Carbon nanotubes (CNT) are strong sorbents for organic micropollutants, but changing environmental conditions may alter the distribution and bioavailability of the sorbed substances. Therefore, we investigated the effect of green algae (Chlorella vulgaris) on sorption of a model pollutant (diuron, synonyms: 3-(3,4-Dichlorophenyl)-1,1-dimethylurea, DCMU) to CNT (multi-walled purified, industrial grade, pristine, and oxidized; reference material: Diesel soot). In absence of algae, diuron sorption to CNT was fast, strong, and nonlinear (Freundlich coefficients: 105.79–106.24 μg/kgCNT·(μg/L)−n and 0.62–0.70 for KF and n, respectively). Adding algae to equilibrated diuron-CNT mixtures led to 15–20% (median) diuron re-dissolution. The relatively high amorphous carbon content slowed down ad-/desorption to/from the high energy sorption sites for both industrial grade CNT and soot. The results suggest that diuron binds readily, but – particularly in presence of algae – partially reversibly to CNT, which is of relevance for environmental exposure and risk assessment.

Pharmaceutical compounds (PCs) are introduced into agricultural soils via irrigation with treated wastewater (TWW). Our data show that carbamazepine, lamotrigine, caffeine, metoprolol, sulfamethoxazole and sildenafil are persistent in soils when introduced via TWW. However, other PCs, namely diclofenac, ibuprofen, bezafibrate, gemfibrozil and naproxen were not detected in soils when introduced via TWW. This is likely due to rapid degradation as confirmed in our microcosm studies where they exhibited half-lives (t1/2) between 0.2–9.5 days when soils were spiked at 50 ng/g soil and between 3 and 68 days when soils were spiked at 5000 ng/g soil. The degradation rate and extent of PCs observed in microcosm studies were similar in soils that had been previously irrigated with TWW or fresh water. This suggests that pre-exposure of the soils to PCs via irrigation with TWW does not enhance their biodegradation. This suggests that PCs are probably degraded in soils via co-metabolism.

The traditional way to study Sources–Receptor Relationships (SRRs) of wet deposition is based on sensitivity simulation, which has weakness in dealing with the non-linear secondary formation pollutants (e.g. ozone and nitrate). An on-line source tracking method has been developed in the Nested Air Quality Prediction Modeling System (NAQPMS) coupled with cloud-process module for the first time. The new model can not only quantify the total volume of the sulfate, nitrate and ammonium wet deposition with more accuracy, but also trace these acidic species to their emitted precursors. Compared with previous studies, our result clearly shows: (1) East China and Central China, which are the two primary export regions, have 15–30% and 10% effect on wet deposition in other areas, respectively; (2) Besides the above two regions, the total acid deposition in Southwestern and Northeastern China have reached or exceeded the critical loads under their own environmental conditions.

We studied the bonding and release kinetics of Cd, Cu and Pb from different soils in the older metropolitan area of Copenhagen. Total Cd, Cu and Pb concentrations were elevated 5–27 times in the urban soils compared to an agricultural reference soil, with Cd and Pb in mainly mobilisable pools and Cu in strongly bound pools. The soils were subjected to accelerated leaching studies in Ca(NO3)2 or HNO3 solutions resulting in release up to 78, 18 and 15% of total Cd, Cu and Pb soil concentrations over a period of 15 weeks. The relative initial Cd and Pb release rates increased 10 fold when pH decreased 2 and 3 units, respectively, while increases in Cu release rates were only seen at pH below 4. The total leachable Cu and Pb pools were higher in urban soils compared the agricultural reference soil but not for Cd.

This study aimed to assess the recovery capacity of the freshwater bivalve Corbicula fluminea subjected to industrial metal discharges (Cd, Zn). After a 24-day exposure in a metal-contaminated river, bivalves were transferred and maintained in the laboratory for one year under metal-free conditions. Metal accumulation, metallothionein production and genetic expressions of genes involved in metal stress were studied. Results demonstrated the high persistence of Cd in tissues (only 73% eliminated after 365 days) whereas Zn was rapidly depurated. The Cd half-life was estimated around 240 days. Metallothioneins were strongly induced within the 28 first days of decontamination, then decreased by 45% after 365 days. The metal exposure of bivalves led to a significant gene induction. After 28 days, most of the genes were no longer overexpressed, suggesting that the bivalves may withstand small amounts of non-essential metals in their tissues without showing signs of detrimental effects on the tested genes.

