Differential blood counting in fish as a non-destructive biomarker of water contamination exposure

Differential white blood cell counting was performed on blood from the fish species Oreochromis niloticus and was used as an in situ indicator of the species’ exposure to contamination. Ten young fish were collected in an area influenced by the discharge of effluents and from a fish farm (control group). The fish were anesthetized and caudal puncture was used to collect the blood. Differential white blood cell counting was performed, as well as the counting of total leukocytes and thrombocytes (in 2000 cells). Physicochemical parameters of the water from both sites were analyzed. The water from the polluted area was found to have high conductivity and low levels of dissolved oxygen, factors that indicate poor environmental quality. Fish collected from the polluted site presented higher percentages of eosinophils and monocytes and fewer thrombocytes because of exposure to pollution and hypoxic conditions. The differential white blood cell count represents a suitable biomarker of environmental health and provides a tool for biomonitoring water quality.     

The determinants mostly disclosed by companies that are members of the Carbon Disclosure Project

Concerns about climate change as a result of anthropic actions have led to an increase in the volume of information disclosed about it in the reports of companies that are members of the Carbon Disclosure Project (CDP). In this context, the factors most disclosed remain obscure due to both the complexity of climate change impacts and the stakeholders’ different interests. This study aims to identify which factors are most disclosed in the reports of companies that are members of CDP. For this purpose, it is necessary to investigate if the factors indicated by managers and experts are the main ones disclosed in the reports of Brazilian companies that are members of CDP, as well as to identify which companies stand out in climate change disclosure based on these factors. To this end, 463 reports submitted by 48 companies between 2014 and 2016 were examined and 32 factors were investigated using the NVivo® software. Some companies submitted reports with unified titles, which reduced the sample. The results indicate that certain factors—prevention of pollution, prevention of loss, management of environmental assets, volume of greenhouse gas (GHG) emissions, and climate change strategy—account for 50.03% of the total volume of information disclosed about climate change. The main lesson learned from this research is that climate change mitigation strategy is strongly supported by the evidence of corporate annual reports, and it has relation with the following determinant factors: pollution prevention, loss prevention, environmental asset management, GHG emissions, and the strategy chosen by the companies to deal with climate change. Due to the low volume of research related to loss prevention and pollution prevention, we have identified that little attention has been paid to these items. Based on our results, we recommend that climate change mitigation strategies begin to consider these determinant factors in their structure because both have a strong influence in demonstrating how companies are managing these factors for stakeholders. Therefore, companies can benefit from this data to manage their resources for the maintenance of the social contract (legitimacy) through the factors most disclosed, especially companies with lower scores on the scale of ranking presented. Hence, stakeholders can have access to more information on strategies that mitigate climate change and help companies improve the disclosure of the actions that contribute to reduction of GHG emissions.     

Determination of gaseous polycyclic aromatic hydrocarbons by a simple direct method using thermal desorption–gas chromatography–mass spectrometry

In the last decade, the development of novel analytical methodologies enabled the identification of several environmental pollutants responsible for health problems associated with indoor exposure. Polycyclic aromatic hydrocarbons (PAHs) are among the potential hazardous chemicals present in ambient air. Due to their bioaccumulation potential and carcinogenic/mutagenic effects, 16 PAHs are currently listed as priority air pollutants. The main goal of this work was to implement a new and simple method for sampling and determination of PAHs in air by using a thermal desorption (TD) technique followed by gas chromatography coupled with mass spectrometry analysis. A detailed study was carried out to optimise the experimental method in each of its phases, including (active) sampling, TD and chromatographic analysis. The results demonstrate that this approach allowed the detection and quantification of the six more volatile PAHs, namely, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, and anthracene. Acceptable precision and good linearity over the explored range were obtained. No carry-over was observed during experimental tests and the method provided a reproducible answer. The applicability of the novel methodology was tested in real environment, namely, on the roof of a building in an urban area, in a domestic kitchen and in a collective car garage. The method enabled the identification of two PAHs in the field samples, specifically, naphthalene (two rings) and phenanthrene (three rings). With regard to PAHs sample composition, the most abundant PAH found, in the three different locations, was naphthalene, accounting for about 84–100 % of the total PAH mass detected.     

Changes in the trade in native medicinal plants in Brazilian public markets

Plants continue to be an important source of new bioactive substances. Brazil is one of the world’s mega-diverse countries, with 20 % of the world’s flora. However, the accelerated destruction of botanically rich ecosystems has contributed to a gradual loss of native medicinal species. In previous study, we have observed a fast and intensive change in trade of medicinal plants in an area of Amazon, where human occupation took place. In this study, we surveyed 15 public markets in different parts of Brazil in search of samples of 40 plants used in traditional medicine and present in first edition of Brazilian Official Pharmacopoeia (FBRAS), published in 1926. Samples of plants commercialized as the same vernacular name as in Pharmacopoeia were acquired and submitted to analysis for authentication. A total of 252 plant samples were purchased, but the laboratory analyses showed that only one-half of the samples (126, 50.2 %) were confirmed as the same plant species so named in FBRAS. The high number of unauthenticated samples demonstrates a loss of knowledge of the original native species. The proximity of the market from areas in which the plant occurs does not guarantee that trade of false samples occurs. The impact of the commerce of the substitute species on their conservation and in public health is worrying. Strategies are necessary to promote the better use and conservation of this rich heritage offered by Brazilian biodiversity.     

