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Toxic metals in children's toys and jewelry: Coupling bioaccessibility with risk assessment
2015
Cui, Xin-Yi | Li, Shi-Wei | Zhang, Shu-Jun | Fan, Ying-Ying | Ma, Lena Q.
A total of 45 children's toys and jewelry were tested for total and bioaccessible metal concentrations. Total As, Cd, Sb, Cr, Ni, and Pb concentrations were 0.22–19, 0.01–139, 0.1–189, 0.06–846, 0.14–2894 and 0.08–860,000 mg kg−1. Metallic products had the highest concentrations, with 3–7 out of 13 samples exceeding the European Union safety limit for Cd, Pb, Cr, or Ni. However, assessment based on hazard index >1 and bioaccessible metal showed different trends. Under saliva mobilization or gastric ingestion, 11 out of 45 samples showed HI >1 for As, Cd, Sb, Cr, or Ni. Pb with the highest total concentration showed HI <1 for all samples while Ni showed the most hazard with HI up to 113. Our data suggest the importance of using bioaccessibility to evaluate health hazard of metals in children's toys and jewelry, and besides Pb and Cd, As, Ni, Cr, and Sb in children's products also deserve attention.
Show more [+] Less [-]Carcinogenic risk of chromium, copper and arsenic in CCA-treated wood
2015
Ohgami, Nobutaka | Yamanoshita, Osamu | Thang, Nguyen Dinh | Yajima, Ichiro | Nakano, Chihiro | Wenting, Wu | Ohnuma, Shoko | Kato, Masashi
We showed that 2.1% of 233 pieces of lumber debris after the Great East Japan Earthquake was chromated copper arsenate (CCA)-treated wood. Since hexavalent chromium (Cr), copper (Cu) and pentavalent arsenic (As) in the debris may be diffused in the air via incineration, we exposed human lung normal (BEAS-2B) and carcinoma (A549) cells to Cr, Cu and As at the molar ratio in a representative CCA-treated wood. Co-exposure to 0.10 μM Cr and 0.06 μM As, which solely had no effect on colony formation, synergistically promoted colony formation in BEAS-2B cells, but not A549 cells, with activation of the PI3K/AKT pathway. Sole exposure and co-exposure to Cu showed limited effects. Since previous reports showed Cr and As concentrations to which human lungs might be exposed, our results suggest the importance to avoid diffusion of Cr and As in the air via incineration of debris including CCA-treated wood after the disaster.
Show more [+] Less [-]Increase in polycyclic aromatic hydrocarbon (PAH) emissions due to briquetting: A challenge to the coal briquetting policy
2015
Chen, Yingjun | Zhi, Guorui | Feng, Yanli | Chongguo Tian, | Bi, Xinhui | Li, Jun | Zhang, Gan
Both China and UNEP recommend replacing raw coal chunks with coal briquettes in household sector as clean coal technology (CCT), which has been confirmed by the decreased emissions of particulate matter and black carbon. However, the clean effect has never been systematically checked by other pollutants like polycyclic aromatic hydrocarbons (PAHs). In this study, 5 coals with different geological maturities were processed as both chunks and briquettes and burned in 3 typical coal stoves for the measurement of emission factors (EFs) of particle-bound PAHs. It was found that the EFs of 16 parent PAHs, 26 nitrated PAHs, 6 oxygenated PAHs, and 8 alkylated PAHs for coal briquettes were 6.90 ± 7.89, 0.04 ± 0.03, 0.65 ± 0.40, and 72.78 ± 18.23 mg/kg, respectively, which were approximately 3.1, 3.7, 1.9, and 171 times those for coal chunks, respectively. Such significant increases in PAH emissions increased human health risk and challenged the policy of CCT.
Show more [+] Less [-]Evaluating the efficacy of playground washing to reduce environmental metal exposures
2015
Taylor, Mark Patrick | Zahran, Sammy | Kristensen, Louise | Rouillon, Marek
Washing and wet mopping is often advocated as a remedial treatment to limit exposure to lead dust. Here, surface and pre- and post-play wipes were measured to ascertain dust metal exposures (arsenic, cadmium, copper, lead and zinc) following play routines at four playgrounds in the smelter city of Port Pirie, South Australia, which are washed regularly. Although post-play hand wipe metals were 55.9% (95% CI: −0.78, −0.34) lower on wash days, loadings increased ∼5.1% (95% CI: 1.2, 11.7) per hour after washing. Despite washing, post-play hand lead exceeded a conservative value of 800 μg/m2 within 24 h or sooner, with loadings increasing in proximity to the smelter. Post-play lead loadings were always >1000 μg/m2 at the playground closest to smelter. Playground washing results in short-lived exposure reduction and effective treatment requires elimination of smelter emissions.
Show more [+] Less [-]Endosulfan, pentachlorobenzene and short-chain chlorinated paraffins in background soils from Western Europe
2015
(Kevin C.),
Soils are major reservoirs for many persistent organic pollutants (POPs). In this study, “newly” regulated POPs i.e. Σendosulfans (α-endosulfan, β-endosulfan, endosulfan sulfate), pentachlorobenzene (PeCB), and short-chain chlorinated paraffins (SCCPs) were determined in background samples from woodland (WL) and grassland (GL) surface soil, collected along an existing latitudinal UK–Norway transect. Statistical analysis, complemented with plots showing the predicted equilibrium distribution and mobility potential, was then explored to discuss factors controlling their spatial distribution. SCCPs were detected with the highest average concentrations (35 ± 100 ng/g soil organic matter (SOM)), followed by Σendosulfans (3 ± 3 ng/g SOM) and PeCB (1 ± 1 ng/g SOM). PeCB and Σendosulfans share many similarities in their distribution in these background soils as well as with several legacy POPs. A steep decline in concentrations of SCCPs with increasing latitude indicates that their occurrence is dictated by proximity to source regions, while concentrations of Σendosulfans peaked in regions experiencing elevated precipitation rates.
