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The role of dietary factors on blood lead concentration in children and adolescents - Results from the nationally representative German Environmental Survey 2014–2017 (GerES V)
2022
Hahn, Domenica | Vogel, Nina | Höra, Christian | Kämpfe, Alexander | Schmied-Tobies, Maria | Göen, Thomas | Greiner, Annette | Aigner, Annette | Kolossa-Gehring, Marike
In industrialized nations, human lead exposure has decreased significantly in recent decades. Nevertheless, due to its toxic effects, this heavy metal remains a public health concern with children and adolescents being particularly at risk. In Europe nowadays, oral intake via food and drinking water is the predominant exposure pathway for lead. The objective of the present study was to investigate the association between dietary factors and blood lead (PbB) level of 3- to 17-year-old children and adolescents living in Germany, using data from the fifth German Environmental Health Survey (GerES V) and the Child and Adolescent Health Survey (KiGGS Wave 2). GerES V and KiGGS Wave 2 are two national population-representative studies conducted between 2014 and 2017, including measurement of lead concentrations in blood from 720 children and adolescents aged 3–17 years (mean age = 10.21, SD age = 4.36). Using multiple linear regression, sociodemographic and environmental characteristics as well as dietary factors could be identified as significant exposure determinants of PbB concentrations. Lead intake via domestic tap water was the strongest predictor of elevated PbB levels with 27.6% (p-value< .001) higher concentrations of highest compared to none lead intake via tap water. Other foods which were found to be relevant to PbB levels were meat, fruit, and fruit juice. While meat or fruit consumption were each associated with about 13% (p-value < .05) lower PbB levels, fruit juice drinking was associated with up to 12.2% (p-value = .04) higher PbB levels. In conclusion, results indicate the importance of dietary habits for lead exposure in children and adolescents. To protect vulnerable groups, it is recommended that future research and lead-reducing measures pay more attention to dietary links.
Mostrar más [+] Menos [-]A nationwide survey on the endosulfan residues in Chinese cotton field soil: Occurrence, trend, and ecological risk
2022
Zhang, Yang | Dong, Zhaomin | Peng, Zheng | Zhu, Jingquan | Zhuo, Fuyan | Li, Yang | Ma, Zhihong
The nationwide occurrence of endosulfan residues in cotton fields has not yet been investigated. Therefore, in this study, 202 surface soil samples from 27 cities were collected from cotton fields in 8 major cotton-planting provinces of China, covering more than 97% of the national cotton sown area. The results showed that endosulfan residues were detected in cotton fields throughout the country. The main type of residue found was endosulfan sulfate (ES-sulfate), followed by β-endosulfan and α-endosulfan, with average concentrations of 0.475, 0.129, and 0.048 μg/kg, respectively. Significant spatial variations in the endosulfan residues was noted, and the highest concentration of endosulfan residues was observed in the northwest inland cotton-growing area, followed by that in the Yellow River basin and Yangtze River basin cotton-growing areas. The endosulfan residues showed significant positive correlations with soil organic matter and soil clay contents. The α/β endosulfan ratio was determined to be in the range of 0.02–1.20, indicating that endosulfan residues originated from the endosulfan application performed in historical cotton cultivation efforts. Together with the literature data, the concentrations of α-endosulfan and β-endosulfan residues peaked in 2015 and 2017, respectively, and showed an overall decreasing trend from 2002 to 2021. The results of the ecological risk assessment suggested that Folsomia candida was most sensitive to endosulfan residues, with 20.8% of the sites presenting a high risk. However, in general, the soil ecological risk of cotton fields across the country was low. Our study demonstrated that China has achieved promising results in controlling the use and pollution of endosulfan, especially after 2014.
