Comprehensive two-dimensional gas chromatography (GC × GC) utilizing a flow modulator was applied to study particulate polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in the urban atmosphere. Samples were collected onto quartz fiber filters using a PM2.5 sampler at Megacity Shanghai, China. Sample preparation included extraction into n-hexane-dichloromethane mixture and cleanup on silver-impregnated silica column. Analyses were performed well with GC × GC-FID and GC × GC-TOFMS equipment. Average particulate PAHs and n-alkane concentrations were in the range of 40–100 ng/m³and 120–500 pg/m³, respectively. It is alarming to note that PAHs and n-alkane concentrations were increasing with urban PM2.5 values and exceeded the air quality standards in many sampling events. Among them, 2-ring, 3-ring, and 4-ring PAHs accounted for the majority of total PAHs, and C10–15 accounted for the majority of particulate n-alkanes. Potential sources of PAHs in PM2.5 were identified using the diagnostic ratios between PAHs. Local emission sources such as combustion from gasoline and diesel engines were the main contributors of particulate-associated PAHs, while long-range transport had minor contribution to the particulate PAHs. Additionally, we determined the overall carcinogenicity of the samples based on PAH concentrations by a dose addition model and found that the overall carcinogenicity during polluted period was obviously higher than during good air quality period.

Environmental quality indicators are crucial for responsive and cost-effective policies. The objective of the study is to examine the relationship between environmental quality indicators and financial development in Malaysia. For this purpose, the number of environmental quality indicators has been used, i.e., air pollution measured by carbon dioxide emissions, population density per square kilometer of land area, agricultural production measured by cereal production and livestock production, and energy resources considered by energy use and fossil fuel energy consumption, which placed an impact on the financial development of the country. The study used four main financial indicators, i.e., broad money supply (M2), domestic credit provided by the financial sector (DCFS), domestic credit to the private sector (DCPC), and inflation (CPI), which each financial indicator separately estimated with the environmental quality indicators, over a period of 1975–2013. The study used the generalized method of moments (GMM) technique to minimize the simultaneity from the model. The results show that carbon dioxide emissions exert the positive correlation with the M2, DCFC, and DCPC, while there is a negative correlation with the CPI. However, these results have been evaporated from the GMM estimates, where carbon emissions have no significant relationship with any of the four financial indicators in Malaysia. The GMM results show that population density has a negative relationship with the all four financial indicators; however, in case of M2, this relationship is insignificant to explain their result. Cereal production has a positive relationship with the DCPC, while there is a negative relationship with the CPI. Livestock production exerts the positive relationship with the all four financial indicators; however, this relationship with the CPI has a more elastic relationship, while the remaining relationship is less elastic with the three financial indicators in a country. Energy resources comprise energy use and fossil fuel energy consumption, both have distinct results with the financial indicators, as energy demand have a positive and significant relationship with the DCFC, DCPC, and CPI, while fossil fuel energy consumption have a negative relationship with these three financial indicators. The results of the study are of value to both environmentalists and policy makers.

The Three Gorges Project is the largest hydro project in the world, and the water level of the Three Gorges Reservoir (TGR) is dynamic and adjustable with the aim of flood control and electrical power generation. It is necessary to investigate the pollutants and their underlying contamination processes under dynamic water levels to determine their environmental behaviors in the Three Gorges Reservoir Area (TGRA). Here, we report the assessment of organotin compounds (OTs) pollution in the river sediments of the TGRA. Surface sediment samples were collected in the TGRA at low and high water levels. Tributyltin (TBT), triphenyltin (TPhT), and their degradation products in sediments were quantified by gas chromatography-mass spectrometry. Butyltins (BTs) and phenyltins (PhTs) were detected in sediments, and BTs predominated over PhTs in the whole study area under dynamic water level conditions. The concentrations of OTs in sediments varied markedly among locations, and significant concentrations were found in river areas with high levels of boat traffic and wastewater discharge. Sediments at all stations except Cuntan were lightly contaminated with TBT, and total organic carbon (TOC) was a significant factor affecting the fate of TBT in the TGRA. The butyltin and phenyltin degradation indices showed no recent inputs of TBT or TPhT into this region, with the exception of fresh TPhT input at Xiakou Town. Shipping activity, wastewater discharge, and agriculture are the most likely sources of OTs in the TGRA.

