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Hullebusch, Eric D. van; Chatenet, Philippe; Deluchat, Véronique; Chazal, Philippe; Froissard, Didier; Botineau, Michel; Ghestem, Axel; Baudu, Michel

doi:10.1023/a:1026148914108

Cited by 32 publications

(7 citation statements)

References 40 publications

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“…Hosts and parasites may experience temporally diverse contamination events. For example, use of copper sulphate (an algicide) elevates concentrations in the water for days or weeks [14], whereas pollution from mining can raise metal levels for years [15].…”

Section: Introductionmentioning

confidence: 99%

Chronic contamination decreases disease spread: aDaphnia–fungus–copper case study

et al. 2012

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Chemical contamination and disease outbreaks have increased in many ecosystems. However, connecting pollution to disease spread remains difficult, in part, because contaminants can simultaneously exert direct and multi-generational effects on several host and parasite traits. To address these challenges, we parametrized a model using a zooplankton-fungus-copper system. In individual-level assays, we considered three sublethal contamination scenarios: no contamination, single-generation contamination (hosts and parasites exposed only during the assays) and multi-generational contamination (hosts and parasites exposed for several generations prior to and during the assays). Contamination boosted transmission by increasing contact of hosts with parasites. However, it diminished parasite reproduction by reducing the size and lifespan of infected hosts. Multi-generational contamination further reduced parasite reproduction. The parametrized model predicted that a single generation of contamination would enhance disease spread (via enhanced transmission), whereas multi-generational contamination would inhibit epidemics relative to unpolluted conditions (through greatly depressed parasite reproduction). In a population-level experiment, multi-generational contamination reduced the size of experimental epidemics but did not affect Daphnia populations without disease. This result highlights the importance of multi-generational effects for disease dynamics. Such integration of models with experiments can provide predictive power for disease problems in contaminated environments.

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Section: Introductionmentioning

confidence: 99%

Chronic contamination decreases disease spread: aDaphnia–fungus–copper case study

et al. 2012

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“…Esses resultados indicam que ambos os metais possuem afinidade pela MOD, óxidos, carbonatos, assim como pela fase coloidal. 4 A fração lábil corresponde a 29% do cobre na fração dissolvida nas amostras A e B, enquanto que o análogo para o zinco está próximo de 4 e 10%, respectivamente. Avaliando-se os dados de CC, observou-se que os agentes complexantes disponíveis nas águas do Reservatório do Iraí apresentam uma maior CC para o zinco, quando comparado ao cobre.…”

Section: Resultsunclassified

“…3,4 Portanto, avaliar a concentração total de um metal é insuficiente para inferir sobre seu comportamento e destino no ambiente, assim como sobre seus impactos na biota aquática. 1,3,5 Alguns autores consideram que espécies lábeis apresentam maior biodisponibilidade aos organismos aquáticos.…”

Section: Introductionunclassified

Análise de especiação de cobre e zinco empregando voltametria de redissolução anódica com pulso diferencial

