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1.
J Am Mosq Control Assoc ; 38(3): 188-197, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901310

RESUMO

Two Culex pipiens form Pipiens colony strains and a field population of Cx. restuans from Michigan were susceptible and a Cx. pipiens form Molestus colony strain was comparatively less susceptible to a dose of 43 µg/ml of permethrin in Centers for Disease Control and Prevention (CDC) bottle bioassays. Using this diagnostic dose and these populations as controls, adult female Cx. pipiens and Cx. restuans were reared from egg rafts from 28 sites in Illinois, Ohio, Michigan, Iowa, Indiana, Wisconsin, and Minnesota. Tested mosquitoes showed high mortality in populations from 12 sites, less mortality (90-96%) at 9 sites, and less than 90% mortality from 7 sites during 30-min exposures. However, all tested populations showed 97-100% mortality at 60 min, indicating low phenotypic penetrance of resistance factors. These results indicate variation in susceptibility to permethrin in populations of West Nile virus vectors in the Great Lakes region of the United States, with evidence of modest resistance at 7 of 28 (25%) of the sampled populations.


Assuntos
Culex , Vírus do Nilo Ocidental , Animais , Feminino , Great Lakes Region , Mosquitos Vetores , Permetrina , Estados Unidos
2.
Sci Total Environ ; 827: 153974, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35218843

RESUMO

BACKGROUND: Fish is a dietary staple in the United States. Risk of exposure to persistent contaminants through fish consumption is a significant health concern. Great Lakes basin states, along with the US Environmental Protection Agency and the Great Lakes Consortium for Fish Consumption Advisories, have developed and continuously updated fish consumption advisories specifically for the Great Lakes basin residents. OBJECTIVES: To characterize Great Lakes basin residents' fish consumption and advisory awareness, we conducted a point-in-time survey to describe fish consumption habits and awareness of state and EPA/FDA fish advisories. METHODS: We used a randomized, address-based sampling approach to recruit respondents from the eight Great Lakes basin states. Weighted survey analysis procedures were used to estimate population prevalence of fish consumption habits, state and EPA/FDA advisory awareness, and demographic and background characteristics. Logistic regression models were used to assess the associations between demographic and background factors and fish consumption and awareness of advisories, respectively. RESULTS: About 92% of respondents, representing an estimated 61 million adults, reported eating fish in the last 12 months. About 64% of respondents only consumed commercial fish, and an estimated 5 million fish consumers exceeded the EPA/FDA recommended limit for fish meals. Minorities were more likely to exceed the EPA/FDA recommended limit. About half of the respondents were aware of state or EPA/FDA advisories; however, minorities and women were less aware of the EPA/FDA advisory. After adjusting for demographic characteristics, sportfish consumption was significantly associated with state advisory awareness; commercial fish consumption was significantly associated with EPA/FDA awareness. DISCUSSION: Most respondents only consumed commercial fish, but an estimated 18.6 million adults consumed sportfish. While half of the fish consumers were aware of state or EPA/FDA advisories, minorities and women continue to be less aware of fish advisories. Improved outreach strategies are needed to inform them about safe fish-consumption guidelines.


Assuntos
Contaminação de Alimentos , Lagos , Animais , Dieta , Feminino , Peixes , Great Lakes Region , Humanos , Inquéritos e Questionários , Estados Unidos
3.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34732584

RESUMO

Widespread human SARS-CoV-2 infections combined with human-wildlife interactions create the potential for reverse zoonosis from humans to wildlife. We targeted white-tailed deer (Odocoileus virginianus) for serosurveillance based on evidence these deer have angiotensin-converting enzyme 2 receptors with high affinity for SARS-CoV-2, are permissive to infection, exhibit sustained viral shedding, can transmit to conspecifics, exhibit social behavior, and can be abundant near urban centers. We evaluated 624 prepandemic and postpandemic serum samples from wild deer from four US states for SARS-CoV-2 exposure. Antibodies were detected in 152 samples (40%) from 2021 using a surrogate virus neutralization test. A subset of samples tested with a SARS-CoV-2 virus neutralization test showed high concordance between tests. These data suggest white-tailed deer in the populations assessed have been exposed to SARS-CoV-2.


