Six trace contaminants (acesulfame (ACE), sucralose (SUC), carbamazepine (CBZ), diatrizoic acid (DTA), 1H-benzotriazole (BTZ) and its 4-methyl analogue (4-TTri)) were traced from wastewater treatment plants (WWTPs) to receiving waters and further to riverbank filtration (RBF) wells to evaluate their prediction power as potential wastewater markers. Furthermore, the persistence of some compounds was investigated in advanced wastewater treatment by soil aquifer treatment (SAT). During wastewater treatment in four conventional activated sludge WWTPs ACE, SUC, and CBZ showed a pronounced stability expressed by stable concentration ratios in influent (in) and effluent (out) (ACE/CBZ: in45, out40; SUC/CBZ: in1.8, out1.7; and ACE/SUC: in24, out24). In a fifth WWTP, additional treatment with powdered activated carbon led to a strong elimination of CBZ, BTZ, and 4-TTri of about 80% and consequently to a distinctive shift of their ratios with unaffected compounds. Data from a seven month monitoring program at seven sampling locations at the rivers Rhine and Main in Germany revealed the best concentration correlation for ACE and CBZ (r(2) = 0.94) and also a good correlation of ACE and CBZ concentrations to BTZ and 4-TTri levels (r(2) = 0.66 to 0.82). The comparison of ratios at different sampling sites allowed for the identification of a CBZ point source. Furthermore, in Switzerland a higher consumption of SUC compared to Germany can be assumed, as a steadily increasing ACE/SUC ratio along the river Rhine was observed. In RBF wells a good correlation (r(2) = 0.85) was again observed for ACE and CBZ. Both also showed the highest stability at a prolonged residence time in the subsurface of a SAT field. In the most peripheral wells ACE and CBZ were still detected with mean values higher than 36 µg L(-1) and 1.3 µg L(-1), respectively. Although SUC concentrations in wastewater used for SAT decreased by more than 80% from about 18 µg L(-1) to 2.1 µg L(-1) and 3.5 µg L(-1) in these outlying wells, the compound was still adequate to indicate a wastewater impact in a qualitative way.

In this paper, results of an extensive monitoring programme for pharmaceutical residues in the river Rhine are presented. For one decade (1997 until 2006), the occurrence of widely used human pharmaceuticals like analgesics, lipid regulators, antiepileptics and others has been studied at four locations along the river Rhine. The results of more than 500 analyses clearly prove that compounds such as carbamazepine or diclofenac are regularly found in the river Rhine in concentrations up to several hundred ng per litre. Combining concentration levels with data on water flow enables the calculation of transports, which e.g. for carbamazepine or diclofenac were in the range of several tons per year. The evaluation of the long-term monitoring data shows that only a slight decrease in concentration levels as well as in annual transports can be observed and thus the contamination of the river Rhine by pharmaceutical residues during the last decade has to be regarded as almost constant. Seasonal variations can be detected for bezafibrate, diclofenac and ibuprofen, for which the concentrations are much lower in the summer months. A more effective removal during wastewater treatment in the warmer periods of the year seems to be the major reason for those variations. For carbamazepine, no comparable seasonal effect can be found.

The fate of persistent organic pollutants in sea ice is a poorly researched area and yet ice serves as an important habitat for organisms at the base of the marine foodweb. This study presents laboratory-controlled experiments to investigate the mechanisms governing the fate of organic contaminants in sea ice grown from artificial seawater. Sea ice formation was shown to result in the entrainment of chemicals from seawater, and concentration profiles in bulk ice generally showed the highest levels in both the upper (ice− atmosphere interface) and lower (ice−ocean interface) ice layers, suggesting their incorporation and distribution is influenced by brine advection. Results from a 1-D sea ice brine dynamics model supported this, but also indicated that other processes may be needed to accurately model low-polarity compounds in sea ice. This was reinforced by results from a melt experiment, which not only showed chemicals were more enriched in saltier brine, but also revealed that chemicals are released from sea ice at variable rates. We use our results to demonstrate the importance of processes related to the occurrence and movement of brine for controlling chemical fate in sea ice which provides a pathway for exposure to ice-associated biota at the base of the pelagic food web.