Tonietto¹,

Grassi²

2012

Quím. Nova

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Recebido em 10/8/10; aceito em 3/6/11; publicado na web em 22/7/11 SPECIATION ANALYSIS OF COPPER AND ZINC USING DIFFERENTIAL PULSE ANODIC STRIPPING VOLTAMMETRY. This work describes methodologies for speciation analysis of the metals copper and zinc as total, total dissolved, labile, as well as complexation capacity (conditional stability constants and available ligand concentration), using the same technique, differential pulse anodic stripping voltammetry (DPASV). Several supporting electrolytes were tested, and the results showed that KNO 3 and HNO 3 resulted in voltamograms without interferences as well as excellent resolution for the total and labile fractions. The methodology using the DPASV technique allows a simple and low cost analysis of copper and zinc speciation, with high precision and sensitivity, with limits of quantification (LOQ) of 1.8 nmol L -1 for copper and 2.1 nmol L -1 for zinc.Keywords: anodic stripping voltammetry; speciation; trace metal. INTRODUÇÃOEstudos de especiação de metais são de grande importância para a avaliação de impactos ambientais, avaliações ecotoxicológicas, assim como para o entendimento do comportamento e destino dos metais em ambientes aquáticos.1 Informações sobre a reatividade, mobilidade e biodisponibilidade dos metais em águas naturais podem ser obtidas mediante estudos de especiação. A relação entre especiação dos elementos metálicos e toxicidade aos organismos é complexa e depende não somente da espécie química em questão, mas também do organismo exposto e da função fisiológica que o elemento metálico exerce no organismo.2 Sabe-se que os elementos cobre e zinco são essenciais aos organismos aquáticos, mas podem ser tóxicos quando encontrados em concentrações mais elevadas.3 Devido à complexidade da interação metais-organismo-ambiente, o uso de técnicas analíticas capazes de determinar diferentes espécies químicas com baixa manipulação amostral, tal qual a voltametria, assume destaque quanto à compreensão da dinâmica dos metais no ambiente.Sabe-se que o papel biogeoquímico dos metais correlaciona-se com suas formas físico-químicas, as quais incluem espécies associadas ao material particulado, coloidal e dissolvido.3,4 Portanto, avaliar a concentração total de um metal é insuficiente para inferir sobre seu comportamento e destino no ambiente, assim como sobre seus impactos na biota aquática. 1,3,5 Alguns autores consideram que espécies lábeis apresentam maior biodisponibilidade aos organismos aquáticos.6 Por outro lado, metais complexados a ligantes orgânicos são considerados de menor biodisponibilidade. 7A matéria orgânica dissolvida (MOD) exerce um papel fundamental na especiação dos metais-traço; os ligantes orgânicos possuem poder de complexação com metais, 8 cuja força de associação e quantidade de ligantes disponíveis variam com a categoria da MOD.9,10 Os estudos de especiação de metais podem ser realizados empregando-se diferentes abordagens e técnicas analíticas tais como a voltametria de redissolução anódica (DPASV) e voltametria de redissolução catódica (...

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“…Control of algal blooms with copper sulphate requires repeated treatments and is not recommended from a management perspective. It induces algal cell lysis (Jones & Orr, 1994), but is toxic to a large array of aquatic organisms, including macrophytes, zooplankton, molluscs and fish, and accumulates in the bottom sediments (van Hellebusch et al, 2003;de Oliveira-Filho, Lopes, & Paumgartten, 2004), with possible adverse long-term effects on the ecosystem (Schuler, Hoang, & Rand, 2008). Treatments with copper sulphate may also promote increases in bacterial biomass following mass plankton death (Havens, 1994), and repetitive application can favor growth of copper-resistant mutants in Microcystis populations (Garcia-Villada et al, 2004).…”

Section: Discussionmentioning

confidence: 99%

Microcystin and Algal Chlorophyll in Relation to Nearshore Nutrient Concentrations in Lake Winnipeg, Canada

Pip¹,

Bowman²

2014

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Microcystin (MC) and chlorophyll a (chl a) concentrations were examined at three nearshore stations during two consecutive ice-free seasons in relation to nitrate-N (NN), orthophosphate-P (OP) and other parameters in the south basin of Lake Winnipeg, Canada. While average nutrient levels were high in both years, chl a levels were significantly higher in 2011 than 2010, while the reverse was true for MC. However within each year, chl a was correlated with MC. Chl a was highly correlated with OP and NN in 2010, but less strongly with OP and not with NN in 2011. The higher chl a levels of 2011 were more strongly related to preceding than to concurrent OP and NN. MC was also strongly correlated with OP and (less) with NN in 2010, but only with chl a in 2011. The NN/OP ratio (NPR) was unrelated to chl a in either year, but was inversely correlated with MC in 2010. Cross-correlation analysis for 2010 showed that while MC lagged behind changes in chl a, OP, NN, and inversely behind NPR, correlations for these parameters (except NPR) were stronger for concurrent rather than delayed MC values. More vigorous blooms, as reflected by the phaeophytin/chl a ratio, were more toxic. While in a given season shifts in nutrients and NPR may signal impending changes in bloom density and toxicity, in some years additional factors besides nutrients appear to modify phytoplankton nutrient response. Nutrients remain a primary target for lake refurbishment strategies.

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Untitled

Cited by 32 publications

References 40 publications

Chronic contamination decreases disease spread: aDaphnia–fungus–copper case study

Chronic contamination decreases disease spread: aDaphnia–fungus–copper case study

Análise de especiação de cobre e zinco empregando voltametria de redissolução anódica com pulso diferencial

Microcystin and Algal Chlorophyll in Relation to Nearshore Nutrient Concentrations in Lake Winnipeg, Canada

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