Assuntos
Cervos/virologia , SARS-CoV-2/isolamento & purificação , Animais , COVID-19/epidemiologia , COVID-19/veterinária , Great Lakes Region/epidemiologia , Estudos Soroepidemiológicos
4.
Plant Dis ; 105(10): 3063-3071, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34702083

RESUMO

In many parts of the world including the Great Lakes region of North America, Cercospora leaf spot (CLS), caused by the fungal pathogen Cercospora beticola, is a major foliar disease of sugar beet (Beta vulgaris). Management of CLS involves an integrated approach which includes the application of fungicides. To guide fungicide application timings, disease prediction models are widely used by sugar beet growers in North America. While these models have generally worked well, they have not included information about pathogen presence. Thus, incorporating spore production and dispersal could make them more effective. The current study used sentinel beets to assess the presence of C. beticola spores in the environment early in the 2017 and 2018 growing seasons. Weather variables including air temperature, relative humidity, rainfall, leaf wetness, wind speed, and solar radiation were collected. These data were used to identify environmental variables that correlated with spore levels during a time when CLS is not generally observed in commercial fields. C. beticola spores were detected during mid-April both years, which is much earlier than previously reported. A correlation was found between spore data and all the weather variables examined during at least one of the two years, except for air temperature. In both years, spore presence was significantly correlated with rainfall (P < 0.0001) as well as relative humidity (P < 0.0090). Rainfall was particularly intriguing, with an adjusted R2 of 0.3135 in 2017 and 0.1652 in 2018. Efforts are ongoing to investigate information on spore presence to improve prediction models and CLS management.


Assuntos
Cercospora , Doenças das Plantas/microbiologia , Esporos Fúngicos , Tempo (Meteorologia) , Great Lakes Region , Estações do Ano
5.
Viruses ; 13(2)2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673082

RESUMO

Hepatitis B viruses belong to a family of circular, double-stranded DNA viruses that infect a range of organisms, with host responses that vary from mild infection to chronic infection and cancer. The white sucker hepatitis B virus (WSHBV) was first described in the white sucker (Catostomus commersonii), a freshwater teleost, and belongs to the genus Parahepadnavirus. At present, the host range of WSHBV and its impact on fish health are unknown, and neither genetic diversity nor association with fish health have been studied in any parahepadnavirus. Given the relevance of genomic diversity to disease outcome for the orthohepadnaviruses, we sought to characterize genomic variation in WSHBV and determine how it is structured among watersheds. We identified WSHBV-positive white sucker inhabiting tributaries of Lake Michigan, Lake Superior, Lake Erie (USA), and Lake Athabasca (Canada). Copy number in plasma and in liver tissue was estimated via qPCR. Templates from 27 virus-positive fish were amplified and sequenced using a primer-specific, circular long-range amplification method coupled with amplicon sequencing on the Illumina MiSeq. Phylogenetic analysis of the WSHBV genome identified phylogeographical clustering reminiscent of that observed with human hepatitis B virus genotypes. Notably, most non-synonymous substitutions were found to cluster in the pre-S/spacer overlap region, which is relevant for both viral entry and replication. The observed predominance of p1/s3 mutations in this region is indicative of adaptive change in the polymerase open reading frame (ORF), while, at the same time, the surface ORF is under purifying selection. Although the levels of variation we observed do not meet the criteria used to define sub/genotypes of human and avian hepadnaviruses, we identified geographically associated genome variation in the pre-S and spacer domain sufficient to define five WSHBV haplotypes. This study of WSHBV genetic diversity should facilitate the development of molecular markers for future identification of genotypes and provide evidence in future investigations of possible differential disease outcomes.


