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Mangroves are critically threatened by human activities, despite the important ecosystem functions and services they provide. Mangroves in Cameroon represent no exception to the worldwide trend of mangrove destruction, especially around Douala, on the Wouri river estuary. In two sites around Douala, we assessed the presence of sterols, PAHs, PCBs, DEHP, DDT and its metabolite p,p'-DDE and potentially toxic metals in sediment samples. As a proxy of ecological quality, we measured the diversity and abundance of macrobenthos assemblages. We detected p,p'-DDE contamination, with concentrations higher than 3 μg kg− 1 in 16 out of 26 samples which were attributed to recent widespread use of DDT. The detection of sterols revealed faecal contamination. Significant sensitivity of the macrobenthos to contaminants was revealed, with possible implications on the overall mangrove vulnerability to climate change and on the provision of ecosystem services to local populations., SCOPUS: ar.j, info:eu-repo/semantics/published

O texto reflete acerca da temática das violações aos direitos das mulheres indígenas no contexto brasileiro. Ao fazer isto, apresenta-se uma abordagem das violências que atingem as mulheres indígenas nos variados contextos, e a agência feminina na elaboração de estratégicas para o enfrentamento de tais conflitos e violações. Tais questões são apresentadas dentro do debate sobre os direitos dos povos indígenas e os direitos humanos das mulheres, demonstrando que as problemáticas vivenciadas pelas mulheres indígenas não se deslocam das problemáticas gerais de seus povos, embora comportem especificidades na compreensão da violência contra as mulheres na intersecção com a etnicidade.

O texto reflete acerca da temática das violações aos direitos das mulheres indígenas no contexto brasileiro. Ao fazer isto, apresenta-se uma abordagem das violências que atingem as mulheres indígenas nos variados contextos, e a agência feminina na elaboração de estratégicas para o enfrentamento de tais conflitos e violações. Tais questões são apresentadas dentro do debate sobre os direitos dos povos indígenas e os direitos humanos das mulheres, demonstrando que as problemáticas vivenciadas pelas mulheres indígenas não se deslocam das problemáticas gerais de seus povos, embora comportem especificidades na compreensão da violência contra as mulheres na intersecção com a etnicidade.

Coastal lagoons are constantly subjected to releases of chemical pollutants, and so organisms may be exposed to such toxicants. This study investigated through a multivariate approach the physiological status of bivalve Ruditapes philippinarum, farmed in Sacca di Goro lagoon. Biomarkers at different levels of biological organization (catalase, superoxide dismutase, genotoxicity, reburrowing behavior) were evaluated at three sites exposed to different environmental conditions. A seasonal trend was observed, and micronucleus frequency was significantly lowest at the relatively pristine reference site. Enzymatic activity toward oxyradicals be quite efficient since variations in responsiveness were not consistent. However, behavioral impairment was observed in reburrowing rates. Sediment concentrations showed low PAH levels and high natural levels of trace metals Cr and Ni. DistLM statistical analysis revealed a non-significant relationship between selected biomarkers and xenobiotics. Therefore other potentially toxic compounds in admixture at low doses may be involved in driving differing spatial distribution of physiological impairment.

Aquatic ecosystems are the final sink for most of xenobiotic introduced in the environment, especially persistent organic pollutants. Most of the freshwater and coastal organisms are exposed simultaneously to different classes of chemicals, and their physiology may be affected by toxic chemical even at low environmental concentrations with a cascade event on population dynamics. Identifying ecotoxicological effects requires descriptors that are sensitive to changes in exposure and thus can indicate information at different levels of biological organisation (i.e. communities, subindividual level). The present work aims to investigate biochemical biomarkers and bioindicators in aquatic invertebrates able to detect biological effects and predict risk of toxicity, with a special focus paid to the requirements of current EU regulation. Therefore, the present work faced on different kinds of approach identified to be efficient tools within the context of the WFD requirements (Water Frame Directive, 2000/60/EC), for investigative and operational monitoring. Work include the SPEAR approach as trait based indicator descriptor of freshwater aquatic macroinvertebrates communities, able to diagnose pesticide contamination in aquatic ecosystems. Further diagnostic approaches in environmental status are included, as assay representing biological responses for different enzymes involved in the aerobic (CCO) and antioxidant responses, (SOD, and CAT), behavioural endpoints, and genotoxicity biomarker associated with micronuclei frequency in bivalve species (Ruditapes philipphinarum and Mya arenaria).

