Multivariate analysis of the bioaccumulation of polychlorinated biphenyls (PCBs) in the marine pelagic food web from the southern part of the Baltic Sea,Poland

The concentration, pattern, bioaccumulation and biomagnification features of many chlorobiphenyl congeners including non- and mono-ortho chlorine substituted members have been determined in a pelagic food chain including mixed phyto- and zooplankton, herring (Clupea harengus), harbour porpoise (Phocoena phocoena) and black cormorants (Phalacrocorax carbo sinensis) collected from the southern part of the Baltic Proper. TCDD (tetrachlorodibenzo-p-dioxin) toxic equivalents (TEQs) in plankton, herring, harbour porpoise and cormorants were 0.42, 5.3, 79 and 2,700 pg g(-1) lipid weight, respectively. Concentrations of total polychlorinated biphenyls (PCBs) in plankton, herring, harbour porpoise and cormorants were 1.9, 120, 8700 and 2,100 ng g(-1) wet weight (210, 1,300, 10,000 and 42,000 ng g(-1) lipid weight) respectively. Herring, harbour porpoise and black cormorant apparently bioaccumulate many PCBs found in their food, and the values of the bioaccumulation factors (BAFs) for PCBs were approximately 10 in herring, 35 in harbour porpoise and up to 300 in breast muscle of cormorants. Harbour porpoise clearly is able to metabolize the most toxic non-ortho PCBs (no. 77, 126 and 169) and a few mono-ortho PCBs (no. 114, 123 and 156), while all non- and mono-ortho PCBs are bioaccumulated by herring. Penta-, hexa- and hepta-CBs were the dominatant homologue classes both in the muscle tissue and liver. PCB congeners nos. 201, 209, 172/192, 194 and 195 were characterized by the largest BAFs (between 100 and 300). Principal component analysis has been used to analyse the interdependences and differences in the CB congener accumulation patterns between the components of the investigated pelagic food web.     

A direct observation study of nighttime safety belt use in Indiana

INTRODUCTION: Nearly all direct observation studies of safety belt use are conducted exclusively during daylight hours. Recent work has suggested that safety belt use at night may differ from daytime belt use. METHODS: An observational study of nighttime safety belt use, utilizing specialized night vision equipment, was conducted in Indiana surrounding the Click It or Ticket 2006 safety belt mobilization activities. A pre- and a post-mobilization statewide direct observation survey was conducted at night coinciding with daytime safety belt use data collection conducted by the state of Indiana. Daytime and nighttime belt use rates were compared. RESULTS: The comparisons across the mobilization period revealed a significant increase during the day, but a significant decrease at night. Comparisons between daytime and nighttime belt use revealed no overall difference during the pre wave, but a significant difference during the post wave. Finally, many common daytime trends in belt use were also found at night, with the exception of the typical age and seating position effects. DISCUSSION: The mobilization activities had a positive effect on daytime belt use, but no effect on nighttime belt use, likely resulting in the differences between daytime and nighttime belt use observed during the post wave. IMPACT ON INDUSTRY: The findings of this study suggest that safety belt mobilizations implemented only during the day do not influence nighttime safety belt use. Changes to how these programs are implemented or additional programs specifically targeting belt use at night should be considered, along with continued monitoring of nighttime belt use.     

Microbiological and physical–chemical water quality of the rice fields in Sinos River’s basin, Southern Brazil

In this study, we evaluate spatial and temporal variations of the water’s quality used in rice fields. Every 15 days during the different phases of cultivation of the rice—vegetative, reproductive, and maturity—samples were collected from the main irrigation channel, from the surface water in the field, and from the excess-water drainage channel. The differences in the values of 13 variables were analyzed by the analysis of variance system and by the Principal Component Analysis (PCA) technique. The results demonstrate that the values observed for the presence of total coliforms, heat-tolerant coliforms, and pH were higher in the irrigation water and that the calcium and magnesium components were greater in the drainage water. The PCA results indicate that three groups of variance exist and that these three account for 77 % of the observed variances. The first principal component, (39 % of the variances), includes the variables pH, phosphorus, potassium, carbon, and turbidity; the second (28.1 %), calcium, magnesium, and conductivity; while the third accounts for only 9.9 % of the variation and incorporates the variable biological thermotolerant coliforms. The spatial pattern resulting from the distribution of the sampling locations as regards the first two principal components indicates a difference between the irrigation and drainage waters. The variables of the first and third items (except for the turbidity in the second component) reach higher values in the irrigation water, while the variables associated with the second component have higher values in the drainage water. The information provided is important for the analysis of the influence exercised by plantation management decisions on the microbiological, physical, and chemical quality of the water. The results confirm the ability of paddy rice field to filter out some of the chemicals and coliforms from the irrigation water as it passes through the agro ecosystem.     

