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Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions
2014
Hu, Xin | Sun, Yuanyuan | Ding, Zhuhong | Zhang, Yun | Wu, Jichun | Lian, Hongzhen | Wang, Tijian
Lead levels and isotopic compositions in atmospheric particles (TSP and PM2.5), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM2.5 are significantly higher than them in the surface soil and street dust (p < 0.05). The enrichment factor using the mass ratio of lead to the major crustal elements (Al, Sr, Ti and Fe) indicates significant lead enrichment in atmospheric particles. The plots of 206Pb/207Pb vs.208Pb/206Pb and 206Pb/207Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM2.5) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM2.5), while the deposition of airborne lead is an important lead source for urban surface soil.
Show more [+] Less [-]Air pollution effects on fetal and child development: A cohort comparison in China
2014
Tang, Deliang | Li, Ting Yu | Chow, Judith C. | Kulkarni, Sanasi U. | Watson, John G. | Ho, Steven Sai Hang | Quan, Zhang Y. | Qu, L.R. | Perera, Frederica
In Tongliang, China, a coal-fired power plant was the major pollution source until its shutdown in 2004. We enrolled two cohorts of nonsmoking women and their newborns before and after the shutdown to examine the relationship between prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) and fetal and child growth and development. PAHs were used to measure exposure to air pollution generated by the power plant. Using PAH–DNA adduct levels as biomarkers for the biologically effective dose of PAH exposure, we examined whether PAH–DNA adduct levels were associated with birth outcome, growth rate, and neurodevelopment. Head circumference was greater in children of the second cohort, compared with the first (p = 0.001), consistent with significantly reduced levels of cord blood PAH–DNA adducts in cohort II (p < 0.001) and reduced levels of ambient PAHs (p = 0.01).
Show more [+] Less [-]Source apportionment of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons by a PMF receptor model. Assessment of potential risk for human health
2014
Callén, María Soledad | Iturmendi, Amaia | López, José Manuel
One year sampling (2011–2012) campaign of airborne PM2.5-bound PAH was performed in Zaragoza, Spain. A source apportionment of total PAH by Positive Matrix Factorization (PMF) was applied in order to quantify potential PAH pollution sources.Four sources were apportioned: coal combustion, vehicular emissions, stationary emissions and unburned/evaporative emissions. Although Directive 2004/107/EC was fulfilled regarding benzo(a)pyrene (BaP), episodes exceeding the limit value of PM2.5 according to Directive 2008/50/EC were found. These episodes of high negative potential for human health were studied, obtaining a different pattern for the exceedances of PM2.5 and the lower assessment threshold of BaP (LATBaP). In both cases, stationary emissions contributed majority to total PAH. Lifetime cancer risk exceeded the unit risk recommended by the World Health Organization for those episodes exceeding the LATBaP and the PM2.5 exceedances for the warm season. For the cold season, the risk was higher for the LATBaP than for the PM2.5 exceedances.
Show more [+] Less [-]Surface water geochemical and isotopic variations in an area of accelerating Marcellus Shale gas development
2014
Pelak, Adam J. | Sharma, Shikha
Water samples were collected from 50 streams in an area of accelerating shale gas development in the eastern U.S.A. The geochemical/isotopic characteristics show no correlation with the five categories of Marcellus Shale production. The sub-watersheds with the greatest density of Marcellus Shale development have also undergone extensive coal mining. Hence, geochemical/isotopic compositions were used to understand sources of salinity and effects of coal mining and shale gas development in the area. The data indicates that while some streams appear to be impacted by mine drainage; none appear to have received sustained contribution from deep brines or produced waters associated with shale gas production. However, it is important to note that our interpretations are based on one time synoptic base flow sampling of a few sampling stations and hence do account potential intermittent changes in chemistry that may result from major/minor spills or specific mine discharges on the surface water chemistry.
Show more [+] Less [-]An urgent need for an EPA standard for disposal of coal ash
2014
Lemly, A Dennis
EPA, the White House, and electric utilities are stalled in a struggle over a proposed new rule on coal ash disposal. Although this rule is long overdue, EPA now stands on the cusp of bringing forward a landmark decision that could benefit aquatic resources in the USA for decades to come and also set an important regulatory leadership example for the international community to follow. However, multi-million dollar wildlife losses are continuing to pile up as things stall in Washington. In this commentary I use a newly reported example, Wildlife Damage Case 23, to further illustrate serious flaws in the National Pollutant Discharge Elimination System that EPA's new rule can address. Case 23 provides additional impetus for EPA and the White House to move swiftly and decisively to end surface impoundment disposal of coal ash and the associated toxic impacts to wildlife.
Show more [+] Less [-]Maternal transfer and embryonic assimilation of trace elements in freshwater turtles after remediation of a coal fly-ash spill
2014
Van Dyke, James U. | Steen, David A. | Jackson, Brian P. | Hopkins, William A.
Oviparous vertebrates maternally transfer elements to their offspring during egg production. Maternal transfer occurs because elements mimic, or are incorporated into, nutrients allocated to eggs, but likely differs among species depending on the quantities of specific nutrients allocated to eggs. Developing embryos are often assumed to assimilate all of the elements allocated to eggs, but this assumption has rarely been tested. We tested the hypothesis that maternal transfer and embryonic assimilation of trace elements differed between two species of freshwater turtles exposed to a recently-remediated coal fly-ash spill. Sternotherus odoratus transferred As, Se, and Zn, while Trachemys scripta transferred As, Hg, Se, Sr, and Zn. Logarithmic non-linear relationships between hatchling and egg concentrations indicated that turtles partially assimilated elements present in eggs. In systems contaminated with multiple trace elements, our data show that maternal transfer and embryonic assimilation are element- and species-specific, and may be inconsistent even among closely-related species.