Assuntos
Cipriniformes/virologia , Doenças dos Peixes/virologia , Variação Genética/genética , Genoma Viral/genética , Vírus da Hepatite B/genética , Alberta , Animais , Marcadores Genéticos/genética , Great Lakes Region , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Filogeografia , Internalização do Vírus , Replicação Viral/genética
6.
Syst Parasitol ; 98(2): 119-130, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33687653

RESUMO

Henneguya Thélohan, 1892 is the second most species rich genus of myxozoans, with reports from freshwater and marine fish worldwide. In the Great Lakes region of North America, muskellunge Esox masquinongy is an important game fish species that serves as an apex predator in the ecosystems of many inland lakes. The myxozoan fauna of esocid fish, especially muskellunge, remains largely understudied. During fish health assessments, muskellunge were examined for parasitic infections and myxozoan pseudocysts were observed on gill clip wet mounts. When ruptured under pressure, the intralamellar pseudocysts released thousands of myxospores consistent with those of the genus Henneguya. The myxospores were 67.3-96.6 (79.1 ± 5.9) µm in total length. The spore body was 18.6-22.6 (20.9 ± 1.0) µm × 5.4-6.9 (6.3 ± 0.4) µm in valvular view and 3.5-4.0 (3.8 ± 0.3) µm wide in sutural view. The two pyriform polar capsules positioned at the anterior of the spore body were 6.4-7.7 (7.0 ± 0.4) µm × 1.8-2.1 (2.0 ± 0.1) µm and each contained a tightly coiled polar filament with 9-10 turns. Two tapering caudal processes extended from the posterior of the spore body and were 47.3-75.6 (58.3 ± 5.8) µm in length. Histologically, large intralamellar polysporic plasmodia were surrounded by plump pillar cells and a distinct layer of plasma. Mild inflammation was present peripherally, with small numbers of necrotic germinative cells and intraplasmodial phagocytes internally. Ribosomal 18S rRNA gene sequence data were obtained from three gill pseudocysts. The three ~2000-bp sequences were identical, but shared no significant similarity with any publicly available sequence data. Phylogenetic analyses demonstrated sequence data from this Henneguya fell within a well-supported clade of Henneguya spp. reported from northern pike Esox lucius in Europe. Based on the distinct morphological, histological and molecular data, this species is designated as Henneguya michiganensis n. sp. from muskellunge in Michigan, USA.


Assuntos
Esocidae/parasitologia , Brânquias/parasitologia , Myxozoa/classificação , Animais , Great Lakes Region , Myxozoa/anatomia & histologia , Myxozoa/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie
7.
Sci Total Environ ; 778: 146151, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33711592

RESUMO

This work presents the first assessment of temporal trends (2005-2016) for perfluoroalkyl acids (PFAAs) in top predator fish of the Laurentian Great Lakes except Lake Ontario, for which we provide a post-2008 update. Lake trout (Salvelinus namaycush) or walleye (Sander vitreus; Lake Erie only) collected annually from 2005 to 2016 were analyzed for 12 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkyl sulfonic acids (PFSAs) with carbon chain lengths between 4 and 16 (C4-C16). Individual analyte concentrations generally decreased in fish basin-wide between 2005 and 2016, including Lake Ontario lake trout previously found to lack declining PFAA concentrations up until 2008. Declining fish PFAA burden reflects a positive response to the industrial phase-outs of these chemicals. Notable exceptions to this general decline included most analytes in lake trout collected from Lake Superior near Keweenaw Point and C6 and C8 PFSAs and C9 PFCAs in Lake Erie lake trout and walleye, which exhibited constant or increasing concentrations in recent years. Recent increases in Lake Superior shoreline development and mobilization from increased sediment resuspension and contamination from biosolids-amended agricultural soils in the Lake Erie watershed are plausible explanations for these cases. However, data scarcity prohibits confirmation of these suspected causes. The lingering lack of declining concentrations noted in this study together with the ongoing evolution of the fluorinated chemical industry emphasize the vigilance needed to better understand how past and future emissions will affect the Great Lakes and global ecosystems.


