Monitoring fish communities in wadeable lowland streams: comparing the efficiency of electrofishing methods at contrasting fish assemblages

Electrofishing is considered a reliable tool to assess the assemblages and biodiversity of fish in wadeable streams. The most widely used electrofishing techniques (point [P], single-pass [S-P], and multiple-pass [M-P]) vary as to the effort needed for sample collection, and this may potentially influence the degree of accuracy. Moreover, little is known about the comparability of the methods and their specific performance in streams with different fish assemblages. The aim of this investigation was to validate (using M-P sampling as reference) the use of P and S-P electrofishing techniques to accurately assess the richness, density and size distribution of fishes in small streams at both regional and global scale independently of fish assemblages and geographical region. We sampled 50-m-long reaches in a total of 33 lowland stream reaches that were located in different climatic and biogeographical regions (Uruguay and Denmark) and hosted different fish assemblages. Subtropical fish communities exhibited higher richness (Uy: 12–32, Dk: 1–9) and densities (Uy: 1.3–5.2, DK: 0.1–4.9 in. m^?2) than temperate streams. We applied both "global models" using the entire database (33 sites) and "local models" including the same number of sites but using the climatic region as a model variable. Regression analyses revealed that the P, S-P and M-P methods all provided an adequate picture of the species composition and size distribution, and transfer equations for comparison between methods are thus not required. Conversely, richness was better predicted by S-P and by P techniques for regional and global models, respectively. Transfer equations obtained for abundance revealed that the P and S-P models can accurately transform catch data into M-P estimations. The transfer equations provided here may have great relevance as they allow relatively reliable comparisons to be made between data obtained by different techniques. We also show that less intensive sampling techniques may be equally useful for monitoring purposes as those requiring more intensive efforts (and costs). We encourage validation of our developed transfer equations on data from other regions of the world.     

Antineoplastic drugs contamination of workplace surfaces in two Portuguese hospitals

Despite the classification as known or suspected human carcinogens, by the International Agency for Research on Cancer, the antineoplastic drugs are extensively used in cancer treatment due to their specificity and efficacy. As human carcinogens, these drugs represent a serious threat to the healthcare workers involved in their preparation and administration. This work aims to contribute to better characterize the occupational exposure of healthcare professionals to antineoplastic drugs, by assessing workplace surfaces contamination of pharmacy and administration units of two Portuguese hospitals. Surface contamination was assessed by the determination of cyclophosphamide, 5-fluorouracil, and paclitaxel. These three drugs were used as surrogate markers for surfaces contamination by cytotoxic drugs. Wipe samples were taken and analyzed by HPLC-DAD. From the total of 327 analyzed samples, in 121 (37 %) was possible to detect and quantify at least one drug. Additionally, 28 samples (8.6 %) indicate contamination by more than one antineoplastic drug, mainly in the administration unit, in both hospitals. Considering the findings in both hospitals, specific measures should be taken, particularly those related with the promotion of good practices and safety procedures and also routine monitoring of surfaces contamination in order to guarantee the appliance of safety measures.     

Toxicity Identification Evaluation (Phase I) of water and sediment samples from a tropical reservoir contaminated with industrial and domestic effluents

The Funil Reservoir (Rio de Janeiro State, Brazil) is an environment degraded by constant discharge of nutrients and pollution coming from the most industrialized region of the country. As a consequence of eutrophication, there are continuous cyanobacteria blooms, which cause acute and chronic toxicity to zooplankton. In this context, Phase I of Toxicity Identification Evaluation (TIE) was performed on Daphnia similis using water and interstitial water from the reservoir, with the aim of identifying classes of compounds responsible for toxicity. The results indicated that water toxicity was due to cyanobacteria resulting from blooms in the reservoir and surfactants. Metals, especially copper, contributed to sediment toxicity. This research is the first attempt to describe the nature of toxicity in this reservoir using this method.     