Isolation of mesotrione-degrading bacteria from aquatic environments in Brazil

Mesotrione is a benzoylcyclohexane-1,3-dione herbicide that inhibits 4-hydroxyphenyl pyruvate dioxygenase in target plants. Although it has been used since 2000, only a limited number of degrading microorganisms have been reported. Mesotrione-degrading bacteria were selected among strains isolated from Brazilian aquatic environments, located near corn fields treated with this herbicide. Pantoea ananatis was found to rapidly and completely degrade mesotrione. Mesotrione did not serve as a sole C, N, or S source for growth of P. ananatis, and mesotrione catabolism required glucose supplementation to minimal media. LC-MS/MS analyses indicated that mesotrione degradation produced intermediates other than 2-amino-4-methylsulfonyl benzoic acid or 4-methylsulfonyl-2-nitrobenzoic acid, two metabolites previously identified in a mesotrione-degrading Bacillus strain. Since P. ananatis rapidly degraded mesotrione, this strain might be useful for bioremediation purposes.     

Polychlorinated biphenyls and DDT in swordfish (Xiphias gladius) and blue shark (Prionace glauca) from Brazilian coast

The polychlorinated biphenyls (PCBs) and DDT may bioaccumulate in the aquatic food web and have been of great concern due to their toxic effects on wildlife and human health. There is evidence showing that fish in the human diet contributes at a significant proportion to the total intake of PCBs and other organochlorine compounds, particularly fish with higher fat levels. This study investigated the concentration of PCBs and DDTs in muscle tissues of samples of the blue shark (Prionace glauca) and a swordfish (Xiphias gladius) from east Brazilian coast and estimate the human exposure to total DDTs through the consumption of both the species. Samples of the each species were caught between August and September 2001. The mean concentration for summation operator PCBs in P. glauca was 3.15 ng/g w.w. and the summation operator DDTs was 0.93 ng/g w.w. The mean concentration of summation operator PCBs in X. gladius was 6.50 ng/g and the mean of summation operator DDTs was 2.47 ng/g. The estimated daily intake of summation operator DDT through X. gladius or P. glauca consumption can be considered safe since it contributes to less than 0.1% of the limit of acceptable daily intake (ADI) of summation operator DDT proposed by WHO.     

Persistent organic pollutants in atmospheric deposition and biomonitoring with Tillandsia usneoides (L.) in an industrialized area in Rio de Janeiro state, southeast Brazil--Part II: PCB and PAH

Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic bromeliad species as biomonitor and measuring bulk deposition rates of polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH). For the sum of PCB, overall deposition rates were between 17 and 314 ng/(m2 day) in winter and between 43 and 81 ng/(m2 day) in summer, respectively. Deposition rates of dioxin-like PCBs ranged from 0.14 to 2.8 pg WHO-TEQ/(m2 day) in winter and from 0.90 to 4.3 pg WHO-TEQ/(m2 day) in summer. PCB deposition rates (total PCB and WHO-TEQ) were in the same range in winter in V.R. and PNI. In summer, contamination levels in V.R. were 6-10-folds higher than in PNI. PCB concentrations in biomonitor samples from V.R. and PNI were in the same range in summer and in winter. Concentrations of total PCB ranged from 14 to 95 microg/kg dry matter (d.m.) in winter and from 18 to 27 microg/kg d.m. in summer, respectively. The TEQ values were between 1.7 and 4.1 ng WHO-TEQ/kg d.m. in winter and between 1.9 and 2.9 ng WHO-TEQ/kg d.m. in summer. PCB concentrations of di-ortho PCB but not of non-ortho PCB were a factor of 2-4 lower in summer in both areas. PCB congener profiles resembled those from technical formulations. The profiles shifted to the higher chlorinated congeners in summer, probable due to revolatilisation of the lighter components at higher temperatures. PCB profiles in biomonitor resembled those from deposition samples and the shift to the heavier congeners in summer was even more pronounced. PAH deposition rates were in a similar range in both areas (131-2415 ng/(m2 day)). PAH levels in biomonitor samples from V.R. were about one order of magnitude higher than in samples from PNI indicating the impact of local sources. PAH profiles revealed stationary thermal processes as main source of contamination in V.R. whereas in PNI, biomass burning seems to be the main contamination source.     

Heavy metals in untreated/treated urban effluent and sludge from a biological wastewater treatment plant

Background, Aim and Scope

The presence of heavy metals in wastewater is one of the main causes of water and soil pollution. The aim of the present study was to investigate the removal of Cd, Cu, Pb, Hg, Mn, Cr and Zn in urban effluent by a biological wastewater treatment, as well as to quantify the levels of As, Be, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn, Tl, V and Zn in dewatering sludge from the Biological Wastewater Treatment Plant to Ribeirão Preto (RP-BWTP), Brazil.

