The roles of verapamil (VRP), a calcium channel blocker, on cadmium-induced physiological stress in freshwater teleost Oncorhynchus mykiss were investigated in this study. Forty-eight juvenile rainbow trout were divided randomly into four groups, i.e., control group, VRP group (100 μg/L VRP), Cd group (50 μg/L Cd2+), and VRP + Cd group (100 μg/L VRP + 50 μg/L Cd2+). After 1-week exposure, oxidative stress indices (lipid peroxidation and carbonyl protein) and antioxidant parameters (superoxide dismutase, glutathione reductase, glutathione peroxidase, and reduced glutathione) were measured in gill and liver of all tested fish. Additionally, the behavioral changes were recorded during the experimental period. Compared with the control, cadmium-induced stress was apparent as reflected by a serious oxidative stress in gill and liver tissues, inhibited branchial antioxidant parameters, and induced hepatic antioxidant responses, as well as abnormal behaviors observed. In the VRP + Cd group, the antioxidant defense system of fish returned to the control level, and the fish behavioral abnormalism markedly decreased. The present results suggested that VRP could reduce the cadmium-induced physiological stress in rainbow trout and provided further evidence that Cd2+ uptake through Ca2+ transport pathways in freshwater teleost.

As one of the important problems in global change, elevated ultraviolet-B (UV-B) radiation induced by the depletion of stratospheric ozone layer has received more and more attentions around the world. Field experiment with barley was conducted to investigate the effects of elevated UV-B radiation on microbial biomass carbon and nitrogen in rhizosphere and nonrhizosphere soil. The experiment was designed with two UV-B radiation levels, i.e., elevated (E, simulating 25% stratospheric ozone depletion) and ambient (A, control), and performed at the Station of Agricultural Meteorology, Nanjing University of Information Science and Technology, Nanjing, China. Compared with the control, elevated UV-B radiation significantly depressed shoot biomass by 13.2–42.6% and root biomass by approximately 50% from jointing to ripening stage. Elevated UV-B radiation significantly increased microbial biomass C and N in nonrhizosphere soil in most cases, but significantly decreased microbial biomass C and N in rhizosphere soil. Further researches are needed to elucidate whether the above findings are connected with the changes in composition and amount of root exudates induced by elevated UV-B radiation, which can mainly affect the dynamics of soil microbial biomass.

Aldama dentata Llave & Lex. is a plant native to Latin America that exhibits metallicolous populations. Its ecophysiological (EP) response to Cu stress, administered as graded soil concentrations (Cs) of the fungicide copper(II) oxychloride, is examined in depth. Using a systems biology- and population dynamics-inspired approach, an r/K-driven model is proposed that satisfactorily explains the plant Cu concentration (Cp) versus Cs EP response curves for the root, shoot, and whole plant. A. dentata was found to be a Cu excluder (ME). The dual role of Cu as a nutrient and toxin at low and high concentrations, respectively, manifested as a parabolic variation of the foliar area where the toxicity appeared as a second-order effect. The power-law variance of biomass (Bp) with Cp expected from the universal allometric scaling law of biology was loosely followed and is discussed in terms of the mode of Cu uptake by the plant and Cu’s dual physiological role. Biometric growth indices reflected the impact of Cu on the photosynthetic energy harvest. The general applicability of the r/K-driven model was corroborated by its successful application to the published Cp–Cs data of the well-known Cu ME, Silene vulgaris. The r–K factors suggest a new quantitative manner of comparing the phytoavailability of the metal and the plant’s accumulation capability across soil types. A. dentata with high root Cp but low Bp diminution could potentially find use as a Cu phytostabilizer.

