In a risk assessment study the environmental fate of the herbicide glyphosate was studied with the specific background of the presence of genetically modified (GM) plants. Aim was to simulate the environmental behaviour of glyphosate in sandy field soil lysimeters after multiple herbicide applications and under the presence of GM soybean and to test and enhance model reliability in the simulation of the herbicide fate including biodegradation in the soil and herbicide translocation in GM plants. The modelling of the herbicide behaviour in the present study was based on the pesticide transport model LEACHP and the model PLANTX to simulate the pesticide uptake by plants. Both models were implemented in the modular modelling system EXPERT-N. Glyphosate transport measurements and the mathematical modelling results indicate that due to the high sorption of glyphosate to the soil matrix and the high microbial capacities for glyphosate degradation in the lysimeter soil, leaching risk can be considered to be low. We confirmed that the introduction of more adequate conceptual descriptions of microbial response to pesticide and nutrient additions can contribute to a reduction in the uncertainty of pesticide degradation modelling. Moreover, the consideration of uncertainty in sorption, dispersivity and degradation parameters revealed a considerable variability in model output. The observed accumulation of glyphosate in roots and nodules was reproduced by the simulation results. Under the restriction that the prevailing model assumptions are valid, the simulation results indicate that glyphosate may accumulate also in beans of trangenic soybean.

Human exposure to volatile organic compounds (VOCs) and residential indoor and outdoor VOC levels had hitherto not been investigated in Turkey. This study details investigations of indoor, outdoor, and personal exposure to VOCs conducted simultaneously in 15 homes, 10 offices and 3 schools in Kocaeli during the summer of 2006 and the winter of 2006–2007. All VOC concentrations were collected by passive sampling over a 24-h period and analyzed using thermal desorption (TD) and a gas chromatography/flame ionization detector (GC/FID). Fifteen target VOCs were investigated and included benzene, toluene, m/p-xylene, o-xylene, ethylbenzene, styrene, cyclohexane, 1,2,4-trimethylbenzene, n-heptane, n-hexane, n-decane, n-nonane, n-octane and n-undecane. Toluene levels were the highest in terms of indoor, outdoor, and personal exposure, followed by m/p-xylene, o-xylene, ethylbenzene, styrene, benzene and n-hexane. In general, personal exposure concentrations appeared to be slightly higher than indoor air concentrations. Both personal exposure and indoor concentrations were generally markedly higher than those observed outdoors. Indoor target compound concentrations were generally more strongly correlated with outdoor concentrations in the summer than in winter. Indoor/outdoor ratios of target compounds were generally greater than unity, and ranged from 0.42 to 3.03 and 0.93 to 6.12 in the summer and winter, respectively. Factor analysis, correlation analyses, indoor/outdoor ratios, microenvironment characteristics, responses to questionnaires and time activity information suggested that industry, and smoking represent the main emission sources of the VOCs investigated. Compared with the findings of earlier studies, the level of target analytes in indoor air were higher for several target VOCs, indicating a possible trend toward increased inhalation exposure to these chemicals in residential environments.

Nitrated Polycyclic Aromatic Hydrocarbons (NPAH) were determined in the suspended particulates collected in São Paulo (Brazil) and three other cities lying in the São Paulo State, (namely, Araraquara, Piracicaba and Paulínia), during August 2002 and July 2003. São Paulo samples represented a big difference between two groups of days, one of which characterized by heavy injection of pollutants released by industrial and agricultural activities. Most NPAH congeners identified in the atmosphere were among those usually associated to diesel exhaust, with the three important exceptions of 2-nitrofluoranthene, 2- and 4-nitropyrene. Daytime reactions seemed to promote decomposition of primary fluoranthene and pyrene. Trends of NPAH at all sites seemed to be associated to regional transport of polluted air through air masses passing over sugar cane plantations of São Paulo State.

