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Can stable elements (Cs and Sr) be used as proxies for the estimation of radionuclide soil-plant transfer factors?
2022
Guillén, J. | Beresford, N.A. | Baigazinov, Zh | Salas, A. | Kunduzbaeva, A.
Transfer parameters are key inputs for modeling radionuclide transfer in the environment and estimating risk to humans and wildlife. However, there are no data for many radionuclide-foodstuff/wildlife species combinations. The use of parameters derived from stable element data when data for radionuclides are lacking is increasingly common. But, do radionuclides and stable elements behave in a sufficiently similar way in the environment? To answer this question, at least for soil to plant transfer, sampling was conducted in four different countries (England, Kazakhstan, Spain and Ukraine) affected by different anthropogenic radionuclide source terms (in chronological order: global fallout, Semipalatinsk Test Site, the 1957 Windscale accident and the 1986 Chernobyl accident) together with a bibliographical review. Soil to grass transfer parameters (ratio between dry matter concentrations in plant and soil), Fᵥ, for ¹³⁷Cs and ⁹⁰Sr were significantly higher than those for stable elements, suggesting that the use of the latter could lead to underestimating radionuclide concentrations in plant samples Transfer parameters for ¹³⁷Cs and stable Cs were linearly correlated, with a slope of 1.54. No such correlation was observed for ⁹⁰Sr and stable Sr, the mean value of the ⁹⁰Sr:Sr ratio was 35 ranging (0.33–126); few data were available for the Sr comparison. The use of radionuclide transfer parameters, whenever possible, is recommended over derivation from stable element concentrations. However, we acknowledge that for many radionuclides there will be few or no radionuclide data from environmental studies. From analyses of the data collated there is evidence of a decreasing trend in the Fᵥ(¹³⁷Cs)/Fᵥ(Cs) ratio with time from the Chernobyl accident.
Show more [+] Less [-]Associations of plasma metal levels with type 2 diabetes and the mediating effects of microRNAs
2022
Nie, Hongli | Hu, Hua | Li, Zhaoyang | Wang, Ruixin | He, Jia | Li, Peiwen | Li, Weiya | Cheng, Xu | An, Jun | Zhang, Zefang | Bi, Jiao | Yao, Jinqiu | Kwok, Woon | Zhang, Xiaomin | He, Meian
The present study aims to determine the associations of multiple plasma metal levels and plasma microRNAs (miRNAs) with diabetes risk, and further explore the mediating effects of plasma miRNAs on the associations of plasma metal with diabetes risk. We detected plasma levels of 23 metals by inductively coupled plasma mass spectrometry (ICP-MS) among 94 newly diagnosed and untreated diabetic cases and 94 healthy controls. The plasma miRNAs were examined by microRNA Array screening and Taqman real-time PCR validation among the same study population. The multivariate logistic regression models were employed to explore the associations of plasma metal and miRNAs levels with diabetes risk. Generalized linear regression models were utilized to investigate the relationships between plasma metal and plasma miRNAs, and mediation analysis was used to assess the mediating effects of plasma miRNAs on the relationships between plasma metals and diabetes risk. Plasma aluminum (Al), titanium (Ti), copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), strontium (Sr), barium (Ba), and Thallium (Tl) levels were correlated with elevated diabetic risk while molybdenum (Mo) with decreased diabetic risk (P < 0.05 after FDR multiple correction). MiR-122–5p and miR-3141 were positively associated with diabetes risk (all P < 0.05). Ti, Cu, and Zn were positively correlated with miR-122–5p (P = 0.001, 0.028 and 0.004 respectively). Ti, Cu, and Se were positively correlated with miR-3141 (P = 0.003, 0.015, and 0.031 respectively). In addition, Zn was positively correlated with miR-193b-3p (P = 0.002). Ti was negatively correlated with miR-26b-3p (P = 0.016), while Mo and miR-26b-3p were positively correlated (P = 0.042). In the mediation analysis, miR-122–5p mediated 48.0% of the association between Ti and diabetes risk. The biological mechanisms of the association are needed to be explored in further studies.
Show more [+] Less [-]Association between environmental toxic metals, arsenic and polycyclic aromatic hydrocarbons and chronic obstructive pulmonary disease in the US adult population
2022
Rahman, Humairat H. | Niemann, Danielle | Munson-McGee, Stuart H.