The aim of the current study was to investigate effects of temperature and a mixture of herbicides on the physiological status of the bivalve Mya arenaria. Bivalves acclimated to two temperatures (7 and 188C) were exposed for 28 d to 0.01 mg/L of a pesticide formulation containing dichlorophenoxyacetic acid (2,4-D), 2-(2-methyl-4-chlorophenoxy) propionic acid (mecoprop), and 3,6- dichloro-2-methoxybenzoic acid (dicamba). At days 7, 14, and 28, mortality, immune parameters (hemocyte number, phagocytic activity, and efficiency), biomarkers of oxidative stress (catalase [CAT] and superoxide dismutase [SOD] activities and malondialdehyde[MDA] content), the metabolic enzyme cytochrome C oxidase (CCO), a biomarker of pesticide exposure (acetylcholinesterase [AChE]), and the activity of an enzyme related to gametogenesis (aspartate transcarbamylase [ATCase]) were monitored in clam tissues. Gonadosomatic index (GSI), condition factor (CF), and sex were also assessed. In clams acclimated to 78C, exposure to pesticide enhanced CCO activity and CF and decreased MDA content, hemocyte number, CAT, and SOD activities. In clams kept at 188C,pesticide effects appeared minor compared with samples kept at 78C. In bivalves acclimated to 188C, CCO, SOD, and ATCase activity and MDA content were enhanced, and hemocyte number, CAT, and AchE activities and phagocytosis were suppressed. In samples exposed to pesticides, increased temperature enhanced MDA content and CCO and SOD activity and suppressed hemocyte number and CAT and AchE activity. A gradual sexual maturation was observed in both sexes through experimental time, but females had a higher sensitivity to temperature and pesticides compared to males. Increased temperature altered the ability of the sentinel species Mya arenaria to respond to pesticide exposures. Further work is needed to understand the impacts of increasing temperature on the whole St. Lawrence estuary ecosystem.

Aquatic ecosystems are the final sink for most of xenobiotic introduced in the environment, especially persistent organic pollutants. Most of the freshwater and coastal organisms are exposed simultaneously to different classes of chemicals, and their physiology may be affected by toxic chemical even at low environmental concentrations with a cascade event on population dynamics. Identifying ecotoxicological effects requires descriptors that are sensitive to changes in exposure and thus can indicate information at different levels of biological organisation (i.e. communities, subindividual level). The present work aims to investigate biochemical biomarkers and bioindicators in aquatic invertebrates able to detect biological effects and predict risk of toxicity, with a special focus paid to the requirements of current EU regulation. Therefore, the present work faced on different kinds of approach identified to be efficient tools within the context of the WFD requirements (Water Frame Directive, 2000/60/EC), for investigative and operational monitoring. Work include the SPEAR approach as trait based indicator descriptor of freshwater aquatic macroinvertebrates communities, able to diagnose pesticide contamination in aquatic ecosystems. Further diagnostic approaches in environmental status are included, as assay representing biological responses for different enzymes involved in the aerobic (CCO) and antioxidant responses, (SOD, and CAT), behavioural endpoints, and genotoxicity biomarker associated with micronuclei frequency in bivalve species (Ruditapes philipphinarum and Mya arenaria).