Prescribed or natural drawdowns occur frequently in reservoirs but their effects on fish populations have been barely studied. As a consequence of a severe drought and the need to optimize water quality, a partial drawdown was prescribed in autumn 2005 to a eutrophic reservoir that provides water supply to a large metropolitan area (Barcelona, Spain). In order to avoid a potential massive fish kill given the reduced oxygen availability and high fish abundance, preventive purse seine fisheries were performed to reduce the fish stock. The fisheries had little effect on the fish assemblage because final population size structure and species composition did not change significantly. The species composition of the purse seine catches varied significantly during the drawdown with higher proportion of bleak (Alburnus alburnus) in pelagic water during the days of worst water quality, confirming that bleak is more tolerant than roach (Rutilus rutilus) to poor water quality and a potential good indicator of water pollution. The weight-length relationship (i.e. condition) of roach and bleak also varied significantly during the drawdown following the same tendency in both species, losing and recovering their weight (4.99% in roach and 5.96% in bleak) in only 16 days. The close relationship found between water quality and fish condition demonstrates that fish condition can be a good metric of the well being of fish, even for extreme short-term changes.

The Paraíba do Sul river is located in one of the most developed part of Brazil and receives many organic and industrial effluents directly affecting the ichthyofauna. Concentration of four heavy metals (Cu, Cr, Zn and Pb) were determined in two tissues (muscle and gonads) of three abundant fish species from different trophic levels (Oligosarcus hepsetus--carnivore, Geophagus brasiliensis--omnivore and Hypostomus luetkeni--detritivore) between November 2002 and April 2003. The aim was to test the hypothesis that the trophic level and the proximity from impacted areas influence levels of contamination and to assess if these species are indicators of large-scale habitat quality. Levels of heavy metals were detected by Total Reflection X-ray Fluorescence with Synchrotron Radiation (SR-TXRF) at the Brazilian National Synchrotron Radiation Laboratory (LNLS). Generally, gonads showed higher metal concentration than muscles, except for Cr. All examined metals, but Cu, exceeded the maximum permitted concentration (mpc) by the Brazilian legislation for human consumption in at least one tissue. O. hepsetus (carnivore) showed the highest contamination levels, followed by G. brasiliensis (omnivore) and H. luetkeni (detritivore). The middle-upper segment, which encompasses large urban areas, showed the highest levels of metal contamination in most cases. O. hepsetus showed the highest levels of contamination in muscles for Pb in the middle-upper river segment (7.98 ± 3.73; mpc = 2.0 μg g-¹) and for Cr in the upper (5.53 ± 0.05; mpc = 0.10 μg g-¹) and middle-upper (4.20 ± 0.85; mpc = 0.10 μg g-¹) segments, which indicates that human population should avoid to consume these fishes species from these segments of the Paraíba do Sul river.

A lysimeter study was performed to monitor effects of elevated ozone on juvenile trees of Fagus sylvatica L. as well as on the plant-soil system. During a fumigation period over almost three growing seasons, parameters related to plant growth, phenological development and physiology as well as soil functions were studied. The data analyses identified elevated ozone to delay leaf phenology at early and to accelerate it at late developmental stages, to reduce growth, some leaf nutrients (Ca, K) as well as some soluble phenolics (hydroxycinnamic acid derivatives, total flavonol glycosides). No or very weak ozone effects were found in mobile carbon pools of leaves (starch, sucrose), and other phenolic compounds (flavans). Altered gene expression related to stress and carbon cycling corresponded well with findings from leaf phenology and chemical composition analyses indicating earlier senescence and oxidative stress in leaves under elevated ozone. Conversely in the soil system, no effects of ozone were detected on soil enzyme activities, rates of litter degradation and lysimeter water balances. Despite the fact that the three reported years 2003-2005 were climatically very contrasting including a hot and dry as well as an extremely wet summer, and also mild as well as cold winters, the influence of ozone on a number of plant parameters is remarkably consistent, further underlining the phytotoxic potential of elevated tropospheric ozone levels.

