide was effective in assessing viability of spermatozoa in marine invertebrates and that spectrofluorimetric analysis can be successfully employed to evaluate the percentage of live and dead spermatozoa. The method develop herein is simple, accurate, rapid, sensitive, and cost-effective, so it could be a useful tool by which marine pollutants may be screened for spermiotoxicity.
Assuntos
Organismos Aquáticos/citologia , Monitoramento Ambiental/métodos , Corantes Fluorescentes/química , Invertebrados/citologia , Espectrometria de Fluorescência/métodos , Espermatozoides/efeitos dos fármacos , Poluição da Água/efeitos adversos , Animais , Organismos Aquáticos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Invertebrados/efeitos dos fármacos , Masculino , Microscopia Confocal , Compostos Orgânicos/química , Propídio/química , Especificidade da Espécie , Espermatozoides/citologia , Coloração e RotulagemRESUMO
In this case, a physician rejects a patient's concerns that tainted water is harming the patient and her community. Stereotypes and biases regarding socioeconomic class and race/ethnicity, constraining diagnostic frameworks, and fixed first impressions could skew the physician's judgment. This paper narratively illustrates how cultivating humility could help the physician truly hear the patient's suggestions. The discussion builds on the multifaceted concept of cultural humility as a lifelong journey that addresses not only stereotypes and biases but also power inequalities and community inequities. Insurgent multiculturalism is a complementary concept. Through epistemic humility-which includes both intellectual and emotional components-and admitting uncertainty, physicians can enhance patients' and families' epistemic authority and health agency.
Assuntos
Tomada de Decisão Clínica , Diversidade Cultural , Conhecimento , Relações Médico-Paciente , Médicos , Saúde Pública , Poluição da Água/efeitos adversos , Humanos , Julgamento , Participação do Paciente , Poder Psicológico , Fatores Socioeconômicos , Estereotipagem , Incerteza , ÁguaRESUMO
The Department of Veterans Affairs (VA) adopts as final an interim final rule addressing payment or reimbursement of certain medical expenses for family members of Camp Lejeune veterans. Under this rule, VA reimburses family members, or pays providers, for medical expenses incurred as a result of certain illnesses and conditions that may be associated with contaminants present in the base water supply at U.S. Marine Corps Base Camp Lejeune (Camp Lejeune), North Carolina, from August 1, 1953, to December 31, 1987. Payment or reimbursement is made within the limitations set forth in statute and Camp Lejeune family members receive hospital care and medical services that are consistent with the manner in which we provide hospital care and medical services to Camp Lejeune veterans. The statutory authority has since been amended to also include certain veterans' family members who resided at Camp Lejeune, North Carolina, for no less than 30 days (consecutive or nonconsecutive) between August 1, 1953, and December 31, 1987. This final rule will reflect that statutory change and will address public comments received in response to the interim final rule.
Assuntos
Compensação e Reparação/legislação & jurisprudência , Gastos em Saúde/legislação & jurisprudência , Militares/legislação & jurisprudência , Veteranos/legislação & jurisprudência , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Família , Humanos , Instalações Militares , North Carolina , Estados Unidos , Poluição da Água/efeitos adversos , Abastecimento de ÁguaRESUMO
Coastal hypoxia (dissolved oxygen ≤ 2 mg/L) is a growing problem worldwide that threatens marine ecosystem services, but little is known about economic effects on fisheries. Here, we provide evidence that hypoxia causes economic impacts on a major fishery. Ecological studies of hypoxia and marine fauna suggest multiple mechanisms through which hypoxia can skew a population's size distribution toward smaller individuals. These mechanisms produce sharp predictions about changes in seafood markets. Hypoxia is hypothesized to decrease the quantity of large shrimp relative to small shrimp and increase the price of large shrimp relative to small shrimp. We test these hypotheses using time series of size-based prices. Naive quantity-based models using treatment/control comparisons in hypoxic and nonhypoxic areas produce null results, but we find strong evidence of the hypothesized effects in the relative prices: Hypoxia increases the relative price of large shrimp compared with small shrimp. The effects of fuel prices provide supporting evidence. Empirical models of fishing effort and bioeconomic simulations explain why quantifying effects of hypoxia on fisheries using quantity data has been inconclusive. Specifically, spatial-dynamic feedbacks across the natural system (the fish stock) and human system (the mobile fishing fleet) confound "treated" and "control" areas. Consequently, analyses of price data, which rely on a market counterfactual, are able to reveal effects of the ecological disturbance that are obscured in quantity data. Our results are an important step toward quantifying the economic value of reduced upstream nutrient loading in the Mississippi Basin and are broadly applicable to other coupled human-natural systems.