Mostrar más [+] Menos [-]Occurrence and distribution of persistent organic pollutants in the liver and muscle of Atlantic blue sharks: Relevance and health risks
2022
Muñoz-Arnanz, Juan | Bartalini, Alice | Alves, Luís | Lemos, Marco FL. | Novais, Sara C. | Jiménez, Begoña
Blue shark score among the most abundant, widely distributed and worldwide consumed elasmobranchs. In this work contents of PCBs, PCDD/Fs and PBDEs were studied by means of GC-HRMS in muscle and liver of sixty blue sharks from the North East Atlantic sampled in 2019. Concentrations relatively similar were found for PCBs and PCDD/Fs in comparison with those in Atlantic specimens from the same area sampled in 2015. In contrast, PBDE loads doubled, likely mirroring the increased environmental presence of these pollutants. This, together with the different congener profiles reported for the same species in other geographical areas, highlighted the blue shark's potential as bioindicator of the degree and fingerprints of regional pollution by POPs. Interesting dissimilarities between muscle and liver concentrations were detected, most likely ascribed to distinct toxicokinetics involved for the different pollutants. Whereas most POPs preferentially accumulated in liver, some did the opposite in muscle. BDE-209 was the most prominent example, being almost negligible its presence in liver (0.3%) while accounting for ca. 14% of the total PBDE content in muscle. Different findings in this regard described for other shark species call for focused research to ascertain the role of the species in this apparent favored metabolization of BDE-209 in the liver. From a consumption perspective, the concentrations found in muscle -the most relevant part in the human diet-for PCBs and dioxin-like POPs were below the EU maximum allowed levels in foodstuff. Conversely, in liver about 58% and 78% of samples overpassed the European levels for tolerable intake of i-PCBs and dioxin POPs, respectively. Concentrations of PBDEs exceeded EQS (0.0085 ng/g w.w.) established by the European Water Framework Directive in 100% and 92% of liver and muscle samples, respectively, which adds to the open debate of such as a reduce value for this current EQS.
Mostrar más [+] Menos [-]Predicting the global environmental distribution of plastic polymers
2022
Hoseini, Maryam | Bond, Tom
This study represents the first quantitative global prediction of the mass distribution of six widespread polymers, plus plastic fibers and rubber across four environmental compartments and 11 sub-compartments. The approach used probabilistic material flow analysis for 2015, with model input values and transfer coefficients between compartments taken from literature. We estimated that 3.2 ± 1.8 Mt/year of polyethylene, 1.3 ± 0.8 Mt/year of polypropylene, 0.5 ± 0.3 Mt/year of polystyrene, 0.3 ± 0.15 Mt/year of polyvinyl chloride, 1.6 ± 0.9 Mt/year of polyethylene terephthalate and 2.4 ± 1.2 Mt/year of plastic fibers enter the environment. Combining all plastic, including rubber, 4.9 ± 1.3, 4.8 ± 1.9 and 1.8 ± 1.2 Mt/year accumulated in the soil, ocean, and freshwater, respectively. Urban soils and ocean shorelines were predicted as hotspots for plastic accumulation, accounting for 33% and 25% of total plastic, respectively. The floor of freshwater systems and the ocean were predicted as hotspots for high density plastic such as polyethylene terephthalate, polyvinyl chloride and plastic fibers. Furthermore, 59% of environmental rubber was predicted to accumulate in soil. The findings of this study provide baseline data for quantifying plastic transport and accumulation, which can inform future ecotoxicity studies and risk assessments, as well as targeting efforts to mitigate plastic pollution.
Mostrar más [+] Menos [-]Biomedical and catalytic applications of agri-based biosynthesized silver nanoparticles
2022
Garg, Rajni | Rani, Priya | Garg, Rishav | Khan, Mohammad Amir | Khan, Nadeem Ahmad | Khan, Afzal Husain | Américo-Pinheiro, Juliana Heloisa Pinê
Nanotechnology has been recognized as the emerging field for the synthesis, designing, and manipulation of particle structure at the nanoscale. Its rapid development is also expected to revolutionize industries such as applied physics, mechanics, chemistry, and electronics engineering with suitably tailoring various nanomaterials. Inorganic nanoparticles such as silver nanoparticles (Ag-NPs) have garnered more interest with their diverse applications. In correspondence to green chemistry, researchers prioritize green synthetic techniques over conventional ones due to their eco-friendly and sustainable potential. Green-synthesized NPs have proven more beneficial than those synthesized by conventional methods because of capping by secondary metabolites. The present study reviews the various means being used by the researchers for the green synthesis of Ag-NPs. The morphological characteristics of these NPs as obtained from numerous characterization techniques have been explored. The potential applications of bio-synthesized Ag-NPs viz. Antimicrobial, antioxidant, catalytic, and water remediation along with the plausible mechanisms have been discussed. In addition, toxicity analysis and biomedical applications of these NPs have also been reviewed to provide a detailed overview. The study signifies that biosynthesized Ag-NPs can be efficiently used for various applications in the biomedical and industrial sectors as an environment-friendly and efficient tool.
