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Krebstein K.,Estonian University of Life Sciences | von Janowsky K.,Institute for Hygiene and Environment | Kuht J.,Estonian University of Life Sciences | Reintam E.,Estonian University of Life Sciences
Plant, Soil and Environment | Year: 2014

The objective of this work was to evaluate the effect of tractor wheeling with a light tractor on the root growth and soil properties of smooth brome in South Estonia. Field experiment was conducted on sandy loam Haplic Luvisol in 2007. Data were collected during September 2008 in both an uncompacted and compacted area. Because of the compaction, the precompression stress increased in the upper soil layer (0-10 cm) by 12.6% and 15.2% at a depth of 10-20 cm. Compaction had only a minor effect on the bulk density, values increased 4.7% in the upper soil layer and 1.8% in the deeper layer. Differences in the saturated hydraulic conductivity (ks) were not significant; however, the decrease in the ks was 26.6% in the upper level and 12.5% in the deeper (10-20 cm) layer. At a depth of 0 to 30 cm compaction decreased the root length by 44.7% and the root mass by 60.5% compared with the uncompacted soil. Altogether, this study confirms the unfavourable effect of wheeling on grasslands even when the wheeling is performed with a light tractor on dry soil.

Grohmann L.,Federal Office of Consumer Protection and Food Safety | Busch U.,Bavarian Health and Food Safety Authority | Pecoraro S.,Bavarian Health and Food Safety Authority | Hess N.,Institute for Hygiene and Environment | And 2 more authors.
European Food Research and Technology | Year: 2011

A real-time PCR-based method for construct-specific detection of the genetically modified (GM) linseed event 'CDC Triffid' FP967 originating from Canada has been validated in a collaborative trial. The construct-specific method amplifies a 105 bp long fragment of the transgenic insertion present in FP967 spanning the junction of the terminator region of the nopalin synthase gene from Agrobacterium tumefaciens (Tnos) to a sequence region coding for the dehydrofolate reductase gene (dfr) from a class I integron from Escherichia coli. This region is characteristic for the construct used to develop FP967. A total of 11 laboratories participated in the collaborative study. For PCR analysis, each laboratory received 14 DNA samples comprising 7 double-blind DNA samples. The samples consisted of two low GM-levels of FP967 DNA (10 or 50 copies per PCR), of DNA from two different GM-positive linseed products and of DNA from GM-negative linseed, potato and rapeseed materials, respectively. All but one of the FP967-positive DNA samples were detected correctly. No false-positive results were reported. The results demonstrate that the linseed event FP967 is detectable even at low copy number concentrations. The limit of detection (LOD) determined with plasmid DNA was shown to be at 5 copies of the Tnos-dfr sequence. The data provided show that the method can be applied successfully in different laboratories and is fit-for-purpose to test for the presence of the EU-unauthorised linseed event 'CDC Triffid' FP967. © 2011 Springer-Verlag.

Li Z.,University of Stockholm | Sobek A.,University of Stockholm | Radke M.,University of Stockholm | Radke M.,Institute for Hygiene and Environment
Environmental Science and Technology | Year: 2016

A considerable knowledge gap exists with respect to the fate and environmental relevance of transformation products (TPs) of polar organic micropollutants in surface water. To narrow this gap we investigated the fate of 20 parent compounds (PCs) and 11 characteristic TPs in four wastewater-impacted rivers. Samples were obtained from time-integrated active sampling as well as passive sampling using polar organic chemical integrative samplers (POCIS). Seventeen out of the 20 PCs were detected in at least one of the rivers. All the PCs except acesulfame, carbamazepine, and fluconazole were attenuated along the studied river stretches, with the largest decrease found in the smallest river which had an intense surface water-pore water exchange. Seven TPs were detected, all of which were already present directly downstream of the WWTP outfall, suggesting that the WWTPs were a major source of TPs to the recipients. For anionic compounds, attenuation was the highest in the two rivers with the lowest discharge, while the pattern was not as clear for neutral or cationic compounds. For most compounds the results obtained from active sampling were not significantly different from those using POCIS, demonstrating that the cost and labor efficient POCIS is suitable to determine the attenuation of organic micropollutants in rivers. © 2016 American Chemical Society.

Su T.,Tongji University | Su T.,University of Stockholm | Deng H.,Tongji University | Benskin J.P.,University of Stockholm | And 2 more authors.
Chemosphere | Year: 2016

Occurrence of the antibiotic sulfamethoxazole (SMX) in the aquatic environment is of concern due to its potential to induce antibiotic resistance in pathogenic bacteria. While degradation of SMX can occur by numerous processes, the environmental fate of its transformation products (TPs) remains poorly understood. In the present work, biodegradation of SMX photo-TPs was investigated in a water/sediment system. Photo-TPs were produced by exposing SMX to artificial sunlight for 48 h. The resulting mixture of 8 photo-TPs was characterized using a combination of ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry and tandem mass spectrometry, and then used in biodegradation experiments. Significant differences in transformation among SMX photo-TPs were observed in the water/sediment system, with four photo-TPs displaying evidence of biodegradation (dissipation half-lives [DT50] of 39.7 d for 3-amino-5-methylisoxazole, 12.7 d for 4-nitro-sulfamethxoazole, 7.6 d for an SMX isomer and 2.4 d for [C10H13N3O4S]), two displaying primarily abiotic degradation (DT50 of 31 d for sulfanilic acid and 74.9 d for 5-methylisoxazol-3-yl-sulfamate), and two photo-TPs behaving largely recalcitrantly. Remarkably, TPs previously reported to be photo-stable also were persistent in biodegradation experiments. The most surprising observation was an increase in SMX concentrations when the irradiated solution was incubated, which we attribute to back-transformation of certain photo-TPs by sediment bacteria (85% from 4-nitro-sulfamethoxazole). This process could contribute to exposure to SMX in the aquatic environment that is higher than one would expect based on the fate of SMX alone. The results highlight the importance of considering TPs along with their parent compounds when characterizing environmental risks of emerging contaminants. © 2016 Elsevier Ltd.

Plenge-Bonig A.,Institute for Hygiene and Environment | Soto-Ramirez N.,University of South Carolina | Karmaus W.,University of South Carolina | Petersen G.,Wyeth Pharma Germany | And 2 more authors.
European Journal of Pediatrics | Year: 2010

To assess whether breastfeeding protects against acute gastroenteritis (AGE) due to rotavirus (RV) infection compared to RV-negative AGE (RV-) in children age 0-12 months. Data from a community-based study of children with AGE from 30 pediatric practices in Germany, Switzerland, and Austria were evaluated. A case-control design was conducted with RV-positive AGE (RV+) cases and RV- AGE as controls. Odds ratios and 95% confidence intervals were estimated using log-linear regression models adjusting for child's age, family size, number of siblings, child care attendance, and nationality. A total of 1,256 stool samples were collected from infants with AGE; 315 (25%) were RV+ and 941 RV-. Being breastfed in the period of disease inception reduced the risk of AGE due to RV+ (OR, 0.53; 95% CI, 0.37-0.76). In infants 0-6 months of age, the protective effect was stronger (OR, 0.33; 95% CI, 0.19-0.55) than in 7-12-month-old children. Our study adds to the evidence of a protective concurrent effect of breastfeeding against rotavirus infection in infants, particularly in children 6 months and younger. Breastfeeding is important to diminish rotavirus-related gastroenteritis in infants before vaccination can be introduced. © 2010 Springer-Verlag.

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