RESUMEN
Salmonids were first introduced into the Chilean fresh waters in the 1880s, and c. 140 years later, they are ubiquitous across Chilean rivers, especially in the southern pristine fresh waters. This study examined the brown trout (Salmo trutta) and native taxa ecology in two adjacent but contrasting rivers of Chilean Patagonia. During spring 2016 and spring-fall 2017 we examined the variation in benthic macroinvertebrate and fish community composition and characterized fish size structure, stomach contents, and stable isotopes (δ13 C and δ15 N) to understand population structure, fish diet, and trophic interactions between S. trutta and native taxa. The native Galaxias maculatus (puye) dominated the fish community (74% of abundance). S. trutta was less abundant (16% of survey catch) but dominated the fish community (over 53%) in terms of biomass. S. trutta showed distinct diets (stomach content analysis) in the two rivers, and individuals from the larger river were notably more piscivorous, consuming native fish with a relatively small body size (<100-mm total length). Native fishes were isotopically distinct from S. trutta, which showed a wider isotopic niche in the smaller river, indicating that their trophic role was more variable than in the larger river (piscivorous). This study provides data from the unstudied pristine coastal rivers in Patagonia and reveals that interactions between native and introduced species can vary at very local spatial scales.
Asunto(s)
Osmeriformes , Salmonidae , Animales , Ríos/química , Trucha , Agua DulceRESUMEN
Industrial wastewaters and urban discharges contain complex mixtures of chemicals capable of impacting reproductive performance in freshwater fish, called endocrine-disrupting compounds (EDCs). In Chile, the issue was highlighted by our group beginning over 15 years ago, by analyzing the impacts of pulp and paper mill effluents (PPME) in the Biobio, Itata, and Cruces River basins. All of the rivers studied are important freshwater ecosystems located in the Mediterranean region of Central Chile, each with a unique fish biodiversity. Sequentially, we developed a strategy based on laboratory assays, semicontrolled-field experiments (e.g., caging) and wild fish population assessments to explore the issue of reproductive impacts on both introduced and native fish in Chile. The integration of watershed, field, and laboratory studies was effective at understanding the endocrine responses in Chilean freshwater systems. The studies demonstrated that regardless of the type of treatment, pulp mill effluents can contain compounds capable of impacting endocrine systems. Urban wastewater treatment plant effluents (WWTP) were also investigated using the same integrated strategy. Although not directly compared, PPME and WWTP effluent seem to cause similar estrogenic effects in fish after waterborne exposure, with differing intensities. This body of work underscores the urgent need for further studies on the basic biology of Chilean native fish species, and an improved understanding on reproductive development and variability across Chilean ecosystems. The lack of knowledge of the ontogeny of Chilean fish, especially maturation and sexual development, with an emphasis on associated habitats and landscapes, are impediment factors for their conservation and protection against the threat of EDCs. The assessment of effects on native species in the receiving environment is critical for supporting and designing protective regulations and remediation strategies, and for conserving the unique Chilean fish biodiversity.
Asunto(s)
Disruptores Endocrinos/farmacología , Peces/fisiología , Aguas Residuales , Animales , Chile , Ecosistema , Sistema Endocrino/efectos de los fármacos , Monitoreo del Ambiente , Estrógenos/farmacología , Humanos , Reproducción/efectos de los fármacos , Ríos/química , Eliminación de Residuos Líquidos , Aguas Residuales/química , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/farmacologíaRESUMEN
In Brazil, there are no unified and effective environmental monitoring models for bodies of water. Thus, several methodologies are used that result in information that is often difficult to compare, especially for stakeholders involved in regional water management. Studies in some countries such as Australia, Chile, the USA, and Sweden use the monitoring model implemented in Canada that was developed in the early 1990s. This model was designed to evaluate whether the current environmental regulations are sufficiently protective for pulp and paper effluents and for metal mining effluents. In this study, the Canadian Environmental Effects Monitoring methodologies were applied to three different Brazilian river basins, with the goal of constructing a framework for monitoring environmental effects. Pilot studies were carried out in the estuarine regions of the Benevente, Jucu, and Santa Maria da Vitória river basins, which are important rivers in the state of Espírito Santo. Evaluations included fish health, bioaccumulation studies, benthic invertebrate survey, and physical-chemical analyses of water and sediment. The quality of the environments was evaluated by means of seasonal samplings and comparisons between discharge, upstream, and downstream areas. This study made it possible to identify appropriate fish species to be used in environmental effects monitoring and the environmental quality of the rivers themselves as well as knowledge and policy gaps to implement such monitoring programs in Brazil. The study raises questions about the adequacy of Brazilian environmental legislation concerning tidal rivers.
