Sediment cores from 12 Chinese lakes were analyzed to investigate the historical inputs of polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE) during the past few decades. Concentrations of ΣPBDE₁ (sum of tri- to hepta-BDEs), ΣPBDE₂ (sum of nona- to deca-BDEs) and DBDPE in the surface sediments were 0.02–0.29 ng g⁻¹, 0.46–46.6 ng g⁻¹ and 1.02–3.64 ng g⁻¹, respectively. The temporal trends of PBDEs and DBDPE followed a general increase from the bottom to the surface. The calculated fluxes for ΣPBDE₁, ΣPBDE₂ and DBDPE were 0.001–0.09, 0.03–4.24, and 0.05–0.31 ng cm⁻² yr⁻¹, and the inventories were 0.09–7.86, 0.91–461, and 3.83–24.6 ng cm⁻², respectively. The urbanization and industrialization are highly related to the contamination of PBDEs and DBDPE in sediments. The DBDPE input in recent years was still lower than ΣPBDE₂ but the temporal trends indicated that the contamination would increase with the increasing usage of DBDPE in the future.

This study provides a combined dataset on N loss pathways and fluxes from sloping cropland in the purple soil area, southwestern China. A lysimeter experiment was conducted to quantify nitrate leaching (May 2004–May 2010) and N₂O emission (May 2009–May 2010) losses. Nitrate leaching was the dominant N loss pathway and annual leaching fluxes ranged from 19.2 to 53.4 kg N ha⁻¹, with significant differences between individual observation years (P < 0.05). Direct N₂O emissions due to N fertilizer use were 1.72 ± 0.34 kg N ha⁻¹ yr⁻¹, which corresponds to an emission factor of 0.58 ± 0.12%. However, indirect N₂O emissions caused by nitrate leaching and surface runoff N losses, may contribute another 0.15–0.42 kg N ha⁻¹ yr⁻¹. Our study shows that nitrate leaching lowered direct N₂O emissions, highlighting the importance for a better understanding of the tradeoff between direct and indirect N₂O emissions for the development of meaningful N₂O emission strategies.

To assess the potential contribution of nitric oxide (NO) emission from the plants grown under the increasing nitrogen (N) deposition to atmospheric NO budget, the effects of simulated N deposition on NO emission and various leaf traits (e.g., specific leaf area, leaf N concentration, net photosynthetic rate, etc.) were investigated in 79 plant species classified by 13 plant functional groups. Simulated N deposition induced the significant increase of NO emission from most functional groups, especially from conifer, gymnosperm and C₃ herb. Moreover, the change rate of NO emission was significantly correlated with the change rate of various leaf traits. We conclude that the plants grown under atmospheric N deposition, especially in conifer, gymnosperm and C₃ herb, should be taken into account as an important biological source of NO and potentially contribute to atmospheric NO budget.

This paper addresses the effects of gaseous nitric acid (HNO₃) and ozone (O₃), two important air pollutants, on six lichen species with different morphological, ecological, and biological characteristics. The treatment chambers were set up in a factorial design consisting of control chambers, chambers fumigated with HNO₃, with O₃, and with HNO₃ and O₃, together. Each species showed a different sensitivity to the fumigations, reflecting the physiological variation among species. Our results clearly indicate that HNO₃ is a strong phytotoxin to many lichens, and that O₃ alone has little effect on the measured parameters. The combined fumigation effects of HNO₃ and O₃ were not significantly different from HNO₃ alone.

Ofloxacin (OFL) was used as a model antibiotic and the quenching of OFL fluorescence by DOM was examined with an emphasis on temperature-dependent quenching kinetics. OFL fluorescence intensity was corrected for inner filter and temperature effects. The kinetics data were fitted well using a two-compartment pseudo first-order kinetics model. Three quenching compartments were identified using this model, namely, a very fast quenching compartment (q₀) and two pseudo first-order quenching compartments (q₁ + q₂). The q₀ values had a positive relationship with temperature, while (q₁ + q₂) were negatively related with temperature. In addition, OFL–DOM binding quantified by (q₁ + q₂) was consistent with binding result obtained from dialysis equilibrium system. We concluded that q₀ was resulted from dynamic quenching, while (q₁ + q₂) was attributed to static quenching. The dynamic quenching of OFL by DOM accounted for 30–90% to the overall quenching and thus was very significant.

