Chiral pesticides comprise a new and important class of environmental pollutants nowadays. With the development of industry, more and more chiral pesticides will be introduced into the market. But their enantioselective ecotoxicology is not clear. Currently used synthetic pyrethroids, organophosphates, acylanilides, phenoxypropanoic acids and imidazolinones often behave enantioselectively in agriculture use and they always pose unpredictable enantioselective ecological risks on non-target organisms or human. It is necessary to explore the enantioselective toxicology and ecological fate of these chiral pesticides in environmental risk assessment. The enantioselective toxicology and the fate of these currently widely used pesticides have been discussed in this review article.

The main objective of this study was to compare the effectiveness of different methods (heavy metals in pore water (PW), diffusive gradients in thin films (DGT), diethylene triamine pentaacetic acid (DTPA) extraction, and total heavy metals (THM) in soil) for the assessment of heavy metal bioavailability from soils having various properties and heavy metal contents. The effect of soil heavy metal pollution on shoot yield and sulfatase enzyme activity was also studied. Wheat (Triticum aestivum) was grown in different soils from Spain (n = 10) and New Zealand (n = 20) in a constant environment room for 25 days. The bioavailabilities of Cd, Cr, Cu, Ni, Pb, and Zn were assessed by comparing the metal contents extracted by the different methods with those found in the roots. The most widely applicable method was DGT, as satisfactory Cu, Ni, Pb, and Zn root concentrations were obtained, and it was able to distinguish between low and high Cr values. The analysis of the metal concentrations in PW was effective for the determination of Cr, Ni, and Zn content in root. Copper and Pb root concentrations were satisfactorily assessed by DTPA extraction, but the method was less successful with determining the Ni and Cr contents and suitable just to distinguish between high and low concentrations of Zn. The THM in soil method satisfactorily predicted Cu and Pb root concentrations but could only be used to distinguish between low and high Cr and Zn values. The Cd root concentration was not successfully predicted for any of the used methods. Neither shoot yield nor sulfatase enzyme activity was affected by the metal concentrations.

Amine-functionalized SiO₂/TiO₂ photocatalytic films have been synthesized using the peroxo titanic acid (PTA) approach coupled with the sol-gel dip-coating method. The 3-aminopropyl-trimethoxysilane (APTMS) and methyltrimethoxysilane (MTMOS) were employed as the amine functional groups and silica precursor. The effects of the ratio of APTMS/MTMOS, PTA refluxed time, and pH of prepared sol on the characteristics and the formaldehyde degradation efficiency were investigated. Physicochemical properties of prepared photocatalysts were characterized with nitrogen adsorption-desorption isotherm measurement, SEM, X-ray diffraction (XRD), UV-vis spectrophotometer, and Fourier transform infrared (FTIR) spectroscopy. The XRD and FTIR results indicated that the obtained photocatalysts consisted of -NH₂ groups, SiO₂, and anatase TiO₂. The photocatalytic films showed high transmittance of 80-90% in the visible light region. The obtained film prepared with the APTMS/MTMOS ratio of 0.03, pH of 1.8, and 10 h of refluxed time possessed high specific surface area (604.0 m² g⁻¹) and 85% formaldehyde degradation efficiency. The enhancement of formaldehyde degradation efficiency was observed when increasing the PTA refluxed time. The repeatability of photocatalytic film was also tested, and the degradation efficiency was 92.0% of initial efficiency after seven cycles.

Background Chlorobenzoic acids (CBA) are intermediate products of the aerobic microbial degradation of PCB and several pesticides. This study explores the feasibility of using basket willows, Salix viminalis, to remove 4-CBA from polluted sites, which also might stimulate PCB degradation. Methods The removal of 4-CBA by willow trees was investigated with intact, septic willow trees growing in hydroponic solution and with sterile cell suspensions at concentrations of 5 mg/L and 50 mg/L 4-CBA. Nutrient solutions with different levels of ammonium and nitrate were prepared to achieve different pH levels. The concentration of 4-CBA was tracked over time and quantified by HPLC. Results and discussion At the low level of 4-CBA (5 mg/L), willows removed 70% (pH 4.2) to 90% (pH 6.8), while 48% (pH 4.2) to 52% (pH 6.8) of the water was transpired. At the high 4-CBA level (50 mg/L), the pH varied between 4.4 and 4.6, and 10% to 30% of 4-CBA was removed, but only 5% to 9% of the water. In sterile cell suspensions, removal of 4-CBA by fresh biomass was much higher than removal by dead biomass. Conclusions The results indicate that 4-CBA is toxic to willow trees at 50 mg/L. The removal of 4-CBA from solution is by both passive processes (uptake with water, sorption to plant tissue) and metabolic processes of the plants. Recommendations and outlook Plants, such as willow trees, might assist in the degradation of PCB and their degradation products CBA.