Assuntos
Fluorcarbonetos , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Fluorcarbonetos/análise , Great Lakes Region , Lagos , Ontário , Poluentes Químicos da Água/análise
8.
Environ Sci Technol ; 55(6): 3765-3774, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33646760

RESUMO

Sport fish fillets and human sera (fish consumers) were collected in the Lake Superior and Lake Michigan basin and screened for novel contaminants using the isotopic profile deconvoluted chromatogram (IPDC) algorithm. The IPDC algorithm was extended beyond traditional Cl/Br filters to detect additional potential bioaccumulative and toxic (PBT) such as perfluoroalkyl substances (PFAS). The IPDC algorithm screened for approximately 13.5 million theoretical molecular formulas. Additional algorithm modules were developed to detect data independent MS/MS fragmentation products and a retention time index calculator using a series of 13C-labeled perfluoroalkyl carboxylic acids (13C-PFCAs). Ten potential compound classes were isolated including six untargeted PFAS, six homologue groups of polyfluorinated carboxylic acids, polyfluorinated telomer alcohols (PoFTOHs), two hydroxylated polychlorobiphenyls, pesticides, herbicides, antifungals, pharmaceuticals, artificial sweeteners, and personal care products with minimal postprocessing efforts. The algorithm isolated 48 ubiquitous PoFTOHs in both fish fillet and serum of fish consumers suggesting a region wide distribution of this class of compounds. The 3, 4, and 7 fluorine substituted PoFTOH were the most abundant congeners in both biological matrices.


Assuntos
Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Great Lakes Region , Humanos , Lagos , Michigan , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
9.
Sci Total Environ ; 779: 146284, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33744580

RESUMO

Industrial chemical contamination within coastal regions of the Great Lakes can pose serious risks to wetland habitat and offshore fisheries, often resulting in fish consumption advisories that directly affect human and wildlife health. Mercury (Hg) is a contaminant of concern in many of these highly urbanized and industrialized coastal regions, one of which is the Saint Louis River estuary (SLRE), the second largest tributary to Lake Superior. The SLRE has legacy Hg contamination that drives high Hg concentrations within sediments, but it is unclear whether legacy-derived Hg actively cycles within the food web. To understand the relative contributions of legacy versus contemporary Hg sources in coastal zones, Hg, carbon, and nitrogen stable isotope ratios were measured in sediments and food webs of SLRE and the Bad River, an estuarine reference site. Hg stable isotope values revealed that legacy contamination of Hg was widespread and heterogeneously distributed in sediments of SLRE, even in areas lacking industrial Hg sources. Similar isotope values were found in benthic invertebrates, riparian spiders, and prey fish from SLRE, confirming legacy Hg reaches the SLRE food web. Direct comparison of prey fish from SLRE and the Bad River confirmed that Hg isotope differences between the sites were not attributable to fractionation associated with rapid Hg bioaccumulation at estuarine mouths, but due to the presence of industrial Hg within SLRE. The Hg stable isotope values of game fish in both estuaries were dependent on fish migration and diet within the estuaries and extending into Lake Superior. These results indicate that Hg from legacy contamination is actively cycling within the SLRE food web and, through migration, this Hg also extends into Lake Superior via game fish. Understanding sources and the movement of Hg within the estuarine food web better informs restoration strategies for other impaired Great Lakes coastal zones.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Estuários , Peixes , Cadeia Alimentar , Great Lakes Region , Humanos , Lagos , Mercúrio/análise , Rios , Poluentes Químicos da Água/análise
10.
Environ Sci Technol ; 55(4): 2411-2421, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33522786

RESUMO

Polychlorinated naphthalenes (PCNs) were measured in lake trout and walleye over the period 2004-2018, utilizing isotope dilution techniques with high-resolution gas chromatography/high-resolution mass spectrometry to assess concentrations and toxic equivalence (TEQ). An age-trend model was applied to mitigate the effect of a changing lake trout age structure. Most Great Lakes Fish Monitoring and Surveillance Program sampling sites demonstrated significant half-life and percent decreases for lake trout total PCNs and total TEQ over the 2004-2018 period, the exceptions being Lake Erie lake trout and walleye which illustrated increasing concentrations. Great Lakes total PCN concentrations ranged between 5701 and 100 pg/g ww, whereas total PCN TEQ concentrations ranged between 8.89 and 0.13 pg-TEQ/g ww. Based on the average number of chlorines per naphthalene, we determined that the overall lake trout and walleye PCN congener distribution has significantly shifted to a lower-chlorinated composition in the Great Lakes (5.33 to 4.48 Cl/CN) and has resulted in a substantial 59.1% reduction of the overall total PCN TEQ burden. A prominent PCN concentration trend breakpoint was observed in Lake Ontario lake trout over the 2012-2016 period likely associated with hazardous waste cleanups, channel dredging, and spoils disposal in the Detroit River and western-basin of Lake Erie.


