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51.
This study aimed to evaluate the sediment quality in the estuarine protected area known as Cananéia-Iguape-Peruíbe (CIP-PA), located on the southeastern coast of Brazil. The study was designed considering possible negative effects induced by the city of Cananéia on the sediment quality of surrounding areas. This evaluation was performed using chemical and ecotoxicological analyses. Sediments were predominantly sandy, with low CaCO3 contents. Amounts of organic matter varied, but higher contents occurred closer to the city, as well as did Fe and Total Recoverable Oils and Greases (TROGs) concentrations. Contamination by Cd and Cu was revealed in some samples, while concentrations of Zn were considered low. Chronic toxicity was detected in all tested sediments and acute toxicity occurred only in sediments collected near the city. The principal component analysis (PCA) revealed an association among Cd, Cu, Fe, TROG, fines, organic matter, CaCO3, and chronic toxicity, whereas acute toxicity was found to be associated with Zn and mud. However, because Zn levels were low, acute toxicity was likely due to a contaminant that was not measured. Results show that there is a broad area within the CIP-PA that is under the influence of mining activities (chronic toxicity, moderate contamination by metals), whereas poorer conditions occur closer to Cananéia (acute toxicity); thus, the urban area seems to constitute a relevant source of contaminants for the estuarine complex. These results show that contamination is already capable of producing risks for the local aquatic biota, which suggests that the CIP-PA effectiveness in protecting estuarine biota may be threatened.  相似文献   
52.
While it is known that the ingestion of indoor dust contributes substantially to human exposure to the recently restricted polybrominated diphenyl ethers (PBDEs), the situation for one class of potential replacements, i.e. organophosphate esters (OPEs), used in a variety of applications including as flame retardants has yet to be fully characterised. In this study, surface dust from twelve different cars from various locations throughout Germany were analysed for eight OPEs, decabromodiphenyl ethane (DBDPE), and eight PBDEs. In five cars, tris-(1,3-dichloro-2-propyl) phosphate (TDCPP) was the dominant compound with concentrations up to 620 μg g(-1) dust. High concentrations of tri-cresyl phosphate (TCP) (up to 150 μg g(-1)) were also detected in two samples of car dust. Dust from ten offices in the same building in Ludwigsburg, Germany was also analysed. In these samples, tri (2-butoxyethyl) phosphate (TBEP) predominated with an average concentration of 7.0 μg g(-1) dust, followed by tris (1-chloro-2-propyl) phosphate (TCPP) at 3.0 μg g(-1) and triphenyl phosphate (TPhP) at 2.5 μg g(-1) dust. Although caution must be exercised given the relatively small database reported here; this study provides evidence that cars and offices from Germany are significantly more contaminated with OPEs than PBDEs. Average concentrations of ΣOPEs were ten times higher in car than in office dust. This is the first study to provide data on a wide range of OPE concentrations in German indoor dust samples.  相似文献   
53.
The extent of correlation in polycyclic aromatic hydrocarbon (PAH) concentration data obtained by the UK PAH Monitoring and Analysis Air Quality Network from March 2008 to November 2010 has been assessed. Application of principal component analysis (PCA) to the dataset has revealed that the concentrations of the vast majority of PAHs are very highly correlated. The use of diagnostic PAH ratios (including a new benzo[b]naph[2,1-d]thiophene/benzo[a]pyrene diagnostic ratio), and a novel 'combined diagnostic ratio - PCA' approach has revealed information about the main sources of PAH at individual Network sites, allowing the sites to be grouped in terms of those influenced by solid fuel use, industry and traffic, and those of an urban or rural nature. Solid fuel use has also been delineated from other fuel burning. Conclusions are drawn about a number of UK PAH Network sites - four sites are shown to be influenced significantly by solid fuel use, and the sites in South Wales and at London Marylebone Road are found to be located in distinct and unusual PAH pollution climates - the identification of a unique PAH pollution climate in South Wales is a key and novel conclusion of the work.  相似文献   
54.
Objective: This study evaluated the effectiveness of a series of 1-year multifaceted school-based programs aimed at increasing booster seat use among urban children 4–7 years of age in economically disadvantaged areas.