Background, aim and scope Perfluorinated compounds (PFCs) are global environmental pollutants that bioaccumulate in wildlife and humans. Laboratory experiments have revealed toxic effects such as delayed development, humoral suppression, and hepatotoxicity. Although numerous human blood levels have been reported, little is known about distribution in the human body. Knowledge about PFC distribution and accumulation in the human body is crucial to understanding uptake and subsequent effects as well as to conduct risk assessments. The present study reports PFC levels in human liver and breast milk from a general population living in Catalonia, Spain. Liver and milk levels are compared to previously reported levels in blood from the same geographic area as well as to other existing reports on human liver and milk levels in other countries. Materials and methods Human liver (n = 12) and milk (n = 10) samples were collected in 2007 and 2008 in Catalonia, Spain. Liver samples were taken postmortem from six males and six females aged 27-79 years. Milk samples were from healthy primipara women (30-39 years old). Both liver and milk were analyzed by solid-phase extraction and ultra-performance liquid chromatography tandem mass spectrometry. Results Six PFCs were detected in liver, with perfluorooctanesulfonate (PFOS, 26.6 ng/g wet weight) being the chemical with the highest mean concentration. Other PFCs such as perfluorohexanesulfonate (PFHxS), perfluorooctanoic acid (PFOA), and acids with chain lengths up to C11 were also detected, with mean levels ranging between 0.50 and 1.45 ng/g wet weight. On the other hand, PFOS and PFHxS were the only PFCs detected in human milk, with mean concentrations of 0.12 and 0.04 ng/mL, respectively. Discussion While milk concentrations were similar to reported levels from other countries, liver samples contained more PFCs above quantification limits and higher PFOS concentrations compared to the only two other reports found in the literature. Differences between the results of the present study and those concerning previous investigations can be due to declining levels of some PFCs, which have been reported for the USA. The relationship between PFC concentrations in human liver, milk, and blood was assessed using blood concentrations previously determined in Catalonia. Those levels resulted in liver/serum ratios of 1.7:1, 1.4:1, and 2.1:1 for PFOS, perfluorodecanoic acid, and perfluoroundecanoic acid, respectively. Accumulation in liver is suggested for PFOS and the perfluorocarboxylic acids with carbon chain lengths C9, C10, and C11. For PFOA and PFHxS, fivefold and 14-fold higher concentrations, respectively, were seen in serum as compared to liver. The mean concentration of PFOS and PFHxS in milk was only 0.8% and 0.6% of the reported mean serum level, respectively. Conclusions The results of the present study show that several PFCs could be detected in human liver samples of subjects living in Tarragona. Concerning human milk, the mechanism by which PFCs are transferred from mother's blood to breast milk is still unclear. Considering that PFCs are strongly bound to the protein fraction in blood, the possibility of PFCs entering the milk and accumulating to levels observed in maternal plasma is limited. Recommendations and perspectives Interestingly, the potential accumulation difference for PFCs with different chain lengths might be of great importance for risk assessment. Continuing studies on the distribution of different PFCs in human tissue are therefore justified.

Purpose In this study, seasonal variations in the concentration profile of four analgesics and one lipid regulator were monitored on their way from a wastewater treatment plant (WWTP) effluent, along a river, and into a lake. Methods From December 2007 to December 2008, water samples were collected monthly (n = 12) from an upstream point, the effluent, four downstream points of the WWTP, and at the point where the river merges with the lake, and the concentrations of ibuprofen, naproxen, bezafibrate, diclofenac, and ketoprofen were determined. The analytical methodology involved solid-phase extraction of the target compounds from water samples followed by liquid chromatography coupled with tandem mass spectrometry for compound separation and detection. Results The studied pharmaceuticals were found in the effluent at concentrations ranging from 31 to 1,852 ng l⁻¹ depending on the season. In the river and lake, the concentrations were much lower (6-400 ng l⁻¹) mainly due to dilution but also to a season-dependent contribution from natural transformation processes. The mean mass flow of all analgesics was highest during winter while the highest mean mass flow of the lipid regulator bezafibrate was observed in spring. Conclusions The WWTP is the main source of the target compounds in the aquatic environment. The observed winter accumulation signifies the importance of natural transformation processes, which can only be estimated based on mass flow data, on the fate of pharmaceuticals in the environment.