Evaluation of disinfection byproducts for their ability to affect mitochondrial function

In the race to deliver clean water to communities through potable water reuse, disinfection and water quality assessment are and will continue to be fundamental factors. There are over 700 disinfection byproducts (DBPs) in water; evaluating each compound is practically impossible and very time consuming. A bioanalytical approach could be an answer to this challenge. In this work, the response of four major classes of DBPs toward mitochondrial membrane potential (ΔΨm) and cytoplasmic adenosine triphosphate (C-ATP) was investigated with human carcinoma (HepG2) cells. Within 90 min of cell exposure, only the haloacetic acid (HAA) mixture caused a cytotoxic response as measured by C-ATP. All four groups (haloacetonitriles (HANs), trihalomethanes (THMs), nitrosamines (NOAs), and HAAs) responded well to ΔΨm, R² > 0.70. Based on the half-maximum concentration that evoked a 50% response in ΔΨm, the response gradient was HANs >> HAAs ∼ THM > NOAs. The inhibition of the ΔΨm by HANs is driven by dibromoacetonitrile (DBAN), while dichloroacetonitrile (DCAN) did not cause a significant change in the ΔΨm at less than 2000 µM. A mixture of HANs exhibited an antagonistic behavior on the ΔΨm compared to individual compounds. If water samples are concentrated to increase HAN concentrations, especially DBAN, then ΔΨm could be used as a biomonitoring tool for DBP toxicity.     

How wave exposure, group size and habitat complexity influence foraging and population densities in fishes of the genus Halichoeres (Perciformes: Labridae) on tropical rocky shores

Wave exposure and habitat complexity have been used to explain variations in the distribution patterns and behavior of many reef fishes. This study analyzed the influence of both factors on density and foraging activity, and the influence of group size on foraging in three species of the genus Halichoeres (Labridae) on tropical rocky shores. It was shown that initial phases (IP) and terminal phases (TP) Halichoeres, were influenced by wave exposure, although foraging in Halichoeres brasiliensis TP was not influenced by wave exposure. The IP in all three species were positively associated with rugosity and algal cover while the TP was positively associated with depth. Habitat complexity also influences foraging in these species. Group size influenced foraging activity, except in H. brasiliensis TP. We also found variations in microhabitat patches used for foraging between species and differences in the stomach contents between species and phases, showing that functional roles change in response to ontogenetic shifts.     

Environmental Surveillance of Polioviruses in Rio de Janeiro,Brazil, in Support to the Activities of Global Polio Eradication Initiative

Wild polioviruses still remain endemic in three countries (Afghanistan, Pakistan, and Nigeria) and re-emergency of wild polio has been reported in previously polio-free countries. Environmental surveillance has been used as a supplementary tool in monitoring the circulation of wild poliovirus (PVs) and/or vaccine-derived PVs even in the absence of acute flaccid paralysis cases. This study aimed to monitor the presence of polioviruses in wastewater samples collected at one wastewater treatment plant located in the municipality of Rio de Janeiro, Brazil. From December 2011 to June 2012 and from September to December 2012, 31 samples were collected and processed. RD and L20B cell cultures were able to isolate PVs and non-polio enteroviruses in 27/31 samples. Polioviruses were isolated in eight samples (type 1 Sabin = 1, type 2 Sabin = 5, and type 3 Sabin = 2). Vaccine-derived polioviruses were not detected nor evidence of recombination with other PVs or non-polio enterovirus serotypes were observed among the isolates. The Sabin-related serotypes 2 and 3 presented nucleotide substitutions in positions associated with the neurovirulent phenotype at the 5′-UTR. Changes in important Amino acid residues at VP1 were also observed in the serotypes 2 and 3. Environmental surveillance has been used successfully in monitoring the circulation of PVs and non-polio enteroviruses and it is of crucial importance in the final stages of the WHO global polio eradication initiative. Our results show the continuous circulation of Sabin-like PVs and non-polio enteroviruses in the analyzed area during the study period.     

Organic speciation of atmospheric particles in Alvão Natural Park (Portugal)

PM₁₀ continental rural background aerosols were collected during a summer field campaign (August–September 2006) at Lamas de Ôlo in the upper zone of the Alvão Natural Park, a mountain region of northern Portugal. In addition to the determination of the carbonaceous content by a thermal–optical method, the organic speciation of aerosols was performed by gas chromatography–mass spectrometry in an effort to evaluate photo-oxidation products of biogenic volatile organic compounds and other markers for source characterization. The detailed analysis revealed relatively high concentrations of polyols and short-chain dicarboxylic, tricarboxylic, hydroxycarboxylic, and oxocarboxylic acids, many of which are thought to be indicators of secondary aerosol formation, accounting for about 70% of global chromatographically resolved mass. Major photo-oxidation products of α- and β-pinene have been detected. The tracers for the photo-oxidation of isoprene comprise two diastereoisomeric 2-methyltetrols, C₅-alkene triols, and 2-methylglyceric acid, which have only recently been elucidated. In addition, the occurrence of levoglucosan and other biomass combustion tracers indicates that the site was affected by wildfires. This source contributed to more than 80% of the organic carbon mass during a period of strong forest fire influence.     

