Degradation of heavy oil by bacteria to decompose organic compounds such as aliphatic and aromatic hydrocarbons has been used in bioremediation. However, the biological and environmental effects of the degradation products including intermediates are still not clear. Here, we monitored the degradation of C-heavy oil by analyzing the products formed in cultures with oil-degrading bacteria (complex microbes or a single bacterial strain). Furthermore, proliferation assays using breast cancer MCF-7 cells and gene-expression profiling of MCF-7 cells using oligonucleotide-DNA microarrays were performed to evaluate the estrogenic activity of the degradation products. While the products did not show any significant cell-proliferative activity, the oil samples cultured for longer periods (2–3 months), whether cultured with mixed microbes or a single bacterial strain, showed gene-expression profiles similar to that of 17β-estradiol (E₂). These results suggest that oil-degradation products have estrogenic activity, and estrogen-like components could possibly be produced during the degradation process.

In this study, three classification techniques (self-organizing maps, hierarchical cluster analysis and discriminant analysis) were applied to identify spatial water pollution levels, temporal water quality response delay phenomena (WQRDP), source pollution types (point, urban non-point, or agricultural non-point). Two models (principal components analysis (PCA), and positive matrix factorization (PMF)) were used to do the further quantitative source apportionment studying. The 27 inflow rivers in spatial were divided into three pollution levels (A, high; B, medium; C, low). The primary pollution pattern in spatial Clusters A, B, and C were point, urban non-point and agricultural non-point separately, in consideration of simultaneous land use types. Source apportionment results identified five typical factors in spatial Cluster A and six typical factors in spatial Cluster B and C as responsible for the data structure, explaining 80%–90% of the total variance of the dataset.

Our knowledge of the concentrations of bioaerosols in residential micro-environments in low income countries is scanty. The present investigation was conducted to assess the culturable concentration and size distribution of bacteria, gram negative bacteria and fungi in two rural and an urban site in Pakistan. The highest indoor culturable bacteria concentration was found at Rural Site II (14,650 CFU/m³) while the outdoor maximum occurred at the urban site (16,416 CFU/m³). With reference to fungi, both indoor and outdoor concentrations were considerably higher at Rural Site I than the other sites. The size distribution of culturable bacteria at all sites showed greater variability than that of culturable fungi. At all sites more than the half (55–93%) of the culturable bacterial and fungal counts were observed in the respirable fraction (<4.7 μm) and so had the potential to penetrate into lower respiratory system.

The effects of radiation on abundance of common birds in Fukushima can be assessed from the effects of radiation in Chernobyl. Abundance of birds was negatively related to radiation, with a significant difference between Fukushima and Chernobyl. Analysis of 14 species common to the two areas revealed a negative effect of radiation on abundance, differing between areas and species. The relationship between abundance and radiation was more strongly negative in Fukushima than in Chernobyl for the same 14 species, demonstrating a negative consequence of radiation for birds immediately after the accident on 11 March 2011 during the main breeding season in March–July, when individuals work close to their maximum sustainable level.

With increasing production of carbon nanoparticles (CNPs), environmental release of these entities becomes an ever-greater inevitability. However, many questions remain regarding their impact on soil microorganisms. This study examined the effects of long or short multiwalled carbon nanotubes (MWCNTs), C60 fullerene and fullerene soot in Gram-negative bacteria. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was applied to derive signature spectral fingerprints of effects. A concentration-dependent response in spectral alterations was observed for each nanoparticle type. Long or short MWCNTs and fullerene soot gave rise to similar alterations to lipids, Amide II and DNA. The extent of alteration varies with nanoparticle size, with smaller short MWCNTs resulting in greater toxicity than long MWCNTs. Fullerene soot was the least toxic. C60 results in the most distinct and largest overall alterations, notably in extensive protein alteration. This work demonstrates a novel approach for assaying and discriminating the effects of CNPs in target systems.

Desorption kinetic and isothermal characteristics of BDE-28 and BDE-47 were investigated using natural soils with different organic carbon fractions. The results indicated that a two-compartment first-order model with dominant contribution of slow desorption could adequately describe the released kinetics of studied PBDEs. Desorption isotherms of different samples could be fitted well by linear distribution model or nonlinear Freundlich model. Moreover, most desorption procedures roughly exhibited hysteresis with respect to preceding sorption ones. At the statistically significant level of 0.05 or 0.1, total organic carbon content (fOC) exhibited significant correlations with the fitted parameters by the isothermal models. The correlations of fOC and SOM fractions (e.g., fulvic acid and humin) with the single point desorption coefficients at lower aqueous concentrations of studied PBDEs were significant; while at higher aqueous concentrations, the relationships were less significant or insignificant. Our findings may facilitate a comprehensive understanding on behaviors of PBDEs in soil systems.

Mechanistic insights into the relative contribution of sorption and biodegradation on the removal of the herbicide isoproturon (IPU) are reported. ¹⁴C-radiorespirometry indicated very low levels of catabolic activity in IPU-undosed and IPU-dosed (0.1, 1, 100 μg L⁻¹) river water (RW) and groundwater (GW) (mineralisation: <2%). In contrast, levels of catabolic activity in IPU-undosed and IPU-dosed river sediment (RS) were significantly higher (mineralisation: 14.5–36.9%). Levels of IPU catabolic competence showed a positive log-linear relationship (r² = 0.768) with IPU concentration present. A threshold IPU concentration of between 0.1 μg L⁻¹ and 1 μg L⁻¹ was required to significantly (p < 0.05) increase levels of catabolic activity. Given the EU Drinking Water Directive limit for a single pesticide in drinking water of <0.1 μg L⁻¹ this result suggests that riverbed sediment infiltration is potentially an appropriate ‘natural’ means of improving water quality in terms of pesticide levels at concentrations that are in keeping with regulatory limits.

The effects of elevated carbon dioxide (CO₂) and nitrogen (N) addition on foliar N and phosphorus (P) stoichiometry were investigated in five native tree species (four non-N₂ fixers and one N₂ fixer) in open-top chambers in southern China from 2005 to 2009. The high foliar N:P ratios induced by high foliar N and low foliar P indicate that plants may be more limited by P than by N. The changes in foliar N:P ratios were largely determined by P dynamics rather than N under both elevated CO₂ and N addition. Foliar N:P ratios in the non-N₂ fixers showed some negative responses to elevated CO₂, while N addition reduced foliar N:P ratios in the N₂ fixer. The results suggest that N addition would facilitate the N₂ fixer rather than the non-N₂ fixers to regulate the stoichiometric balance under elevated CO₂.

High spatial heterogeneity of physical and chemical sediment properties was observed in both horizontal and vertical directions of deposits in a groyne field of the Middle Elbe. The respective sediment cores were less polluted on the top compared to consolidated deeper layers, indicating a decreasing trend of contamination in the river basin. In contrast to water quality monitoring, the impact of the large Elbe flood in 2002 was still visible in the deeper layers (5–30 cm) of the groyne field sediments six years after the event. Due to the fact that the environmental risk increases with erosion potential of discharge and contamination level of sediments, monitoring for environmental risk must capture not only surface sediments but also deeper layers up to an anticipated erosion depth.