Methods: During 4 consecutive school years, 2011–2015, the Give Kids a Boost (GKB) program was implemented in a total of 8 schools with similar demographics in Dallas County. Observational surveys were conducted at project schools before project implementation (P0), 1–4 weeks after the completion of project implementation (P1), and 4–5 months later (P2). Changes in booster seat use for the 3 time periods were compared for the 8 project and 14 comparison schools that received no intervention using a nonrandomized trial process.

The intervention included (1) train-the-trainer sessions with teachers and parents; (2) presentations about booster seat safety; (3) tailored communication to parents; (4) distribution of fact sheets/resources; (5) walk-around education; and (6) booster seat inspections.

The association between the GKB intervention and proper booster seat use was determined initially using univariate analysis. The association was also estimated using a generalized linear mixed model predicting a binomial outcome (booster seat use) for those aged 4 to 7 years, adjusted for child-level variables (age, sex, race/ethnicity) and car-level variables (vehicle type). The model incorporated the effects of clustering by site and by collection date to account for the possibility of repeated sampling.

Results: In the 8 project schools, booster seat use for children 4–7 years of age increased an average of 20.9 percentage points between P0 and P1 (P0 = 4.8%, P1 = 25.7%; odds ratio [OR] = 6.9; 95% confidence interval [CI], 5.5, 8.7; P < .001) and remained at that level in the P2 time period (P2 = 25.7%; P < .001, for P0 vs. P2) in the univariate analysis. The 14 comparison schools had minimal change in booster seat use. The multivariable model showed that children at the project schools were significantly more likely to be properly restrained in a booster seat after the intervention (OR = 2.7; 95% CI, 2.2, 3.3) compared to the P0 time period and compared to the comparison schools.

Conclusion: Despite study limitations, the GKB program was positively associated with an increase in proper booster seat use for children 4–7 years of age in school settings among diverse populations in economically disadvantaged areas. These increases persisted into the following school year in a majority of the project schools. The GKB model may be a replicable strategy to increase booster seat use among school-age children in similar urban settings.  相似文献   

55.
ABSTRACT

Objective: Alcohol-impaired driving presents a continued risk for traffic safety and results in a significant proportion of fatalities on the roadway. We examined how alcohol at a 0.05% blood alcohol concentration (BAC) compares to 0.10% BAC (above the current U.S. legal limit) in terms of impact on driving performance.

Methods: Utilizing a within-subjects design, we recruited 108 healthy experienced drivers who were moderate to heavy drinkers. In a double-blind, placebo-controlled crossover design, we administered placebo and alcohol at the 0.05% and 0.10% BAC levels in a standardized simulated driving protocol. Drives occurred on the descending limb of the blood alcohol curve. This analysis focuses on the urban portion of the drive

Results: The study observed clear differences in performance for lateral and longitudinal driving performance and glance behavior. Variability in lane keeping and average speed increased with BAC level, with degraded performance observed at 0.05% BAC. The frequency of lane departures and percentage of time focused on the forward roadway at 0.05% BAC did not differ from placebo but differed from the 0.10% BAC level.