Mitigation of petroleum hydrocarbons was investigated during a 5-month greenhouse experiment, to assess the rhizoremediation (RR) potential in sediments with different characteristics colonized by Juncus maritimus, a salt marsh plant commonly found in temperate estuaries. Furthermore, the efficiency of two bioremediation treatments namely biostimulation (BS) by the addition of nutrients, and bioaugmentation (BA) by addition of indigenous microorganisms, was tested in combination with RR. The effect of the distinct treatments on hydrocarbon degradation, root biomass weight, and bacterial community structure was assessed. Our result showed higher potential for hydrocarbon degradation (evaluated by total petroleum hydrocarbon analysis) in coarse rhizosediments with low organic matter (OM), than rhizosediments with high OM, and small size particles. Moreover, the bacterial community structure was shaped according to the rhizosediment characteristics, highlighting the importance of specific microbe-particle associations to define the structure of rhizospheric bacterial communities, rather than external factors, such as hydrocarbon contamination or the applied treatments. The potential for hydrocarbon RR seems to depend on root system development and bacterial diversity, since biodegradation efficiencies were positively related with these two parameters. Treatments with higher root biomass, and concomitantly with higher bacterial diversity yielded higher hydrocarbon degradation. Moreover, BS and BA did not enhance hydrocarbons RR. In fact, it was observed that higher nutrient availability might interfere with root growth and negatively influence hydrocarbon degradation performance. Therefore, our results suggested that to conduct appropriate hydrocarbon bioremediation strategies, the effect of sediment characteristics on root growth/exploration should be taken into consideration, a feature not explored in previous studies. Furthermore, strategies aiming for the recovery of bacterial diversity after oil spills may improve the efficiency of hydrocarbon biodegradation in contaminated salt marsh sediments.

Due to the nature of the phosphorus (P) removal mechanisms associated with constructed wetlands, the sustainability of P treatment is usually of high interest. As a result, a 4-year dataset from a typical multi-celled integrated constructed wetland (ICW) located at Glaslough in Co. Monaghan, Ireland was evaluated to determine the effects of long-term P loadings and hydrological inputs on P treatment. The ICW was intensively monitored year-round from February 2008 through March 2012 for total P and molybdate reactive phosphate (MRP). Domestic wastewater was loaded at 16.4 ± 0.96 g m² year⁻¹ for total P and 11.2 ± 0.74 g m² year⁻¹ for MRP. Average mass reductions over the monitoring period were 91.4 and 90.1 %, respectively. The area-based kinetic coefficients (K ₍₂₀₎) of 11.8 for total P and 15.6 m year⁻¹ for MRP indicated a high area-specific retention rate. The ICW appeared to have a sustained capacity for P adsorption and retention, but the treatment was influenced mainly by external hydrological inputs and fluctuations in wastewater loadings. Linear regression analyses showed a reduction in mass retention of both total P and MRP with increased effluent flow volumes. Monthly mass reductions exceeded 90 % when the effluent flow volumes were less than 200 m³ day⁻¹. When monthly effluent flow volumes exceeded 200 m³ day⁻¹, nonetheless, mass reductions became highly variable. Designs and management of ICW systems should adopt measures to limit external hydrological loadings in order to maintain sufficient P treatment.

Nanotechnology has revolutionized the world through introduction of a unique class of materials and consumer products in many arenas. It has led to production of innovative materials and devices. Despite of their unique advantages and applications in domestic and industrial sectors, use of materials with dimensions in nanometers has raised the issue of safety for workers, consumers, and human environment. Because of their small size and other unique characteristics, nanoparticles have ability to harm human and wildlife by interacting through various mechanisms. We have reviewed the characteristics of nanoparticles which form the basis of their toxicity. This paper also reviews possible routes of exposure of nanoparticles to human body. Dermal contact, inhalation, and ingestion have been discussed in detail. As very limited data is available for long-term human exposures, there is a pressing need to develop the methods which can determine short and long-term effects of nanoparticles on human and environment. We also discuss in brief the strategies which can help to control human exposures to toxic nanoparticles. We have outlined the current status of toxicological studies dealing with nanoparticles, accomplishments, weaknesses, and future challenges.

In the current study, a mechanical dispersion method was employed to separate clay (<2 μm), silt (2–20 μm), and sand (20–50 μm) fraction in six bulk soils. Batch equilibrium method was used to conduct atrazine sorption and desorption experiments on soil organo-mineral fractions with bulk soils and their contrasting size fractions separately. The potential contribution of total organic carbon (TOC) for atrazine retention in different fractions was further investigated. It was found that clay fraction had the highest adsorption but the least desorption capacities for atrazine, while sand fraction had the lowest adsorption but the highest desorption capacities for atrazine. The adsorption percentage of atrazine, as compared with adsorption by the corresponding bulk soils, ranged from 53.6 to 80.5 %, 35.7 to 56.4 %, and 0.2 to 4.5 % on the clay, silt, and sand fractions, respectively. TOC was one of the key factors affecting atrazine retention in soils, with the exact contribution dependent on varying degree of coating with mineral component in different soil size fractions. The current study may be useful to predict the bioavailability of atrazine in different soil size fractions.

