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To evaluate the physiological state of the wild fish inhabiting the Biobío River in South-Central Chile, susceptible to the chemical contamination from different sources, biochemical and physiological biomarkers were applied to wild fish Percilia irwini and Trichomycterus areolatus in situ. Fish caught in the Biobío river in low, medium, and high anthropic impacts areas, with different pollution degrees along the river. Ethoxyresorufin O-O deethylase (EROD) activity was evaluated in fish liver. Length, weight, Gonad weight and Liver weight, Physiological Index, and gill and liver histopathology were conducted. Physicochemical parameters (pH, Temperature, Conductivity, and TDS) were measured at each sampling site. The results indicated a deteriorating condition in the biological parameters of both species in a high anthropic zone. Fishes show an increase in physiological indices and EROD liver activity, agreeing with previous studies supporting evidence of reproductive change development as we move downstream the river. Also, an increase in histopathological lesions towards the lower third stretch of the Biobío River. The Integrated Index of Physiological Biomarkers (IPBR) indicated that sites located in the high impact area (P. irwini: BC: 4.09; RC: 3.38; PC: 3.50; SJ: 2.34 and T. areolatus BC: 6.06, PC: 5.37; SJ: 5.42) have the most detrimental environmental quality, compared to reference area. The integrated biomarker analysis demonstrates that the alterations observed are related to the high anthropic activity levels downstream from the sites with the least intervention, demonstrating that the IPBR used is a complementary tool for studies of the Environmental Effects Monitoring approach.

PBDEs (10 congeners) were analyzed using GC-MS in superficial sediments and organisms of the Concepción Bay after the 2010 Tsunami. From all congeners analyzed PBDE-47, -99, -100 and -209 were the most frequently detected. Concentrations (ngg(-1) d.w.) in sediments for ΣPBDE-47, -99, -100 were low (0.02-0.09). However, PBDE-209 showed significantly higher values ∼20ngg(-1) d.w. This result were ∼10 times lower than those reported in a previous study of the 2010 Tsunami. The high result might be influenced by the massive urban debris dragged by the 2010 Tsunami. In organisms, concentrations of PBDE-47, -99, -100 (∼0.4ngg(-1) d.w.) were higher than those found in sediments (∼0.04ngg(-1) d.w.). Differences in PBDE pattern were also observed between different levels of the trophic food chain (primary and secondary consumers). This is the first attempt to assess the current status of Concepción Bay after the 2010 Tsunami., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Current monitoring programs are focused on hydrophobic chemicals detection in aquatic systems, which require the collection of high volumes of water samples at a given time. The present study documents the preliminary use of the polymer ethylene vinyl acetate (EVA) as a passive sampler for the detection of a hydrophobic chemical used by salmon industries such as cypermethrin. Initially, an experimental calibration in laboratory was performed to determine the cypermethrin equilibrium between sampler and aquatic medium, which was reached after seven days of exposure. A logarithm of partitioning coefficient EVA-water (logKEVA-W) of 5.6 was reported. Field deployment of EVA samplers demonstrated average concentrations of cypermethrin in water to be 2.07 ± 0.7 ng L(-)(1) close to salmon cages, while near-shore was 4.39 ± 0.8 ng L(-)(1). This was a first approach for assessing EVA samplers design as a tool of monitoring in water for areas with salmon farming activity., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

To add data on trace metal contamination of Humboldt penguins in the South Pacific, levels of trace metals (As, Hg, Pb, Cu, Zn, and Cd) and porphyrins (copro-, uro-, and proto-) in excreta of Humboldt penguins that inhabit some important nesting sites on the northern coast of Chile were determined. Fresh excreta were collected on Pan de Azúcar Island, Chañaral Island, and Cachagua Island, from December 2011 to January 2012. Concentration of metals was determined by flame atomic absorption spectrophotometry, whereas porphyrins levels were measured by fluorimetric analysis. Concentrations (dry weight) of Cu (199.67 μg g(-1)), As (7.85 μg g(-1)), and Pb (12.78 μg g(-1)) were higher (p ≤ 0.05) in Cachagua Island. Colonies from Pan de Azúcar Island showed the highest levels of Hg (0.76 μg g(-1)), Cd (47.70 μg g(-1)), and Zn (487.10 μg g(-1)). Samples from Cachagua Island showed the highest (p ≤ 0.05) levels of copro- (2.16 nmol g(-1)), uro- (2.20 nmol g(-1)), and protoporphyrins (2.23 nmol g(-1)). There was a positive correlation between the metals As, Pb, and Cu with uro-, copro-, and protoporphyrins. The results indicated that penguin colonies from Cachagua Island are more exposed to metal contamination than penguin colonies from Pan de Azúcar and Chañaral Islands, thus being more likely to develop certain diseases caused by contamination with metals. Considering biomagnification, the metals detected in the excreta of Humboldt penguins can be a source of contamination from marine environments to terrestrial ecosystems, which could also affect other living organisms.