Assuntos
Lagos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Great Lakes Region , Naftalenos/análise , Ontário , Truta , Poluentes Químicos da Água/análise
11.
Environ Res ; 195: 110800, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33529648

RESUMO

Honey from Apis mellifera is a useful and inexpensive biomonitor for mapping metal distributions in urban centers. The sampling resolution of a biomonitoring survey (e.g., city versus global scale) determines which geochemical processes are reflected in the results. This study presents Pb isotopic compositions and metal concentrations in honey from around the world, sampled at varying resolutions: honey from Canada (n = 21), the United States (n = 111), Belgium (n = 25), and New Zealand (n = 10), with additional samples from Afghanistan, Brazil, Cuba, Germany, Liberia, Taiwan, and Turkey. Honey was sampled at high resolution in two uniquely different land-use settings (New York Metro Area and the Hawaiian island of Kaua'i), at regional-scale resolution in eastern North America (including the Great Lakes region), and Pb isotopic compositions of all samples were compared on a global scale. At high sampling resolution, metal concentrations in honey reveal spatially significant concentration gradients: in New York City, metals associated with human activity and city infrastructure (e.g., Pb, Sb, Ti, V) are more concentrated in honey collected within the city compared to honey from upstate New York, and metal concentrations in honey from Kaua'i suggest polluting effects of nearby agricultural operations. At lower resolution (regional and global scales), lead isotopic compositions of honey are more useful than metal concentrations in revealing large-scale Pb processes (e.g., the enduring legacy of global leaded gasoline use throughout the twentieth century) and the continental origin of the honey. Lead isotopic compositions of honey collected from N. America (especially from the eastern USA) are more radiogenic (206Pb/207Pb: 1.132-1.253, 208Pb/206Pb: 2.001-2.129) compared to European honey, and honey from New Zealand, which has the least radiogenic isotopic compositions measured in this study (206Pb/207Pb: 1.077-1.160, 208Pb/206Pb: 2.090-2.187). Thus, biomonitoring using honey at different resolutions reflects differing processes and, to some extent, a honey terroir defined by the Pb isotopic composition. The data presented here provide important (and current) global context for future studies that utilize Pb isotopes in honey. Moreover, this study exhibits community science in action, as most of the honey was collected by collaborators around the world, working directly with local apiarists and hobby beekeepers.


Assuntos
Mel , Animais , Abelhas , Bélgica , Brasil , Canadá , Cidades , Monitoramento Ambiental , Alemanha , Great Lakes Region , Mel/análise , Humanos , Isótopos , Chumbo , Cidade de Nova Iorque , Nova Zelândia , Taiwan , Turquia
12.
J Wildl Dis ; 57(1): 19-26, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33635967

RESUMO

Bacterial kidney disease, caused by Renibacterium salmoninarum, threatens salmonids worldwide. Following devastating mortality episodes in Oncorhynchus spp. in Lake Michigan, US, in the 1980s and infection rates >90%, pathogen prevalence has steadily declined to <5% over three decades in the three state-managed stocks. In this study, we sought to determine if the declining infection rates were associated with heightened circulating antibodies in state-managed Oncorhynchus spp. residing in the Lake Michigan watershed. A single-dilution, indirect enzyme-linked immunosorbent assay (ELISA) was modified to detect circulating antibodies against R. salmoninarum. Baseline values were delineated from naive chinook salmon (Oncorhynchus tshawytscha) and rainbow trout (Oncorhynchus mykiss). The assay was first used to assess primary antibody production over a 4-wk period in chinook salmon experimentally infected with R. salmoninarum. Mean antibody response was detected as early as 2 wk postinfection and continued to increase to the end of the observation period. The modified ELISA was then used to detect antibodies in serum samples collected from feral adult chinook salmon, coho salmon (Oncorhynchus kisutch), and steelhead trout (O. mykiss) returning to spawn at Lake Michigan weirs in 2009 and 2013. Results demonstrated that about 80% of feral Oncorhynchus spp. had measurable titers of circulating antibodies to R. salmoninarum. The relative ease and reasonable costs of this modified ELISA makes it a valuable serosurveillance tool for assessing the humoral immune status of feral salmonid populations.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Peixes/microbiologia , Oncorhynchus , Animais , Doenças dos Peixes/sangue , Doenças dos Peixes/imunologia , Great Lakes Region , Lagos , Renibacterium/imunologia
13.
Alcohol Clin Exp Res ; 45(4): 709-719, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33616244

