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1.
Ecol Evol ; 14(8): e11691, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39114178

RESUMO

Understanding interactions within and between species is crucial to ecological research. However, for cetaceans such interactions can be difficult to observe in the field. Photographs offer an opportunity to study intra- and inter-specific interactions, by capturing 'snapshots' of their occurrence over space and time. At-surface and underwater photographs of bottlenose dolphins (Tursiops aduncus) inhabiting Ponta do Ouro Partial Marine Reserve (PPMR), Mozambique, were used to examine evidence of interactions with other dolphins, predators and ectoparasites. Intra-specific scarring levels significantly differed by sex and age class, with males displaying more scarring than females. Similarly, adults had more scarring than juveniles or calves. Shark bites significantly differed in their distribution across dolphin body areas, with the dorsal side being more frequently wounded than the ventral side. The presence of barnacles was exclusive to fluke, dorsal and pectoral fins, and showed strong seasonal trends. Overall, this study demonstrates the value of photographs for examining marine ecological interactions. It provides the first insights regarding dolphin social behaviour, predation risk and health for this population. These in turn will support future research into the population dynamics and conservation of the PPMR dolphins, which is urgently required in the face of locally increasing anthropogenic pressures.

3.
Ann Surg Oncol ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909113

RESUMO

BACKGROUND: Few studies have examined the performance of artificial intelligence (AI) content detection in scientific writing. This study evaluates the performance of publicly available AI content detectors when applied to both human-written and AI-generated scientific articles. METHODS: Articles published in Annals of Surgical Oncology (ASO) during the year 2022, as well as AI-generated articles using OpenAI's ChatGPT, were analyzed by three AI content detectors to assess the probability of AI-generated content. Full manuscripts and their individual sections were evaluated. Group comparisons and trend analyses were conducted by using ANOVA and linear regression. Classification performance was determined using area under the curve (AUC). RESULTS: A total of 449 original articles met inclusion criteria and were evaluated to determine the likelihood of being generated by AI. Each detector also evaluated 47 AI-generated articles by using titles from ASO articles. Human-written articles had an average probability of being AI-generated of 9.4% with significant differences between the detectors. Only two (0.4%) human-written manuscripts were detected as having a 0% probability of being AI-generated by all three detectors. Completely AI-generated articles were evaluated to have a higher average probability of being AI-generated (43.5%) with a range from 12.0 to 99.9%. CONCLUSIONS: This study demonstrates differences in the performance of various AI content detectors with the potential to label human-written articles as AI-generated. Any effort toward implementing AI detectors must include a strategy for continuous evaluation and validation as AI models and detectors rapidly evolve.

5.
Integr Environ Assess Manag ; 20(2): 454-464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37527952

RESUMO

The pesticide registration process in North America, including the USA and Canada, involves conducting a risk assessment based on relatively conservative modeling to predict pesticide concentrations in receiving waterbodies. The modeling framework does not consider some commonly adopted best management practices that can reduce the amount of pesticide that may reach a waterbody, such as vegetative filter strips (VFS). Currently, VFS are being used by growers as an effective way to reduce off-site movement of pesticides, and they are being required or recommended on pesticide labels as a mitigation measure. Given the regulatory need, a pair of multistakeholder workshops were held in Raleigh, North Carolina, to discuss how to incorporate VFS into pesticide risk assessment and risk management procedures within the North American regulatory framework. Because the risk assessment process depends heavily on modeling, one key question was how to quantitatively incorporate VFS into the existing modeling approach. Key outcomes from the workshops include the following: VFS have proven effective in reducing pesticide runoff to surface waterbodies when properly located, designed, implemented, and maintained; Vegetative Filter Strip Modeling System (VFSMOD), a science-based and widely validated mechanistic model, is suitable for further vetting as a quantitative simulation approach to pesticide mitigation with VFS in current regulatory settings; and VFSMOD parametrization rules need to be developed for the North American aquatic exposure assessment. Integr Environ Assess Manag 2024;20:454-464. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Praguicidas , Praguicidas/toxicidade , Praguicidas/análise , Medição de Risco , Gestão de Riscos , América do Norte , Canadá
7.
Environ Pollut ; 334: 122154, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37419207