Biochemical changes during the reproductive cycle of the deep-sea decapod <Emphasis Type="Italic">Nephrops norvegicus</Emphasis> on the south coast of Portugal

The objectives of the present study were to characterize the changes in the proximate chemical composition, lipid classes, fatty-acid profiles, glycogen and cholesterol contents of the muscle, ovary and hepatopancreas of Nephrops norvegicus (L.), during the reproduction cycle of this species. The gonadosomatic index increased significantly in May and June and during maturation, suggesting that spawning may start in late spring or summer. The hepatosomatic index also increased throughout the ovarian maturation, suggesting that the hepatopancreatic resources are not depleted. Positive correlations between lipid levels in the ovary and the gonadosomatic index (r=0.51, P<0.05) and the hepatopsomatic index (r=0.27, P<0.05) were found. In fact, ovarian lipid levels increased with maturation, but no concomitant decrease occurred in hepatopancreatic lipids. The muscle showed very low lipid levels (mainly polar lipids), presenting a significant increase during May and June (P<0.05). Higher proportions of neutral lipids, mainly triacylglycerols, were observed in the ovary and the hepatopancreas. Since both ovarian and hepatopancreatic cholesterol increased with maturation, the mobilization of hepatopancreatic cholesterol stores to build up ovarian cholesterol was not clear. On the other hand, protein and glycogen contents in the muscle, ovary and hepatopancreas did not vary as a function of ovary maturity stage. Among the various tissues analysed, the glycogen was mainly stored in the hepatopancreas and to a lesser extent in the muscle. In both ovary and hepatopancreas the major fatty acids were 16:0, 18:1(n-7), 18:1(n-9), 20:5(n-3) and 22:6(n-3), and significant increases (P<0.05) in the levels of monounsaturated and polyunsaturated fatty acids were observed in the ovary during sexual maturation, which indicates these compounds are the major sources of energy during embryonic and early larval development. It was evident that reproduction has profound effects upon the biochemistry of this species, because there are large associated energy costs, owing to the increase in biosynthetic work, which will support the lecithotrophic strategy of the embryos and first larval stages.     

A case study of molinate application in a Portuguese rice field: herbicide dissipation and proposal of a clean-up methodology

This study was designed to monitor molinate losses in surface and underground waters during Ordram application in a rice field situated in central Portugal. Water samples were collected from different sites, before, during and about one month and a half after Ordram application. Molinate quantification was based on a solid-phase microextraction (SPME) method followed by gas chromatography with flame photometric detector (GC-FPD) analysis, and led to the conclusion that the herbicide was dissipated in the environment, reaching levels as high as 3.9 microgl(-1) in underground water and 15.8 microgl(-1) in the river receiving tail waters. The feasibility of the application of treatment methodologies based on adsorption or biodegradation as processes to remove molinate from real-world waters was assessed. These methods seem suitable to reduce molinate concentrations to values in the range of the legally recommended limits (<0.5 microgl(-1)).     

Phosphorus fate and transport in soil columns loaded intermittently with influent of high phosphorus concentrations.

In this study, several columns of different lengths were filled with composite soils sampled from the field at corresponding depths and then loaded intermittently with influent of a high phosphorus concentration to evaluate phosphorus fate and transport in soil. The results indicate that the height of the mass transfer zone, solvent pore velocity, and soil's life expectancy for phosphorus removal increased with depth, while the retained phosphorus per kilogram of soil and the linear adsorption equilibrium coefficient, R, decreased with depth. An equation was developed to link liquid-phase phosphorus with solvent traveling time and soil depth. The results of X-ray diffraction and washout tests indicate that calcium-phosphorus precipitation and/or crystal growth occurred in the columns. The new protocol is useful for evaluation of phosphorus fate and transport in other subsurface systems, because it allows flexible adjustments in hydraulic loadings, feed solution, and sampling schemes.     

Detection,Quantification, and Microbial Risk Assessment of Group A Rotavirus in Rivers from Uruguay

Food and Environmental Virology - The aim of this study was to detect, quantify, and assess the risk of infection and illness for Group A Rotavirus (RVA) in the watersheds of the Santa Lucia and...     

Valuation of natural marine ecosystems: an economic perspective

This paper attempts to examine whether information from valuation studies can help the design of policies adequate to reverse and halt the generally poor state of marine and coastal ecosystems of the Mediterranean and the Black Sea. Economic implications of managing coastal and marine environments are thus discussed by assessing the results of different valuation studies implemented in the area. Lessons and policy recommendations from existing literature are inferred to guide marine resources management decisions. One of our main findings is that there are extremely few published studies within the Mediterranean and Black Sea region which highlights the potential for future research on coastal and marine ecosystems ability to sustain different goods and services as a result of climate change and anthropogenic drivers in the area. However, results reveal that there are substantial positive economic values attached to marketed and non-marketed services provided by marine and coastal ecosystems that justify their sustainable use and management.