Remobilization of polychlorinated biphenyls from sediment and its consequences for their transport in river waters

A laboratory experiment was performed to examine the remobilization of indicator polychlorinated biphenyls (iPCBs) from sediments and its results were applied to the real-world data for explaining the transport of PCBs in river. Seven PCB concentrations were determined in three series of model water–sediment systems (3 g of river sediment, three different volumes of distilled water (0.5, 0.25, and 0.15 ml), and 5 mg of biocide) after 11 days of incubation. Solid-phase extraction was used for separation of analytes from the aqueous phase and solvent extraction for isolation of analytes from the sediments, respectively. The extracts were analyzed for individual iPCB congeners using gas chromatography–mass spectrometry method. For each series of the experiment, the concentrations of PCBs in aqueous phase were similar. The average sediment/water partition coefficient value was 10⁴?l/kg. The solubility of individual PCB congeners in water did not influence the desorption of PCBs from the sediment. Although the dominant form of PCBs in a water–sediment system occurs as suspended and colloidal fractions, these compounds are transported mostly in a dissolved form. Suspended and colloidal matter is a major sink for PCBs in low-energy aquatic environments. In contrast, the dissolved PCBs are readily transported in running waters. The mobilization of PCBs from sediments to aqueous phase, with respect to their solubility in water, seems to be limited, thus reducing the risk of secondary pollution.     

Effects on hawthorn the year after simulated spray drift

This paper describes the effect of a herbicide applied at levels consistent with off target movement on hawthorn the year following exposure. In the experiment, metsulfuron-methyl was applied in five dosages to individual trees in seven different hawthorn hedgerows. Spraying was conducted both at the bud stage and at the early flowering. Five endpoints (i.e. leaves, buds, flowers, green berries and mature berries) were sampled and counted. All were significantly reduced with increasing exposure. Present day risk assessment of effects on non-target plants is therefore likely to overlook significant effects on perennial non-target plants in the spray drift zone due to the focus on results from short-term laboratory test studies. The significance of the present study is underlined by the fact that the effects observed were significant, even though other influential factors such as herbivory and differential pollination were not eliminated and that experiments were conducted in multiple locations.     

The strategy of fly-and-forage migration,illustrated for the osprey (<Emphasis Type="Italic">Pandion haliaetus</Emphasis>)

Migrating birds often alternate between flight steps, when distance is covered and energy consumed, and stopover periods, when energy reserves are restored. An alternative strategy is fly-and-forage migration, useful mainly for birds that hunt or locate their prey in flight, and thus, enables birds to combine foraging with covering migration distance. The favourability of this strategy in comparison with the traditional stopover strategy depends on costs of reduced effective travel speed and benefits of offsetting energy consumption during migration flights. Evaluating these cost-benefit effects, we predict that fly-and-forage migration is favourable under many conditions (increasing total migration speed), both as a pure strategy and in combination with stopover behaviour. We used the osprey (Pandion haliaetus) as test case for investigating the importance of this strategy during spring and autumn migration at a lake in southern Sweden. The majority, 78%, of passing ospreys behaved according to the fly-and-forage migration strategy by deviating from their migratory track to visit or forage at the lake, while 12% migrated past the lake without response, and 10% made stopovers at the lake. Foraging success of passing ospreys was almost as good as for birds on stopover. Timing of foraging demonstrated that the birds adopted a genuine fly-and-forage strategy rather than intensified foraging before and after the daily travelling period. We predict that fly-and-forage migration is widely used and important among many species besides the osprey, and the exploration of its occurrence and consequences will be a challenging task in the field of optimal migration.     

Rapid analysis of neonicotinoid insecticides in guttation drops of corn seedlings obtained from coated seeds

Regarding the hypothesis that neonicotinoid insecticides used for seed coating of agricultural crops - mainly corn, sunflower and seed rape - are related to the extensive death of honey bees, the phenomenon of corn seedling guttation has been recently considered as a possible route of exposure of bees to these systemic insecticides. In the present study, guttation drops of corn plants obtained from commercial seeds coated with thiamethoxam, clothianidin, imidacloprid and fipronil have been analyzed by an optimized fast UHPLC-DAD procedure showing excellent detection limits and accuracy, both adequate for the purpose. The young plants grown both in pots - in greenhouse - and in open field from coated seeds, produced guttation solutions containing high levels of the neonicotinoid insecticides (up to 346 mg L(-1) for imidacloprid, 102 mg L(-1) for clothianidin and 146 mg L(-1) for thiamethoxam). These concentration levels may represent lethal doses for bees that use guttation drops as a source of water. The neonicotinoid concentrations in guttation drops progressively decrease during the first 10-15 days after the emergence of the plant from the soil. Otherwise fipronil, which is a non-systemic phenylpyrazole insecticide, was never detected into guttation drops. Current results confirm that the physiological fluids of the corn plant can effectively transfer neonicotinoid insecticides from the seed onto the surface of the leaves, where guttation drops may expose bees and other insects to elevated doses of neurotoxic insecticides.     

Analysis of energy recovery potential using innovative technologies of waste gasification

In this paper, two alternative thermo-chemical processes for waste treatment were analysed: high temperature gasification and gasification associated to plasma process. The two processes were analysed from the thermodynamic point of view, trying to reconstruct two simplified models, using appropriate simulation tools and some support data from existing/planned plants, able to predict the energy recovery performances by process application. In order to carry out a comparative analysis, the same waste stream input was considered as input to the two models and the generated results were compared. The performances were compared with those that can be obtained from conventional combustion with energy recovery process by means of steam turbine cycle. Results are reported in terms of energy recovery performance indicators as overall energy efficiency, specific energy production per unit of mass of entering waste, primary energy source savings, specific carbon dioxide production.     

Improving dialogue among researchers,local and indigenous peoples and decision-makers to address issues of climate change in the North

Ambio - The Circumpolar North has been changing rapidly within the last decades, and the socioeconomic systems of the Eurasian Arctic and Siberia in particular have displayed the most dramatic...