Distribution and ecotoxicity of chlorotriazines in the Scheldt Estuary (B-Nl)

As part of the Endis-Risks project, the current study describes the occurrence of the chlorotriazine pesticides atrazine, simazine and terbutylazine in water, sediment and suspended matter in the Scheldt estuary (B-Nl) from 2002 to 2005 (3 samplings a year, 8 sampling points). Atrazine was found at the highest concentrations, varying from 10 to 736 ng/l in water and from 5 up to 10 ng/g in suspended matter. Simazine and terbutylazine were detected at lower concentrations. Traces of the targeted pesticides were also detected in sediments, but these were below the limit of quantification. As part of an ecotoxicological assessment, we studied the potential effect of atrazine on molting of Neomysis integer (Crustacea:Mysidacea), a resident invertebrate of the Scheldt Estuary and a proposed test organism for the evaluation of endocrine disruption. Following chronic exposure ( approximately 3 weeks), atrazine did not significantly affect mysid molting at environmentally relevant concentrations (up to 1 microg/l).     

Safety climate dimensions,leader–member exchange,and organizational support as predictors of upward safety communication in a sample of rail industry workers

The freedom employees feel to communicate safety concerns with their supervisors, termed upward safety communication, has been shown to be related to adverse safety events (Hofmann and Morgeson, 1999). Research to date has demonstrated that good supervisor–employee relationships (leader–member exchange), a sense that the organization values an employee (perceived organizational support) and safety climate (including perceived management attitudes toward safety, job demands interfering with safety, and pressure from coworkers to behave safely) all contribute to employees’ comfort in bringing up safety issues with their supervisors. However, little is known about which specific dimensions of safety climate are most predictive of upward safety communication. Using a sample of 548 railway workers, we found that when all factors were considered simultaneously using dominance analysis, the dominant factor predicting upward safety communication was perceived management attitudes toward safety, followed by job demands interfering with safety and then leader–member exchange. Implications for research and practice are discussed.     

Citizen board issues and local newspaper coverage of risk,remediation, and environmental management: Six U.S. nuclear weapons facilities

We examined site‐specific advisory board (SSAB) minutes and local newspaper coverage of the Fernald, Hanford, Idaho, Oak Ridge, Rocky Flats, and Savannah River sites of the U.S. Department of Energy (US DOE) in order to determine the importance of risk‐related issues related to remediation and other forms of environmental management. About one‐third of SSAB issues were risk‐related, and these were disproportionately major issues at meetings. The media focused on risks associated with remediation and other forms of waste management. The analysis implies that contractors and government officials need to establish and maintain communications with advisory panels and accentuate these contacts well in advance of contemplated new actions. © 2008 Wiley Periodicals, Inc.     

Management commitment to safety as organizational support: relationships with non-safety outcomes in wood manufacturing employees

INTRODUCTION: Employee perceptions of management commitment to safety are known to influence important safety-related outcomes. However, little work has been conducted to explore non-safety-related outcomes resulting from a commitment to safety. METHOD: Employee-level outcomes critical to the effective functioning of an organization, including attitudes such as job satisfaction and commitment to the organization, were included on surveys given to 641 hourly production employees at three wood products manufacturing facilities. Participants' were asked about perceptions of management commitment to safety and job-related variables such as perceived dangerousness of their position, organizational commitment, and withdrawal behaviors. Supervisors also rated the performance of each of their hourly subordinates. RESULTS: Results suggest that employee outcomes differ based on perceptions of management's commitment to safety. Specifically, management commitment to safety was positively related to job satisfaction, organizational commitment, and job-related performance. We also found a negative relationship between commitment to safety and employee withdrawal behaviors. CONCLUSIONS: Our results suggest that increasing employee perceptions of management's personal concern for employee well-being through a dedication to safety will result in positive outcomes beyond improved safety performance. These results also imply that there is a type of social exchange between employees and management that may affect employees similarly to perceived organizational support. IMPACT ON INDUSTRY: Results further reinforce the value of a commitment to safety by a firm's management. Organizations with a strong commitment to safety may enjoy not only a reduction in safety-related events but also increases in desirable employee attitudes and behaviors.     

Do pronghorn mothers reveal the locations of their hidden fawns?

