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Prenatal methylmercury exposure through maternal rice ingestion: Insights from a feasibility pilot in Guizhou Province, China
2013
Rothenberg, Sarah E. | Yu, Xiaodan | Zhang, Yumei
Maternal hair and blood were investigated as biomarkers for prenatal methylmercury (MeHg) exposure among seventeen mothers recruited at parturition in Wanshan, Guizhou Province, China, where rice ingestion was the primary MeHg exposure pathway and atmospheric mercury (Hg) levels were elevated. For all three trimesters (n = 51), hair total Hg (THg) and MeHg concentrations ranged from 0.27 to 4.9 μg/g (median: 0.96 μg/g) and 0.077 to 2.3 μg/g (median: 0.43 μg/g), respectively, while blood THg levels ranged from 1.7 to 11 μg/L (median: 3.0 μg/L, n = 17). Despite adequate hair washing procedures, median %MeHg (of THg) was 37% (range: 14–89%, n = 51), indicating exogenous inorganic Hg(II) contamination or incorporation of elemental Hg (Hgo) into the hair shaft were important. Rice MeHg levels (n = 17) were highly correlated with blood THg (r2 = 0.66) compared to hair MeHg (r2 = 0.31) (when variables were log10-transformed), suggesting blood THg was a more preferable biomarker for prenatal MeHg exposure within this population.
Mostrar más [+] Menos [-]Assessment of polybrominated diphenyl ethers (PBDEs) in serum from the Korean general population
2012
Kim, Jongchul | Kang, Jung-Ho | Park, Hyokeun | Baek, Song-Yee | Kim, Yang-ho | Chang, Yoon Seok
In 2009 and 2010, 720 serum samples were collected from non-occupationally exposed study participants at four Korean locations and monitored for the presence of 27 polybrominated diphenyl ether (PBDE) congeners. The median concentrations of Σ₂₇PBDEs (the sum of 27 congeners) and Σ₃–₇PBDEs (the sum of tri- to hepta-BDE congeners) were 6.04 and 4.97 ng/g lipid, respectively. The most abundant congener detected in serum samples was BDE-153, followed by BDE-47 and BDE-99. The median value of Σ₃–₇PBDEs was similar to the median values observed in Asia and Europe, but much lower than that observed in North America. Some significant differences, based on geographic region and sex, were observed. We also observed a positive increase of BDE-153 with regard to age. In addition, we estimated the daily exposure to PBDEs from previously published reports of PBDE concentrations in food and dust, and determined the individual contributions of a variety of sources.
Mostrar más [+] Menos [-]Associations between standardized school performance tests and mixtures of Pb, Zn, Cd, Ni, Mn, Cu, Cr, Co, and V in community soils of New Orleans
2012
Zahran, Sammy | Mielke, Howard W. | Weiler, Stephan | Hempel, Lynn | Berry, Kenneth J. | Gonzales, Christopher R.
In New Orleans a strong inverse association was previously identified between community soil lead and 4th grade school performance. This study extends the association to zinc, cadmium, nickel, manganese, copper, chromium, cobalt, and vanadium in community soil and their comparative effects on 4th grade school performance. Adjusting for poverty, food security, racial composition, and teacher-student ratios, regression results show that soil metals variously reduce and compress student scores. Soil metals account for 22%–24% while food insecurity accounts for 29%–37% of variation in school performance. The impact on grade point averages were Ni > Co > Mn > Cu ∼Cr ∼ Cd > Zn > Pb, but metals are mixtures in soils. The quantities of soil metal mixtures vary widely across the city with the largest totals in the inner city and smallest totals in the outer city. School grade point averages are lowest where the soil metal mixtures and food insecurity are highest.
Mostrar más [+] Menos [-]A comparison of submicrometer particle dose between Australian and Italian people
2012
Buonanno, G. | Morawska, L. | Stabile, L. | Wang, L. | Giovinco, G.
Alveolar and tracheobronchial-deposited submicrometer particle number and surface area data received by different age groups in Australia are shown. Activity patterns were combined with microenvironmental data through a Monte Carlo method. Particle number distributions for the most significant microenvironments were obtained from our measurement survey data and people activity pattern data from the Australian Human Activity Pattern Survey were used. Daily alveolar particle number (surface area) dose received by all age groups was equal to 3.0 × 10¹⁰ particles (4.5 × 10² mm²), varying slightly between males and females. In contrast to gender, the lifestyle was found to significantly affect the daily dose, with highest depositions characterizing adults. The main contribution was due to indoor microenvironments. Finally a comparison between Italian and Australian people in terms of received particle dose was reported; it shows that different cooking styles can affect dose levels: higher doses were received by Italians, mainly due to their particular cooking activity.
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 [-]Arsenic contamination and potential health risk implications at an abandoned tungsten mine, southern China
2010
Liu, Chuan-ping | Luo, Chun-ling | Gao, Yun | Li, Fang-bai | Lin, Lan-wen | Wu, Chang'an | Li, Xiang-Dong
In an extensive environmental study, field samples, including soil, water, rice, vegetable, fish, human hair and urine, were collected at an abandoned tungsten mine in Shantou City, southern China. Results showed that arsenic (As) concentration in agricultural soils ranged from 3.5 to 935 mg kg−1 with the mean value of 129 mg kg−1. In addition, As concentration reached up to 325 μg L−1 in the groundwater, and the maximum As concentration in local food were 1.09, 2.38 and 0.60 mg kg−1 for brown rice, vegetable and fish samples, respectively, suggesting the local water resource and food have been severely contaminated with As. Health impact monitoring data revealed that As concentrations in hair and urine samples were up to 2.92 mg kg−1 and 164 μg L−1, respectively, indicating a potential health risk among the local residents. Effective measurements should be implemented to protect the local community from the As contamination in the environment. It is the first report on arsenic contamination and potential health risk implications at abandoned Lianhuashan tungsten mine.