Associations between environmental metals and chemicals and adverse human health effects have emerged recently, but the links among environmental metals and respiratory diseases are less studied. The aim of this study was to assess 14 urinary metals (cadmium, barium, cobalt, molybdenum, mercury, cesium, manganese, antimony, lead, tin, strontium, tungsten, thallium, and uranium), seven species of arsenic (arsenous acid, arsenic acid, arsenobetaine, arsenocholine, dimethylarsinic acid, monomethylarsonic acid, and total arsenic) and seven polycyclic aromatic hydrocarbon (PAH) (1-hydroxynaphthalene, 2-hydroxynaphthalene, 3-hydroxyfluorene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 1-hydroxypyrene, 2 & 3-hydroxyphenanthrene) compounds’ concentrations in urine and the correlation with chronic obstructive pulmonary disease (COPD) in the adult US population. A cross-sectional analysis using the 2013–2014 and 2015–2016 National Health and Nutrition Examination Survey (NHANES) dataset was conducted. Self-questionnaires related to COPD criteria were used to identify the COPD cases. The correlation between urinary metals and PAH compounds and COPD was calculated. The total study population analyzed included 2885 adults aged 20 years and older. Seven types of urinary PAHs including 1-hydroxynaphthalene [odds ratio (OR): 1.832, 95% confidence interval (CI): 1.210, 2.775], 2-hydroxynaphthalene [OR: 3.361, 95% CI: 1.519, 7.440], 3-hydroxyfluorene [OR: 2.641, 95% CI: 1.381, 5.053], 2-hydroxyfluorene [OR: 3.628, 95% CI: 1.754, 7.506], 1-hydroxyphenanthrene [OR: 2.864, 95% CI: 1.307, 6.277], 1-hydroxypyrene [OR: 4.949, 95% CI: 2.540, 9.643] and 2 & 3-hydroxyphenanthrene [OR: 3.487, 95% CI: 1.382, 8.795] were positively associated with COPD. Urinary cadmium [OR: 12.382, 95% CI: 4.459, 34.383] and tin [OR: 1.743, 95% CI: 1.189, 2.555] showed positive associations with increased odds of COPD. The other types of urinary metals were not associated with COPD. The study observed that urinary PAHs, cadmium, and tin are significantly associated with COPD.
Show more [+] Less [-]Effect of strontium on nutrient uptake, physiological parameters, and strontium localization in lettuce
2022
Yan, Dong | Ding, Kuke | He, Yingxue | Fan, Li | Che, Yongfei | Zhao, Yingjun | Jiang, Xiaoyan
Human activities increase the risk of stable and radioactive strontium (Sr) isotopes entering the environment and food chain. In this study, the effects of Sr on the nutrient uptake and physiological responses of lettuce under different “Sr treatment” concentrations (0, control, 1, 2, 3, 4, and 5 mM) and “times” (7, 14, and 21 day) were studied in a hydroponic system. In addition, the distribution of Sr on the surfaces and cross-sections of lettuce leaves was revealed by scanning electron microscopy with energy-dispersive X-ray (SEM–EDX) analysis. A two-way analysis of variance (ANOVA) method was used to analyze the significance of “Sr treatment,” “time,” and their “interaction.” The results showed that an increase in Sr uptake in lettuce could significantly reduce the uptake of calcium (Ca). The contents of sulfur (S), potassium (K), and iron (Fe) in lettuce leaves showed significant differences with the sampling day. Similarly, the fresh weight of lettuce leaves and roots as well as the photosynthetic pigment contents of lettuce leaves was also significantly different with the sampling day. The activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) showed significant differences with the sampling day. The activities of SOD and CAT decreased significantly with the sampling day, while POD increased significantly. The MDA content increased significantly with increasing hydroponic Sr concentration on the 21st day. SEM–EDX analysis showed that the weight percentage of Sr in the vascular bundle sheath in the cross-section of lettuce leaves was relatively higher than that in the mesophyll. This study aids our understanding of the distribution of Sr in lettuce leaf tissues and the effect of Sr on lettuce physiology.
Show more [+] Less [-]Hydraulic fracturing flowback chemical composition diversity as a factor determining possibilities of its management
2022
Fajfer, Joanna | Lipińska, Olga | Konieczyńska, Monika
The chemical characteristic of flowback fluid from hydraulic fracturing for shale gas exploration/production in various localizations is presented. The results of statistical analysis have shown that variability in the chemical composition of these fluids is statistically significant and depends on the time difference between fracturing process and flowback sampling as well as sampling spot within the installation for flowback collection. Parameters which depend on sampling schedule (time and spot of sampling) are as follows: electrical conductivity and concentration of ammonia, boron, barium, calcium, lithium, sodium, magnesium, manganese, sodium, strontium, silicate, bromide, and chloride. Independent parameters are pH, total organic carbon (TOC), concentration of potassium, and iron. The ranges of the values of the characteristic parameters were determined, taking into account the representativeness of the samples, supported by statistical tests. The methods for the reuse of flowback fluids in terms of chemical composition are presented.