Show more [+] Less [-]Lead in Chinese villager house dust: Geographical variation and influencing factors
2015
Bi, Xiangyang | Liu, Jinling | Han, Zhixuan | Yang, Wenlin
House dust has been recognized as an important contributor to Pb exposure of children. Here we conducted a comprehensive study to investigate geographical variation of Pb in Chinese villager house dust. The influences of outdoor soil Pb concentrations, dates of construction, house decoration materials, heating types, and site specific pollution on Pb concentrations in house dust were evaluated. The concentrations of Pb in 477 house dust samples collected from twenty eight areas throughout China varied from 12 to 2510 mg/kg, with a median concentration of 42 mg/kg. The median Pb concentrations in different geographical areas ranged from 16 (Zhangjiakou, Hebei) to 195 mg/kg (Loudi, Hunan). No correlations were found between the house dust Pb concentrations and the age of houses, as well as house decoration materials. Whereas outdoor soil, coal combustion, and site specific pollution may be potential Pb sources. Principal component analysis (PCA) confirmed that elemental compositions of the house dust were controlled by both anthropogenic and geogenic sources. Using scanning electron microscopy (SEM), the Pb bearing particles in the house dust were also studied.
Show more [+] Less [-]Effect of iron plaque on antimony uptake by rice (Oryza sativa L.)
2015
Cui, Xiao-Dan | Wang, Yurun | Hockmann, Kerstin | Zhou, Dong-Mei
Although iron (Fe) plaque has been shown to significantly affect the uptake of toxic antimony (Sb) by rice, knowledge about the influence of iron plaque on antimony (Sb) (amount, mechanisms, etc) is, however, limited. Here, the effect of Fe plaque on Sb(III) and Sb(V) (nominal oxidation states) uptake by rice (Oryza sativa L.) was investigated using hydroponic experiments and synchrotron-based techniques. The results showed that iron plaque immobilized Sb on the surface of rice roots. Although the binding capacity of iron plaque for Sb(III) was markedly greater than that for Sb(V), significantly more Sb(III) was taken up by roots and transported to shoots. In the presence of Fe plaque, Sb uptake into rice roots was significantly reduced, especially for Sb(III). However, this did not translate into decreasing Sb concentrations in rice shoots and even increased shoot Sb concentrations during high Fe–Sb(III) treatment.
Show more [+] Less [-]Whole-tree seasonal nitrogen uptake and partitioning in adult Fagus sylvatica L. and Picea abies L. [Karst.] trees exposed to elevated ground-level ozone
2015
Weigt, R.B. | Häberle, K.H. | Rötzer, T. | Matyssek, R.
The effect of long-term exposure of twice-ambient O3 (2 × O3) on whole-tree nitrogen (N) uptake and partitioning of adult beech and spruce was studied in a mixed forest stand, SE-Germany. N uptake as 15N tracer and N pools were calculated using N concentrations and biomass of tree compartments. Whole-tree N uptake tended to be lower under 2 × O3 in both species compared to trees under ambient O3 (1 × O3). Internal partitioning in beech showed significantly higher allocation of new N to roots, with mycorrhizal root tips and fine roots together receiving about 17% of new N (2 × O3) versus 7% (1 × O3). Conversely, in spruce, N allocation to roots was decreased under 2 × O3. These contrasting effects on belowground N partitioning and pool sizes, being largely consistent with the pattern of N concentrations, suggest enhanced N demand and consumption of stored N with higher relevance for tree-internal N cycling in beech than in spruce.
Show more [+] Less [-]Lake retention of manufactured nanoparticles
2015
Koelmans, A.A. | Quik, J.T.K. | Velzeboer, I.
For twenty-five world lakes and three engineered nanoparticles (ENP), lake retention was calculated using a uniformly mixed lake mass balance model. This follows similar approaches traditionally used in water quality management. Lakes were selected such that lake residence times, depths and areal hydraulic loadings covered the widest possible range among existing lakes. Sedimentation accounted for natural colloid as well as suspended solid settling regimes. An ENP-specific mixed sedimentation regime is proposed. This regime combines ENP sedimentation through slow settling with natural colloids from the water column, with faster settling with suspended solids from a selected part of the water column. Although sedimentation data and hydrodynamic concepts as such were not new, their first time combination for application to ENPs shows in which cases lake retention is important for these particles. In combination with ENP emission data, lake retention translates directly into potential risks of ENPs for lake benthic communities.
Show more [+] Less [-]Embryonic eggshell thickness erosion: A literature survey re-assessing embryo-induced eggshell thinning in birds
2015
Orłowski, Grzegorz | Hałupka, Lucyna
Although eggshell thinning has been described mainly in the context of environmental pollution, it can also be the effect of reproductive changes induced by a developing embryo. On the basis of a literature survey of 25 bird species (26 published papers) we reviewed data on embryo-induced eggshell thinning (EET) in three groups of birds: precocials, semi-precocials and altricials. The average EET at the equator of the eggs was 6.4% (median = 4.7%). Our review did not confirm a general prediction of elevated EET at the egg equator in precocial species: altricial birds exhibited the highest EET (average = 12.0%), followed by precocials (7.6%) and semi-precocials (4.2%). We make certain critical recommendations based on the results of this study. Studies aiming to assess variation in eggshell thickness should examine intrinsic factors affecting shell properties of avian eggs, like thickness, which are the result of anatomical or reproductive changes.
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