Show more [+] Less [-]Fe biogeochemistry in reclaimed acid mine drainage precipitates—Implications for phytoremediation
2014
Rojas, Claudia | Martínez, Carmen Enid | Bruns, Mary Ann
At a 50-year-old coal mine drainage barrens in central Pennsylvania, USA, we evaluated the biogeochemistry of acidic, Fe(III)oxy(hydr)oxide precipitates in reclaimed plots and compared them to untreated precipitates in control areas. Reclaimed plots supported successional vegetation that became established after a one-time compost and lime treatment in 2006, while control plots supported biological crusts. Precipitates were sampled from moist yet unsaturated surface layers in an area with lateral subsurface flow of mine drainage above a fragipan. Fe(II) concentrations were three- to five-fold higher in reclaimed than control precipitates. Organically bound Fe and amorphous iron oxides, as fractions of total Fe, were also higher in reclaimed than control precipitates. Estimates of Fe-reducing and Fe-oxidizing bacteria were four- to tenfold higher in root-adherent than both types of control precipitates. By scaling up measurements from experimental plots, total Fe losses during the 5-yr following reclamation were estimated at 45 t Fe ha−1 yr−1.
Show more [+] Less [-]Distribution, sources and potential toxicological significance of polycyclic aromatic hydrocarbons (PAHs) in surface soils of the Yellow River Delta, China
2014
Yuan, Hongming | Li, Tiegang | Ding, Xigui | Zhao, Guangming | Ye, Siyuan
PAH concentrations of 61 surface soil samples collected from the Yellow River Delta (YRD), China were measured to determine occurrence levels, sources, and potential toxicological significance of PAHs. The total concentrations of ∑PAHs ranged from 27 to 753ng/g d.w., with a mean of 118±132ng/g. The highest concentrations was found in the mid-southern part of the YRD (753ng/g), which was associated with the oil exploration. The ratios indicated that the PAHs throughout the YRD were mostly of pyrogenic origin; while various sites in mid-southern part in the region were derived mainly from the petrogenic sources. Multivariate statistical analyses supported that the PAHs in surface soils of the YRD were principally from the coal and biomass combustion, petroleum spills, and/or vehicular emissions. The toxic assessment suggested that the PAHs in soils were at low potential of ecotoxicological contamination level for the YRD.
Show more [+] Less [-]Levels and neurodevelopmental effects of polycyclic aromatic hydrocarbons in settled house dust of urban dwellings on preschool–aged children in Nanjing, China
2014
Wang, Bing–Ling | Pang, Shu–Tao | Zhang, Xiao–Ling | Li, Xi–Ling | Sun, Yong–Gang | Lu, Xiao–Mei | Zhang, Qi | Zhang, Zheng–Dong
This study investigated levels and possible determinants of polycyclic aromatic hydrocarbons (PAHs) in settled house dust of urban dwellings with preschool–aged children in Nanjing, China. The possible neurodevelopmental effects of house–dust PAHs on the children were also investigated. Settled house dust was collected from 203 urban houses. Fifteen PAHs were measured using an HPLC with a fluorescence detector and wavelength programming. The Child Behavior Checklist and the Gesell Development Inventory were used to evaluate the overall development of the children. PAHs were detected in settled house dust of >90% of houses, where high molecular weight PAHs predominated. Most PAHs with two or three rings were found at significantly higher levels in indoor compared with outdoor dust. PAH isomeric ratios showed that PAHs with four or more rings might be derived from outdoor coal burning sources. Naphthalene was found at lower concentrations in houses with more hours of natural ventilation, while pyrene, chrysene (Chr) and benzo[k]fluoranthene (BkF) were present at higher concentrations in these houses. A higher floor level correlated with lower levels of PAHs, especially those with four or more rings, while older houses had higher PAH levels. Benzo[a]pyrene (BaP) and indeno[1,2,3–cd]pyrene levels were positively associated with most behavioral problem scores. Higher BaP and benzo[g,h,i]perylene levels showed lower Gesell language development quotient (DQs), and higher Chr and BkF were associated with lower Gesell social skill DQs. In conclusion, 15 PAHs are ubiquitous in urban settled house dust, where outdoor coal burning and indoor cooking oil fumes are the two main sources of PAHs in Nanjing, China. Natural ventilation, floor level and residence age potentially influence house dust PAH levels. The potential adverse effect of postnatal exposure to PAHs on the behavior and neurodevelopment of preschool–aged children requires follow up in larger studies.
Show more [+] Less [-]Distribution and transportation of polycyclic aromatic hydrocarbons (PAHs) at the Humen river mouth in the Pearl River delta and their influencing factors
2014
Liu, Feng | Yang, Qingshu | Hu, Yujie | Du, Huanhuan | Yuan, Fei
Five different water samples were collected from the surface to the bottom layers at the Humen river mouth in the Pearl River delta during the flood and ebb tides in August 2011, respectively. Changes in the distribution and characteristics of polycyclic aromatic hydrocarbons (PAHs) were examined to explore their transportation process. More than 62 types of PAHs were detected in the water columns. The mean concentration of the total PAHs ranged from 849.33 to 1370.53ng/l and from 629.21 to 2019.91ng/l during the flood and ebb tides, respectively. Furthermore, 2-ring PAHs were the most abundant species, followed by 3-ring PAHs. There were different composition patterns of the PAHs during the flood and ebb tides. And the transportation process of PAHs was influenced by their sources and different estuarine hydrodynamics. Analysis of the sources of the PAHs indicated that the PAHs were derived from primarily petroleum and coal combustion sources.
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