Mostrar más [+] Menos [-]Urban edge trees: Urban form and meteorology drive elemental carbon deposition to canopies and soils
2022
Ponette-González, Alexandra G. | Chen, Dongmei | Elderbrock, Evan | Rindy, Jenna E. | Barrett, Tate E. | Luce, Brett W. | Lee, Jun-Hak | Ko, Yekang | Weathers, Kathleen C.
Urban tree canopies are a significant sink for atmospheric elemental carbon (EC)––an air pollutant that is a powerful climate-forcing agent and threat to human health. Understanding what controls EC deposition to urban trees is therefore important for evaluating the potential role of vegetation in air pollution mitigation strategies. We estimated wet, dry, and throughfall EC deposition for oak trees at 53 sites in Denton, TX. Spatial data and airborne discrete-return LiDAR were used to compute predictors of EC deposition, including urban form characteristics, and meteorologic and topographic factors. Dry and throughfall EC deposition varied 14-fold across this urban ecosystem and exhibited significant variability from spring to fall. Generalized additive modeling and multiple linear regression analyses showed that urban form strongly influenced tree-scale variability in dry EC deposition: traffic count as well as road length and building height within 100–150 m of trees were positively related to leaf-scale dry deposition. Rainfall amount and extreme wind-driven rain from the direction of major pollution sources were significant drivers of throughfall EC. Our findings indicate that complex configurations of roads, buildings, and vegetation produce “urban edge trees” that contribute to heterogeneous EC deposition patterns across urban systems, with implications for greenspace planning.
Mostrar más [+] Menos [-]Development of physiologically-based toxicokinetic-toxicodynamic (PBTK-TD) model for 4-nonylphenol (4-NP) reflecting physiological changes according to age in males: Application as a new risk assessment tool with a focus on toxicodynamics
2022
Jeong, Seung-Hyun | Jang, Ji-Hun | Lee, Yong-Bok
Environmental exposure to 4-nonylphenol (4-NP) is extensive, and studies related to human risk assessment must continue. Especially, prediction of toxicodynamics (TDs) related to reproductive toxicity in males is very important in risk-level assessment and management of 4-NP. This study aimed to develop a physiologically-based-toxicokinetic-toxicodynamic (PBTK-TD) model that added a TD prostate model to the previously reported 4-n-nonylphenol (4-n-NP) physiologically-based-pharmacokinetic (PBPK) model. Modeling was performed under the assumption of similar TKs between 4-n-NP and 4-NP because TK experiments on 4-NP, a random-mixture, are practically difficult. This study was very important to quantitatively predict the TKs and TDs of 4-NP by age at exposure using an advanced PBTK-TD model that reflected physiological-changes according to age. TD-modeling was performed based on the reported toxic effects of 4-NP on RWPE-1 cells, a human-prostate-epithelial-cell-line. Through a meta-analysis of reported human physiological data, body weight, tissue volume, and blood flow rate patterns according to age were mathematically modeled. These relationships were reflected in the PBTK-TD model for 4-NP so that the 4-NP TK and TD changes according to age and their differences could be confirmed. Differences in TK and TD parameters of 4-NP at various ages were not large, within 3.61-fold. Point-of-departure (POD) and reference-doses for each age estimated using the model varied as 426.37–795.24 and 42.64–79.52 μg/kg/day, but the differences (in POD or reference doses between ages) were not large, at less than 1.87-times. The PBTK-TD model simulation predicted that even a 100-fold 4-NP PODₘₐₙ dose would not have large toxicity to the prostate. With a focus on TDs, the predicted maximum possible exposure of 4-NP was as high as 6.06–23.60 mg/kg/day. Several toxicity-related values estimated by the dose-response curve were higher than those calculated, depending upon the PK or TK, which would be useful as a new exposure limit for prostate toxicity of 4-NP.