RESUMO

BACKGROUND: Alcoholic hepatitis (AH) is a severe and life-threatening alcohol-associated liver disease. Only a minority of heavy drinkers acquires AH and severity varies among affected individuals, suggesting a genetic basis for the susceptibility to and severity of AH. METHODS: A cohort consisting of 211 patients with AH and 176 heavy drinking controls was genotyped for five variants in five candidate genes that have been associated with chronic liver diseases: rs738409 in patatin-like phospholipase domain-containing protein 3 (PNPLA3), rs72613567 in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13), rs58542926 in transmembrane 6 superfamily member 2 (TM6SF2), rs641738 in membrane bound O-acyltransferase domain containing 7 (MBOAT7), and a copy number variant in the haptoglobin (HP) gene. We tested the effects of individual variants and the combined/interacting effects of variants on AH risk and severity. RESULTS: We found significant associations between AH risk and the risk alleles of rs738409 (p = 0.0081) and HP (p = 0.0371), but not rs72613567 (p = 0.3132), rs58542926 (p = 0.2180), or rs641738 (p = 0.7630), after adjusting for patient's age and sex. A multiple regression model indicated that PNPLA3 rs738409:G [OR = 1.59 (95% CI: 1.15-2.22), p = 0.0055] and HP*2 [OR = 1.38 (95% CI: 1.04-1.82), p = 0.0245], when combined and adjusted for age and sex also had a large influence on AH risk among heavy drinkers. In the entire cohort, variants in PNPLA3 and HP were associated with increased total bilirubin and Model for End-stage Liver Disease (MELD) score, both measures of AH severity. The HSD17B13 rs72613567:AA allele was not found to reduce risk of AH in patients carrying the G allele of PNPLA3 rs738409 (p = 0.0921). CONCLUSION: PNPLA3 and HP genetic variants increase AH risk and are associated with total bilirubin and MELD score, surrogates of AH severity.


Assuntos
17-Hidroxiesteroide Desidrogenases/genética , Aciltransferases/genética , Haptoglobinas/genética , Hepatite Alcoólica/genética , Lipase/genética , Proteínas de Membrana/genética , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Frequência do Gene , Predisposição Genética para Doença , Great Lakes Region/epidemiologia , Hepatite Alcoólica/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Virginia/epidemiologia
14.
Toxins (Basel) ; 13(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435505

RESUMO

Cyanobacterial harmful algal bloom (CyanoHAB) proliferation is a global problem impacting ecosystem and human health. Western Lake Erie (WLE) typically endures two highly toxic CyanoHABs during summer: a Microcystis spp. bloom in Maumee Bay that extends throughout the western basin, and a Planktothrix spp. bloom in Sandusky Bay. Recently, the USA and Canada agreed to a 40% phosphorus (P) load reduction to lessen the severity of the WLE blooms. To investigate phosphorus and nitrogen (N) limitation of biomass and toxin production in WLE CyanoHABs, we conducted in situ nutrient addition and 40% dilution microcosm bioassays in June and August 2019. During the June Sandusky Bay bloom, biomass production as well as hepatotoxic microcystin and neurotoxic anatoxin production were N and P co-limited with microcystin production becoming nutrient deplete under 40% dilution. During August, the Maumee Bay bloom produced microcystin under nutrient repletion with slight induced P limitation under 40% dilution, and the Sandusky Bay bloom produced anatoxin under N limitation in both dilution treatments. The results demonstrate the importance of nutrient limitation effects on microcystin and anatoxin production. To properly combat cyanotoxin and cyanobacterial biomass production in WLE, both N and P reduction efforts should be implemented in its watershed.