Assuntos
Comércio/tendências , Ecossistema , Pesqueiros/economia , Penaeidae/fisiologia , Alimentos Marinhos/economia , Poluição da Água/efeitos adversos , Poluição da Água/economia , Animais , Tamanho Corporal , Comércio/estatística & dados numéricos , Conservação dos Recursos Naturais , Fertilizantes/efeitos adversos , Golfo do México , Atividades Humanas/economia , Oxigênio/análise , Estações do Ano , Água do Mar/química , Poluentes Químicos da Água/efeitos adversosRESUMO
The Department of Veterans Affairs (VA) amends its adjudication regulations regarding presumptive service connection, adding certain diseases associated with contaminants present in the base water supply at U.S. Marine Corps Base Camp Lejeune (Camp Lejeune), North Carolina, from August 1, 1953, to December 31, 1987. This final rule establishes that veterans, former reservists, and former National Guard members, who served at Camp Lejeune for no less than 30 days (consecutive or nonconsecutive) during this period, and who have been diagnosed with any of eight associated diseases, are presumed to have incurred or aggravated the disease in service for purposes of entitlement to VA benefits. In addition, this final rule establishes a presumption that these individuals were disabled during the relevant period of service for purposes of establishing active military service for benefits purposes. Under this presumption, affected former reservists and National Guard members have veteran status for purposes of entitlement to some VA benefits. This amendment implements a decision by the Secretary of Veterans Affairs that service connection on a presumptive basis is warranted for claimants who served at Camp Lejeune during the relevant period and for the requisite amount of time and later develop certain diseases.
Assuntos
Avaliação da Deficiência , Definição da Elegibilidade/legislação & jurisprudência , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Militares/legislação & jurisprudência , Ajuda a Veteranos de Guerra com Deficiência/legislação & jurisprudência , Saúde dos Veteranos/legislação & jurisprudência , Veteranos/legislação & jurisprudência , Poluentes da Água/efeitos adversos , Poluição da Água/efeitos adversos , Humanos , Neoplasias Renais/etiologia , Leucemia/etiologia , Instalações Militares , Doenças do Sistema Nervoso/etiologia , North Carolina , Doença de Parkinson/etiologia , Estados Unidos , Compostos Orgânicos Voláteis/efeitos adversos , Abastecimento de ÁguaRESUMO
A multi-disciplinary approach was used to evaluate the health of yellow perch (Perca flavescens) in the St. Lawrence River (Quebec, Canada), which is experiencing a severe population decline in the downstream portion of the river. Physiological parameters, liver alterations, trace metal concentrations, parasite prevalence and abundance, stable isotope composition, and the presence/absence of the viral hemorragic septicemia virus (VHSV) were evaluated in perch collected at six sites along the river: Lake St. François, Lake St. Louis (north and south), Beauregard Island, and Lake St. Pierre (north and south). Trace metal concentrations in surface water were higher in Lake St. Louis and downstream of a major urban wastewater treatment plant discharge, indicating that this effluent was a significant source of Cu, As, Ag, Zn, and Cd. Levels of Pb in surface water exceeded thresholds for the protection of aquatic life in Lake St. Louis and were negatively correlated with body condition index in this lake. In Lake St. Pierre, Cu, Ag, and Cd bioaccumulated significantly in perch liver and lower body condition index and greater liver damage were observed compared to upstream sites. Parasite analyses indicated a higher abundance of metacercariae of the trematodes Apophallus brevis and Diplostomum spp. in Lake St. Louis, and VHSV was not detected in the liver of yellow perch for all studied sites. Overall, results suggested that the global health of yellow perch from Lake St. Pierre is lower compared to upstream studied sites, which could contribute to the documented population collapse at this site.
Assuntos
Fígado/efeitos dos fármacos , Metais Pesados/toxicidade , Percas/fisiologia , Poluentes Químicos da Água/toxicidade , Poluição da Água/efeitos adversos , Animais , Isótopos de Carbono/análise , Monitoramento Ambiental , Feminino , Lagos/química , Fígado/química , Fígado/patologia , Masculino , Metais Pesados/análise , Músculos/química , Isótopos de Nitrogênio/análise , Novirhabdovirus/isolamento & purificação , Percas/parasitologia , Percas/virologia , Quebeque , Rios/química , Águas ResiduáriasRESUMO
Human demands on marine resources and space are currently unprecedented and concerns are rising over observed declines in marine biodiversity. A quantitative understanding of the impact of industrial activities on the marine environment is thus essential. Life cycle assessment (LCA) is a widely applied method for quantifying the environmental impact of products and processes. LCA was originally developed to assess the impacts of land-based industries on mainly terrestrial and freshwater ecosystems. As such, impact indicators for major drivers of marine biodiversity loss are currently lacking. We review quantitative approaches for cause-effect assessment of seven major drivers of marine biodiversity loss: climate change, ocean acidification, eutrophication-induced hypoxia, seabed damage, overexploitation of biotic resources, invasive species and marine plastic debris. Our review shows that impact indicators can be developed for all identified drivers, albeit at different levels of coverage of cause-effect pathways and variable levels of uncertainty and spatial coverage. Modeling approaches to predict the spatial distribution and intensity of human-driven interventions in the marine environment are relatively well-established and can be employed to develop spatially-explicit LCA fate factors. Modeling approaches to quantify the effects of these interventions on marine biodiversity are less well-developed. We highlight specific research challenges to facilitate a coherent incorporation of marine biodiversity loss in LCA, thereby making LCA a more comprehensive and robust environmental impact assessment tool. Research challenges of particular importance include i) incorporation of the non-linear behavior of global circulation models (GCMs) within an LCA framework and ii) improving spatial differentiation, especially the representation of coastal regions in GCMs and ocean-carbon cycle models.
Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Mudança Climática , Ecossistema , Estágios do Ciclo de Vida , Modelos Teóricos , Adaptação Biológica , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/fisiologia , Biodiversidade , Humanos , Poluição da Água/efeitos adversos , Poluição da Água/análiseRESUMO
Hydrotechnical facilities have significant environmental and health imyacts. Results of a hygienic assessment of the condition of environmental objects in the area of the yrojected Nizhny Novgorod low-head water ylant develoyment showed that the both air and water pollution level in decentralized water supply sources in Balakhna and Gorodets are lower than in the city of Nizhny Novgorod, and those of the water in the water supply network are higher than in the reference area. A cross-sectional study has revealed in the main grouf (Gorodets, Zavolzhye and Balakhna) the rate of morbidity of nervous system and cardiovascular diseases to be higher than in the reference group (Nizhny Novgorod), with cardiovascular diseases being the largest contributor to the overall grevalence rate in the groug under analysis; and digestive system diseases, in the reference group. The study has no revealed direct correlation between morbidity rate in children and adults and the studied factors. However, a direct relationship has been found between the prevalence rate of endocrine diseases in children and the quality of water in the water supply network in Balakhna District (p<0.007); also, there's a correlation between the morbidity rate of digestive diseases and air pollution and water quality in the water supply network (p<0.009). In the Gorodets District, the same situation has been revealed: the morbidity rate of endocrine diseases in children depends on quality of water from the water supply network (p<0.049); the prevalence rate of digestive diseases, on air pollution and water quality in the water supply network (p<0.048). In the same region in adults the prevalence rate of the nervous system diseases, digestive diseases and diseases of the skin and subcutaneous tissue depends on air pollution and pollution of water in the water supply network (p<0.011, p<0.01 and p<0.02, respectively).
Assuntos
Poluição do Ar , Doença Ambiental , Poluição da Água , Abastecimento de Água , Adulto , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Criança , Estudos Transversais , Doença Ambiental/classificação , Doença Ambiental/epidemiologia , Doença Ambiental/etiologia , Monitoramento Ambiental/normas , Monitoramento Ambiental/estatística & dados numéricos , Nível de Saúde , Humanos , Desenvolvimento Industrial , Prevalência , Saúde Pública/normas , Saúde Pública/estatística & dados numéricos , Federação Russa/epidemiologia , Poluição da Água/efeitos adversos , Poluição da Água/análise , Qualidade da Água/normas , Abastecimento de Água/métodos , Abastecimento de Água/normasRESUMO
There are presented results of the cytome analysis of epithelium of buccal mucosa in 167 children aged of 5-7 years, permanently residing in the city of Magnitogorsk and visiting municipal kindergartens. Frequencies of the main indices of genotoxic and toxic effects were: cells with micronuclei - 0.29±0.04 %, with protrusions ofnuclei - 1.47±0.17 %, with double nuclei -1.96±0.13 %, with two nuclei - 3,28±0,16 %, with perinuclear vacuole - 9.66±0.86 %, with pycnosis of nucleus - 4.60±0.31 per 1000 cells, with karyorrhexis - 0.86±0.15per 1000 cells, with lysis of nucleus - 54.34±3.90 per 1000 cells, the condensed chromatin cells - 10.59±1.35 per 1000 cells. Most of these indices didn't differ from the same detected earlier in buccal epithelial cells from children of the same age in Moscow, except cells with perinuclear vacuole, which frequency in Moscow cohort was twice higher. Frequencies of cells with these anomalies were associated with the content of 19 out of 326 revealed components of contamination of the total-winter snow samples, taken on the territories of the kindergartens, which were visited by examined children. There was shown lack of differences from basic values of main indices previously establishedfor the children of the same age in Moscow, with the exception of cells with perinuclear vacuole, the rate of which in Moscow was twice higher. There were revealed confounding factors associated with test indices: gender of the child, the annual number of acute respiratory diseases, health group, income per one person in family, alcohol intake by parents.