Asunto(s)
Monitoreo del Ambiente/métodos , Estuarios , Peces/crecimiento & desarrollo , Ríos , Contaminantes Químicos del Agua/análisis , Animales , Brasil , Invertebrados/crecimiento & desarrollo , Proyectos Piloto , Ríos/químicaRESUMEN
Bioactive substances in the Biobio River Basin in Chile were examined by deploying Semi Permeable Membrane Devices (SPMDs) upstream and downstream of 4 pulp mill effluent discharges. Androgenic and estrogenic activity of SPMD extracts were then evaluated using in vitro fish sex steroid receptor binding assays. The results indicated the occurrence of estrogenic type compounds associated with one of the mill discharges. A significant correlation among the presence of these compounds, an increase in gonadosomatic index GSI and induction of hepatic EROD activity of two native fish species was observed. However, no significant presence of mature oocytes in female gonads was detected. Although EROD induction was observed in sites impacted by mill effluents, an increase of its activity occurred towards the downstream areas, suggesting other non-mill sources. More research is needed to understand the environmental changes in context of the new technological improvements in treatment systems to MBBR (Moving Bed Biofilm Reactor) recently implemented by the pulp mill industries.
Asunto(s)
Disruptores Endocrinos/toxicidad , Peces/metabolismo , Residuos Industriales/efectos adversos , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Ríos/química , Contaminantes Químicos del Agua/toxicidad , Animales , Reactores Biológicos , Chile , Citocromo P-450 CYP1A1/metabolismo , Disruptores Endocrinos/análisis , Monitoreo del Ambiente/métodos , Femenino , Peces/crecimiento & desarrollo , Residuos Industriales/análisis , Industrias , Ligandos , Hígado/efectos de los fármacos , Hígado/enzimología , Reproducción/efectos de los fármacos , Estaciones del Año , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodosRESUMEN
Lagoons are important nursery habitats for fishes but are often sites of intense human activity including wastewater discharges. The goal of this research was to compare stable nitrogen (δ15N) and carbon (δ13C) isotopes, total mercury (THg) and other metal levels in four selected fish species among sites with different levels of untreated sewage discharge inside Barra de Navidad coastal lagoon in the Mexican Pacific. Three species from sites heavily impacted by sewage showed higher δ15N and δ13C compared to those from non-impacted sites. In addition, the highest concentrations of THg were present in fish of two species (Sciades guatemalensis and Diapterus brevirostris) collected at the two most impacted sites, and exceeded the 0.2µg/g ww threshold believed to be protective of adult and juvenile fish. No individuals of Achirus mazatlanus and Mugil curema exceeded this threshold, and liver somatic index and condition did not distinguish high from low impacted sites for all species. In general, the metal levels differed among species but not sites, and were lower than what has been measured in fishes elsewhere. The study also provides the first information on several fish species for coastal areas of Mexico, suggests that THg and isotopes can distinguish sewage-impacted sites, and can serve as a baseline for future studies.