Mostrar más [+] Menos [-]Visualization and (Semi-)quantification of submicrometer plastics through scanning electron microscopy and time-of-flight secondary ion mass spectrometry
2022
Chou, Shih-Hsuan | Chuang, Yung-Kun | Lee, Chi-Ming | Zhang, Yushan | Jhang, Ya-Jhu | Yeh, Ching-Wen | Wu, Tai-Sing | Chuang, Chun-Yu | Hsiao, I-Lun
Increasing numbers of studies have demonstrated the existence of nanoplastics (1–999 nm) in the environment and commercial products, but the current technologies for detecting and quantifying nanoplastics are still developing. Herein, we present a combination of two techniques, e.g., scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), to analyze submicron-sized plastics. A drop-casting of a 20-nL particle suspension on a Piranha solution-cleaned silicon wafer with dry ice incubation and subsequent freeze-drying was used to suppress the coffee-ring effect. SEM images were used to quantify particles, and this technique is applicable for 0.195–1.04-μm polystyrene (PS), 0.311-μm polyethylene terephthalate (PET), and 0.344-μm polyethylene (PE) at a minimum concentration of 2.49 × 10⁹ particles/mL. ToF-SIMS could not quantify the particle number, while it could semi-quantitatively estimate number ratios of submicron PE, PET, polyvinyl chloride (PVC), and PS particles in the mixture. Analysis of submicron plastics released from three hot water-steeped teabags (respectively made of PET/PE, polylactic acid (PLA), and PET) was revisited. The SEM-derived sizes and particle numbers were comparable to those measured by a nanoparticle tracking analysis (NTA) regardless of whether or not the hydro-soluble oligomers were removed. ToF-SIMS further confirmed the number ratios of different particles from a PET/PE composite teabag leachate. This method shows potential for application in analyzing more-complex plastic particles released from food contact materials.
Mostrar más [+] Menos [-]Synthesis of dye-sensitized TiO2/Ag doped nano-composites using UV photoreduction process for phenol degradation: A comparative study
2022
Behera, Amit Kumar | Shadangi, Krushna Prasad | Sarangi, Prakash Kumar
This study investigates a comparison between the photocatalytic action of two nanocomposites (TiO₂ and TiO₂(Ag) doped) on the degradation of phenol from water. The nanocomposites were synthesized by the UV photo-reduction process to get a silver metal loading of 0.25, 0.5, 0.75, and 1% (w/w). In addition to this, Eriochrome Cyanine Red (ECR) and Eosin Yellow (EY) both anionic dyes were used for sensitization of Ag-doped TiO₂ photo-catalyst such as TiO₂(Ag)ECR and TiO₂(Ag)EY. The TiO₂(Ag-1.0)EY photo-catalyst indicated higher absorbance compared to the TiO₂(Ag-1.0)ECR in the 400–700 nm range (visible range). The degradation of phenol was tested by varying the pH, silver loading and catalyst dosage. The maximum degradation of phenol was 98% in 180 min at pH 7 in presence of 1% (w/w) silver loading with 0.5 gL⁻¹ dosage of photo-catalyst TiO₂(Ag-1.0)EY. At this condition, the reduction in the phenol concentration was noticed from 20 mg/L to 0.4 mg/L.
Mostrar más [+] Menos [-]A large geographic-scale characterization of organochlorine pesticides (OCPs) in surface sediments and multiple aquatic foods of inland freshwater aquaculture ponds in China: Co-occurrence, source and risk assessment
2022
Chen, Lu | Qian, Yong-Zhong | Jia, Qi | Weng, Rui | Zhang, Xinglian | Li, Yun | Qiu, Jing
Inland freshwater aquaculture ponds (IFAPs) represent the key component of the global lentic freshwater environment and are increasingly important for global aquaculture production, yet the occurrence of organochlorine pesticides (OCPs) in these pond systems remains largely unknown. Here, we characterized the residual concentrations of 19 individual OCPs in sediments and in cultured fish and crustacean species (crabs, shrimp, crayfish and lobster), which were on-spot sampled from the IFAPs at a large region-scale in China. The total OCP levels in sediments varied dramatically between regions. Crabs presented the greatest OCP contamination among the studied species. Dichlorodiphenyltrichloroethanes (DDTs) was the dominating contaminant in sediments and crabs and its stable degradation products 4,4′-DDE and 4,4′-DDD were co-occurrent between these two compartments. The diagnostic ratio analysis indicated fresh inputs of DDTs, lindane and aldrin in multiple regions, which may be resulted from agricultural soil erosion, surface runoff and local anthropogenic activities. Ecological impacts of these pesticides could be expected at some sites due to their levels in sediments above the risk level. Risk assessment based on the OCP levels corrected by the cooking loss revealed that daily consumption of the IFAPs-derived aquatic foods may pose carcinogenic risks in humans.
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