Assuntos
Exposição Ambiental , Testes para Micronúcleos , Mucosa Bucal/patologia , Poluição da Água , Criança , Pré-Escolar , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Disparidades nos Níveis de Saúde , Humanos , Masculino , Testes para Micronúcleos/métodos , Testes para Micronúcleos/estatística & dados numéricos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Federação Russa/epidemiologia , Neve , Poluição da Água/efeitos adversos , Poluição da Água/análiseRESUMO
Directive 2000/60/EC and subsequent legislation provide a list of priority substances to be measured and monitored in EU water bodies and require the adoption of analytical methods that ensure comparability of the data collected in all Member States. These regulations and standards have gradually improved water quality in the EU. However, new drugs, whose effects on ecosystems and health are still to be determined, are detected with growing frequency. The Member States are now called upon to characterize and monitor these pollutants in view of their possible inclusion in the priority substance list.
Assuntos
Concentração Máxima Permitida , Poluentes Químicos da Água/análise , Poluição da Água/legislação & jurisprudência , Qualidade da Água/normas , Animais , Animais Selvagens , Resíduos de Drogas/efeitos adversos , Resíduos de Drogas/análise , Disruptores Endócrinos/análise , União Europeia , Humanos , Metais Pesados/efeitos adversos , Metais Pesados/análise , Compostos Orgânicos/efeitos adversos , Compostos Orgânicos/análise , Resíduos de Praguicidas/efeitos adversos , Resíduos de Praguicidas/análise , Rios , Águas Residuárias/química , Poluentes Químicos da Água/efeitos adversos , Poluição da Água/efeitos adversos , Poluição da Água/prevenção & controleRESUMO
We assessed the ability of an artificial clay (Ca-aminoclay) to suppress harmful algal bloom species (HABs) such as Cochlodinium polykrikoides and Chattonella marina and investigated the ecological responses in the closed and open microcosm systems. The Ca-aminoclay induced rapidly and selectively cell lysis in the HABs. However, applying Ca-aminoclay could cause adverse impacts in terms of biological and environmental changes. The bacterioplankton abundance increased and then, the abundances of heterotrophic nanoflagellates and ciliates increased rapidly. Extremely poor environmental conditions such as increase in nutrients and development of anoxic conditions were sustained continuously in a closed system, while the environmental conditions in open systems deteriorated before recovering to the initial conditions. We evaluated the potential for the occurrence of a bloom of another phytoplankton after HABs had been controlled using the Ca-aminoclay. The Ca-aminoclay controlled blooms of Chattonella marina in mixed cell cultures containing a Tetraselmis chui. However, T. chui increased over time and then bloomed. Therefore, caution should be taken when considering the direct application of Ca-aminoclay in natural environments even though it offers the rapid removal of HABs.
Assuntos
Silicatos de Alumínio/toxicidade , Ecossistema , Proliferação Nociva de Algas/efeitos dos fármacos , Praguicidas/toxicidade , Cálcio/química , Argila , Plâncton/química , Microbiologia da Água , Poluição da Água/efeitos adversosRESUMO
A weight of evidence (WoE) framework has been applied to assess sediment quality of a typical freshwater lake, Tai Lake in China, where the sediments were contaminated by various chemicals but showed no acute lethality to the benthic invertebrate, Chironomus dilutus. A quantitative scoring method was employed to integrate three lines of evidence (LoE), including adverse effects in life cycle bioassays, biomarker responses, and bioavailability-based chemical analysis. Six biomarkers were determined in C. dilutus after the exposure to the sediments from Tai Lake and provided sensitive indication of sublethal effects at the molecular level. The biomarkers included cytochrome P450, glutathione S-transferase, carboxylesterase, acetylcholinesterase, catalase, and lipid peroxidation. The changes of the biomarkers were summarized for individual sampling sites by computing the integrated biomarker response (IBR) indices. Complementary information was also confirmed by the interrelationship of the LoEs. The IBR indices gained before pupation correlated well with the impairments of emergence of the midges, and altered acetylcholinesterase was corroborated by the detection of chlorpyrifos, an organophosphate pesticide. The relationship between bioavailable toxic units estimated by Tenax extractable concentrations of chemicals in sediment and the observed toxicity in the midges helped to identify the putative toxicity contributors to C. dilutus. Overall, the WoE method clearly distinguished the contaminated sites and ranked them by the level of contamination. Sediment-associated pesticides, particularly γ-hexachlorocyclohexane and chlorpyrifos, were the possible contributors to chronic toxicity to the midges.