Asunto(s)
Monitoreo del Ambiente/métodos , Peces/metabolismo , Mercurio/análisis , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis , Animales , Isótopos de Carbono/análisis , Ecosistema , Peces/crecimiento & desarrollo , Humanos , Mercurio/metabolismo , México , Isótopos de Nitrógeno/análisis , Contaminantes Químicos del Agua/metabolismoRESUMEN
Polychlorinated biphenyl (PCB) levels were determined in the faeces of three Antarctic Peninsula penguin species to assess viability as a non-invasive approach for sampling PCBs in Antarctic biota. These determinations were complemented with stable isotope and porphyrins assessments, and together this methodology determined the role of diet and metabolic disruption in penguins. Up to 60% of the collected faecal samples evidenced low molecular weight PCBs, of which, the more volatile compounds were predominant, in agreement with previous results. The highest PCB levels were reported in the gentoo penguin (Pygoscelis papua; 35.3ngg-1 wet weight average), followed by the chinstrap (Pygoscelis antarctica; 6.4ngg-1 wet weight average) and Adélie penguins (Pygoscelis adeliae; 12.9ngg-1 wet weight average). Stable isotope analyses (δ15N and δ13C) demonstrated that gentoo feeding and foraging habits differed from those of Adélie and chinstrap penguins. A strong positive correlation was found between PCB concentrations and δ15N, indicating the role of diet on the observed pollutant levels. Porphyrins metabolite levels were also directly correlated with PCB concentrations. These results suggest that PCB levels impair the health of Antarctic penguins.
Asunto(s)
Exposición a Riesgos Ambientales , Compuestos Orgánicos/metabolismo , Porfirinas/metabolismo , Spheniscidae/metabolismo , Animales , Regiones Antárticas , Biomarcadores/metabolismo , Isótopos de Carbono/análisis , Monitoreo del Ambiente , Heces/química , Isótopos de Nitrógeno/análisis , Bifenilos Policlorados/metabolismo , Especificidad de la EspecieRESUMEN
Pulp and paper mill effluents (PPMEs) have been shown to increase gonad size, cause early maturation, and disrupt hormone functions in native and non-native Chilean fish. In this study, we assessed reproductive (plasma vitellogenin; VTG, gonad development) and metabolic (ethoxyresorufin-O-deethylase activity; EROD) end points, relative liver size (LSI) and condition factor (K) of juvenile female and male rainbow trout exposed to effluents. Unlike previous studies, which have focus either on the specific effects of effluent on fish in laboratory exposures or biotic population statuses downstream of discharge sites, we simultaneously assessed the impacts of PPMES on trout using two approaches: (1) laboratory exposures of tertiary treated PPME produced from processing Eucalyptus globulus or Pinus radiata; and (2) in situ bioassay downstream of the combined discharge of the same pulp mill. Despite an increase in the average gonadosomatic index (GSI) in exposed fish, no statistical differences in gonad size between exposed and unexposed individuals was detected. However, both female and male fish exposed to effluents showed significantly higher concentrations of plasma VTG, so more in fish exposed to Eucalyptus-based effluent when compared to Pinus PPME. In addition, male fish showed intersex characteristics in all exposure assays (Eucaliptus and Pinus) and, despite the low concentration of effluent in the river (<1% [v/v]), similar responses were observed in the caged fish. Finally, EROD activity was induced in both in situ exposures and laboratory assays at the higher PPME concentration (60-85% PPME). This study confirms estrogenic effects in Chilean fish exposed to PPME and the necessity for biological effects monitoring in addition to the assessment of physical-chemical endpoints as required in current government regulations.
Asunto(s)
Trastornos del Desarrollo Sexual/inducido químicamente , Eucalyptus/química , Gónadas/efectos de los fármacos , Residuos Industriales , Oncorhynchus mykiss/fisiología , Papel , Pinus/química , Animales , Chile , Citocromo P-450 CYP1A1/metabolismo , Estrógenos , Femenino , Hígado/efectos de los fármacos , Masculino , Reproducción/efectos de los fármacos , Ríos/química , Vitelogeninas/sangre , Contaminantes Químicos del Agua/toxicidadRESUMEN
Sediment constitutes an important sink of endocrine disruptor compounds; however, the potential of sediments to act as a source of endocrine disruptors should be more extensively investigated. The main objective of this study was to determine whether exposure of immature common carp to Uruguay River sediments undergo physiological and endocrine alterations. The lower Uruguay River watershed supports intensive agricultural and forest production, receives municipal sewage discharge and industrial effluent, and a new large pulp mill was constructed in 2006. A 30-day semi-static assay was performed using sediments from four sites along the Uruguay River and compared with an unexposed group in dechlorinated water as a negative control. We focused on two upstream and two downstream sites of a new elemental chlorine free pulp mill. The results showed that plasma vitellogenin levels increased in fish along the river and significant differences were found between the exposed and unexposed groups. Condition factor and gonadosomatic index were not different; however, a significant difference in hepatosomatic index was observed in fish exposed to sediment from an industrial site. A significant reduction in primary spermatocyte accumulation was observed in the exposed group compared with that in the control group, and some individuals exposed to sediments from industrial sites presented with testis-ova. Our results suggest that Uruguay River sediments act as an important source of estrogenic compounds that could be responsible for the alterations observed. Future studies are needed to identify the causal agents and determine exposure routes.