Mostrar más [+] Menos [-]Organochlorine pesticide residuals in chickens and eggs at a poultry farm in Beijing, China
2009
Tao, S. | Liu, W.X. | Li, X.Q. | Zhou, D.X. | Li, Xunjing | Yang, Y.F. | Yue, D.P. | Coveney, R.M.
Chicken organs, animal feed, droppings, and ambient air were sampled at a farm in Beijing to determine the concentrations of hexachlorocyclohexane isomers (HCHs) and dichlorodiphenyltrichloroethane and metabolites (DDTs). Mean fresh weight concentrations of HCHs and DDTs were 0.122 ± 0.061 ng/g and 0.051 ± 0.038 ng/g in the muscles. These values are 1-2 orders of magnitude lower than those reported in China in 1980. Contaminated feed was the main source of HCHs and DDTs. Only 12.8% of HCH and 3.3% of DDT of the amount consumed were excreted. Accumulated quantities of HCHs and DDTs increased during growth. However, concentrations of HCHs and DDTs did not increase because of dilution from rapid growth. Based on the observed residual levels in mature chicken and the average diet of residents of China, the contributions from chicken and egg consumption to per capita daily intake of HCHs and DDTs were 487% and 88% of those of fish consumption.
Mostrar más [+] Menos [-]Associations of prenatal exposure to phenols with birth outcomes
2013
Tang, Rong | Chen, Min-jian | Ding, Guo-dong | Chen, Xiao-jiao | Han, Xiu-mei | Zhou, Kun | Chen, Li-Mei | Xia, Yan-kai | Tian, Ying | Wang, Xin-ru
Many phenols are known to mimic or antagonize hormonal activities and may adversely affect fetal growth. A study of 567 pregnant women was conducted to investigate the relationship between prenatal phenol exposure and birth outcomes, including birth weight, length, and gestational age. We measured the concentrations of bisphenol A, benzophenone-3, 4-n-octylphenol and 4-n-nonylphenol in maternal urine and examine their association with birth outcomes. Categories of urinary benzophenone-3 concentration were associated with decreased gestational age in all infants (p for trend = 0.03). Between middle and low exposure groups, we also found bisphenol A was negatively associated with gestational duration (βadjusted = −0.48 week; 95% confidence interval: −0.91, −0.05). After stratification by gender, we found the consistent results in infant boys with those in all infants, but we did not observe significant association for girls. In conclusion, we found prenatal phenol exposure was sex-specifically related to birth outcomes.
Mostrar más [+] Menos [-]Assessing mixed trace elements in groundwater and their health risk of residents living in the Mekong River basin of Cambodia
2013
Phan, Kongkea | Phan, Samrach | Huoy, Laingshun | Suy, Bunseang | Wong, Ming Hung | Jamal Hisham Hashim, | Mohamed Yasin, Mohamed Salleh | Aljunid, Syed Mohamed | Sthiannopkao, Suthipong | Kim, Kyoung-Woong
We investigated the potential contamination of trace elements in shallow Cambodian groundwater. Groundwater and hair samples were collected from three provinces in the Mekong River basin of Cambodia and analyzed by ICP-MS. Groundwater from Kandal (n = 46) and Kraite (n = 12) were enriched in As, Mn, Ba and Fe whereas none of tube wells in Kampong Cham (n = 18) had trace elements higher than Cambodian permissible limits. Risk computations indicated that 98.7% and 12.4% of residents in the study areas of Kandal (n = 297) and Kratie (n = 89) were at risk of non-carcinogenic effects from exposure to multiple elements, yet none were at risk in Kampong Cham (n = 184). Arsenic contributed 99.5%, 60.3% and 84.2% of the aggregate risk in Kandal, Kratie and Kampong Cham, respectively. Sustainable and appropriate treatment technologies must therefore be implemented in order for Cambodian groundwater to be used as potable water.
Mostrar más [+] Menos [-]Inorganic arsenic and trace elements in Ghanaian grain staples
2011
Adomako, Eureka E. | Williams, Paul N. | Deacon, Claire | Meharg, Andrew A.
A total of 549 samples of rice, maize, wheat, sorghum and millet were obtained from markets in Ghana, the EU, US and Asia. Analysis of the samples, originating from 21 countries in 5 continents, helped to establish global mean trace element concentrations in grains; thus placing the Ghanaian data within a global context. Ghanaian rice was generally low in potentially toxic elements, but high in essential nutrient elements. Arsenic concentrations in rice from US (0.22 mg/kg) and Thailand (0.15 mg/kg) were higher than in Ghanaian rice (0.11 mg/kg). Percentage inorganic arsenic content of the latter (83%) was, however, higher than for US (42%) and Thai rice (67%). Total arsenic concentration in Ghanaian maize, sorghum and millet samples (0.01 mg/kg) was an order of magnitude lower than in Ghanaian rice, indicating that a shift from rice-centric to multigrain diets could help reduce health risks posed by dietary exposure to inorganic As.
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