Assuntos
Toxinas Bacterianas/toxicidade , Cianobactérias/fisiologia , Proliferação Nociva de Algas , Lagos/microbiologia , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Clorofila A/química , Great Lakes Region , Lagos/química
15.
Environ Pollut ; 270: 116073, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261964

RESUMO

To meet human food and fiber needs in an environmentally and economically sustainable way, we must improve the efficiency of waste, water, and nutrient use by converting vast quantities of agricultural and food waste to renewable bioproducts. This work converts waste cherry pits, an abundant food waste in the Great Lakes region, to biochars and activated biochars via slow pyrolysis. Biochars produced have surface areas between 206 and 274 m2/g and increased bioavailability of Fe, K, Mg, Mn, and P. The biochars can be implemented as soil amendments to reduce nutrient run-off and serve as a valuable carbon sink (biochars contain 74-79% carbon), potentially mitigating harmful algal blooms in the Great Lakes. CO2-activated biochars have surface areas of up to 629 m2/g and exhibit selective metal adsorption for the removal of metals from simulated contaminated drinking water, an environmental problem plaguing this region. Through sustainable waste-to-byproduct valorization we convert this waste food biomass into biochar for use as a soil amendment and into activated biochars to remove metals from drinking water, thus alleviating economic issues associated with cherry pit waste handling and reducing the environmental impact of the cherry processing industry.


Assuntos
Resíduos Industriais , Eliminação de Resíduos , Carvão Vegetal/análise , Alimentos , Great Lakes Region , Humanos , Lagos , Solo , Qualidade da Água
16.
Genome Biol Evol ; 13(2)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33247716

RESUMO

Local adaptation can drive diversification of closely related species across environmental gradients and promote convergence of distantly related taxa that experience similar conditions. We examined a potential case of adaptation to novel visual environments in a species flock (Great Lakes salmonids, genus Coregonus) using a new amplicon genotyping protocol on the Oxford Nanopore Flongle and MinION. We sequenced five visual opsin genes for individuals of Coregonus artedi, Coregonus hoyi, Coregonus kiyi, and Coregonus zenithicus. Comparisons revealed species-specific differences in a key spectral tuning amino acid in rhodopsin (Tyr261Phe substitution), suggesting local adaptation of C. kiyi to the blue-shifted depths of Lake Superior. Ancestral state reconstruction demonstrates that parallel evolution and "toggling" at this amino acid residue has occurred several times across the fish tree of life, resulting in identical changes to the visual systems of distantly related taxa across replicated environmental gradients. Our results suggest that ecological differences and local adaptation to distinct visual environments are strong drivers of both evolutionary parallelism and diversification.


Assuntos
Evolução Molecular , Proteínas de Peixes/genética , Rodopsina/genética , Salmonidae/genética , Animais , Great Lakes Region , Lagos , Sequenciamento por Nanoporos
17.
FEMS Microbiol Lett ; 367(23)2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33354724

RESUMO

Many aquatic environments are at risk for oil contamination and alkanes are one of the primary constituents of oil. The alkane hydroxylase (AlkB) is a common enzyme used by microorganisms to initiate the process of alkane-degradation. While many aspects of alkane bioremediation have been studied, the diversity and evolution of genes involved in hydrocarbon degradation from environmental settings is relatively understudied. The majority of work done to-date has focused on the marine environment. Here we sought to better understand the phylogenetic diversity of alkB genes across marine and freshwater settings using culture-independent methods. We hypothesized that there would be distinct phylogenetic diversity of alkB genes in freshwater relative to the marine environment. Our results confirm that alkB has distinct variants based on environment while our diversity analyses demonstrate that freshwater and marine alkB communities have unique responses to oil amendments. Our results also demonstrate that in the marine environment, depth is a key factor impacting diversity of alkB genes.