RESUMO

Air pollutants from poultry production, such as ammonia (NH3) and particulate matter (PM), have raised concerns due to their potential negative impacts on human health and the environment. Vegetative environmental buffers (VEBs), consisting of trees and/or grasses planted around poultry houses, have been investigated as a mitigation strategy for these emissions. Although previous research demonstrated that VEBs can reduce NH3 and PM emissions, these studies used a limited number of samplers and did not examine concentration profiles. Moreover, the differences between daytime and nighttime emissions have not been investigated. In this study, we characterized emission profiles from a commercial poultry house using an array with multiple sampling heights and explored the differences between daytime and nighttime NH3 and PM profiles. We conducted three sampling campaigns, each with ten sampling events (five daytime and five nighttime), at a VEB-equipped poultry production facility. NH3 and PM samples were collected downwind from the ventilation tunnel fans before, within, and after the VEB. Results showed that ground-level concentrations beyond the VEB decreased to 8.0% ± 2.7% for NH3, 13% ± 4% for TSP, 13% ± 4% for PM10, and 2.4% ± 2.8% for PM2.5 of the original concentrations from the exhaust tunnel fan, with greater reduction efficiency during daytime than nighttime. Furthermore, pollutant concentrations were positively intercorrelated. These findings will be valuable for developing more effective pollutant remediation strategies in poultry house emissions.


Assuntos
Poluentes Atmosféricos , Material Particulado , Animais , Humanos , Material Particulado/análise , Aves Domésticas , Poluentes Atmosféricos/análise , Emissões de Veículos , Plantas , Amônia/análise , Monitoramento Ambiental/métodos
9.
Integr Environ Assess Manag ; 15(5): 714-725, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31144769

RESUMO

Pesticide regulation requires regulatory authorities to assess the potential ecological risk of pesticides submitted for registration, and most risk assessment schemes use a tiered testing and assessment approach. Standardized ecotoxicity tests, environmental fate studies, and exposure models are used at lower tiers and follow well-defined methods for assessing risk. If a lower tier assessment indicates that the pesticide may pose an ecological risk, higher tier studies using more environmentally realistic conditions or assumptions can be performed to refine the risk assessment and inform risk management options. However, there is limited guidance in the United States on options to refine an assessment and how the data will be incorporated into the risk assessment and risk management processes. To overcome challenges to incorporation of higher tier data into ecological risk assessments and risk management of pesticides, a workshop was held in Raleigh, North Carolina. Attendees included representatives from the United States Environmental Protection Agency, United States Department of Agriculture, National Oceanic and Atmospheric Administration, universities, commodity groups, consultants, nonprofit organizations, and the crop protection industry. Key recommendations emphasized the need for 1) more effective, timely, open communication among registrants, risk assessors, and risk managers earlier in the registration process to identify specific protection goals, address areas of potential concern where higher tier studies or assessments may be required, and if a higher tier study is necessary that there is agreement on study design; 2) minimizing the complexity of study designs while retaining high value to the risk assessment and risk management process; 3) greater transparency regarding critical factors utilized in risk management decisions with clearly defined protection goals that are operational; and 4) retrospective analyses of success-failure learnings on the acceptability of higher tier studies to help inform registrants on how to improve the application of such studies to risk assessments and the risk management process. Integr Environ Assess Manag 2019;15:714-725. © 2019 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Agricultura/legislação & jurisprudência , Regulamentação Governamental , Guias como Assunto , Praguicidas/toxicidade , Gestão de Riscos/normas , Medição de Risco/normas , Estados Unidos
10.
J Agric Food Chem ; 66(31): 8231-8236, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-29957951