Polybrominated Diphenyl Ethers (PBDEs) are ubiquitous in the indoor environment owing to their use in consumer products and various studies around the world have found higher concentrations indoors than outdoors. Central air conditioner (A/C) systems have been widely used in many workplaces, therefore, studying of PBDEs in central A/C filter dust is useful to better understand the occurrences and health implications of PBDEs in indoor environments. The present study examined the occurrence of PBDEs in central A/C filter dust collected from various workplaces (n = 20) in Thessaloniki, Greece. The sum concentrations of 21 target congeners (∑21PBDE) in A/C dust ranged between 84 and 4062 ng g−1 with a median value of 1092 ng g−1, while BDE-209 was found to be the most abundant BDE congener. The daily intake via dust ingestion of PBDEs estimated for the employees of the occupational settings ranged from 3 to 45 ng day−1 (median 12 ng day−1).

We observed that at a contamination level of 4.25 mg-atrazine/kg-soil, the biota–soil accumulation factor (BSAF) for the anecic M. guillelmi is approximately 5 times that for the epigeic E. foetida. This is attributable to the fact that bio-uptake by E. foetida is mainly through dermal absorption, whereas bio-uptake by M. guillelmi is largely affected by the gut processes, through which the physical grinding and surfactant-like materials facilitate the desorption of atrazine from soil. Strikingly, biochar amendment resulted in much greater reduction in BSAF for M. guillelmi than for E. foetida. At a biochar dose of 0.5% (wt:wt) the difference in BSAF between the two species became much smaller, and at a dose of 2% no statistical difference was observed. A likely explanation is that gut processes by M. guillelmi were much less effective in extracting atrazine from the biochar (the predominant phase wherein atrazine resided) than from soil particles.

Pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs) enter the soil environment via irrigation with treated wastewater, groundwater recharge, and land application of biosolids. The transformation and fate of PPCP/EDCs in soil affects their potential for plant uptake and groundwater pollution. This study examined four PPCP/EDCs (bisphenol A, diclofenac, naproxen, and 4-nonylphenol) in soil by using 14C-labeling and analyzing mineralization, extractable residue, bound residue, and formation of transformation products. At the end of 112 d of incubation, the majority of 14C-naproxen and 14C-diclofenac was mineralized to 14CO2, while a majority of 14C-bisphenol A and 14Cnonylphenol was converted to bound residue. After 112 d, the estimated half-lives of the parent compounds were only 1.4–5.4 d. However a variety of transformation products were found and several for bisphenol A and diclofenac were identified, suggesting the need to consider degradation intermediates in soils impacted by PPCP/EDCs.

We investigated effects of arsenate (AsV), chromate (CrVI) and sulfate on As and Cr uptake and translocation by arsenic hyperaccumulator Pteris vittata (PV), which was exposed to AsV, CrVI and sulfate at 0, 0.05, 0.25 or 1.25 mM for 2-wk in hydroponic system. PV was effective in accumulating large amounts of As (4598 and 1160 mg/kg in the fronds and roots at 0.05 mM AsV) and Cr (234 and 12,630 mg/kg in the fronds and roots at 0.05 mM CrVI). However, when co-present, AsV and CrVI acted as inhibitors, negatively impacting their accumulation in PV. Arsenic accumulation in the fronds was reduced by 92% and Cr by 26%, indicating reduced As and Cr translocation. However, addition of sulfate increased uptake and translocation of As by 26–28% and Cr by 1.63 fold. This experiment demonstrated that As and Cr inhibited each other in uptake and translocation by PV but sulfate enhanced As and Cr uptake and translocation by PV.

The application of agrochemicals in Southeast Asia is increasing in rate, variety and toxicity with alarming speed. Understanding the behavior of these different contaminants within the environment require comprehensive monitoring programs as well as accurate simulations with hydrological models. We used the SWAT hydrological model to simulate the fate of three different pesticides, one of each usage type (herbicide, fungicide and insecticide) in a mountainous catchment in Northern Thailand. Three key parameters were identified: the sorption coefficient, the decay coefficient and the coefficient controlling pesticide percolation. We yielded satisfactory results simulating pesticide load dynamics during the calibration period (NSE: 0.92–0.67); the results during the validation period were also acceptable (NSE: 0.61–0.28). The results of this study are an important step in understanding the modeling behavior of these pesticides in SWAT and will help to identify thresholds of worst-case scenarios in order to assess the risk for the environment.