The Santos and São Vicente Estuary has suffered extensively over the years from irregular industrial deposits. The present study aimed to evaluate liver disease prevalence and potential associated risk factors in four of the Estuary’s areas (Pilões and Água-Fria, Cubatão Center, Continental São Vicente, and Guarujá) and a reference area (Bertioga). This study consisted of a cross-sectional study design, in which a questionnaire was used to collect information in 820 households at each of the study areas. The proportion of total liver diseases, hepatitis, cirrhosis, and cancer (liver, biliary tract, and pancreas) per area were estimated. Pearson’s chi-square test and two proportion differences test were applied in order to evaluate associations between disease occurrence and areas and to test differences between two proportions, respectively. Single and multiple logistic regression models were applied to assess associations between disease prevalence and the different study areas. Liver disease prevalence was 1.5 % among all inhabitants and 1.4 % among those without any type of exposure. Among those who reported the presence of liver disease, a higher percentage of the participants that reported hepatitis (27.7 %) or other liver disease (48.7 %) did not report occupational or alcohol exposures. Hepatitis (77.8 %) was the most reported disease, and a statistical association between living in Pilões and Água-Fria and the occurrence of hepatitis was observed (Pearson’s χ ²: z = 18.1; p = 0.001). The consumption of locally-produced groceries (2.88; CI: 1.24–6.70) and water (5.88; CI: 2.24–15.45) were shown to be risk factors for the occurrence of liver disease. Thus, environmental exposure is still a public health problem present in the estuary region.

The hexane and ether extracts of leaves, bark and roots of Jatropha curcas were screened for their toxicity against different developmental stages of housefly. The larvicidal, pupicidal and adulticidal activities were analysed at various concentrations (0.78–7.86 mg/cm²) of hexane and ether extracts. The lethal concentration values (LC₅₀) of hexane extract of J. curcas leaves were 3.0 and 0.27 mg/cm² for adult and larval stages of housefly, respectively, after 48 h. Similarly, the ether extract of leaf showed the LC₅₀ of 2.20 and 4.53 mg/cm² for adult and larval stages of housefly. Least toxicity was observed with hexane root extract of J. curcas with LC₅₀ values of 14.18 and 14.26 mg/cm² for adult and larvae of housefly, respectively, after 48 h. The variation in LC₅₀ against housefly pupae was found to be 8.88–13.10 mg/cm² at various J. curcas extract concentrations. The GC-MS analysis of J. curcas leaf extract revealed the presence of trans-phytol (60.81 %), squalene (28.58 %), phytol (2.52 %) and nonadecanone (1.06 %) as major components that could be attributed for insecticidal activity of J. curcas extracts.

The Voltri Massif is an ophiolitic complex located in the Ligurian Alps close to the city of Genova (Northern Italy) where several springs discharge high pH (up to 11.7), low salinity waters produced by the active serpentinization of the ultramafic basement. Mixing of these hyperalkaline waters with the river waters along with the uptake of atmospheric carbon dioxide forms brownish carbonate precipitates covering the bedrock at the springs. Diverse archaeal and bacterial communities were detected in these carbonate precipitates using 454 pyrosequencing analyses of 16S ribosomal RNA (rRNA) genes. Archaeal communities were dominated by members of potential methane-producing and/or methane-oxidizing Methanobacteriales and Methanosarcinales (Euryarchaeota) together with ammonia-oxidizing Nitrososphaerales (Thaumarchaeota) similar to those found in other serpentinization-driven submarine and terrestrial ecosystems. Bacterial communities consisted of members of the Proteobacteria, Actinobacteria, Planctomycetes, Bacteroidetes, Chloroflexi, and Verrucomicrobia phyla, altogether accounting for 92.2 % of total retrieved bacterial 16S rRNA gene sequences. Amongst Bacteria, potential chemolithotrophy was mainly associated with Alpha- and Betaproteobacteria classes, including nitrogen-fixing, methane-oxidizing or hydrogen-oxidizing representatives of the genera Azospirillum, Methylosinus, and Hydrogenophaga/‘Serpentinomonas’, respectively. Besides, potential chemoorganotrophy was attributed mainly to representatives of Actinobacteria and Planctomycetales phyla. The reported 16S rRNA gene data strongly suggested that hydrogen, methane, and nitrogen-based chemolithotrophy can sustain growth of the microbial communities inhabiting the carbonate precipitates in the hyperalkaline springs of the Voltri Massif, similarly to what was previously observed in other serpentinite-hosted ecosystems.