RESUMO

Ground-level ozone is formed when volatile organic compounds (VOCs) react with hydroxyl radicals and nitrogen oxides in the presence of ultraviolet light. Research has typically focused on the release and control of VOCs from hydrocarbon processing; however, agricultural activities, such as poultry production, can also be VOC sources and potentially contribute to ozone pollution. Therefore, this study examines the emission of C2-C6 VOCs from poultry houses and the use of a vegetative environmental buffer (VEB) as a potential mitigation strategy. Sampling campaigns were conducted at two farms, one with and one without a VEB. Of the nine compounds measured, methanol, ethanol, and acetone were the primary VOCs emitted and had the largest ozone-formation potential (OFP). A significantly larger decrease in the OFP for methanol as a function of distance from the poultry house was observed at the farm with the VEB as compared with at the farm without the VEB. These results suggest that besides being a visual barrier and particulate screen, VEBs can provide some control of VOCs emitted from poultry production.


Assuntos
Agricultura/métodos , Poluição do Ar/prevenção & controle , Abrigo para Animais , Plantas/metabolismo , Aves Domésticas/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Animais , Óxidos de Nitrogênio/química , Ozônio/análise , Ozônio/química , Raios Ultravioleta , Compostos Orgânicos Voláteis/química
11.
Environ Pollut ; 238: 10-16, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29529478

RESUMO

Poultry-emitted air pollutants, including particulate matter (PM) and ammonia, have raised concerns due to potential negative effects on human health and the environment. However, developing and optimizing remediation technologies requires a better understanding of air pollutant concentrations, the emission plumes, and the relationships between the pollutants. Therefore, we conducted ten field experiments to characterize PM (total suspended particulate [TSP], particulate matter less than 10 µm in aerodynamic diameter [PM10], and particulate matter less than 2.5 µm in aerodynamic diameter [PM2.5]) and ammonia emission-concentration profiles from a typical commercial poultry house. The emission factors of the poultry house, which were calculated using the concentrations and fan speed, were 0.66 (0.29-0.99) g NH3-N bird-1d-1 for ammonia, 52 (44-168) g d-1AU-1 (AU = animal unit = 500 kg) for TSP, 3.48 (1.16-9.03) g d-1AU-1 for PM10, and 0.07 (0.00-0.36) g d-1AU-1 for PM2.5. PM and ammonia emission concentrations decreased as distance from the fan increased. Although emission concentrations were similar in the daytime and nighttime, diurnal and nocturnal plume shapes were different due to the increased stability of the atmosphere at night. Particle size distribution analysis revealed that, at a given height, the percentage of PM10 and PM2.5 was consistent throughout the plume, indicating that the larger particles were not settling out of the airstream faster than the smaller particles. Overall, the direction of the measured air pollutant emission plumes was dominated by the tunnel fan ventilation airflow rate and direction instead of the ambient wind speed and direction. This is important because currently-available air dispersion models use ambient or modeled wind speed and direction as input parameters. Thus, results will be useful in evaluating dispersion models for ground-level, horizontally-released, point sources and in developing effective pollutant remediation strategies for emissions.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Monitoramento Ambiental/métodos , Abrigo para Animais , Material Particulado/análise , Poluição do Ar/análise , Animais , Humanos , Tamanho da Partícula , Aves Domésticas
12.
Environ Sci Pollut Res Int ; 25(9): 8735-8746, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29327189

RESUMO

Trichloroethylene (TCE) is a highly effective industrial degreasing agent and known carcinogen. It was frequently buried improperly in landfills and has subsequently become one of the most common groundwater and soil contaminants in the USA. A common strategy to remediate TCE-contaminated sites and to prevent movement of the TCE plumes into waterways is to construct biowalls which consist of biomaterials and amendments to enhance biodegradation. This approach was chosen to contain a TCE plume emanating from a closed landfill in Maryland. However, predicting the effectiveness of biowalls is often site specific. Therefore, we conducted an extensive series of batch reactor studies at 12 °C as opposed to the typical room temperature to examine biowall fill-material combinations including the effects of zero-valent iron (ZVI) and glycerol amendments. No detectable TCE was observed after several months in the laboratory study when using the unamended 4:3 mulch-to-compost combination. In the constructed biowall, this mixture reduced the upstream TCE concentration by approximately 90% and generated ethylene downstream, an indication of successful reductive dechlorination. However, the more toxic degradation product vinyl chloride (VC) was also detected downstream at levels approximately ten times greater than the maximum contaminant level. This indicates that incomplete degradation also occurred. In the laboratory, ZVI reduced VC formation. A hazard quotient was calculated for the landfill site with and without the biowall. The addition of the biowall decreased the hazard quotient by 88%.