et al. recently described a protective effect of the apolipoprotein E4 allele concerning the severity of liver damage in chronic hepatitis C virus (HCV) infection. 1 Their findings were explained by apolipoprotein E4 allele-specific changes in lipoprotein metabolism, 2 which seems to be integrally linked to the process of HCV uptake into hepatocytes. [3][4][5] Following their interesting data we examined whether carriage of an apolipoprotein E4 allele also affects the treatment outcome in chronic HCV infection. We therefore correlated the individual apolipoprotein E allele status with the treatment response of 506 consecutive chronically HCV-infected patients in a retrospective analysis. All of them had been treated with combination therapy at the Outpatient Departments of the Universities of Berlin and Homburg (Germany) with either interferon and ribavirin (n ϭ 303) or pegylated interferon and ribavirin (n ϭ 203). Apolipoprotein E genotyping was performed by restriction fragment length polymorphism. In total, 286 (56.5%) patients showed a sustained virologic response (SVR), defined as qualitative HCV-RNA negative at the end of a 24-week follow-up period.A tendency for decreasing SVR rates could be observed depending on the individual apolipoprotein E4 allele status (58% SVR in E3/3 vs. 51% SVR in E3/4 vs. 43% SVR in E4/4; Table 1). Stratification for HCV genotype 1-infected patients revealed that patients with at least one apolipoprotein E4 allele showed significantly lower SVR compared with patients without an apolipoprotein E4 allele (Table 1). By analyzing the underlying allele frequencies an association of the apolipoprotein E4 allele with reduced SVR rates became evident (30% SVR for the E4 allele vs. 42% SVR for non-E4, odds ratio, 0.58; 95% CI, 0.345-0.967; P ϭ .037; data not shown).Taken together, our findings suggest that the presence of an apolipoprotein E4 allele goes along with lower SVR rates in chronic HCV infection. However, this association is only significant in patients with HCV genotype 1 infection. The reasons for this kind of relationship still remain obscure. HCV genotype-specific factors affecting the HCV-apolipoprotein E interaction have been previously discussed. 6 The apolipoprotein E4 allele is known to be associated with increased LDL and the E2 allele with reduced LDL plasma concentrations. 7 On the other hand, higher LDL levels seem to affect-as observed in other diseases-cytokine release 8 and antiviral cellular immune response. 9,10 Thus, this kind of mechanism, i.e., apolipoprotein E4 -associated hy-

Long-term air monitoring datasets are needed for persistent organic pollutants (POPs) to assess the effectiveness of source abatement measures and the factors controlling ambient levels. The Toxic Organic Micro Pollutants (TOMPs) Network, which has operated since 1991, collects ambient air samples at six sites across England and Scotland, using high-volume active air samplers. The network provides long-term ambient air trend data for a range of POPs at both urban and rural locations. Data from the network provides the UK Government, regulators and researchers with valuable information on emission/source controls and on the effectiveness of international chemicals regulation such as the Stockholm Convention and UN/ECE Protocol on POPs. The target chemicals of TOMPs have been polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and, since 2010, polybrominated diphenyl ethers (PBDEs). The continuous monitoring of these compounds demonstrates the constant decline in UK air concentrations over the last two decades, with average clearance rates for PCDD/Fs in urban locations of 5.1 years and for PCBs across all sites 6.6 years. No significant declines in rural locations for PCDD/Fs have been observed. There is a strong observable link between the declining ambient air concentrations and the emission reductions estimated in the annually produced National Atmospheric Emission Inventory (NAEI) dataset. These findings clearly demonstrate the unique strengths of long-term consistent datasets for the evaluation of the success of chemical regulation and control.

Combinatorial biosynthesis has great potential for designing synthetic circuits and amplifying the production of new active compounds. Studies on multienzyme cascades are extremely useful for improving our knowledge on enzymatic catalysis. In particular, the elucidation of enzyme substrate promiscuity can be potentially used for bioretrosynthetic approaches, leading to the design of alternative and more convenient routes to produce relevant molecules. In this perspective, plant-derived polyketides are extremely adaptable to those synthetic biological applications. Here, we present a combination of an in vitro CoA ligase activity assay coupled with a bacterial multigene expression system that leads to precursor-directed biosynthesis of 21 flavonoid derivatives. When the vast knowledge from protein databases is exploited, the herein presented procedure can be easily repeated with additional plant-derived polyketides. Lastly, we report an efficient in vivo expression system that can be further exploited to heterologously express pathways not necessarily related to plant polyketide synthases.

Highlights 12 types of PUF passive air samplers were deployed in an intercomparison exercise. Differences in sampler design lead to small variations in sampler performance. Replicate PUF air samples were sent to 14 laboratories to assess variability in data. Laboratories report very different concentrations of POPs, PAHs in identical samples. Analytical uncertainties must be addressed for comparability of air monitoring data.

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