Show more [+] Less [-]Multi-isotopes revealing the coastal river anthropogenic pollutants and natural material flux to ocean: Sr, C, N, S, and O isotope study
2022
Zhang, Shitong | Han, Guilin | Zeng, Jie | Liu, Man | Li, Xiaoqiang | Liu, Jinke
Coastal river exports massive terrestrial materials to the adjacent marine environment with information about chemical weathering, providing critical insights on riverine flux and the potential impact on marine ecosystem. In this study, the preliminary data of dissolved strontium (Sr) and ⁸⁷Sr/⁸⁶Sr in a typical coastal river in southeastern China were collected along with hydrochemistry and C, N, S, and O isotopes to discriminate the source of terrestrial weathering and the riverine flux. Sr concentrations exhibited a range of 0.084 ~ 1.307 μmol L⁻¹, and ⁸⁷Sr/⁸⁶Sr values ranged 0.7089 ~ 0.7164. The total cationic charge (TZ⁺) ranged 0.2 ~ 11.7 meq L⁻¹ with the predominant Ca²⁺ which accounted for > 50% of TZ⁺, while the anions were dominated by HCO₃⁻. The extremely high Na⁺ and Cl⁻ near the estuary indicated seawater mixing in such a coastal river. δ¹³C-DIC, δ¹⁵N-NO₃⁻, δ¹⁸O-NO₃⁻, and δ³⁴S-SO₄²⁻ of river water ranged − 24.1‰ ~ − 9.2‰, 0.3‰ ~ 22.7‰, − 2.1‰ ~ 21.4‰, and − 9.3‰ ~ 18.0‰, respectively. δ¹³C enhanced correspondingly to decreased δ³⁴S, confirming the attendance of H₂SO₄ in carbonate weathering. Most δ¹⁸O values exhibited within ± 10‰, indicating the dominant nitrification process. δ¹⁵N presented slightly negative relationship with δ¹³C and no obvious correlation with δ³⁴S, indicating relatively limited impact of denitrification. The depleted δ¹³C and δ¹⁵N may be attributed to carbonate dissolution with nitric acids and the oxidation of organic matters into C and N pools. Quantitative analysis revealed that silicate weathering accounts for 79% of total dissolved Sr, indicating the dominant weathering process. The estimated monthly flux of dissolved Sr to the East China Sea was 138.1 tons, demonstrating an potential impact on seawater Sr isotope evolution. Overall, the investigations of multi-isotopes revealed the enhancement of weathering rates and the consequently depleted CO₂ consumption, which further proved the involvement of strong acids (H₂SO₄ and HNO₃). This study provides scientific insight in terrestrial weathering and anthropogenic impact of a typical coastal watershed and may orient the management of environmental issues related to coastal ecosystems.
Show more [+] Less [-]Exposure to mixture of heavy metals and muscle strength in children and adolescents: a population-based study
2022
Wu, Mingyang | Shu, Yanling | Wang, Youjie
Human beings are exposed to heavy metals through various ways in daily life. However, the effect of heavy metal mixtures on muscle strength in children and adolescents remains unclear. We aimed to investigate the relationship of exposure to heavy metal mixtures (barium, cadmium, cobalt, manganese, molybdenum, lead, antimony, strontium, tin, thallium, tungsten, uranium, and cesium) with muscle strength in children and adolescents. A total of 1357 (boys, 50.8%) participants aged between 8 and 17 were extracted from the National Health and Nutrition Examination Surveys 2011–2014. Urine metals were measured by inductively coupled plasma-mass spectrometry. Muscle strength was measured through a grip test using a handgrip dynamometer. Weighted quantile sum regression was performed to estimate the mixture effect of urinary metals on muscle strength. After adjusting for potential confounders, comparing participants in the highest versus lowest quartiles of cobalt, molybdenum, lead, antimony, strontium, thallium, and cesium, the handgrip strength decreased by − 4.48 kg (95% CI: − 6.93, − 2.03), − 6.13 kg (− 8.76, − 3.51), − 2.26 kg (− 4.22, − 0.30), − 2.38 kg (− 4.68, − 0.08), − 2.29 kg (− 4.45, − 0.13), − 4.78 kg (− 7.13, − 2.44), and − 5.68 kg (− 9.20, − 2.17), respectively. Furthermore, exposure to a mixture of metals were also significantly associated with decreased muscle strength (β: − 2.62 kg; 95% CI: − 3.71, − 1.54). Findings from the present study suggest that higher heavy metal exposure and the exposure levels of a mixture of metals in urine are inversely related to handgrip strength, implying that children’s grip strength is not entirely explained by energy intake or lack of exercise, but may be related to environmental pollutants.