Surveying toxicity of complex geochemical media as aquatic sediments often yields results that are either difficult to interpret or even contradictory to acknowledged theory. Multi-level biomarkers were investigated in a benthic fish exposed to estuarine sediments through laboratory and in situ bioassays, to evaluate their employment either in ecological risk assessment or in more mechanistic approaches to assess sediment-bound toxicity. Biomarkers reflecting lesions (such as genotoxicity or histopathology), regardless of their low or absent specificity to contaminants, are efficient in segregating exposure to contaminated from uncontaminated sediments even when classical biomarkers like CYP1A and metallothionein induction are inconclusive. Conversely, proteomics and gene transcription analyses provided information on the mechanics of toxicity and aided explaining response variation as a function of metabolic imbalance and impairment of defences against insult. In situ bioassays, although less expedite and more affected by confounding factors, produced data better correlated to overall sediment contamination.

Sixteen soil samples were collected from the central Tibetan Plateau (CTP). The soil concentrations of polybrominated diphenyl ethers (PBDEs) in CTP were analyzed. The detected 42 congeners were divided into light, intermediate and heavy fractions. In addition to the various minerals, other soil properties were also characterized, including the content of soil organic carbon (SOC) and the particle size distribution. The clay content is positively related to the intermediate fraction of the PBDEs and negatively related to the light and heavy fractions. Similar correlations were observed for SOC and the fine-particle fraction (size < 2 μm). The coefficient of determination (r²) associated with a linear regression indicated that the clays were more highly correlated with the fractional pattern of the PBDEs than with the other properties, such as SOC and the fine-particle fraction. The values of r² between clays and three fractions of PBDEs are 0.70, 0.69 and 0.58.

This study is a first attempt to investigate the impact of urban contamination on metal tolerance of heterotrophic river biofilms using a short-term test based on β-glucosidase activity. Tolerance levels to Cu, Cd, Zn, Ni and Pb were evaluated for biofilms collected at three sites along an urban gradient in the Seine river (France). Metallic pollution increased along the river, but concentrations remained low compared to environmental quality standards. Biofilm metal tolerance increased downstream from the urban area. Multivariate analysis confirmed the correlation between tolerance and contamination and between multi-metallic and physico-chemical gradients. Therefore, tolerance levels have to be interpreted in relation to the whole chemical and physical characteristics and not solely metal exposure. We conclude that community tolerance is a sensitive biological response to urban pressure and that mixtures of contaminants at levels lower than quality standards might have a significant impact on periphytic communities.

Mercury loads in tropical estuaries are largely controlled by the rainfall regime that may cause biodilution due to increased amounts of organic matter (both live and non-living) in the system. Top predators, as Trichiurus lepturus, reflect the changing mercury bioavailability situations in their muscle tissues. In this work two variables [fish weight (g) and monthly total rainfall (mm)] are presented as being important predictors of total mercury concentration (T-Hg) in fish muscle. These important explanatory variables were identified by a Weibull Regression model, which best fit the dataset. A predictive model using readily available variables as rainfall is important, and can be applied for human and ecological health assessments and decisions. The main contribution will be to further protect vulnerable groups as pregnant women and children. Nature conservation directives could also improve by considering monitoring sample designs that include this hypothesis, helping to establish complete and detailed mercury contamination scenarios.

Psychotropic substances were monitored in eight big cities of Italy over one year, starting in May 2010, in the frame of the Ariadrugs Project. Yearly average concentrations ranged from 0.02 ± 0.01 to 0.26 ± 0.11 ng/m³ for cocaine, from 0.05 ± 0.05 to 0.96 ± 1.37 ng/m³ for cannabinoids, from 16 ± 6 to 61 ± 28 ng/m³ for nicotine, and from 1.0 ± 0.8 to 8 ± 7 ng/m³ for caffeine. Palermo and Turin were the cities suffering the lowest and the highest psychotropic substance concentrations, respectively. Nicotine and cocaine exhibited trends less seasonally modulated than common air toxicants. Caffeine and cannabinoids peaked in winter dropping close to zero from May to August. In Rome, where various anthropic contours were investigated in February 2011, differences were observed both in net concentrations and ratios of psychotropic substances vs. regulated toxicants. Ambient drugs look as a consequence of addiction and their burdens give insights about the corresponding consumes.