Cannabis sativa L. and Brassica juncea L. grown on arsenic-contaminated industrial soil: potentiality and limitation for phytoremediation

Environmental Science and Pollution Research - Phytoremediation represents a natural method to remove contaminants from soil. The goal of this study was to investigate the potential of...     

Umbelliferone ameliorates ulcerative colitis induced by acetic acid via modulation of TLR4/NF-κB-p65/iNOS and SIRT1/PPARγ signaling pathways in rats

Environmental Science and Pollution Research - Ulcerative colitis (UC) is a common chronic, idiopathic inflammatory bowel disease associated with inflammatory perturbation and oxidative stress....     

Festering food: chytridiomycete pathogen reduces quality of Daphnia host as a food resource

When parasitic infections are severe or highly prevalent among prey, a significant component of the predator's diet may consist of parasitized hosts. However, despite the ubiquity of parasites in most food webs, comparisons of the nutritional quality of prey as a function of infection status are largely absent. We measured the nutritional consequences of chytridiomycete infections in Daphnia, which achieve high prevalence in lake ecosystems (>80%), and tested the hypothesis that Daphnia pulicaria infected with Polycaryum laeve are diminished in food quality relative to uninfected hosts. Compared with uninfected adults, infected individuals were smaller, contained less nitrogen and phosphorus, and were lower in several important fatty acids. Infected zooplankton had significantly shorter carapace lengths (8%) and lower mass (8-20%) than uninfected individuals. Parasitized animals contained significantly less phosphorus (16-18% less by dry mass) and nitrogen (4-6% less) than did healthy individuals. Infected individuals also contained 26-34% less saturated fatty acid and 31-42% less docosahexaenoic acid, an essential fatty acid that is typically low in cladocera, but critical to fish growth. Our results suggest that naturally occurring levels of chytrid infections in D. pulicaria populations reduce the quality of food available to secondary consumers, including planktivorous fishes, with potentially important effects for lake food webs.     

Assessment of arsenic level in the hair of the nonoccupational Egyptian population: pilot study.

Arsenic level of hair samples of apparently healthy Egyptian was measured by means of hydride atomic absorption spectrophotometery. It ranged between 0.04 and 1.04 mg As/kg hair, about 55% of the analysed hair samples were within the range of allowable values (0.08-0.25 mg As/kg hair), but 45% were not. There were no considerable sex-related differences (0.303 and 0.292 mg As/kg hair for males and females, respectively). Different educational levels did not influence it either, when the effect of the age had been excluded. Children and adolescents proved to be more susceptible to arsenic as their mean levels (0.353 microg/g), and were significantly higher than those in the adults (0.233 microg/g). Smoking and some dietary habits had an important role in the elevation of arsenic levels among the nonoccupational Egyptian population: 60% of smokers and 66.7% of indoor passive smokers had arsenic levels >0.25 mg As/kg hair. Arsenic levels were also dependent on the kind of smoking, as hair arsenic of the subject smoking molasses tobacco was found to be significantly higher than that of cigarette smokers (0.459 and 0.209 mg As/kg hair, respectively). The frequency of meat and fish consumption per week was also found to be positively, significantly correlated with arsenic levels. On the other hand, the frequency of consumption of fruits, fresh and cooked vegetables, milk and milk products per week beneficially influenced the arsenic level of the hair samples examined. Arsenic content of the consumed water in Egypt was 0.001 mg/l, which is below the maximum drinking water level allowed by World Health Organisation (WHO). Therefore, the arsenic content of domestic tap water hardly contributed to the arsenic exposure of the Egyptian population in the regions of the study. It is likely that exposure routes by smoking, fish and animal protein consumption are the principal cause of arsenic accumulation in the general Egyptian population.     

A Regional Classification Scheme for Estimating Reference Water Quality in Streams Using Land-Use-Adjusted Spatial Regression-Tree Analysis

Various approaches are used to subdivide large areas into regions containing streams that have similar reference or background water quality and that respond similarly to different factors. For many applications, such as establishing reference conditions, it is preferable to use physical characteristics that are not affected by human activities to delineate these regions. However, most approaches, such as ecoregion classifications, rely on land use to delineate regions or have difficulties compensating for the effects of land use. Land use not only directly affects water quality, but it is often correlated with the factors used to define the regions. In this article, we describe modifications to SPARTA (spatial regression-tree analysis), a relatively new approach applied to water-quality and environmental characteristic data to delineate zones with similar factors affecting water quality. In this modified approach, land-use-adjusted (residualized) water quality and environmental characteristics are computed for each site. Regression-tree analysis is applied to the residualized data to determine the most statistically important environmental characteristics describing the distribution of a specific water-quality constituent. Geographic information for small basins throughout the study area is then used to subdivide the area into relatively homogeneous environmental water-quality zones. For each zone, commonly used approaches are subsequently used to define its reference water quality and how its water quality responds to changes in land use. SPARTA is used to delineate zones of similar reference concentrations of total phosphorus and suspended sediment throughout the upper Midwestern part of the United States.     

Kinetics and thermodynamic studies of Methyl Orange removal by polyvinylidene fluoride-PEDOT mats

We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0–10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.     

Characterization of acute toxicity,genotoxicity, and oxidative stress of dimethoate in Rhinella arenarum larvae

Environmental Science and Pollution Research - There is a great concern worldwide about the global decline of amphibians, particularly by agrochemical pollution. The aim of this study was to assess...     

Status of electronic waste recycling techniques: a review

Environmental Science and Pollution Research - The increasing use of electrical and electronic equipment leads to a huge generation of electronic waste (e-waste). It is the fastest growing waste...