Materials and Methods

Concentrations of Cd, Cr, Cu, Mn and Pb in wastewater and those of Ni in sludge were determined by atomic absorption spectrophotometry with graphite furnace atomization. Mercury concentrations in wastewater were measured by hydride generation atomic spectrophotometry, and Zn levels were determined by atomic absorption spectrophotometry using acetylene flame. In sludge, the levels of As, Be, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Sn, Tl, V and Zn were determined by inductively coupled plasma-mass spectrometry.

Results

The percentages of removal efficiency (RE) were the following: Hg 61.5%, Cd 60.0%, Zn 44.9%, Cu 44.2%, PB 39.7%, Cr 16,5% and Mn 10.4%. In turn, the mean concentrations (mg/kg) of metals in dewatering sludge followed this increasing order: Tl (<0.03), Hg (0.31), Be (0.43), As (1.14), Cd (1.34), V (59.2), Pb (132.1), Sn (166.1), Cr (195.0), Mn (208.1), Ni (239.4), Cu (391.7), Zn (864.4) and Fe (20537).

Discussion

The relationship between metal levels in untreated wastewater, as well as the removal efficiency are in agreement with previous data from various investigators, It is important to note that metal removal efficiency is not only affected by metal ion species and concentration, but also by other conditions such as operating parameters, physical, chemical, and biological factors.

Conclusions

Metal values recorded for treated wastewater and sludge were within the maximum permitted levels established by the Environmental Sanitation Company (CETESB), São Paulo, Brazil.

Recommendations

There is an urgent need for the authorities who are responsible for legislation on sludge uses in agriculture of establishing safety levels for As, Be, Hg, Sn, Tl and V.

Perspectives

According to the current metal levels, RP-BWTP sludge might be used for agriculture purposes. However, for an environmentally safe use of sewage sludge, further studies including systematic monitoring are recommended. Annual metal concentrations and predicted variations of those elements in the sludge should be monitored.

     

In situ assays with tropical cladocerans to evaluate edge-of-field pesticide runoff toxicity

Tropical regions’ economy is usually based on agriculture, which involves an intensive use, and even frequent overuse, of pesticides. Nevertheless, not much research has been done on the impact of pesticides on tropical aquatic ecosystems, which are often contaminated by runoff-related pesticide inputs due to unpredictable and torrential rainfalls. This study aimed to: (i) adapt and evaluate a short-term sublethal in situ assay using post-exposure feeding as an endpoint, to the tropical cladoceran species Diaphanosoma brachyurum (collected at the Pedra do Cavalo dam in the Paraguaçu River basin, Bahia, Brazil), and, (ii) assess the role of the standard species Daphnia magna as an adequate laboratory surrogate. Lethal and sublethal (post-exposure feeding) responses were assessed for the two species. To evaluate these responses under environmentally realistic exposure conditions, a runoff event was simulated in an agricultural area previously contaminated with different deltamethrin concentrations. The resultant runoff water was used to set up microcosms with different dilutions, simulating the entrance of runoff water in an adjacent lentic system. An in situ assay with D. brachyurum was performed inside the microcosms, allowing to discriminate the effects due to deltamethrin from those due to other potential stressors associated with the experimental design (e.g. organism handling, load of suspended particles, microcosm design). Water samples were collected from microcosms to conduct a laboratory assay with D. magna. The in situ methodologies revealed to be suitable to conduct assays with D. brachyurum under tropical conditions, since all exposed organisms were successfully retrieved from the chambers. Furthermore, none of the potential stressors associated with the experimental design influenced the daphnids’ performance. The tropical cladoceran species, exposed under more realistic conditions, revealed to be more sensitive than the laboratory standard species: lethal effects were only observed for D. brachyurum and sublethal effects were noticed at a lower deltamethrin concentration for this species than for D. magna.     

Pentachlorophenol association with fulvic acids from recycled wastes

The apparent water solubility of pentachlorophenol was measured at pH=6 and at 25 degrees C in pure water, aqueous solutions of three salts (NaCl, KNO(3) and CaCl(2) at 0.010, 0.10 and 1.0M) and in aqueous solutions of three fulvic acids samples extracted from a natural soil (sFA), composted sewage sludge (csFA) and composted livestock's material (lsFA). A solubility enhancement method was developed for the measurement of partition coefficients (K(oc), L/kg organic carbon). Pentachlorophenol associates strongly with the fulvic acid samples and the calculated K(oc) were the following (averages and standard deviations): (sFA) (211+/-22) x 10(2), (csFA) (253+/-26) x 10(2), (lsFA) (235+/-10) x 10(2). For comparison purposes the K(oc) for pyrene were also calculated for the three FA samples and were the following: (sFA) (119+/-10) x 10(2), (csFA) (239+/-21) x 10(2), (lsFA) (92+/-10) x 10(2). The analysis of variance (one-way ANOVA) of the effect of the type of FA sample on the solubilization of pentachlorophenol and pyrene shows that this factor causes significant differences on the aqueous solubilization of these two organic substances.