Fifty-five biota samples from the Coast of Concepcion (Chile) were analyzed for PBDEs, emerging brominated FRs, halogenated norbornenes and naturally-occurring MeO-PBDEs. PBDEs, MeO-PBDEs and halogenated norbornenes were detected at concentration levels ranging from 11 to 170, nd to 118 and nd to 5.8 ng/g lw, respectively. However, emerging brominated FRs such as decabromodiphenylethane (DBDPE), hexabromobenzene (HBB) and pentabromoethylbenzene (PBEB) were not detected in any sample. Bioaccumulation and bioconcentration processes were evaluated for the different families of compounds. Biomagnification factors (BMFs) were calculated, and some PBDE congeners (BDE-28, BDE-183 and BDE-209) as well as MeO-PBDEs presented BMF>1, being values of the naturally occurring MeO-PBDEs higher than those obtained for PBDEs. As regards halogenated norbornenes, BMF<1 were found., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The Lenga Estuary is one of the most industrialized sites in south central Chile where the historic operation of chlor-alkali plants resulted in large quantities of mercury (Hg) being deposited into the estuary. This historical contamination may still represent a risk to the biota in the estuary. To investigate this four macroinvertebrates, Neotrypaea uncinata (ghostshrimp), Elminius kingii (barnacle), Hemigrapsus crenulatus (shore crab) and Perinereis gualpensis (ragworm) were collected seasonally from three different sites in the Lenga Estuary and one in a reference estuary (Tubul Estuary), and analyzed for Hg and stable isotopes (δ(15)N and δ(13)C). Mercury concentrations in Lenga sediments ranged from 0.4 ± 0.1 to 13 ± 3 mg/kg, while those in Tubul sediments ranged from 0.02 ± 0.01 to 0.07 ± 0.09 mg/kg. Total Hg concentrations of invertebrates were significantly different between estuaries (p<0.05), but not by species or season for each estuary (p>0.05). In contrast, organic Hg concentrations were different by species and season with shore crab muscle tissues exhibiting the greatest percent difference. Site-specific relationships demonstrated that total Hg concentrations in ragworm best reflected the total Hg sediment mercury concentrations. Signatures of δ(13)C were correlated to the organic Hg % rather than total Hg. This suggests that organic Hg concentrations in these species were related to the carbon sources., (Copyright © 2012 Elsevier B.V. All rights reserved.)

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., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This work aimed to study biochemical biomarkers and population responses in the polychaete Perinereis gualpensis (Nereididae) from two Chilean estuaries, Lenga (36°45'S; 73°10'W) and Tubul-Raqui (37°14'S,73°26'W). Lenga estuary is characterized by high mercury and PAH levels as consequence of several historic incidental spills while Tubul is mainly impacted by intensive fish activity. Raqui estuary, with low anthropogenic impact was considered the reference site. Worms were collected in winter and summer periods and tissues were differentiated between anterior (first 40 segments) and posterior region (the rest of the body). Levels of the antioxidant glutathione (GSH), glutathione-S-transferase (GST) activity, total antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (TBARS) levels, Na+, K+-ATPase activity (NKA) and metalothioneins (MTs) content were determined in each region. L3 (combined length of prostomiun+peristomiun+first segment) length, size, frequency, histograms and density of individuals were studied in all sites and seasons. Significant differences (p<0.05) were observed among sites for most of the biochemical responses (GSH, GCL, GST, ACAP and TBARS), showing variation between seasons and body regions. Population responses in the most polluted estuary (Lenga) showed differences in size, frequency, lengths and low densities compared with lower impacted sites, indicating the costs associated with tolerance in organisms chronically exposed to estuarine pollution., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A tiered framework provides a structured approach to assess and manage risk and underpins much of the legislation concerning chemicals and environmental management. Management decisions regarding appropriate controls can have high cost implications to the regulated community. The risk framework provides an evidence-based approach to reduce uncertainty in decision making. Traditional assessment is heavily dependent on laboratory-generated toxicity test data and estimations of exposure and effect. Despite many well documented demonstrations of in situ methodologies, they are rarely used by regulators to help improve assessment or to validate risk. Emerging legislation puts greater emphasis on environmental outcomes and represents a significant shift from the reliance on chemical measures alone toward biological responses that improve assessment and demonstrate ecological benefit. Diagnostic methods, that could include in situ-based measures, will help assess and manage environments failing to achieve good status and it is likely that a weight of evidence approach will be needed to help inform management decisions. The potential application of such measures in the risk framework is reviewed in the context of current and emerging legislation concerning chemicals. Effect measures on the basis of in situ methods provide an alternative line of evidence and can help reduce uncertainty in decision making. Criteria are presented to help select appropriate methods in a multiple-line, weight of evidence approach.

