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Annual Effective Dose Assessment of Radon in Drinking Water from Abandoned Tin and Cassiterite Mining Site in Oyun, Kwara State, Nigeria
2022
Orosun, Muyiwa Michael | Ajibola, Taiye Benjamin | Ehinlafa, Olusegun Emmanuel | Issah, Ahmad Kolawole | Salawu, Banji Naheem | Ishaya, Sunday Danladi | Ochommadu, Kelechi Kingsley | Adewuyi, Abayomi Daniel
Mining activities are generally known to enhance the concentration of primordial radionuclides in the environment thereby contributing immensely to human exposure to ionizing radiation of terrestrial origin. Thus, the abandoned Tin and Cassiterite mining site in Oyun, Kwara State, Nigeria, is believed to cause radiological implications on local residents. Assessment of radon concentration in surface water from the study area was carried out using RAD7-Active Electronic detector big bottle system. In order to ascertain the risk or hazard incurable in consuming such water, 12 samples were analysed and used in the estimation of annual effective dose of radon. The measured maximum and minimum radon concentrations were found to be 44.95 and 21.03 Bq/L with average of 35.86 Bq/L. These values are quite greater than the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) recommended limits of 11.1.Bq/L. The estimated total effective dose (AEDEtotal) was found to be within the range of 206.52 and 441.41 μSvy-1, and an average of 352.20 μSvy-1 for Adults, 283.30 and 605.47 μSvy-1, and average of 483.10 μSvy-1 for Children, and finally, 321.70 and 687.47 μSvy-1 with average of 548.64 μSvy-1 for Infants, respectively. These values were higher than the recommended limit of 100 µSvy-1 and 200 µSvy-1 for adult and children respectively. Furthermore, worries should be noted about the probabilistic cumulative effect on the consumers of such water if the ingestion is for an extended period of time.
Показать больше [+] Меньше [-]Effect of exposures to mixtures of lead and various metals on hypertension, pre-hypertension, and blood pressure: A cross-sectional study from the China National Human Biomonitoring
2022
Qu, Yingli | Lv, Yuebin | Ji, Saisai | Ding, Liang | Zhao, Feng | Zhu, Ying | Zhang, Wenli | Hu, Xiaojian | Lu, Yifu | Li, Yawei | Zhang, Xu | Zhang, Mingyuan | Yang, Yanwei | Li, Chengcheng | Zhang, Miao | Li, Zheng | Chen, Chen | Zheng, Lei | Gu, Heng | Zhu, Huijuan | Sun, Qi | Cai, Jiayi | Song, Shixun | Ying, Bo | Lin, Shaobin | Cao, Zhaojin | Liang, Donghai | Ji, John S. | Ryan, P Barry | Barr, Dana Boyd | Shi, Xiaoming
We aimed to explore the effects of mixtures of lead and various metals on blood pressure (BP) and the odds of pre-hypertension (systolic blood pressure (SBP) 120–139 mmHg, and/or diastolic blood pressure (DBP) 80–89 mmHg) and hypertension (SBP/DBP ≥140/90 mmHg) among Chinese adults in a cross-sectional study. This study included 11,037 adults aged 18 years or older from the 2017–2018 China National Human Biomonitoring. Average BP and 13 metals (lead, antimony, arsenic, cadmium, mercury, thallium, chromium, cobalt, molybdenum, manganese, nickel, selenium, and tin) in blood and urine were measured and lifestyle and demographic data were collected. Weighted multiple linear regressions were used to estimate associations of metals with BP in both single and multiple metal models. Weighted quantile sum (WQS) regression was performed to assess the relationship between metal mixture levels and BP. In the single metal model, after adjusting for potential confounding factors, the blood lead levels in the highest quartile were associated with the greater odds of both pre-hypertension (odds ratio (OR): 1.56, 95% CI: 1.22–1.99) and hypertension (OR:1.75, 95% CI: 1.28–2.40) when compared with the lowest quartile. We also found that blood arsenic levels were associated with increased odds of pre-hypertension (OR:1.31, 95% CI:1.00–1.74), while urinary molybdenum levels were associated with lower odds of hypertension (OR:0.68, 95% CI:0.50–0.93). No significant associations were found for the other 10 metals. WQS regression analysis showed that metal mixture levels in blood were significantly associated with higher SBP (β = 1.56, P < 0.05) and DBP (β = 1.56, P < 0.05), with the largest contributor being lead (49.9% and 66.8%, respectively). The finding suggests that exposure to mixtures of metals as measured in blood were positively associated with BP, and that lead exposure may play a critical role in hypertension development.
Показать больше [+] Меньше [-]Effect of prothioconazole on the degradation of microplastics derived from mulching plastic film: Apparent change and interaction with heavy metals in soil
2020
Li, Ruojia | Liu, Yi | Sheng, Yingfei | Xiang, Qingqing | Zhou, Ying | Cizdziel, James V.
