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The distributions of three fungicides in vegetables and their potential health risks in Zhejiang, China: A 3-year study (2015–2017) Полный текст
2020
Lin, Shu | Tang, Tao | Cang, Tao | Yu, Shuqing | Ying, Zeteng | Gu, Sijia | Zhang, Quan
Fungicides have been extensively used around the world in agriculture due to their effectiveness of sterilization. Recent evidences have shown that fungicides would exert a negative effect on gut microbiota and result in gut microbiota dysbiosis and metabolism disorder on non-target organisms and even humans. However, research on residues and potential health risks of fungicides in daily consumed vegetables has received less attention compared to insecticides. In this study, we studied three widely applied fungicides, procymidone, dimethomorph, and azoxystrobin, in China. We collected 551 samples of 10 different vegetables in 11 cities from Zhejiang province during 2015–2017. Three fungicides were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average apparent recoveries of three fungicides ranged from 84.2% to 110% with the relative standard deviations lower than 10%. The LOD values of procymidone, dimethomorph, and azoxystrobin was 2, 0.09, and 1 μg/kg, respectively. The levels of procymidone, dimethomorph, and azoxystrobin in those vegetables ranged from ND-875, ND-238, and ND-76 μg/kg, respectively. The highest mean concentrations of procymidone, dimethomorph, and azoxystrobin were found in eggplant (68 μg/kg), spinach (16.4 μg/kg), and kidney bean (4 μg/kg), respectively. Tomato (62.6% of samples), eggplant (44.3% of samples), and cucumber (41.6% of samples) were most frequently detected with fungicides. Solanaceous fruit vegetables have the highest detection rate than other vegetables, and fungicides were most frequently detected in winter. The mean concentrations of three fungicides in different vegetables were all below the maximum residue limits for the national food safety standards of China, and the health risks resulting from consuming those vegetables in adults and children were all within the safe ranges. The data provided here clarify the distributions of fungicides in commonly consumed vegetables and their potential health risks.
Показать больше [+] Меньше [-]Genome-wide DNA methylation analysis reveals significant impact of long-term ambient air pollution exposure on biological functions related to mitochondria and immune response Полный текст
2020
Wang, Maiqiu | Zhao, Junsheng | Wang, Yan | Mao, Ying | Chao, Shin-Yi | Huang, Peng | Liu, Qiang | Ma, Yunlong | Yao, Yinghao | Yang, Zhongli | Yuan, Wenji | Cui, Wenyan | Payne, Thomas J. | Li, Ming D.
Exposure to long-term ambient air pollution is believed to have adverse effects on human health. However, the mechanisms underlying these impacts are poorly understood. DNA methylation, a crucial epigenetic modification, is susceptible to environmental factors and likely involved in these processes. We conducted a whole-genome bisulfite sequencing study on 120 participants from a highly polluted region (HPR) and a less polluted region (LPR) in China, where the HPR had much higher concentrations of five air pollutants (PM₂.₅, PM₁₀, SO₂, NO₂, and CO) (fold difference 1.6 to 6.6 times; P value 1.80E-07 to 3.19E-23). Genome-wide methylation analysis revealed 371 DMRs in subjects from the two areas and these DMRs were located primarily in gene regulatory elements such as promoters and enhancers. Gene enrichment analysis showed that DMR-related genes were significantly enriched in diseases related to pulmonary disorders and cancers and in biological processes related to mitochondrial assembly and cytokine production. Further, HPR participants showed a higher mtDNA copy number. Of those identified DMRs, 15 were significantly correlated with mtDNA copy number. Finally, cytokine assay indicated that an increased plasma interleukin-5 level was associated with greater air pollution. Taken together, our findings suggest that exposure to long-term ambient air pollution can lead to alterations in DNA methylation whose functions relate to mitochondria and immune responses.