Asunto(s)
Carpas/metabolismo , Disruptores Endocrinos/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química , Ríos/química , Contaminantes Químicos del Agua/análisis , Animales , Disruptores Endocrinos/toxicidad , Femenino , Gónadas/efectos de los fármacos , Masculino , Uruguay , Vitelogeninas/sangre , Contaminantes Químicos del Agua/toxicidadRESUMEN
Responses at low levels of biological organization to evaluate environmental changes and water quality have been used for many years. South America is no different, and recently biochemical endpoints in fish have been used to assess the impacts of industrial and sewage effluents on wild fish populations. For Chilean native freshwater fish, basic biological data is scarce and data on 7-ethoxyresorufin-O-deethylase (EROD) and Acetylcholinesterase (AChE) activity is practically absent. Moreover, extensive variation in these two biochemical endpoints exists among species and seasons. In this article we evaluate seasonal variation in liver EROD and brain AChE activities in Trichomycterus areolatus and Percilia gillissi, two widely distributed native freshwater fish species in central Chile. We observed a marked seasonality in hepatic EROD activity in both species, with maximums for P. gillissi during winter months and sex differences in February, July, August and December. T. areolatus showed no sex differences, and peaks in EROD activity in the middle of summer, winter and late spring. Species differences in EROD activity were observed with activity being 1-2 orders of magnitude higher in P. gillissi compared to T. areolatus. Scarce seasonal variation and no sex related differences in brain AChE for both species were observed. Multivariate analysis (PCA) indicated that physical water quality parameters had some degree of responsibility for the seasonal responses found. The seasonal variability data of these biochemical endpoints were used to optimize study design for future monitoring programs, planning timing of sampling, increasing statistical power by collecting specific sample sizes required.
Asunto(s)
Acetilcolinesterasa/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Monitoreo del Ambiente/normas , Peces/metabolismo , Agua Dulce , Estaciones del Año , Acetilcolinesterasa/análisis , Animales , Encéfalo/metabolismo , Chile , Citocromo P-450 CYP1A1/análisis , Femenino , Hígado/metabolismo , Masculino , Factores SexualesRESUMEN
The Almendares River is the largest river draining the area around Havana City, Cuba. The watershed is heavily populated and industrialized, which has had a significant impact on the flow and water quality of the river. The main goal of this study was to analyze the spatial variability in dietary habits, nutrient flow (using stable isotope ratios δ(15)N and δ(13)C), and mercury (Hg) levels along the Almendares River upstream and downstream of point-source discharges using localized fish Gambusia puncticulata. Stomach contents of G. puncticulata were similar among these sites. However, mean δ(15)N values ranged from 6 to 18 across sites and were lower in fish from downstream than upstream sites, suggesting localized influences of nutrient inputs along the river. δ(13)C values were between -22 and -25 , except at a mid-basin site (-26 to -27), indicating that fish relied on similar carbon sources at most sites. Total mercury concentrations ranged from 0.04 to 0.49 µg/g wet weight whole body and were unrelated to the among-site differences in δ(15)N, but Hg exceeded the threshold considered to be protective of fish health (0.2 µg/g ww whole body) in the majority of fish from all sites but one. Results of this study indicate that although the dietary habits of this species do not vary across sites, tissue differences in δ(15)N, δ(13)C and Hg show little movement of this species among sites. Localized effects of human activities on nutrients and metals may be affecting the health of this species and posing a risk to other consumers in the ecosystem.