Xenobiotic compounds are widely used in several industries; hence they frequently appear in industrial wastewaters. It is a well-known fact that even the discharge of conventionally treated wastewater may have adverse effects on the receiving water environment. Turkey, a developing EU applicant country, has many industrial sectors producing large amounts of xenobiotic-containing wastewaters. The problem is only enlarged by the lack of monitoring of these substances due to the deficiencies associated with their analysis and detection. Thus, studies in Turkey are based on the use of some collective parameters as a substitute for the xenobiotic itself. Biological, physicochemical, and integrated treatment technologies have been investigated for the removal and/or minimization of the possible adverse effects of xenobiotics in industrial wastewaters. In this respect, this paper provides an overview of the studies conducted on xenobiotic-containing wastewaters from specific industries in Turkey. Although the studies add invaluable information to the scientific background on the subject, new research on the exact biochemical mechanisms of xenobiotic biodegradation will further extend our understanding for improving treatment.

To assess possible adverse effects of residual chlorines from hypochlorite-treated seawater to non-target marine organisms, bioassays were carried out on marine amphipod Hyale barbicornis and estuarine fish Oryzias javanicus. Acute toxicity tests were first conducted using various concentrations of sodium hypochlorite (NaOCl) followed by a long-term exposure to residual chlorines from a test water treated with 1 mg L⁻¹ NaOCl. Results showed that NaOCl was acutely toxic to both organisms. However, long-term exposure to residual chlorines from NaOCl-treated waters caused no major adverse effects to both organisms under laboratory conditions since free chlorines in the treated water was reduced to about 10% by 23-h holding and 1-h aeration. No H. barbicornis died but residual chlorine-exposed juveniles had significantly shorter body lengths at the end of exposure. Residual chlorine-exposed O. javanicus also showed no significant differences to that of the control in all measured endpoints except for hatching time. The results suggest that using 1 mg L⁻¹ NaOCl for disinfection of ballast waters will produce residual chlorines that is far below the LC50 and EC50 of H. barbicornis and O. javanicus even on a long-term basis.

Predicting the environmental effects of de-icing salt requires knowledge of the pathways taken by salt from on-road application through spread to the surroundings to deposition and fate in the roadside environment. This study described differences in chloride deposition and distribution in soil with increasing distance from the road by means of field observations and modelling. The dynamic modelling approach successfully represented the spread of de-icing salt from road to surroundings, deposition in the roadside environment and the subsequent infiltration into roadside soil. The general decrease in soil chloride content with distance from the road was described by differences in salt deposition, soil physical properties, vegetation properties and snow characteristics. The uncertainty in model predictions was highest in areas close to the road due to a complex combination of high salt deposition, snow-ploughed masses and road runoff. The exponential decline in salt deposition with distance from the road could not be justified close to the road. Different types of field investigations were applied in a calibration procedure to establish reasonable ranges for the most influential model parameters. Measured electrical resistivity reflected well the changes in simulated chloride content in soil during winter and spring when chloride concentrations were high. However, during summer or periods with low chloride concentrations the measured resistivity was substantially lower than simulated values, as it reflected the total contamination level in soil.

A coagulation treatment study was conducted using both natural (sago and potato flour) and commercial (poly aluminum chloride and aluminum sulfate) coagulants in semiconductor wastewater. The effects for settling time and dosage of the coagulants as well as their interactions on the reduction of chemical oxygen demand (COD) and turbidity were investigated using a three level factorial design, Response Surface Methodology (RSM). Sago concentration showed more influence on the COD and turbidity reduction than settling time, with concentrations lower than 1.5 g L⁻¹ giving the better reduction. The interaction of settling time and concentration on the COD and turbidity were observed when using potato starch. Concentrations higher than 1.5 g L⁻¹ potato starch reduced the COD and turbidity better. The polyaluminium chloride and ammonium sulphate revealed that lower concentrations (0.02-1.0 g L⁻¹) and longer settling time (30-60 min) gave the greatest reduction in COD and turbidity.