Gli ecosistemi acquatici sono il comparto ambientale finale per molti contaminanti introdotti nell’ambiente, specialmente per quelli persistenti, provenienti da diverse attività antropiche. Gli organismi acquatici sono esposti simultaneamente a differenti classi di composti chimici e, la loro fisiologia può esserne affetta anche da basse concentrazioni ambientali che ne determinano un effetto a cascata drammatico sull’intero ciclo vitale delle stesse. Per identificare gli effetti ecotossicologici si devono scegliere delle variabili di studio che sono sensibili a cambiamenti di esposizione e quindi possono registrare informazioni a differenti livelli di organizzazione biologica (ad es.: comunità, specie, alterazioni cellulari, molecolari). Il presente lavoro ha come scopo di studiare biomarker biochimici e bioindicatori su invertebrati acquatici capaci di rispondere all’effetto dei contaminanti e predirne il rischio di tossicità, requisito fondamentale dell’attuale legislazione comunitaria ambientale. Questo lavoro, nell’ambito della Water Frame Directive (WFD), affronta questa tematica con diversi tipi di approccio per implementare un sistema di monitorizzazione efficiente. Lo SPEAR ad esempio è in grado di diagnosticare la contaminazione di ecosistemi acquatici da pesticidi operando a livello di comunità di invertebrati acquatici. Inoltre si sono presi in considerazione anche biomarker a livello cellulare in bivalvi (Tapes philipphinarum and Mya arenaria): attività enzimatiche coinvolti nelle risposte aerobiche (CCO) e antiossidative (SOD and CAT), risposte genotossicologiche come la frequenza dei micronuclei, e, infine, a livello di organismo, risposte di carattere comportamentale., Aquatic ecosystems are the final sink for most of contaminants introduced in the environment, especially persistent organic pollutants coming from different human activities. Most of the freshwater and coastal organisms are exposed simultaneously to different classes of chemicals, and their physiology may be affected by toxic chemical even at low environmental concentrations with a cascade event on population dynamics. Identifying ecotoxicological effects requires descriptors that are sensitive to changes in exposure and thus can indicate information at different levels of biological organisation (i.e. communities, sub-individual level). The present work aims to investigate biochemical biomarkers and bioindicators in aquatic invertebrates able to detect biological effects and predict risk of toxicity, with a special focus paid to the requirements of current EU regulation. Therefore, the present work faced on different kinds of approach identified to be efficient tools within the context of the WFD requirements (Water Frame Directive, 2000/60/EC), for investigative and operational monitoring. Work include the SPEAR approach as trait based indicator descriptor of freshwater aquatic macroinvertebrates communities, able to diagnose pesticide contamination in aquatic ecosystems. Further diagnostic approaches in environmental status are included, as assay representing biological responses for different enzymes involved in the aerobic (CCO) and antioxidant responses, (SOD, and CAT), behavioural endpoints, and genotoxicity biomarker associated with micronuclei frequency in bivalve species (Tapes philipphinarum and Mya arenaria).

To detect effects of pesticides on non-target freshwater organisms the Species at risk (SPEAR(pesticides)) bioindicator based on biological traits was previously developed and successfully validated over different biogeographical regions of Europe using species-level data on stream invertebrates. Since many freshwater biomonitoring programmes have family-level taxonomic resolution we tested the applicability of SPEAR(pesticides) with family-level biomonitoring data to indicate pesticide effects in streams (i.e. insecticide toxicity of pesticides). The study showed that the explanatory power of the family-level SPEAR(fm)(pesticides) is not significantly lower than the species-level index. The results suggest that the family-level SPEAR(fm)(pesticides) is a sensitive, cost-effective, and potentially European-wide bioindicator of pesticide contamination in flowing waters. Class boundaries for SPEAR(pesticides) according to EU Water Framework Directive are defined to contribute to the assessment of ecological status of water bodies.

To detect effects of pesticides on non-target freshwater organisms the Species at risk (SPEAR(pesticides)) bioindicator based on biological traits was previously developed and successfully validated over different biogeographical regions of Europe using species-level data on stream invertebrates. Since many freshwater biomonitoring programmes have family-level taxonomic resolution we tested the applicability of SPEAR(pesticides) with family-level biomonitoring data to indicate pesticide effects in streams (i.e. insecticide toxicity of pesticides). The study showed that the explanatory power of the family-level SPEAR(fm)(pesticides) is not significantly lower than the species-level index. The results suggest that the family-level SPEAR(fm)(pesticides) is a sensitive, cost-effective, and potentially European-wide bioindicator of pesticide contamination in flowing waters. Class boundaries for SPEAR(pesticides) according to EU Water Framework Directive are defined to contribute to the assessment of ecological status of water bodies.