Summary Success of the hider strategy in ungulates depends, in part, on the mother's ability to minimize information she transmits about her young's hiding place while remaining close enough to distract or drive away a predator. We predicted that pronghorn (Antilocapra americana) mothers should: (1) maintain minimum distances from their hidden fawns sufficient to cause the expected energy gain for a ground predator, systematically searching around the mother, to fall below that expected when searching for some other prey; (2) orient the axes of either head or trunk towald the hidden fawn no more frequently than would be expected by chance; (3) schedule behavior so that no activity is more likely than another to occur when a visit to the hidden fawn is imminent. At the National Bison Range, where coyote (Canis latrans) predation on pronghorn fawns is frequent, pronghorn mothers conform to predictions (1) and (3), but not (2). Within the first 10% of their time away from fawns, mothers reached an average distance of 70.4 m from their fawns' biding places and remained at that distance until 95% of their time away was clapsed. At this mother-fawn distance a coyote, using the mother's position to begin a systematic search for the fawn, and searching at a rate of 4 m²/s, would gain energy at a lower rate than it would hunting ground squirrels (Spermophilus columbianus). Mothers pointed both head and trunk toward their hidden fawns more frequently than would be expected by chance and coyotes, able to use this information to establish a 90° quadrant to search, could expect rates of gain higher than those obtainable in 360° search. Mothers especially tended to orient both head and trunk toward their fawns when standing or moving. Coyotes that begin a 90° search based on the mother's head or trunk position only when mothers were standing or moving, could expect rates of energy gain almost double those expected in 360° search or ground squirrel hunting. Maternal activities (stand, feed, recline, or move) were distributed evenly across all mother-fawn distances and across percent total time away from the fawn. Thus, activity was not a good predictor of a mother's likelihood of soon returning to her fawn. Mothers also remained away from their fawns long enough to cause the expected rate of energy gain for a coyote hiding and watching for the mother's return to the fawn to fall well below the rate expected for searching or ground squirrel hunting.     

Chemical contaminants in juvenile gray whales (Eschrichtius robustus) from a subsistence harvest in Arctic feeding grounds

Gray whales are coastal migratory baleen whales that are benthic feeders. Most of their feeding takes place in the northern Pacific Ocean with opportunistic feeding taking place during their migrations and residence on the breeding grounds. The concentrations of organochlorines and trace elements were determined in tissues and stomach contents of juvenile gray whales that were taken on their Arctic feeding grounds in the western Bering Sea during a Russian subsistence harvest. These concentrations were compared to previously published data for contaminants in gray whales that stranded along the west coast of the US during their northbound migration. Feeding in coastal waters during their migrations may present a risk of exposure to toxic chemicals in some regions. The mean concentration (standard error of the mean, SEM) of sigmaPCBs [1400 (130) ng/g, lipid weight] in the blubber of juvenile subsistence whales was significantly lower than the mean level [27,000 (11,000) ng/g, lipid weight] reported previously in juvenile gray whales that stranded in waters off the west coast of the US. Aluminum in stomach contents of the subsistence whales was high compared to other marine mammal species, which is consistent with the ingestion of sediment during feeding. Furthermore, the concentrations of potentially toxic chemicals in tissues were relatively low when compared to the concentrations in tissues of other marine mammals feeding at higher trophic levels. These chemical contaminant data for the subsistence gray whales substantially increase the information available for presumably healthy animals.     

Ambient level volatile organic compound (VOC) monitoring using solid adsorbents--recent US EPA studies

Ambient air spiked with 1-10 ppbv concentrations of 41 toxic volatile organic compounds (VOCs) listed in US Environmental Protection Agency (EPA) Compendium Method TO-14A was monitored using solid sorbents for sample collection and a Varian Saturn 2000 ion trap mass spectrometer for analysis. The adsorbent was a combination of graphitic carbon and a Carboxen-type carbon molecular sieve. The method detection limits (MDLs) for 11 samples were typically 0.5 parts per billion by volume (ppbv) and lower except for bromomethane and chloromethane, both of which exhibited breakthrough. Thirty-day sample storage on the sorbents resulted in less than a 20% change for most compounds, and water management was required for humid samples to avoid major anomalous decreases in response during analyses. The adsorbent-based system, a system using canister-based monitoring, and a semi-continuous automated GC/MS (autoGC) monitoring system with a Tenax GR/Carbotrap B/Carbosieve S-III adsorbent preconcentrator were compared using spiked ozone concentrations as a variable. In this comparison, the target compounds included a number of n-aldehydes as well as those listed in TO-14A. The effects of ozone on the TO-14A compounds were relatively minor with the exception of negative artifacts noted for styrene and 1,1,2,2-tetrachloroethane. However, a small, systematic decrease in response was evident for a number of aromatic VOCs and 1,1,2,2-tetrachloroethane when ozone was increased from 50 to 300 ppbv. Method averages for multiple runs under the same conditions were typically within +0.25 ppbv of their mean for most compounds. For n-aldehydes, strong positive artifacts using the autoGC preconcentrator and strong negative artifacts for the canister-based and carbon sorbent approaches caused major disagreement among methods. These artifacts were mostly eliminated by using MnO2 ozone scrubbers, although loss of the n-aldehydes for all methods occurred after a single sample collection of 1 h duration, apparently due to the interaction of the n-aldehydes and products of the O3, MnO2 reaction on the scrubber.