Microplastic pollution is a major global environmental problem in both aquatic and terrestrial environments. Pesticides are frequently applied to agricultural soil to reduce the effects of pests on crops, but may also affect the degradation of plastics. In this study, we generated microplastics from polyethylene (PE) film and biodegradable poly(butylene adipate-co-terephthalate) (PBAT) film and determined (1) the effect of prothioconazole on degradation of the microplastics, and (2) the adsorption and release characteristics of heavy metals (Cr, Cu, As, Pb, Ba, and Sn) by the microplastics during degradation process. Changes of surface functional groups and morphologies were measured by FTIR and SEM, while metal concentrations were determined by ICPMS. Prothioconazole was found to promote plastic degradation. PBAT degraded faster and adsorbed more heavy metals from the soil than PE. Whether the microplastics adsorb or release heavy metals depended on the metal and their concentrations. Prothioconazole inhibited the adsorption of Cr, As, Pb and Ba by microplastics, promoted the adsorption of Cu, and had no significant effect for Sn. These results can help to assess the ecological risk of microplastic pollution from plastic mulch when combined with heavy metals.
Показать больше [+] Меньше [-]Antifouling paint particles in intertidal estuarine sediments from southwest England and their ingestion by the harbour ragworm, Hediste diversicolor
2019
Muller-Karanassos, Christina | Turner, Andrew | Arundel, William | Vance, Tom | Lindeque, Penelope K. | Cole, Matthew
Antifouling paint particles (APPs) of between 500 μm and >2 mm in diameter have been identified in silty, intertidal estuarine sediments through a combination of microscopy and x-ray fluorescence spectrometry. APPs were heterogeneously distributed, with maximal concentrations of 430 particles L−1 (0.2 g L−1) near to a facility where boats are regularly maintained and 400 particles L−1 (4.2 g L−1) at a location where old boats had been abandoned, with the majority of particles encountered in the finest size fraction retrieved. APPs contained variable concentrations of Cu, Zn, Sn and Pb, with respective maxima of 562,000, 269,000, 9,970 and 126,000 mg kg−1. These characteristics are attributed to a multitude of contemporary and historic sources of an assortment of formulations and result in significant but heterogeneous metal contamination of local sediments. APPs were also identified in the guts of the deposit-feeding ragworm, Hediste diversicolor, that inhabited sediments impacted by abandoned boats or boating activities. The tissue of H. diversicolor was particularly enriched in Cu where ingested APPs were observed, with a significant correlation between dry weight Cu concentrations in the two media (r = 0.734) presumably reflecting the inability of the animal to regulate this metal. While the toxicity of APPs requires further investigation, there is clearly a need for stricter regulations on antifouling wastes in boatyards and marinas and a requirement to better manage abandoned boats.
Показать больше [+] Меньше [-]Environmental tin exposure in a nationally representative sample of U.S. adults and children: The National Health and Nutrition Examination Survey 2011–2014
2018
Lehmler, Hans-Joachim | Gadogbe, Manuel | Liu, Buyun | Bao, Wei
Tin is a naturally occurring heavy metal that occurs in the environment in both inorganic and organic forms. Human exposure to tin is almost ubiquitous; however, surprisingly little is known about factors affecting environmental tin exposure in humans. This study analyzed demographic, socioeconomic and lifestyle factors associated with total urinary tin levels in adults (N = 3522) and children (N = 1641) participating in the National Health and Nutrition Examination Survey (NHANES) 2011–2014, a nationally representative health survey in the United States. Urinary tin levels, a commonly used biomarker of environmental tin exposure, were determined by inductively coupled plasma mass spectrometry (ICP-MS). Detection frequencies of tin were 87.05% in adults and 91.29% in children. Median and geometric mean levels of urinary tin in the adult population were 0.42 μg/L and 0.49 μg/L, respectively. For children, median and geometric mean levels of urinary tin were 0.60 μg/L and 0.66 μg/L, respectively. Age was identified as an important factor associated with urinary tin levels. Median tin levels in the ≥60 year age group were almost 2-fold higher than the 20–39 year age group. Tin levels in children were 2-fold higher than in adolescents. Race/ethnicity and household income were associated with tin levels in both adults and children. In addition, physical activity was inversely associated with urinary tin levels in adults. These results demonstrate that total tin exposures vary across different segments of the general U.S. population. Because the present study does not distinguish between organic and inorganic forms of tin, further studies are needed to better characterize modifiable factors associated with exposures to specific tin compounds, with the goal of reducing the overall exposure of the U.S. population.