Показать больше [+] Меньше [-]Diurnal and temporal changes in air pollution during COVID-19 strict lockdown over different regions of India Полный текст
2020
Singh, Vikas | Singh, Shweta | Biswal, Akash | Kesarkar, Amit P. | Mor, Suman | Ravindra, Khaiwal
Lockdown measures to contain COVID-19 pandemic has resulted in a considerable change in air pollution worldwide. We estimate the temporal and diurnal changes of the six criteria air pollutants, including particulate matter (PM₂.₅ and PM₁₀) and gaseous pollutants (NO₂, O₃, CO, and SO₂) during lockdown (25ᵗʰ March – 3ʳᵈ May 2020) across regions of India using the observations from 134 real-time monitoring sites of Central Pollution Control Board (CPCB). Significant reduction in PM₂.₅, PM₁₀, NO₂, and CO has been found in all the regions during the lockdown. SO₂ showed mixed behavior, with a slight increase at some sites but a comparatively significant decrease at other locations. O₃ also showed a mixed variation with a mild increase in IGP and a decrease in the South. The absolute decrease in PM₂.₅, PM₁₀, and NO₂ was observed during peak morning traffic hours (08–10 Hrs) and late evening (20–24 Hrs), but the percentage reduction is almost constant throughout the day. A significant decrease in day-time O₃ has been found over Indo Gangetic plain (IGP) and central India, whereas night-time O₃ has increased over IGP due to less O₃ loss. The most significant reduction (∼40–60%) was found in PM₂.₅ and PM₁₀. The highest decrease in PM was found for the north-west and IGP followed by South and central regions. A considerable reduction (∼30–70%) in NO₂ was found except for a few sites in the central region. A similar pattern was observed for CO having a ∼20–40% reduction. The reduction observed for PM₂.₅, PM₁₀, NO₂, and enhancement in O₃ was proportional to the population density. Delhi’s air quality has improved with a significant reduction in primary pollutants, however, an increase in O₃ was observed. The changes reported during the lockdown are combined effect of changes in the emissions, meteorology, and atmospheric chemistry that requires detailed investigations.
Показать больше [+] Меньше [-]Novel and specific source identification of PAH in urban soils: Alk-PAH-BPCA index and “V”-shape distribution pattern Полный текст
2020
Hindersmann, Benjamin | Förster, Antonia | Achten, Christine
Soils in urban and industrial areas, especially in larger metropolitan areas such as the Ruhr area, Germany, are commonly characterized by severe anthropogenic overprinting due to urbanization processes including land development measures. Such urban soils often contain various anthropogenic substrate admixtures, like ash, coal, tailings, building rubble, industrial waste materials, as well as urban dust, soot, fly ash, and others. These admixtures often carry higher contents of pollutants such as polycyclic aromatic hydrocarbons (PAH). Whereas elevated PAH concentrations are commonly attributed to non-point pyrogenic carbon sources like soot and particulate matter, petrogenic PAH sources are still largely neglected in this context.In this study, an extended sample set of 62 samples of PAH source materials and urban soils containing anthropogenic substrate components was investigated by combining extended PAH analysis of 59 PAH, alkylated PAH distributions and benzene polycarboxylic acid (BPCA) analysis with regard to petrogenic and pyrogenic PAH source identification. For more reliability of source apportionment by a more integrative signal, the alkylated PAH distributions of different PAH groups were combined according to their degrees of alkylation. Based on this combination, a new PAH alkylation index (ΣC0/(ΣC0+ΣC2)) was derived, which considers, in contrast to commonly used single PAH ratios, a series of non-alkylated and alkylated PAH.By comparison of this PAH alkylation index with the degree of aromatic condensation a new robust and economic method for identifying petrogenic, pyrogenic and mixed PAH sources within soil samples and sediments was developed. It is shown that coal and coal ash particles are a not negligible PAH source in urban soils of mining-dominated regions and can make up a large proportion of the anthropogenic substrate components encountered.Further analyses of samples with defined levels of petrogenic and pyrogenic PAH are necessary to finally evaluate the usefulness of this proposed new PAH-BPCA approach.
