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Distribution of perfluorochemicals between sera and milk from the same mothers and implications for prenatal and postnatal exposures
2011
Kim, Seung-Kyu | Lee, Kyu Tae | Kang, Chang Seong | Tao, Lin | Kannan, Kurunthachalam | Kim, Kyung-Ryul | Kim, Chan-Kook | Lee, Jung Suk | Park, Pan Soo | Yoo, Yung Wook | Ha, Jeong Yi | Shin, Yong-Seung | Lee, Jong Hyeon
The levels of six perfluorocarboxylates (PFCAs), four perfloroalkylsulfonates (PFASs), and one sulfonamide were measured in paired samples of maternal serum, umbilical cord serum, and breast milk. The maternal and cord sera were strongly correlated with each other for all measured compounds (r > 0.5 and p < 0.01). Nevertheless, there was a significant difference in compound composition profile between the two sera matrices, with a more depletion of the longer chain compounds in cord serum. The transfer efficiency values from maternal to cord serum (TFCS/MS) decreased by 70% with each increasing unit of –CF₂ chain within a PFCA group, and for perfluorooctanesulfonate (PFOS), by a half compared to perfluorooctanoate (PFOA). In contrast to the strong correlation in concentrations between the two sera matrices, the pattern of compounds in breast milk differed considerably with those in sera. Accordingly, compound- and matrix-specific transfer must be considered when assessing prenatal and postnatal exposure.
Mostrar más [+] Menos [-]Urban and rural mortality rates during heat waves in Berlin and Brandenburg, Germany
2011
Gabriel, Katharina M.A. | Endlicher, Wilfried R.
In large cities such as Berlin, human mortality rates increase during intense heat waves. Analysis of relevant data from north-eastern Germany revealed that, during the heat waves that occurred between 1990 and 2006, health risks were higher for older people in both rural and urban areas, but that, during the two main heat waves within that 17-year period of time, the highest mortality rates were from the city of Berlin, and in particular from its most densely built-up districts. Adaptation measures will need to be developed, particularly within urban areas, in order to cope with the expected future intensification of heat waves due to global climate change.
Mostrar más [+] Menos [-]Assessing the relationship between global warming and mortality: Lag effects of temperature fluctuations by age and mortality categories
2011
Yu, Weiwei | Mengersen, Kerrie | Hu, Wenbiao | Guo, Yuming | Pan, Xiaochuan | Tong, Shilu
Although interests in assessing the relationship between temperature and mortality have arisen due to climate change, relatively few data are available on lag structure of temperature–mortality relationship, particularly in the Southern Hemisphere. This study identified the lag effects of mean temperature on mortality among age groups and death categories using polynomial distributed lag models in Brisbane, Australia, a subtropical city, 1996–2004. For a 1 °C increase above the threshold, the highest percent increase in mortality on the current day occurred among people over 85 years (7.2% (95% CI: 4.3%, 10.2%)). The effect estimates among cardiovascular deaths were higher than those among all-cause mortality. For a 1 °C decrease below the threshold, the percent increases in mortality at 21 lag days were 3.9% (95% CI: 1.9%, 6.0%) and 3.4% (95% CI: 0.9%, 6.0%) for people aged over 85 years and with cardiovascular diseases, respectively. These findings may have implications for developing intervention strategies to reduce and prevent temperature-related mortality.
Mostrar más [+] Menos [-]In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: A review
2011
Zia, Munir Hussain | Codling, Eton E. | Scheckel, Kirk G. | Chaney, Rufus L.
We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5–10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model).
Mostrar más [+] Menos [-]Screening of pharmaceuticals and hormones at the regional scale, in surface and groundwaters intended to human consumption
2011
Vulliet, Emmanuelle | Cren-Olivé, Cécile
As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed.