Towards effective culvert design: monitoring seasonal use and behavior by Mediterranean mesocarnivores

Drainage culverts are known to be used by a diverse number of species. To date, most studies looking at culvert usage have been restricted to the dry season. This seasonal bias has limited our understanding of how different species respond to culverts and, consequently, our ability to find effective ways to promote the use of culverts as aids to species movement. The main goal of this study was to examine the role of highway culverts for mesocarnivores throughout the year. We addressed (1) the seasonality of culvert use, (2) the relative importance of culvert structure, highway features, and surrounding landscape on culvert use, (3) the influence of the water depth and cover on culvert use, and (4) the effect of culvert structure on individual behavior. Fifteen culverts were monitored along 2 highways in southern Portugal using video-surveillance cameras and marble dust for 10 consecutive days per season. We used generalized linear mixed models to determine which factors most affected the culvert use and behavior by mesocarnivores. Our results highlight the effect of seasonality and water on culvert use. Culvert use was positively related with species activity throughout the year. All species (except otters (Lutra lutra)) were less likely to use culverts that contained water more than 3 cm deep or covering more than 70 % of the culvert base. Based on our results, future surveys and culvert retrofit design should address (1) the importance of seasonality in the interpretation of results and (2) the complementarity of culvert-specific features (water, ledges, and naturalization).     

Evaluation of the impacts of road runoff in a Mediterranean reservoir in Portugal

Road runoff is a linear diffuse source of pollution, with very specific characteristics. This study intends to improve the understanding of road runoff impacts in water bodies in Portugal. The chosen case study is S. Domingos reservoir catchment. The study analyzed land uses, the presence of pollution sources, and gathered temporal water quality data and performed site measurements and sample collection. The water quality data for the reservoir was provided by the national water quality monitoring system from the Portuguese Water Institute. The parameters selected were TSS, COD, NO₃ ^?, Cl^?, and Cu. The results obtained revealed that the presence of IP6 highway at S. Domingos catchment affects the water quality; however, the impacts are not significant due to the high dilution effect of the reservoir volume. Agriculture, the main land use of the catchment, is responsible for introducing pollutants such as TSS, Cl^?, COD, N, and P in the local water streams and at the reservoir. TSS, COD, and Cu are pollutants generated by the road. The success of the study was very much dependent on the availability of 12 years of historic water quality data for S. Domingos reservoir, and the use of the moving average method. Taking into consideration the high variability of hydrological variables in Mediterranean climates, the concentration of pollutants in the water bodies must always be assessed in a significant time period.     

Are we headed towards the defaunation of the last large Atlantic Forest remnants? Poaching activities in one of the largest remnants of the Tabuleiro forests in southeastern Brazil

Hunting is a problem to animal conservation in different parts of the world and it has caused the local extinction of several species. The aim of this study was to characterize the poaching activities in one of the main tabuleiro forest remnants of Brazil, the Linhares-Sooretama Block (LSB). Poaching records from 2010 to 2013 were gathered from the agencies responsible for monitoring and combating environmental crimes in the LSB. A total of 693 records (mean = 173 events/year) were collected involving direct (hunted animals, firearms, handmade firearms, traps, poachers, and various hunting supplies) and indirect (tree stands, baits, and poacher signs) evidences of poaching. No differences in the monthly cumulative number of records were found among years, but the distribution of records differed according to the type of evidence. A total of 40 animal seizure events were recorded involving a total of at least 15 taxa directly affected by poaching (reptiles = 2, birds = 6, mammals = 7) and 75 individuals seized (19 individuals/year). Five of the poached species are threatened. Lowland paca (Cuniculus paca) and armadillos were the most poached mammals in the region. Most of the poachers conduct such activities for fun (entertainment) and/or professionally (commercial hunting). The collected data show an approximately 32% increase in the number of poaching events in the region compared with the historical data available for LSB. It may have resulted from a gradual decrease in protection, both in terms of the number of agents deployed and the levels of effort of the teams, which began in 2009. The data demonstrate that poaching is a significant threat to the conservation of the LSB fauna, as it is in other Atlantic Forest remnants and in other regions of the world. Protection activities must be intensified to effectively combat the impacts of poaching in the LSB region, thereby contributing to the conservation of species in one of the few Atlantic Forest remnants whose original species composition still remains intact.     

Cytotoxicity and genotoxicity of Guaribas river water (Piauí, Brazil), influenced by anthropogenic action