Показать больше [+] Меньше [-]Development of a comprehensive understanding of aggregation-settling movement of CeO2 nanoparticles in natural waters Полный текст
2020
Lv, Bowen | Wang, Chao | Hou, Jun | Wang, Peifang | Miao, Lingzhan | Xing, Baoshan
Parameters such as the settling rate, aggregation rate, and collision frequency in predictive models used to describe the fate of nanoparticles (NPs) are very important for the risk assessment of NPs in the environment. In this study, CeO₂ NPs were chosen as the model particles to investigate such parameters through aggregation-settling experiments under environmentally relevant conditions. The results indicate that natural colloids (Ncs) have no effect on the settling of NPs in seawaters, whereas they stabilize the NPs at a low initial particle concentration and promote the heteroaggregation of NPs at a high initial particle concentration in lake waters. In all cases, a suspended sediment absorbs the NPs and Ncs as mixed aggregates, resulting in a rapid settling. Furthermore, the calculation results of the model indicate that the shear force increases the collision frequency of the NPs by 4–5 orders of magnitude higher than that in quiescent waters. However, the break-up effect by the shear force is more obvious, namely, the shear force hinders the aggregation of NPs in natural waters, instead of promoting aggregation. Remarkably, a negative value of the dis-heteroaggregation rate based on the combined von Smoluchowski–Stokes equation can reflect the hindering effect on the aggregation process. The results of this study will provide scientific and accurate guidance for the parameter selection in the existing prediction model and contribute to a prediction of the fate and transport of NPs in the environment.
Показать больше [+] Меньше [-]Exposure to Benzo[a]pyrene impairs the corpus luteum vascular network in rats during early pregnancy Полный текст
2020
Liu, Min | Deng, Ting | He, Junlin | Ding, Yubin | Liu, Xueqing | Xu, Hanting | Gao, Rufei | Mu, Xinyi | Geng, Yanqing | Liu, Taihang | Wang, Yingxiong | Chen, Xuemei
Benzo [a]pyrene (BaP) is a well-known endocrine disruptor. Exposure to BaP is known to impair embryo implantation. The corpus luteum (CL), the primary source of progesterone during early pregnancy, plays a pivotal role in embryo implantation and pregnancy maintenance. The inappropriate luteal function may result in implantation failure and spontaneous abortions. However, the effect of BaP on CL remains unknown. This study investigated the deleterious effects of BaP on the structure and function of CL during early pregnancy. Pregnant rats were dosed with BaP at 0.2 mg.kg-1. d from day 1 (D1) to day 9 (D9) of gestation. We found that BaP reduced the number of CLs, disturbed the secretion of steroid and impacted the luteal vascular networks. BaP significantly decreased the angiogenesis factor (VEGFR, Ang-1 and Tie2) and increased the anti-angiogenic factor THBS1. Inhibited THBS1 function by LSKL partially rescued the angiogenesis defect caused by BaP. In vitro, BaP metabolite BPDE also interfered the expression levels of angiogenesis-related factors in HUVECs and impaired the angiogenesis, whereas supplemented with rAng-1 can alleviate the anti-angiogenic effect of BPDE. Furthermore, Notch signaling molecules, including Notch1, Dll4, Jag1 and Hey2, which are essential for the establishment and maturation of vascular networks, were affected by BaP exposure. Collectively, BaP broke the molecular regulatory balance between luteal angiogenesis and vascular maturation, impaired the construction of luteal vascular networks, and further affected luteal formation and endocrine function during early pregnancy. Our findings might provide new insight into the relationship between BaP and luteal insufficiency in early pregnancy. These data also give a new line of evidence for curtailing BaP emissions and protecting the women of childbearing age from occupational exposure.
Показать больше [+] Меньше [-]Confidence intervals and sample size for estimating the prevalence of plastic debris in seabird nests Полный текст
2020
Confidence intervals and sample size for estimating the prevalence of plastic debris in seabird nests Полный текст
2020
Evidence is accumulating about the impacts of plastics on marine life. The prevalence of plastics in seabird nests has been used as an indicator of levels of this pollutant in the ocean. However, the lack of a framework for defining sample sizes and errors associated with estimating the prevalence of plastic in nests prevents researchers from optimising time and reducing impacts of fieldwork. We present a method to determine the confidence intervals for the prevalence of debris in seabird nests and provide, for the first time, information on the prevalence of these items in nests of the Hartlaub’s gull Larus hartlaubii, the African penguin Spheniscus demersus, the great white pelican Pelecanus onocrotalus, and the white-breasted cormorant Phalacrocorax lucidus in South Africa. The method, based on observations and resampling simulations and tested here for nests of 12 seabird species from 15 locations worldwide, allows for straightforward hypothesis testing. Appropriate sample sizes can be defined by combining this method with a Bayesian approach. We show that precise estimates of prevalence of debris in nests can be obtained by sampling around 250 nests. Smaller sample sizes can be useful for obtaining rough estimates. For the Hartlaub’s gull, the African penguin, the great white pelican, and the white-breasted cormorant, debris were present in 0.75%, 3.00%, 6.41%, and 25.62% of the respective nests. Our approach will help researchers to determine errors associated with the prevalence of debris recorded in seabird nests and to optimise time and costs spent collecting data. It can also be applied to estimate confidence intervals and define sample sizes for assessing prevalence of plastic ingestion by any organism.