Show more [+] Less [-]Immobilization of strontium in geopolymers activated by different concentrations of sodium silicate solutions
2022
Tian, Quanzhi | Pan, Yinhai | Bai, Yingchu | Sasaki, Keiko
Sodium silicate is always used as an activator for the synthesis of geopolymer. However, the effect of sodium silicate concentration on the geopolymer used as adsorbent was still unclear. Therefore, the immobilization of Sr²⁺ in geopolymers activated by different concentrations of sodium silicate was studied through kinetic and isotherm modeling and solid characterizations including XRD, FTIR, TG, SEM–EDS, and N₂ adsorption–desorption isotherm. The adsorption amount of Sr²⁺ decreased with the sequence of S1, S2, and S3. According to the kinetic and isotherm modeling results, these sorption processes fitted better with pseudo-second-order, mainly governed by film diffusion. However, the diffusion mode was gradually closed to particle diffusion as for the sequence of S3, S2, and S1. Besides, the Langmuir model can be more befitting to sorption data than the Freundlich model, and the free energies decreased with the order of S1, S2, and S3. In addition, the specific surface areas did not change regularly with S1, S2, and S3. Thus, the distribution of Al tetrahedrons has a decisive role in the sorption process of Sr²⁺, even though the specific surface area is also a critical factor. More Al tetrahedrons can be formed under the activation of sodium silicate with higher concentration, leading to the low Si/Al molar ratio of the as-synthesized geopolymer.
Show more [+] Less [-]Biological monitoring and health assessment of 21 metal(loid)s in children and adolescents in Liuzhou City, Southwest China
2022
Exposure to metal(loid)s is associated with adverse effects on human health, especially for children and adolescents. This study was designed to evaluate metal(loid)s exposure in 2050 children and adolescents aged 6–18 years from Liuzhou City, Southwest China. The detection rates of 21 elements were all above 99%. We found that age was an important predictor for most elements, and that children exhibited more exposure than adolescents, expect for strontium (p < 0.05). Interestingly, urinary levels were higher in girls for 13 of our study elements. Multiple regression models also showed that dietary habits also affected the distribution of elements. Moreover, we estimated exposure risk by generating the hazard quotient (HQ) for single metal and the hazard index (HI) for the co-occurrence of metals. The HQ of cadmium was > 1 at the P95 value and that the risk of the mixed effect of cadmium, mercury, and thallium was not negligible, and indicated that the associated risk was of concern. Our results provide basic data on the reference values of urinary metal(loid) levels and an assessment of health risks for children and adolescents that reside in industrial areas.
Show more [+] Less [-]Urinary metals, arsenic, and polycyclic aromatic hydrocarbon exposure and risk of chronic bronchitis in the US adult population
2022
Rahman, Humairat H | Niemann, Danielle | Munson-McGee, Stuart H.
Metals, arsenic, and polycyclic aromatic hydrocarbons (PAHs) have all been linked to respiratory diseases. Chronic bronchitis, which is a form of chronic obstructive pulmonary disease (COPD), is a major public health concern and source of morbidity and mortality in the US. The purpose of this study was to analyze the correlation of 14 urinary metals (antimony, barium, cadmium, cesium, cobalt, lead, manganese, mercury, molybdenum, strontium, thallium, tin, tungsten, uranium), seven species of arsenic, and seven forms of polycyclic aromatic hydrocarbon (PAH) concentrations and chronic bronchitis in the US population. A cross-sectional analysis using three datasets from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2016 in adults, aged 20 years and older. Chronic bronchitis was determined using a self-questionnaire from the NHANES dataset. A specialized weighted complex survey design analysis package was used to analyze NHANES data. Multivariate logistic regression models were used to determine the correlation between urinary metals, arsenic, PAHs, and chronic bronchitis. Models were adjusted for lifestyle and demographic factors. A total of 4186 participants were analyzed; 49.8% were female and 40.5% were non-Hispanic White. All seven types of PAHs showed a positive association with chronic bronchitis (1-hydroxynaphthalene odds ratio (OR): 1.559, 95% confidence interval (CI): 1.271–1.912; 2-hydroxynaphthalene OR: 2.498, 95% CI: 1.524–4.095; 3-hydroxyfluorene OR: 2.752, 95% CI: 2.100–3.608; 2-hydroxyfluorene OR: 3.461, 95% CI: 2.438–4.914; 1-hydroxyphenanthrene OR: 2.442, 95% CI: 1.515–3.937; 1-hydroxypyrene OR: 2.828, 95% CI: 1.728–4.629; 2 & 3-hydroxyphenanthrene OR: 3.690, 95% CI: 2.309–5.896). Of the metals, only urinary cadmium showed a statistically significant positive association (OR: 2.435, 95% CI: 1.401–4.235) with chronic bronchitis. No other metals or arsenic were correlated with chronic bronchitis. Seven forms of urinary PAHs, cadmium, and several demographic factors were associated with chronic bronchitis.
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