Assuntos
Reatores Biológicos , Água Subterrânea/química , Folhas de Planta/química , Tricloroetileno/análise , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Adsorção , Biodegradação Ambiental , Glicerol/química , Ferro/química , Cloreto de Vinil/análise
13.
Chemosphere ; 186: 151-159, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28772182

RESUMO

Electronic noses have been widely used in the food industry to monitor process performance and quality control, but use in wastewater and biosolids treatment has not been fully explored. Therefore, we examined the feasibility of an electronic nose to discriminate between treatment conditions of alkaline stabilized biosolids and compared its performance with quantitative analysis of key odorants. Seven lime treatments (0-30% w/w) were prepared and the resultant off-gas was monitored by GC-MS and by an electronic nose equipped with ten metal oxide sensors. A pattern recognition model was created using linear discriminant analysis (LDA) and principal component analysis (PCA) of the electronic nose data. In general, LDA performed better than PCA. LDA showed clear discrimination when single tests were evaluated, but when the full data set was included, discrimination between treatments was reduced. Frequency of accurate recognition was tested by three algorithms with Euclidan and Mahalanobis performing at 81% accuracy and discriminant function analysis at 70%. Concentrations of target compounds by GC-MS were in agreement with those reported in literature and helped to elucidate the behavior of the pattern recognition via comparison of individual sensor responses to different biosolids treatment conditions. Results indicated that the electronic nose can discriminate between lime percentages, thus providing the opportunity to create classes of under-dosed and over-dosed relative to regulatory requirements. Full scale application will require careful evaluation to maintain accuracy under variable process and environmental conditions.


Assuntos
Poluentes Atmosféricos/análise , Nariz Eletrônico , Monitoramento Ambiental/métodos , Odorantes/análise , Eliminação de Resíduos Líquidos , Compostos de Cálcio , Análise Discriminante , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óxidos , Análise de Componente Principal
14.
Environ Pollut ; 222: 412-422, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28104345

RESUMO

Polybrominated diphenyl ethers (PBDEs) may enter the environment because of accumulation in biosolids followed by application to agricultural lands. No published dissipation studies are available for PBDEs in agricultural soils after biosolids application. Therefore, we conducted a 3-year study to examine the fate of PBDEs in a small-scale 0.24-ha continuously cropped field after a single biosolids application at 72.3 wet tons/ha and determined dissipation half-lives for BDE-47+BDE-99 and BDE-209. In addition, we conducted a large-scale survey of soils from 26 mostly pasture fields at 10 farms with detailed information on timing and rate of biosolids applications. In the small-scale experiment, maximum soil PBDE concentrations of 43.7 ± 42.7 µg kg-1 d.w. for BDE-209 and 6.05 ± 7.15 µg kg-1 d.w. for BDE-47+BDE-99 were reached 1 year after application. We hypothesized that PBDEs were slowly released from the biosolids matrix into the soil over the first year. After 3 years, median BDE-47+BDE-99 concentrations were approximately equal to preapplication levels, whereas median BDE-209 concentrations remained ∼129% above preapplication levels. The estimated residence time from the small-scale experiment was 342 d for BDE-47+BDE-99 and 861 d for BDE-209. In the large-scale study, a subset of fields that received a single biosolids application was used to generate another estimate of residence time: 704 d for BDE-47+BDE-99 and 1440 d for BDE-209. These longer residence time estimates were used in three different first-order decay dissipation scenarios (continuous, limited, and no dissipation) to predict PBDE concentration in fields with single and multiple biosolids applications. Results indicate that dissipation occurs primarily in the first 2 years after application, but residues remaining in the soil after this period are likely to be much more tightly bound and less available for degradation.