Total topsoil 50th percentile Cu, Pb and Zn concentrations (n = 491) in the Sydney estuary catchment were 23 μg g−1, 60 μg g−1 and 108 μg g−1, respectively. Nine percent, 6% and 25% of samples were above soil quality guidelines, respectively and mean enrichment was 14, 35 and 29 times above background, respectively. Soils in the south-eastern region of the catchment exhibited highest metal concentrations. The close relationship between soil metal and road network distributions and outcomes of vehicular emissions modelling, strongly suggested vehicular traffic was the primary source of metals to catchment soils. Catchment soil and road dust probably make an important contribution to contamination of the adjacent estuary. The concentration of soil metals followed the land use trend: industrial > urban > undeveloped areas. A high proportion (mean 45%, 62% and 42%, for Cu, Pb and Zn, respectively) of metals in the soils may be bioavailable.

The influence of the operational variables on the Anammox process has been generally researched considering each variable separately. However, the optimization of the process also requires the identification of the more significant variables and their possible interactions. Response surface models were successfully applied to evaluate the performance of the Anammox process in a deammonification system (i.e., one-stage biofilm Anammox process) taking into account the combined effects caused by two sets of three variables. Specific Anammox activity was measured by a manometric method and used as the response variable. The obtained models pointed out that the significant variables were the temperature, the value of pH, and the ratio between the unionized species of the substrates (free ammonia and free nitrous acid (FA/FNA)). There were interactions among them caused by chemical equilibriums. Total nitrogen concentration and ammonium concentration were found to be not significant in the tested range. According to the models, the optimum values of temperature, pH, and free ammonia to free nitrous acid ratio within the test ranges were, respectively, 30°C, 7.0, and 0.3. Further research at higher temperatures and lower values of pH and FA/FNA ratios would be necessary in order to find the absolute optimum conditions for the process. The obtained model can be also useful in order to develop control strategies that take into account the significant variables and their optimum ranges. A strategy to control deammonification reactors has been proposed, according to the results of the modeling.

The goal of the present work was to increase our knowledge on the behavior of manganese and nickel in soil within a Mediterranean environment. The study assessed the concentration levels of Mn and Ni (heavy metals selected for their essential role in the development of plants) in 250 soil horizon samples within 125 soil profiles of undisturbed soils in La Rioja (Spain). The study was undertaken to investigate and predict Mn and Ni concentrations on a regional scale. The analysis of spatial distribution of the elements was found to be affected by the nature of bedrock and, to a lesser extent, the anthropogenic origin. The variation of vertical distributions can be related, first, to natural sources—mainly the bed rocks—and, second, to soil processes. The geographical distribution of soil Mn is important to agriculture, nutrition, and health. Soil Mn and Ni maps of the area were elaborated, using geostatistics and geographic information systems. Mapping of geographical distributions will be useful in future research to determine regional patterns of Mn and Ni bioavailability, Mn and Ni deficiencies, and the possible consequences of land disposal of Mn- and Ni-laden wastes.

Biological degradation rates of six pharmaceuticals and personal care products were examined in soil from a land application site and in adjacent soil with no prior history of effluent exposure. Microbial degradation rates were compared over 2 weeks under standing water or saturated conditions and draining conditions after having been saturated for 3 days. Biological degradation of 17β-estradiol exhibited rapid rates of biological degradation under both saturated and draining conditions. Half-lives for 17β-estradiol ranged from 1.5 to 4 days; 66–97% was lost from the soils. Estriol showed a pattern of biological degradation in both saturated and draining conditions though the half-lives were longer (8.7–25.9 days) than those observed for 17β-estradiol. Twenty-eight percent to 73% of estriol was lost over the 14 days treatment period. Estrone and 17α-ethinylestradiol exhibited slower rates of biological transformation under saturated and draining conditions. Half-lives for estrone ranged between 27.5 and 56.8 days with loss of at most 21%. 17α-ethinylestradiol exhibited half-lives of 22.6–207 days. Half-life data for ibuprofen ranged from 30.4 to 1,706.4 days in this experiment. Losses of up to 17% were observed in draining soils. Triclosan loss was at most 10%, and half-lives were 70.9–398.8 days. In all cases, soils that were draining from saturated conditions exhibited faster degradation rates than soils that remained saturated. Prior exposure of the soil to effluent did not always result in higher biological degradation rates.