Assuntos
Bactérias , Citocromo P-450 CYP4A/genética , Genes Bacterianos/genética , Variação Genética , Filogenia , Oceano Atlântico , Bactérias/classificação , Bactérias/enzimologia , Bactérias/genética , Citocromo P-450 CYP4A/metabolismo , Great Lakes Region , Petróleo/metabolismo , Salinidade , Microbiologia da Água
18.
Environ Sci Technol ; 54(23): 15035-15045, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33167618

RESUMO

Fish have been used for decades as bioindicators for assessing toxic contaminants in the Great Lakes ecosystem. Routine environmental monitoring programs target predetermined compounds that do not reflect the complete exposure of chemicals to biota and do not provide the complete halogenated fingerprint of the biota. In the current work, a nontargeted screening method was developed using a two-dimensional gas chromatograph coupled to a high-resolution time-of-flight mass spectrometer and was applied to 149 edible fish fillets from different species in the Great Lakes to characterize a more robust set of halogenated organic compounds across species and among lakes. Lake Ontario had the largest number of novel halogenated organic compounds (NHOCs). Seven NHOCs were observed in species from all lakes, indicating that this regional signature was not species-dependent. Hierarchical cluster analysis showed identical NHOC profiles between bottom dwelling and pelagic species. The NHOCs were grouped into seven clusters with similar structures and potentially similar environmental behaviors. Seven of the 29 NHOCs likely containing methoxy or ethoxy groups on a benzene or benzene-methanol backbone were clustered into one group with similar retention times. Five NHOCs were clustered with legacy contaminants that likely have similar structures or are their degradation products.


Assuntos
Lagos , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Great Lakes Region , Ontário , Poluentes Químicos da Água/análise
19.
J Environ Qual ; 49(4): 896-908, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016491

RESUMO

Recreational water quality is currently monitored at Sandpoint Beach on Lake St. Clair using culture-based enumeration of Escherichia coli. Using water quality and weather data collected over 4 yr, several multiple linear regression (MLR)-based models were developed for near real-time prediction of E. coli concentration and were tested using independent data from the fifth year. Model performance was assessed by the determination of metrics such as RMSE, accuracy, specificity, sensitivity, and area under the receiver operating characteristic curve (AUROC). Each of the developed MLR models described herein resulted in increased correct responses for both exceedance and non-exceedance of the applicable standard as compared to predictions based on E. coli measurements (persistence models, using the previous day's E. coli concentration), which is the method currently being used. The AUROC values for persistence models are between 0.5 and 0.6, as compared to >0.7 for all the MLR models described herein. Among the MLR models, model performance improved when qualitative sky weather condition, which is commonly reported but was not previously used in similar models, was included. To select the best model, a principal coordinate analysis was used to combine multiple model performance metrics and provide a more sensitive tool for model comparison. Although models developed using 2, 3, and 4 yr of monitoring data provided reasonable performance, the model developed using the most recent 2-yr data was marginally better. Thus, data from the most recent 2 yr are likely sufficient as a training dataset for updating the MLR model for Sandpoint Beach in the future.


Assuntos
Praias , Escherichia coli , Monitoramento Ambiental , Great Lakes Region , Qualidade da Água
20.
Environ Sci Technol ; 54(22): 14352-14360, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33103889

RESUMO

Legacy halogenated contaminants have been monitored in the Great Lakes for decades, but there are many additional unknown halogenated contaminants potentially affecting the Great Lakes ecosystem. To address this concern, lake trout (Salvelinus namaycush) were collected in 2005/2006 and 2015/2016 from each lake and screened for previously unidentified compounds. The isotopic profile deconvoluted chromatogram algorithm was used to isolate unknown halogenated components using high-resolution mass spectrometry data files generated by an atmospheric pressure gas chromatography-quadrupole time-of-flight mass spectrometer operated in positive and negative modes. The temporal and spatial differences in the newly detected features were used to isolate new potential contaminants. Decadal differences in the unknown halogenated compounds (or features) were compared with the total polychlorinated biphenyl concentration trends. Greater than 2000 unknown halogenated features were detected. As expected, Lake Superior contained the lowest number of unknown halogenated features, whereas Lake Ontario contained the highest. Unknown features tended to have fewer Cl and/or Br atoms compared to traditional legacy contaminant features typically monitored. Diverse patterns of unknown halogenated compounds between lakes suggested that there continues to be unidentified sources of halogenated contaminants in the Great Lakes missed by current monitoring programs.


Assuntos
Lagos , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Great Lakes Region , Ontário , Poluentes Químicos da Água/análise
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