Assuntos
Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Esgotos/química , Poluentes do Solo/análise , Solo/química , Fatores de Tempo
15.
J Agric Food Chem ; 64(1): 6-12, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25671793

RESUMO

Rising concentrations of atmospheric carbon dioxide ([CO2]) and subsequent changes in climate, including temperature and precipitation extremes, are very likely to alter pest pressures in both managed and unmanaged plant communities. Such changes in pest pressures can be positive (migration from a region) or negative (new introductions), but are likely to be accompanied by significant economic and environmental consequences. Recent studies indicate the range of invasive weeds such as kudzu and insects such as mountain pine beetle have already expanded to more northern regions as temperatures have risen. To reduce these consequences, a better understanding of the link between CO2/climate and pest biology is needed in the context of existing and new strategies for pest management. This paper provides an overview of the probable biological links and the vulnerabilities of existing pest management (especially chemical control) and provides a preliminary synthesis of research needs that could potentially improve the ability to monitor, mitigate, and manage pest impacts.


Assuntos
Dióxido de Carbono/análise , Insetos/crescimento & desenvolvimento , Controle de Pragas , Plantas Daninhas/crescimento & desenvolvimento , Controle de Plantas Daninhas , Animais , Mudança Climática , Ecossistema , Controle de Pragas/economia , Controle de Plantas Daninhas/economia
16.
J Agric Food Chem ; 64(1): 4-5, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26709728

RESUMO

This introductory paper provides an overview of Perspectives papers written by plenary speakers from the 13th IUPAC International Congress of Pesticide Chemistry held in San Francisco, CA, USA, in August 2014. This group of papers emphasizes some of the emerging issues and challenges at the forefront of agricultural research: sustainability; agriculture's response to climate change and population growth; pollinator health and risk assessment; and global food production and food security. In addition, as part of the Congress, a workshop on "Developing Global Leaders for Research, Regulation, and Stewardship of Crop Protection Chemistry in the 21st Century" identified specific recommendations to attract the best scientists to agricultural science, to provide opportunities to study and conduct research on crop protection chemistry topics, and to improve science communication skills.


Assuntos
Produtos Agrícolas/química , Praguicidas/análise , Agricultura , Mudança Climática , Humanos
17.
Environ Pollut ; 210: 182-91, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26716732

RESUMO

Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18-39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.


Assuntos
Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos Clorados/química , Resíduos de Praguicidas/química , Praguicidas/química , Poluentes do Solo/química , Agricultura , Animais , Disponibilidade Biológica , DDT/análise , DDT/farmacocinética , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/química , Diclorodifenil Dicloroetileno/farmacocinética , Dieldrin/análise , Dieldrin/química , Dieldrin/farmacocinética , Ecossistema , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/farmacocinética , Oligoquetos/metabolismo , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Praguicidas/análise , Praguicidas/farmacocinética , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética
18.
Environ Toxicol Chem ; 35(2): 311-21, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26467536

RESUMO

Limited data are available on the fate of clothianidin under realistic agricultural production conditions. The present study is the first large-scale assessment of clothianidin residues in soil and bee-relevant matrices from corn and canola fields after multiple years of seed-treatment use. The average soil concentration from 50 Midwest US corn fields with 2 yr to 11 yr of planting clothianidin-treated seeds was 7.0 ng/g, similar to predicted concentrations from a single planting of Poncho 250-treated corn seeds (6.3 ng/g). The water-extractable (i.e., plant-bioavailable) clothianidin residues in soil were only 10% of total residues. Clothianidin concentrations in soil reached a plateau concentration (amount applied equals amount dissipated) in fields with 4 or more application years. Concentrations in corn pollen from these fields were low (mean: 1.8 ng/g) with no correlation to total years of use or soil concentrations. For canola, soil concentrations from 27 Canadian fields with 2 yr to 4 yr of seed treatment use (mean = 5.7 ng/g) were not correlated with use history, and plant bioavailability was 6% of clothianidin soil residues. Average canola nectar concentrations were 0.6 ng/g and not correlated to use history or soil concentrations. Under typical cropping practices, therefore, clothianidin residues are not accumulating significantly in soil, plant bioavailability of residues in soil is limited, and exposure to pollinators will not increase over time in fields receiving multiple applications of clothianidin.


