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Nagar R.,Weiss Associates | Sarkar D.,Montclair State University | Makris K.C.,Cyprus International Institute for the Environment and Public Health | Datta R.,Michigan Technological University
International Journal of Environmental Science and Technology | Year: 2013

Previous studies in our laboratory have demonstrated that drinking-water treatment residuals are effective sorbents of arsenic V. However, the effect of soil solution chemistry on arsenic V sorption by drinking-water treatment residuals-amended soils remains to be explored. The current study uses a batch incubation experimental set up to evaluate the effect of soil solution pH, competing ligands, and complexing metal on arsenic V sorption by a sandy soil (Immokalee series) amended with two rates (25 and 50 g kg-1) of aluminum and iron-based drinking-water treatment residuals. Experiments were conducted at three initial arsenic loads (125, 1,875, 3,750 mg kg-1) and a constant solid: solution ratio of 200 g L-1. An optimum equilibration time of 8 days, obtained from kinetic studies, was utilized for sorption experiments with both aluminum and iron drinking-water treatment residual-amended soil. Presence of phosphate decreased arsenic V sorption by both aluminum and iron drinking-water treatment residual amended soils, with a strong dependence on pH, drinking-water treatment residual types, drinking-water treatment residual application rates, and phosphate concentrations. Addition of sulfate had no effect on arsenic V sorption by aluminum or iron drinking-water treatment residual-amended soil. A complementing effect of calcium on arsenic V sorption was observed at higher pH. Results elucidating the effect of soil solution chemistry on the arsenic V sorption will be helpful in calibrating drinking-water treatment residual as a sorbent for remediation of arsenic-contaminated soils. © 2012 CEERS, IAU. Source

Dionisio K.L.,Harvard University | Rooney M.S.,Harvard Initiative for Global Health | Arku R.E.,Cyprus International Institute for the Environment and Public Health | Arku R.E.,University of Ghana | And 6 more authors.
Environmental Health Perspectives | Year: 2010

Background: Sources of air pollution in developing country cities include transportation and industrial pollution, biomass and coal fuel use, and resuspended dust from unpaved roads. Objectives: Our goal was to understand within-neighborhood spatial variability of particulate matter (PM) in communities of varying socioeconomic status (SES) in Accra, Ghana, and to quantify the effects of nearby sources on local PM concentration. Methods: We conducted 1 week of morning and afternoon mobile and stationary air pollution measurements in four study neighborhoods. PM with aerodynamic diameters ≤ 2.5 μm (PM2.5) and ≤ 10 μm (PM10) was measured continuously, with matched global positioning system coordinates; detailed data on local sources were collected at periodic stops. The effects of nearby sources on local PM were estimated using linear mixed-effects models. Results: In our measurement campaign, the geometric means of PM2.5 and PM10 along the mobile monitoring path were 21 and 49 μg/m3, respectively, in the neighborhood with highest SES and 39 and 96 μg/m3, respectively, in the neighborhood with lowest SES and highest population density. PM2.5 and PM10 were as high as 200 and 400 μg/m3, respectively, in some segments of the path. After adjusting for other factors, the factors that had the largest effects on local PM pollution were nearby wood and charcoal stoves, congested and heavy traffic, loose dirt road surface, and trash burning. Conclusions: Biomass fuels, transportation, and unpaved roads may be important determinants of local PM variation in Accra neighborhoods. If confirmed by additional or supporting data, the results demonstrate the need for effective and equitable interventions and policies that reduce the impacts of traffic and biomass pollution. Source

Arvaniti F.,Agricultural University of Athens | Priftis K.N.,Penteli Childrens Hospital | Papadimitriou A.,National and Kapodistrian University of Athens | Yiallouros P.,Cyprus International Institute for the Environment and Public Health | And 3 more authors.
Journal of the American Dietetic Association | Year: 2011