Показать больше [+] Меньше [-]Presence, mobility and bioavailability of toxic metal(oids) in soil, vegetation and water around a Pb-Sb recycling factory (Barcelona, Spain)
2018
Mykolenko, S. | Liedienov, V. | Kharytonov, M. | Makieieva, N. | Kuliush, T. | Queralt, I. | Marguí, E. | Hidalgo, M. | Pardini, G. | Gispert, M.
The work was conducted to establish contamination from improper disposal of hazardous wastes containing lead (Pb) and antimony (Sb) into nearby soils. Besides other elements in the affected area, the biological role of Sb, its behaviour in the pedosphere and uptake by plants and the food chain was considered. Wastes contained 139532 ± 9601 mg kg−1 (≈14%) Pb and 3645 ± 194 mg kg−1 (≈0.4%) Sb respectively and variability was extremely high at a decimetre scale. Dramatically high concentrations were also found for As, Cd, Cu, Mn, Ni, Sn and Zn. In adjacent natural soils metal(oid)s amounts decreased considerably (Pb 5034 ± 678 mg kg−1, Sb 112 mg kg−1) though largely exceeded the directives for a given soil use. Metal(oid)s potential mobility was assessed by using H2O→KNO3→EDTA sequential extractions, and EDTA extracts showed the highest concentration suggesting stable humus-metal complexes formation. Nevertheless, selected plants showed high absorption potential of the investigated elements. Pb and Sb values for Dittrichia viscosa grown in wastes was 899 ± 627 mg kg−1 and 37 ± 33 mg kg−1 respectively. The same plant showed 154 ± 99 mg kg−1 Pb and 8 ± 4 mg kg−1 Sb in natural soils. Helichrysum stoechas had 323 ± 305 mg kg−1 Pb, and 8 ± 3 mg kg−1 Sb. Vitis vinifera from alongside vineyards contained 129 ± 88 mg kg−1 Pb and 18 ± 9 mg kg−1 Sb, indicating ability for metal uptake and warning on metal diffusion through the food chain. The biological absorption coefficient (BAC) and the translocation factor (TF) assigned phytoextraction potential to Dittrichia viscosa and Foeniculum vulgare and phytostabilization potential to Helichrysum stoechas. Dissolved metal (oid)s in the analysed water strongly exceeded the current directive being a direct threat for livings. Data warned against the high contamination of the affected area in all its compartments. Even though native plants growing in metal-contaminated sites may have phytoremediation potential, high risk of metal diffusion may threat the whole ecosystem.
Показать больше [+] Меньше [-]Indoor air pollution affects hypertension risk in rural women in Northern China by interfering with the uptake of metal elements: A preliminary cross-sectional study
2018
Wang, Bin | Zhu, Yibing | Pang, Yiming | Xie, Jing | Hao, Yongxiu | Yan, Huina | Li, Zhiwen | Ye, Rongwei
Coal combustion and passive smoking are two important contributors to indoor air pollution (IAP) in rural areas of northern China. Although the association between outdoor air pollutants and hypertension risk had been widely reported, fewer studies have examined the relationship between IAP and hypertension risk. This study evaluated the association between IAP and hypertension risk in housewives in rural areas of northern China and the potential mediation pathway of metal elements. Our cross-sectional study, conducted in Shanxi Province, China, enrolled 367 subjects without taking anti-hypertensive drugs, including 142 subjects with hypertension (case group) and 225 subjects without hypertension (control group). We collected information on energy use characteristics and lifestyle using questionnaires. An IAP exposure index was developed to indicate the population exposure to coal combustion and passive smoking. Scalp hair samples were collected from the housewives and various trace and major metal elements were measured. Our results revealed that the IAP index was positively correlated with systolic and diastolic blood pressure. A significant association between the IAP index and hypertension risk was found both without [odds ratio (95% confidence interval, CI) = 2.08 (1.30–3.31)] and with [OR (95% CI) = 2.52 (1.46–4.36)] adjustment for confounders. We also observed that the IAP index was positively correlated with the arsenic, lead, and rare earth element levels in hair samples, and negatively correlated with the levels of some other trace elements (i.e., chromium, cobalt, nickel, and tin) and alkaline earth elements (i.e., calcium, magnesium, and barium) with an overall p value of <0.01. We concluded that IAP may contribute to the development of hypertension in rural housewives in northern China, possibly by interfering with the uptake of metal elements.