Conclusions: Overall, our results show that there is degraded performance in the urban driving environment and that much of that begins at or below the 0.05% BAC level.  相似文献   
56.
Jonathan M. H. Green  Gemma R. Cranston  William J. Sutherland  Hannah R. Tranter  Sarah J. Bell  Tim G. Benton  Eva Blixt  Colm Bowe  Sarah Broadley  Andrew Brown  Chris Brown  Neil Burns  David Butler  Hannah Collins  Helen Crowley  Justin DeKoszmovszky  Les G. Firbank  Brett Fulford  Toby A. Gardner  Rosemary S. Hails  Sharla Halvorson  Michael Jack  Ben Kerrison  Lenny S. C. Koh  Steven C. Lang  Emily J. McKenzie  Pablo Monsivais  Timothy O’Riordan  Jeremy Osborn  Stephen Oswald  Emma Price Thomas  David Raffaelli  Belinda Reyers  Jagjit S. Srai  Bernardo B. N. Strassburg  David Webster  Ruth Welters  Gail Whiteman  James Wilsdon  Bhaskar Vira 《Sustainability Science》2017,12(2):319-331
Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the ‘nexus’ of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation.  相似文献   
57.
This mixed-method case study of environmental communication best practices in Louisiana, USA, identifies trends and approaches as informed by environmental psychology. The results provide key insights for environmental communicators, especially communicators in coastal regions. In-depth interviews with both environmental psychologists and environmental communicators showed that both groups emphasized knowing the audience, telling local stories, building relationships with target audiences and targeted messaging. Both psychologists and communicators also frequently mentioned general messaging concerns of source credibility, avoiding controversial terms and talking about issues, impacts and solutions to which the target audience can relate. A representative survey revealed that Louisiana residents are most interested in hearing about how environmental issues such as climate change, coastal land loss and flooding are affecting their own communities. This finding supports the idea that environmental communicators could do a better job tapping into strong place attachment and sense of community among coastal residents to promote action.  相似文献   
58.
Laboratory and field demonstration studies were conducted to assess the efficacy of enhanced biological reduction of 1,2,3‐trichloropropane (TCP) in groundwater. Laboratory studies evaluated the effects of pH and initial TCP concentrations on TCP reduction and the activity of a microbial inoculum containing Dehalogenimonas (Dhg). Laboratory results showed successful reduction at a pH of 5 to 9 with optimal reduction at 7 to 9 and at initial TCP concentrations ranging from 10 to over 10,000 micrograms per liter (μg/L). Based on findings from the laboratory study, the effects of TCP concentration, geochemical conditions, and amendment concentration on bioremediation efficacy were investigated during a field demonstration at a site with relatively low initial concentrations of TCP (< 2 μg/L). The field demonstration included injection of emulsified vegetable oil (EVO) and lactate as a carbon substrate for biostimulation, followed by bioaugmentation using the microbial inoculum containing Dhg. Post‐injection performance monitoring demonstrated reduction of TCP to below laboratory detection limits (< 0.005 μg/L) after an initial lag period of approximately six months following injections. TCP reduction was accompanied by generation of the degradation byproduct propene. A marginal increase in TCP concentrations, potentially due to an influx of upgradient aerobic groundwater containing TCP, was observed eight months after injections thereby demonstrating the sensitivity of this bioaugmentation application to changes in geochemical parameters. Despite this marginal increase, performance monitoring results indicate continued TCP biodegradation 15 months after implementation of the injection program. This demonstration suggests that enhanced biodegradation of TCP by combining biostimulation and bioaugmentation may be a promising solution to the challenges associated with remediation of TCP, even when present at low part per billion concentrations in groundwater.  相似文献   
59.
Differential white blood cell counting was performed on blood from the fish species Oreochromis niloticus and was used as an in situ indicator of the species’ exposure to contamination. Ten young fish were collected in an area influenced by the discharge of effluents and from a fish farm (control group). The fish were anesthetized and caudal puncture was used to collect the blood. Differential white blood cell counting was performed, as well as the counting of total leukocytes and thrombocytes (in 2000 cells). Physicochemical parameters of the water from both sites were analyzed. The water from the polluted area was found to have high conductivity and low levels of dissolved oxygen, factors that indicate poor environmental quality. Fish collected from the polluted site presented higher percentages of eosinophils and monocytes and fewer thrombocytes because of exposure to pollution and hypoxic conditions. The differential white blood cell count represents a suitable biomarker of environmental health and provides a tool for biomonitoring water quality.  相似文献   
60.
Although trace concentrations of ibuprofen (IBP) have been detected in diverse water bodies, there is currently insufficient information on the potentially deleterious effects of this xenobiotic. The present study aimed to determine whether IBP induces oxidative stress in brain, liver, gill, and blood of the common carp Cyprinus carpio. To this end, the median lethal concentration at 96 h (96-h LC50) was determined and the lowest observed adverse effect level was established. Carp were exposed to the latter concentration (17.6 mg L?1) for 12, 24, 48, 72, and 96 h, and the following biomarkers were evaluated: lipid peroxidation (LPX) and activity of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase. Results indicated that LPX and antioxidant enzymes’ activity increased significantly (p?<?0.05) with respect to the control group in liver, gill, and blood, while no significant differences occurred in brain. In conclusion, IBP induced oxidative stress on C. carpio, the liver being the organ most affected by this damage.  相似文献   
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