Background: Salty-snack consumption, as well as the amount of time children spend watching television or playing video games, have been implicated in the development of asthma; however, results are still conflicting. Objective: The aim of this work was to evaluate the association of salty-snack eating and television/video-game viewing with childhood asthma symptoms. Design: Cross-sectional study. Settings: Seven hundred children (323 male), 10 to 12 years old, from 18 schools located in the greater area of Athens were enrolled. Children and their parents completed questionnaires, which evaluated, among other things, dietary habits. Adherence to the Mediterranean diet was evaluated using the KIDMED (Mediterranean Diet Quality Index for Children and Adolescents) score. Statistical analysis: The association of children's characteristics with asthma symptoms was performed by calculating the odds ratios and corresponding 95% confidence intervals. Results: Overall lifetime prevalence of asthma symptoms was 23.7% (27.6% boys, 20.4% girls; P=0.03). Forty-eight percent of children reported salty-snack consumption (≥1 times/week). Salty-snack consumption was positively associated with the hours of television/video-game viewing (P=0.04) and inversely with the KIDMED score (P=0.02). Consumption of salty snacks (>3 times/week vs never/rare) was associated with a 4.8-times higher likelihood of having asthma symptoms (95% confidence interval: 1.50 to 15.8), irrespective of potential confounders. The associations of salty-snack eating and asthma symptoms were more prominent in children who watched television or played video games >2 hours/day. In addition, adherence to the Mediterranean diet was inversely associated with the likelihood of asthma symptoms. Conclusions: Unhealthy lifestyle behaviors, such as salty-snack eating and television/video-game viewing were strongly associated with the presence of asthma symptoms. Future interventions and public health messages should be focused on changing these behaviors from the early stages of life. © 2011 American Dietetic Association. Source

Rice G.E.,Harvard University | Hammitt J.K.,Center for Risk Analysis | Evans J.S.,Harvard University | Evans J.S.,Cyprus International Institute for the Environment and Public Health
Environmental Science and Technology | Year: 2010

We developed a probabilistic model to characterize the plausible distribution of health and economic benefits that would accrue to the U.S. population following reduction of methyl mercury (MeHg) exposure. MeHg, a known human developmental neurotoxicant, may increase fatal heart attack risks. Model parameters reflect current understanding of the relationships between MeHg intake, health risks, and societal valuation of these risks. The expected monetary value of the annual health benefits generated by a 10% reduction in U.S. population exposure to MeHg for one year is $860 million; 80% of this is associated with reductions in fatal heart attacks and the remainder with IQ gains. The plausible distribution of the benefits is quite broad with 5th and 95th percentile estimates of approximately $50 million and $3.5 billion, respectively. The largest source of uncertainty is whether epidemiological associations between MeHg exposure and fatal heart attacks reflect causality. The next largest sources of uncertainty concern the slope of the relationship between maternal MeHg exposure and reduced intelligence among children and whether this relationship exhibits a threshold. Our analysis suggests that the possible causal relationship between MeHg exposure and fatal heart attacks should be better characterized, using additional epidemiological studies and formally elicited expert judgment. © 2010 American Chemical Society. Source

Dionisio K.L.,Harvard University | Arku R.E.,University of Ghana | Arku R.E.,Cyprus International Institute for the Environment and Public Health | Hughes A.F.,University of Ghana | And 5 more authors.
Environmental Science and Technology | Year: 2010

This study examined the spatial, socioeconomic status (SES), and temporal patterns of ambient air pollution in Accra, Ghana. Over 22 months, integrated and continuous rooftop particulate matter (PM) monitors were placed at a total of 11 residential or roadside monitoring sites in four neighborhoods of varying SES and biomass fuel use. PM concentrations were highest in late December and January, due to dust blown from the Sahara. Excluding this period, annual PM2.5 ranged from 39 to 53μg/m3 at roadside sites and 30 to 70 μg/m3 at residential sites; mean annual PM10 ranged from 80 to 108 μg/m3 at roadside sites and 57 to 106 μg/m3 at residential sites. The low-income and densely populated neighborhood of Jamestown/Ushertown had the single highest residential PM concentration. There was less difference across traffic sites. Daily PM increased at all sites at daybreak, followed by a mid-day peak at some sites, and a more spread-out evening peak at all sites. Average carbon monoxide concentrations at different sites and seasons ranged from 7 to 55 ppm, and were generally lower at residential sites than at traffic sites. The results show that PM in these four neighborhoods is substantially higher than the WHO Air Quality Guidelines and in some cases even higher than the WHO Interim Target 1, with the highest pollution in the poorest neighborhood. © 2010 American Chemical Society. Source

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