Caging experiments were conducted using hatchery-reared, immature, female rainbow trout (Oncorhynchus mykiss) in three previously defined areas of the Biobio River (south central Chile) representing a pollution gradient from the pulp and paper mill discharges area: a pre-impact area (upstream area, reference location), an impact area (area directly influenced), and a postimpact area (downstream area, less influenced). No significant changes were observed in the physiological index as represented by condition factor (K) and liver somatic index during different sampling times (after 11, 21, and 30 d of exposure). Ethoxyresorufin-O-deethylase activities were significantly higher in trout caged at the impact and postimpact discharges areas (two- to fourfold) compared with the reference (pre-impact) area, and a strong inhibition of acetylcholinesterase activity, reaching 50%, was observed mainly in fish caged at the impact area. A significant endocrine-disrupting effect (reproductive level) was evidenced by significant increments in gonad somatic index and plasma vitellogenin levels combined with an induction of gonad maturation (presence of vitellogenic oocytes) in trout caged at the impact and postimpact areas. These results, generated by an in situ approach, confirmed our group's findings for trout exposed to sediment in the laboratory: discharges of pulp mill effluent in the Biobio River are associated with the effects evaluated at different biological levels.

Semi-volatile organochlorine compounds (OC) were analyzed in remote Andean soils and lake sediments. The sampling sites covered a wide latitudinal gradient from 18 degrees S to 46 degrees S along Chile and an altitudinal gradient (10-4500 m). The concentrations were in the order of background levels, involving absence of major pollution sources in the high mountain areas. Significant correlations were found between log-transformed concentrations of hexachlorobenzene, alpha- and gamma-hexachlorocyclohexane in soils and total organic content (TOC). In addition, TOC-normalized concentrations of the most volatile OC showed a significant linear dependence with air temperature. This good agreement points to temperature as a significant factor for the retention of long range transported OC in remote ecosystems such as the Andean mountains, although other variables should not be totally excluded. The highest concentrations of OCs were achieved in the sites located at highest altitude and lowest temperature of the dataset.

Residues of five pesticides in surface water were surveyed during 2001 and 2003 in the Traiguen river basin in Southern Chile. Simazine, hexazinone, 2,4-D, picloram herbicides and carbendazim fungicide were selected through a pesticide risk classification index. Six sampling stations along the river were set up based on agricultural and forestry land use. The water sampling was carried out before and after the pesticide application periods and in correspondence to some rain events. Pesticides were analyzed by HPLC with DAD detection in a multiresidue analysis. During 2001, in the first sampling campaign (March), the highest concentrations of pesticides were 3.0 microg l(-1) for simazine and hexazinone and 1.8 microg l(-1) for carbendazim. In the second sampling (September), the highest concentration were 9.7 microg l(-1) for 2,4-D, 0.3 microg l(-1) for picloram and 0.4 microg l(-1) for carbendazim. In the last sampling period (December), samples indicated contamination with carbendazim fungicide at levels of up to 1.2 microg l(-1). In sampling carried out on May 2003, no pesticides were detected. In October 2003, the highest concentrations of pesticides were 4.5 microg l(-1) for carbendazim and 2.9 microg l(-1) for 2,4-D. Data are discussed in function of land use and application periods of the products, showing a clear seasonal pattern pollution in the Traiguen river. Risk assessment for these pesticides was calculated by using a risk quotient (RQ = PNEC/PEC). For picloram the calculated RQ < was 0, which indicates that no adverse effects may occur due to the exposure to this herbicide in the Traiguen river basin. For 2,4-D, simazine, hexazinone, carbendazim RQ > 1, meaning that adverse effects could occur and it is necessary to reduce pesticide exposure in surface waters. It is recommended to continue with a pesticide monitoring program and the implementation of ecotoxicological testing with local and standardized species in order to consider the probability of effects occurrence, with less uncertainty. Thus, it will be more feasible to make some recommendations to regulatory agencies regarding the pesticide use.