In general, tropical rivers have a great impact on human activities. Bioaccumulation of toxins is a worldwide problem nowadays and has been, historically, overlooked by the supervisory authorities. This study evaluated cytogenotoxic effects of Guaribas river (a Brazilian river) water during dry and rainy seasons of 2014 by using the Allium cepa test system. The toxicogenetic variables, including root growth, mitotic index, and chromosomal aberrations, were analyzed in meristematic cells of A. cepa exposed to water samples taken from the up-, within, and downstream of the city Picos (state: Piauí). The physical-chemical parameters were also analyzed to explain water quality and possible anthropogenic action. Additionally, the presence of heavy metals was also analyzed to explain water quality and possible damaging effects on eukaryotic cells. The results suggest that the river water exerted cytotoxic, mutagenic, and genotoxic effects, regardless of the seasons. In addition, Guaribas river presented physico-chemical values outside the Brazilian laws, which can be a characteristic of human pollution (domestic sewage, industrial, and local agriculture). The genetic damage was positively correlated with higher levels of heavy metals. The pollution of the Guaribas river water may link to the chemical contamination, including the action of heavy metals and their impacts on genetic instability in the aquatic ecosystem. In conclusion, necessary steps should be taken into account for further toxicogenetic studies of the Guaribas river water, as it has an influence in human health of the same region of Brazil.     

Activity of the endophytic fungi <Emphasis Type="Italic">Phlebia</Emphasis> sp. and <Emphasis Type="Italic">Paecilomyces formosus</Emphasis> in decolourisation and the reduction of reactive dyes’ cytotoxicity in fish erythrocytes

The current study investigates the potential for discolouration and degradation of Reactive Blue 19 and Reactive Black 5 textile dyes by endophytic fungi Phlebia sp. and Paecilomyces formosus as well as the potential cytotoxicity of products or by-products generated by the treatments in fish erythrocytes. It was observed at 30 days that both endophytes showed biodegradation activity with 0.1 g mL^?1 of dyes. P. formosus showed highest extracellular and intracellular protein content levels after the 15th day, and Phlebia sp. stands out for production of extracellular laccase, indicating that this enzyme may be associated with the decolouration capacity. The dyes showed toxic effects in fishes at 0.01 g mL^?1 concentration, resulting in the appearance of micronuclei in erythrocyte cells. When degraded dyes treated by endophytes were tested, the frequency of micronuclei reduced approximately 20%, indicating the effectiveness of these endophytic in the treatment of textile dyes with less environmental impact, thus indicating a potential for application of these fungi in bioremediation process.     

Cholinesterase characterization in Corbicula fluminea and effects of relevant environmental contaminants: a pesticide (chlorfenvinphos) and a detergent (SDS)

This study characterizes the cholinesterasic forms present in the bivalve Corbicula fluminea, through the analysis of differential affinity towards various substrates and inhibitors. This approach also permitted the validation of cholinesterase inhibition in the mentioned species for monitoring purposes by evaluating the inhibitory activity of a detergent (SDS) and a pesticide (chlorfenvinphos), both in vitro and in vivo. The cholinesterasic form present in the tissues of C. fluminea showed intermediate properties in terms of its relation with substrates and inhibitors. Furthermore, it was not inhibited by the detergent SDS under any of the test conditions, but was clearly inhibited by the selected organophosphate. The data show clearly that the main cholinesterasic form in C. fluminea is responsive to the organophosphate chlorfenvinphos, thus supporting the use of this biomarker for the environmental monitoring of specific contaminants such as anticholinesterasic pesticides. Despite not being commonly attained in the wild, the levels of chlorfenvinphos required to elicit a significant ChE inhibition were only one order of magnitude above actual values of aquatic contamination by this pesticide.     

Characterization of the olfactory impact around a wastewater treatment plant: optimization and validation of a hydrogen sulfide determination procedure based on passive diffusion sampling

A monitoring program based on an indirect method was conducted to assess the approximation of the olfactory impact in several wastewater treatment plants (in the present work, only one is shown). The method uses H2S passive sampling using Palmes-type diffusion tubes impregnated with silver nitrate and fluorometric analysis employing fluorescein mercuric acetate. The analytical procedure was validated in the exposure chamber. Exposure periods ofat least 4 days are recommended. The quantification limit of the procedure is 0.61 ppb for a 5-day sampling, which allows the H2S immission (ground concentration) level to be measured within its low odor threshold, from 0.5 to 300 ppb. Experimental results suggest an exposure time greater than 4 days, while recovery efficiency of the procedure, 93.0+/-1.8%, seems not to depend on the amount of H2S collected by the samplers within their application range. The repeatability, expressed as relative standard deviation, is lower than 7%, which is within the limits normally accepted for this type of sampler. Statistical comparison showed that this procedure and the reference method provide analogous accuracy. The proposed procedure was applied in two experimental campaigns, one intensive and the other extensive, and concentrations within the H2S low odor threshold were quantified at each sampling point. From these results, it can be concluded that the procedure shows good potential for monitoring the olfactory impact around facilities where H2S emissions are dominant.