Asunto(s)
Tamaño Corporal , Ciprinodontiformes/fisiología , Monitoreo del Ambiente/métodos , Mercurio/análisis , Contaminantes Químicos del Agua/análisis , Animales , Cuba , Ecosistema , Femenino , Contenido Digestivo , Masculino , Ríos/químicaRESUMEN
Few data exist on the possible effects of pulp and paper effluent discharge on native fish populations in the Southern Hemisphere, relative to the research done in the Northern Hemisphere. The present research examined two native fish species (Trichomycterus areolatus and Percilia gillissi) for effects at both the molecular and individual level due to the discharge of effluent from a tertiary treated elemental chlorine-free pulp mill into a fluvial system in Central Chile over three seasons (February 2007, October 2007, January 2008). Different responses were observed between species and between sexes. There was an increase in the production of gonadal 17ß-estradiol in the females of both species but a drop in 11-ketotestosterone production in P. gillissi males. Female gonadal size was increased, especially during the summer period, with corresponding increases the frequency of advanced oocyte development, and in the oocyte diameter in both species. Hepatic ethoxyresorufin-O-deethylase (EROD) activity was elevated for both species downstream of the discharge point, although overall it was higher in P. gillissi than T. areolatus. Decreases in the frequency of smaller-sized fish for both species, as well as a drop in the size of the adults downstream of the discharge point, were observed. The present study is the first evidence of endocrine disruption in native freshwater fish associated with modern pulp mills in South America. This study establishes possible links in the reproductive alterations observed at the subindividual and individual levels that could explain the changes observed at the population level.
Asunto(s)
Bagres/fisiología , Disruptores Endocrinos/toxicidad , Residuos Industriales/efectos adversos , Perciformes/fisiología , Contaminantes Químicos del Agua/toxicidad , Antagonistas de Receptores Androgénicos/toxicidad , Animales , Chile , Citocromo P-450 CYP1A1/metabolismo , Monitoreo del Ambiente , Estradiol/metabolismo , Femenino , Agua Dulce/química , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Hígado/efectos de los fármacos , Masculino , Papel , Densidad de Población , Testosterona/análogos & derivados , Testosterona/metabolismoRESUMEN
The research was carried out to determine whether there are individual-level differences in the bicolor damselfish (Stegastes partitus) within the altered fish communities located on the north coast of Havana, Cuba. There was strong evidence of changes in some morphological and physiological characteristics associated with the impact of land-based pollution in the coastal zone. A combination of impaired recruitment due to habitat degradation with increased food supply due to eutrophication seems to be the best explanation for fishes being heavier and longer at polluted sites. The change in the proportion of color patterns and a very high number of atretic oocytes in the ovaries of fish caught near the mouth of the Almendares River strongly support the idea that not only is the pollution of river waters affecting the marine life in the coastal zone, but also that this pollution has greater effects than the pollution coming from the discharge of Havana Harbor.
Asunto(s)
Oocitos/efectos de los fármacos , Perciformes/crecimiento & desarrollo , Reproducción/efectos de los fármacos , Medición de Riesgo , Contaminantes del Agua/toxicidad , Animales , Ciudades , Cuba , Femenino , Geografía , Oocitos/fisiología , Dinámica Poblacional , Reproducción/fisiología , Ríos/química , Agua de Mar/química , Factores de TiempoRESUMEN
It is difficult to separate effects on fish community assemblages due to anthropogenic stressors from natural factors. We examined small-bodied-fish communities along the northern coast of Cuba near Havana Harbor during the dry (February/March of 2000) and wet (June 2000) seasons. Over 35,000 individual fish were visually counted at 15 sites along the coast in three areas located 0-2.4, 2.4-6.1, and 6.1-10.3 km from the entrance to Havana Harbor. Fish communities in four substrate biotopes did not vary significantly between wet and dry seasons, but did vary with water depth. Proximity to Havana Harbor was the second most important factor affecting fish assemblages, and sites closest to the harbor had reduced populations of the bluehead wrasse (Thalassoma bifasciatum) and an increased abundance of slippery dick (Halichoeres bivittatus). More studies are required at the population and individual levels to link stressors (e.g., contaminants, siltation) directly to observed effects.