Mostrar más [+] Menos [-]Outdoor and indoor cadmium distributions near an abandoned smelting works and their relations to human exposure
2011
Spurgeon, David J. | Lawlor, Alan | Hooper, Helen L. | Wadsworth, Richard | Svendsen, Claus | Thomas, Laura D.K. | Ellis, James K. | Bundy, Jacob G. | Keun, Hector C. | Jarup, Lars
The relationship of measured or modelled Cd concentrations in soil, house dust and available to plants with human urinary Cd concentrations were assessed in a population living around a Cd/Pb/Zn smelter in the UK. Modelled air concentrations explained 35% of soil Cd variation indicating the smelter contributed to soil Cd loads. Multi-variate analysis confirmed a significant role of biological and life-style factors in determining urinary Cd levels. Significant correlations of urinary Cd with soil, house dust and modelled plant available Cd concentrations were not, however, found. Potential reasons for the absence of clear relationships include limited environmental contact in urban populations; the role of undefined factors in determining exposure; and the limited spatial scope of the survey which did not sample from the full pollution gradient. Further, the absence of any significant relationship indicates that environmental measures provide limited advantage over atmospheric model outputs for first stage human exposure assessment.
Mostrar más [+] Menos [-]Antagonism of phenanthrene cytotoxicity for human embryo lung fibroblast cell line HFL-I by green tea polyphenols
2011
Mei, Xin | Wu, Yuan-yuan | Mao, Xiao | Tu, You-Ying
Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene.
Mostrar más [+] Menos [-]Ecological risk assessment of heavy metals in sediment and human health risk assessment of heavy metals in fishes in the middle and lower reaches of the Yangtze River basin
2011
Yi, Yujun | Yang, Zhifeng | Zhang, Shanghong
The concentrations of heavy metals (Cr, Cd, Hg, Cu, Zn, Pb and As) in the water, sediment, and fish were investigated in the middle and lower reaches of the Yangtze River, China. Potential ecological risk analysis of sediment heavy metal concentrations indicated that six sites in the middle reach, half of the sites in the lower reach, and two sites in lakes, posed moderate or considerable ecological risk. Health risk analysis of individual heavy metals in fish tissue indicated safe levels for the general population and for fisherman but, in combination, there was a possible risk in terms of total target hazard quotients. Correlation analysis and PCA found that heavy metals (Hg, Cd, Pb, Cr, Cu, and Zn) may be mainly derived from metal processing, electroplating industries, industrial wastewater, and domestic sewage. Hg may also originate from coal combustion. Significant positive correlations between TN and As were observed.
Mostrar más [+] Menos [-]National survey of the levels of persistent organochlorine pesticides in the breast milk of mothers in China
2011
Zhou, Pingping | Wu, Yongning | Yin, Shian | Li, Jingguang | Zhao, Yunfeng | Zhang, Lei | Chen, Huijing | Liu, Yinping | Yang, Xin | Li, Xiaowei
The occurrence of persistent organochlorine pesticides (OCPs) in breast milk samples collected from mothers from twelve provinces in mainland China was investigated. Dichlorodiphenyltrichloroethanes (DDTs) were the most prevalent agent, followed by HCHs and HCB, whereas levels of chlordane compounds, drins and mirex were lower. The relatively lower DDE/DDT ratio in the Fujian rural area suggested more recent exposure to DDT than in other areas. The mean level of DDTs in breast milk from the southern China was higher than those from northern China (p < 0.05). A positive correlation was observed between concentration of DDTs in human milk and consumption of animal-origin food, suggesting that this parameter could play an important part in influencing OCPs burdens in lactating women. The mean estimated daily intakes of different OCPs for breastfed infants were lower than the tolerable daily intake.
Mostrar más [+] Menos [-]Distribution, availability, and sources of trace metals in different particle size fractions of urban soils in Hong Kong: Implications for assessing the risk to human health
2011
Luo, Xiao-san | Yu, Shen | Li, Xiang-Dong
The concentration and loading distribution of trace metals (Cu, Zn, Pb, Co, Ni, Cr, and Mn) and major elements (Al, Ca, Fe, and Mg) in different particle size fractions (2000–280, 280–100, 100–50, 50–10, 10–2, and <2μm) of surface soils from highly urbanized areas in Hong Kong were studied. The enrichment of Pb, Cu, and Zn in the urban soils was strongly influenced by anthropogenic activities, and Pb accumulated in fine particles was mainly derived from past vehicular emissions as shown by Pb isotopic signatures. Trace metals primarily accumulated in clay, fine silt, and very fine sand fractions, and might pose potential health risks via the inhalation of resuspended soil particles in the air (PM₁₀ or PM₂.₅), and ingestion of adhered soils through the hand-to-mouth pathway. The mobility, bioavailability, and human bioaccessibility of Pb and Zn in bulk soils correlated significantly with metal concentrations in fine silt and/or very fine sand fractions.
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