The aim of this work is to increase the information on trace metals in seabirds and coastal soils in the Antarctica. Concentrations (mg kg dry weight) of Cd, Cu, Cr, Ni, Mn, Zn and Pb were determined by ICP-MS in fresh excreta and feathers of Gentoo penguins as well as in soils around the nesting sites where this species inhabits. Samples were collected in four locations throughout the Antarctic Peninsula (January 2014): O'Higgins Base, Stranger Point, Neko Harbor and Doumer Island. The highest levels of elements were found in excreta from O'Higgins Base (2.92, 266.83, 2.99, 44.75, 18.15, 1.68 and 317.92 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively) and Stranger Point (1.97, 222.51, 2.98, 36.62, 13.41, 1.46 and 201.18 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively. Similarly, the highest levels were found in feathers from O'Higgins Base (0.21, 20.89, 1.44, 1.19, 5.90, 0.63 and 64.07 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively) and Stranger Point (0.14, 19.65, 1.47, 1.23, 3.85, 0.60 and 64.19 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively). In soils, the highest levels were found in O'Higgins Base (4.31, 421.94, 64.75, 404.76, 28.13, 281.54 and 484.99 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively), whereas the lowest levels were found in Neko Harbor and Doumer Island. These results observed could be related to the major human presence in the northern area of the Antarctic Peninsula and large-scale transport of pollutants. The metals detected in the excreta of the Gentoo penguin can contribute to increase the contamination of coastal terrestrial ecosystems, which could also affect other living organisms. [ABSTRACT FROM AUTHOR]

As protection of the natural reproductive pattern is necessary to ensure adequate conservation of natural populations, we examined some typical reproductive endpoints throughout a reproductive season in two Chilean species that lack this baseline information. Trichomycterus areolatus and Percilia gillissi both have maximum gonad development for an austral spring spawning period beginning in October/November. Trichomycterus areolatus appears to spawn many times, as there was no significant correlation between gonad size and body size, a characteristic of asynchronous spawners. Percilia gillissi appears to be a multiple spawner, with larger individuals spawning into January, although most fish completed spawning by December. To design a study for monitoring purposes with these species, the best sampling periods would be late fall (June) and spring (October) for P. gillissi, as power analysis indicated a target sample size of 20 females in June and 34 in October; the sample size in October could be reduced to 12 by selecting females > 50 mm in length, thereby reducing the variability. Trichomycterus areolatus gonadal variability was much higher, requiring a sample size in excess of 80 individuals for adequate statistical power. An understanding of these basic reproductive and metabolic patterns in South American freshwater fishes will help ensure better management of the water resources. [ABSTRACT FROM PUBLISHER]

Environmental monitoring activities in Chile are relatively new and have traditionally relied on physicochemical measurements. The pulp mill industry in Chile is highly competitive in the global market and several new large mills have recently opened. Early studies on fish in the receiving environments revealed lower species richness and an increase in the abundance of introduced species relative to native ones near pulp mill discharges. Even though changes were observed, their relationship with the discharges was unclear. Several difficulties related to small body sizes and the unavailability of basic biological data for native Chilean fish species were found during initial field studies. One of the main challenges is the standardization of monitoring methods (including fish species selection, sampling sizes, indicators, reference sites, etc.) and consensus about the responses that should be considered in a river monitoring program in the Chilean context. This paper summarizes major findings from a series of studies looking at impacts on fish at different levels of biological organization and the current approach used in Chile for monitoring impacts of pulp mill effluents on wild fish populations. [ABSTRACT FROM AUTHOR]

The Chillán River in Central Chile plays a fundamental role in local society, as a source of irrigation and drinking water, and as a sink for urban wastewater. In order to characterize the spatial and temporal variability of surface water quality in the watershed, a Water Quality Index (WQI) was calculated from nine physicochemical parameters, periodically measured at 18 sampling sites (January–November 2000). The results indicated a good water quality in the upper and middle parts of the watershed. Downstream of the City of Chillán, water quality conditions were critical during the dry season, mainly due to the effects of the urban wastewater discharge. On the basis of the results from a Principal Component Analysis (PCA), modifications were introduced into the original WQI to reduce the costs associated with its implementation. WQIDIR2 and WQIDIR, which are both based on a laboratory analysis (Chemical Oxygen Demand) and three (pH, temperature and conductivity), respectively, four field measurements (pH, temperature, conductivity and Dissolved Oxygen), adequately reproduce the most important spatial and temporal variations observed with the original index. They are proposed as useful tools for monitoring global water quality trends in this and other, similar agricultural watersheds in the Chilean Central Valley. Possibilities and limitations for the application of the used methodology to watersheds in other parts of the world are discussed. [ABSTRACT FROM AUTHOR]