Contributions of global and regional sources to mercury deposition in New York State

A modeling system that includes a global chemical transport model (CTM) and a nested continental CTM (TEAM) was used to simulate the atmospheric transport, transformations and deposition of mercury (Hg). Three scenarios were used: (1) a nominal scenario, (2) a scenario conducive to local deposition and (3) a scenario conducive to long-range transport. Deposition fluxes of Hg were analyzed at three receptor locations in New York State. For the nominal scenario, the anthropogenic emission sources (including re-emission of deposited Hg) in New York State, the rest of the contiguous United States, Asia, Europe, and Canada contributed 11-1, 25-9, 13-19, 5-7, and 2-5%, respectively to total Hg deposition at these three receptors. Natural sources contributed 16-4%. The results from the local deposition and long-range transport scenarios varied only slightly from these results. However, there are still uncertainties in our understanding of the atmospheric chemistry of Hg that are likely to affect these estimates of local, regional and global contributions. Comparison of model simulation results with data from the Mercury Deposition Network suggests that local and regional contributions may currently be overestimated.     

Nonylphenolic compounds in drinking and surface waters downstream of treated textile and pulp and paper effluents: a survey and preliminary assessment of their potential effects on public health and aquatic life

Eleven drinking water treatment plants, located downstream of textile plants or pulp and paper mills, have been sampled monthly during a year for the analysis of 17 nonylphenol ethoxylates (NP1-17EO) and two nonylphenoxycarboxylic acids (NP1-2EC). At all but one plant, results in the drinking water, for the sum of these 19 substances, range between below detection levels and 6.7 microg/l. Annual means are between 0.02 and 2.8 microg/l. At the other plant, the yearly average concentration is 10.4 microg/l and the monthly maximum is 43.3 microg/l. In the surface (pre-treatment) water, the annual mean concentrations of the 11 plants range between 0.14 and 17.8 microg/l and the recorded instantaneous maximum is 55.3 microg/l. According to Canadian health authorities, drinking water is a negligible route of human exposure to nonylphenolic compounds, even at the highest concentrations found in this study. After transformation of the data into nonylphenol equivalents, about 20% of the surface water samples exceed the Canadian 1 microg/l nonylphenol water quality guideline for the protection of aquatic life. Some results also exceed Québec's 6 microg/l nonylphenol guideline. The efficiency of the plants in removing nonylphenolic compounds from drinking water is highly variable, ranging from 11% to 99%.     

Organizations and supervisors as sources of support and targets of commitment: a longitudinal study

The main objective of this study was to examine the relationship between perceived support and affective commitment, and the linkages between these constructs and some of their common antecedents and consequences. More precisely, using a sample of 238 employees, we conducted a longitudinal study to examine the linkages between the favorableness of intrinsically and extrinsically satisfying job conditions, perceived organizational support, perceived supervisor support, affective commitment to the organization and supervisor, and turnover. Affective commitment to the supervisor was found to completely mediate the effect of perceived supervisor support on turnover, whereas neither perceived organizational support nor organizational affective commitment were significantly related to turnover. Perceived organizational support partially mediated the effect of favorable intrinsically satisfying job conditions on organizational affective commitment and fully mediated the effect of extrinsically satisfying job conditions on organizational affective commitment. Finally, perceived supervisor support totally mediated the effect of favorable intrinsically satisfying job conditions on affective commitment to the supervisor. As a whole, findings suggest that exchange relationships between employees and their supervisors should be further investigated in future turnover research. Copyright © 2003 John Wiley & Sons, Ltd.     

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