In recent years, Microcystis bloom occurs frequently and causes a wide range of social, environmental, and economic problems. In this study, dose-dependent inhibitory effect of cinnamaldehyde on the growth of Microcystis aeruginosa was investigated. It was found that cinnamaldehyde with the concentration more than 0.6 mM showed algicide activity against M. aeruginosa. When M. aeruginosa was exposed to 0.6 mM cinnamaldehyde, considerable reactive oxygen species (ROS) were generated followed by lipid peroxidation and decrease in the content of both chlorophyll a and soluble protein. Although superoxide dismutase had made response to the stress caused by cinnamaldehyde, activity increasing after a time of lag could not prevent the lysis of M. aeruginosa cells. Interestingly, the addition of antioxidants glutathione and L-ascorbic acid (Vc) could prevent the lysis of M. aeruginosa cells. All the results suggested that cinnamaldehyde induced the death of M. aeruginosa cells via inducing ROS burst. Further understanding of the mechanism of cinnamaldehyde-induced M. aeruginosa cell death would contribute to the control of cyanobacteria pollution.

In a warming climate, mercury (Hg) pathways in the Arctic can be expected to be affected. The Hg transport from the high arctic Zackenberg River Basin was assessed in 2009 in order to describe and estimate the mercury transported from land to the marine environment. A total of 95 water samples were acquired and filtered (0.4 μm pore size), and Hg concentrations were determined in both the filtered water and in the sediment. A range of other elements were also measured in the water samples. Hg concentrations in the filtered water were in general highest in the beginning of the season when the water came mainly from melted snow. THg concentrations in the sediment were in general relatively constant or slightly decreasing until mid-August, where after the concentrations increased. A principal component analysis separated the samples into spring, summer and autumn samples indicating seasonal characteristics of the patterns of element concentrations. The total amount of Hg in the sediment transported was estimated to 2.6 kg. Approximately 60% of the sediment-transported Hg occurred during a 24-h flood in the beginning of August caused by a glacial lake outburst flood. The total amount of transported dissolved Hg was estimated to 46 g, and 13% of this transport occurred during the 24-h flood. If it is assumed that the Hg transport by Zackenberg River is representative for the general glacial rivers in East Greenland, the total Hg transport into the North Atlantic from Greenland alone is approximately 4.6 tons year−1 with an estimated annual freshwater discharge of ∼440 km3.

The aggregate potential health impact due to ambient volatile organic compounds on the population living in the area nearby the petrochemical industrial complex in Thailand was evaluated using measured air contaminants concentration. Airborne volatile organic compounds were collected using canisters and were analyzed by gas chromatography/mass spectrophotometer following the US.EPA TO 15 procedure. Composite samples taken over a 24-h period were collected monthly. Concentrations of volatile organic compounds (VOCs) were analyzed for a suite of 24 compounds covering both carcinogenic and non-carcinogenic substances. Results were determined and analyzed in order to evaluate their spatial variability and their potential health risk. Comparison of data from each monitoring site indicated that patterns of VOCs across sites were different from their major species and their concentrations which might be influenced by nearest potential emission sources. Carcinogenic VOCs such as benzene, 1,3butadiene, and 1,2 dichloroethane were found to be higher than their annual national standards. A potential cancer risk map was drawn based on benzene concentration in order to illustrate the zone of impact and the number in the population likely to be exposed. Results indicated that 82% of the total area, and 89.6% of the total population were within the impact area. It was suspected that high concentrations of benzene and 1,3 butadiene might be attributed by both the mobile source and the point source of emissions while 1,2 dichloroethane was suspected to be emitted from factories located upwind from the monitoring sites. Hazard quotients and hazard indexes were applied to determine chronic health effects with non-cancer endpoints. Calculated values of hazard indexes for each of the target organ systems were lower than 1, which indicated that the non-cancer chronic risk due to level of volatile organic compounds in the study area was less.