Показать больше [+] Меньше [-]From TBT to booster biocides: Levels and impacts of antifouling along coastal areas of Panama
2018
Batista-Andrade, Jahir Antonio | Caldas, Sergiane Souza | Batista, Rodrigo Moço | Castro, Italo Braga | Fillmann, Gilberto | Primel, Ednei Gilberto
Antifouling biocides in surface sediments and gastropod tissues were assessed for the first time along coastal areas of Panama under the influence of maritime activities, including one of the world's busiest shipping zones: the Panama Canal. Imposex incidence was also evaluated in five muricid species distributed along six coastal areas of Panama. This TBT-related biological alteration was detected in three species, including the first report in Purpura panama. Levels of organotins (TBT, DBT, and MBT) in gastropod tissues and surficial sediments ranged from <5 to 104 ng Sn g⁻¹ and <1–149 ng Sn g⁻¹, respectively. In addition, fresh TBT inputs were observed in areas considered as moderate to highly contaminated mainly by inputs from fishing and leisure boats. Regarding booster biocides, TCMTB and dichlofluanid were not detected in any sample, while irgarol 1051, diuron and DCOIT levels ranged from <0.08 to 2.8 ng g⁻¹, <0.75–14.1 ng g⁻¹, and <0.38–81.6 ng g⁻¹, respectively. The highest level of TBT (149 ng Sn g⁻¹) and irgarol 1051 (2.8 ng g⁻¹), as well as relevant level of DCOIT (5.7 ng g⁻¹), were detected in a marina used by recreational boats. Additionally, relatively high diuron values (14.1 ng g⁻¹) were also detected in the Panama Canal associate to a commercial port. DCOIT concentrations were associated with the presence of antifouling paint particles in sediments obtained nearby shipyard or boat maintenance sites. The highest levels of TBT, irgarol 1051, and diuron exceeded international sediment quality guidelines indicating that toxic effects could be expected in coastal areas of Panama. Thus, the simultaneous impacts produced by new and old generations of antifouling paints highlight a serious environmental issue in Panamanian coastal areas.
Показать больше [+] Меньше [-]Photochemical reactions between mercury (Hg) and dissolved organic matter decrease Hg bioavailability and methylation
2017
Luo, Hong-Wei | Yin, Xiangping | Jubb, Aaron M. | Chen, Hongmei | Lu, Xia | Zhang, Weihua | Lin, Hui | Yu, Han-Qing | Liang, Liyuan | Sheng, Guo-Ping | Gu, Baohua
Atmospheric deposition of mercury (Hg) to surface water is one of the dominant sources of Hg in aquatic environments and ultimately drives methylmercury (MeHg) toxin accumulation in fish. It is known that freshly deposited Hg is more readily methylated by microorganisms than aged or preexisting Hg; however the underlying mechanism of this process is unclear. We report that Hg bioavailability is decreased by photochemical reactions between Hg and dissolved organic matter (DOM) in water. Photo-irradiation of Hg-DOM complexes results in loss of Sn(II)-reducible (i.e. reactive) Hg and up to an 80% decrease in MeHg production by the methylating bacterium Geobacter sulfurreducens PCA. Loss of reactive Hg proceeded at a faster rate with a decrease in the Hg to DOM ratio and is attributed to the possible formation of mercury sulfide (HgS). These results suggest a new pathway of abiotic photochemical formation of HgS in surface water and provide a mechanism whereby freshly deposited Hg is readily methylated but, over time, progressively becomes less available for microbial uptake and methylation.
Показать больше [+] Меньше [-]Relationships between seminal plasma metals/metalloids and semen quality, sperm apoptosis and DNA integrity
2017
Wang, Yi-Xin | Wang, Peng | Feng, Wei | Liu, Chong | Yang, Pan | Chen, Ying-Jun | Sun, Li | Sun, Yang | Yue, Jing | Gu, Long-Jie | Zeng, Qiang | Lu, Wen-Qing
This study aimed to investigate the relationships between environmental exposure to metals/metalloids and semen quality, sperm apoptosis and DNA integrity using the metal/metalloids levels in seminal plasma as biomarkers. We determined 18 metals/metalloids in seminal plasma using an inductively coupled plasma-mass spectrometry among 746 men recruited from a reproductive medicine center. Associations of these metals/metalloids with semen quality (n = 746), sperm apoptosis (n = 331) and DNA integrity (n = 404) were evaluated using multivariate linear and logistic regression models. After accounting for multiple comparisons and confounders, seminal plasma arsenic (As) quartiles were negatively associated with progressive and total sperm motility using multivariable linear regression analysis, which were in accordance with the trends for increased odds ratios (ORs) for below-reference semen quality parameters in the logistic models. We also found inverse correlations between cadmium (Cd) quartiles and progressive and total sperm motility, whereas positive correlations between zinc (Zn) quartiles and sperm concentration, between copper (Cu) and As quartiles and the percentage of tail DNA, between As and selenium (Se) quartiles and tail extent and tail distributed moment, and between tin (Sn) categories and the percentage of necrotic spermatozoa (all Ptrend<0.05). These relationships remained after the simultaneous consideration of various elements. Our results indicate that environmental exposure to As, Cd, Cu, Se and Sn may impair male reproductive health, whereas Zn may be beneficial to sperm concentration.
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