Assuntos
Abelhas/efeitos dos fármacos , Brassica rapa/química , Guanidinas/análise , Inseticidas/análise , Pólen/química , Poluentes do Solo/análise , Solo/química , Tiazóis/análise , Zea mays/química , Adsorção , Agricultura , Animais , Canadá , Europa (Continente) , Guanidinas/farmacocinética , Inseticidas/farmacocinética , Meio-Oeste dos Estados Unidos , Neonicotinoides , Resíduos de Praguicidas/análise , Néctar de Plantas/química , Tiazóis/farmacocinética
19.
Ecotoxicology ; 24(2): 262-78, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25381462

RESUMO

For more than 20 years, conservationists have agreed that amphibian populations around the world are declining. Results obtained through laboratory or mesocosm studies and measurement of contaminant concentrations in areas experiencing declines have supported a role of contaminants in these declines. The current study examines the effects of contaminant exposure to amphibians in situ in areas actually experiencing declines. Early larval Pseudacris regilla were translocated among Lassen Volcanic, Yosemite and Sequoia National Parks, California, USA and caged in wetlands in 2001 and 2002 until metamorphosis. Twenty contaminants were identified in tadpoles with an average of 1.3-5.9 (maximum = 10) contaminants per animal. Sequoia National Park, which had the greatest variety and concentrations of contaminants in 2001, also had tadpoles that experienced the greatest mortality, slowest developmental rates and lowest cholinesterase activities. Yosemite and Sequoia tadpoles and metamorphs had greater genotoxicity than those in Lassen during 2001, as determined by flow cytometry. In 2001 tadpoles at Yosemite had a significantly higher rate of malformations, characterized as hemimelia (shortened femurs), than those at the other two parks but no significant differences were observed in 2002. Fewer differences in contaminant types and concentrations existed among parks during 2002 compared to 2001. In 2002 Sequoia tadpoles had higher mortality and slower developmental rates but there was no difference among parks in cholinesterase activities. Although concentrations of most contaminants were below known lethal concentrations, simultaneous exposure to multiple chemicals and other stressors may have resulted in lethal and sublethal effects.


Assuntos
Anuros/metabolismo , Exposição Ambiental , Metamorfose Biológica/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anuros/anormalidades , Anuros/crescimento & desenvolvimento , California , Monitoramento Ambiental , Larva/crescimento & desenvolvimento , Larva/metabolismo , Estações do Ano
20.
J Hazard Mater ; 282: 68-74, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25282513

RESUMO

In the US, land application of biosolids has been utilized in government-regulated programs to recycle valuable nutrients and organic carbon that would otherwise be incinerated or buried in landfills. While many benefits have been reported, there are concerns that these practices represent a source of organic micropollutants to the environment. In this study, biosolids samples from a wastewater treatment plant in the Mid-Atlantic region of the US were collected approximately every 2 months over a 7-year period and analyzed for brominated diphenyl ethers (BDE-47, BDE-99, and BDE-209), triclosan, and triclocarban. During the collection period of 2005-2011, concentrations of the brominated diphenyl ethers BDE-47+BDE-99 decreased by 42%, triclocarban decreased by 47%, but BDE-209 and triclosan remained fairly constant. Observed reductions in contaminant concentrations could not be explained by different seasons or by volumetric changes of wastewaters arriving at the treatment plant and instead may be the result of the recent phaseout of BDE-47 and BDE-99 as well as potential reductions in the use of triclocarban.


Assuntos
Carbanilidas/análise , Éteres Difenil Halogenados/análise , Esgotos/análise , Triclosan/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Mid-Atlantic Region , Eliminação de Resíduos Líquidos
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