Показать больше [+] Меньше [-]Global dataset on the presence of debris in nests of seabirds Полный текст
2020
Tavares, Davi Castro
This dataset includes information on the presence of plastic debris in nests of 14 seabird species from different locations in the world. It also includes generated data for simulating bird species with high levels of prevalence of debris in nests. Methods related to data collection are described in Tavares et al. (2020). Confidence intervals and sample size for estimating the prevalence of plastic debris in seabird nests. Environmental Pollution. https://doi.org/10.1016/j.envpol.2020.114394
Показать больше [+] Меньше [-]Exposure to air pollution during the first 1000 days of life and subsequent health service and medication usage in children Полный текст
2020
Evidence of health effects following early life exposure to short-to-medium duration of high pollution levels is extremely limited.We aimed to evaluate the associations between: 1. intrauterine exposure to fine particulate matter (PM2.5) from coal mine fire emissions and the frequencies of general practitioner attendances and dispensations of prescribed asthma inhalers, steroid skin creams, and antibiotics during the first year of life; 2. infant exposure and those outcomes during the year following the fire.All participants were recruited from the Latrobe Valley of Victoria, Australia. Participants’ 24-h average and hourly peak mine fire-specific PM2.5 exposures from 09/02/2014 to 31/03/2014 were estimated using chemical transport modelling. Outcome data were obtained from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme from each child’s birth to 31/12/2016. We used negative binomial and logistic regression models to independently assess risks of the outcomes associated with every 10 and 100 μg m−3 increase in average or peak PM2.5 exposure, respectively, while adjusting for potential confounders.We included 286 of 311 children whose parents consented to be linked, comprising 77 with no exposure, 88 with intrauterine exposure and 121 with exposure in infancy. 10- and 100- μg m−3 increases in average and peak PM2.5 exposure during infancy were associated with greater incidence of antibiotics being dispensed during the year following the fire: the adjusted incidence rate ratios were 1.24 (95% CI 1.02, 1.50, p = 0.036) and 1.14 (1.00, 1.31, p = 0.048) respectively. No other significant associations were observed.Exposure to coal mine fire emissions during infancy was associated with increased dispensing of antibiotics. This could reflect increased childhood infections or increased prescriptions of antibiotics in the year following the fire.
Показать больше [+] Меньше [-]Occurrence, source and ecotoxicological risk assessment of pesticides in surface water of Wujin District (northwest of Taihu Lake), China Полный текст
2020
This study investigated the occurrence and distribution of pesticides in surface water (lakes, major rivers and tributaries) and potential discharge sources (fish ponds, livestock and poultry farms, and sewage treatment plants) in Wujin District (northwest of Taihu Lake), Jiangsu province, China. An analytical liquid chromatography-tandem mass spectrometry method was developed for 38 pesticides, which was applied in the monitoring of 240 surface water samples and 76 potential discharge source samples. Eleven insecticides and five fungicides with temporal and spatial variation were detected in surface water. The total pesticide concentrations in surface water in different seasons were as follows: March > August > June > November. The two most polluting and widespread pesticides were carbendazim (maximum concentration 508 ng L⁻¹, detection rate 100%) and imidacloprid (maximum concentration 438 ng L⁻¹, detection rate 88%). Gehu Lake (S46) and Sanshangang River (S12) were seriously polluted water bodies. Seven insecticides and four fungicides were detected in the potential discharge sources; and their composition changed significantly with the seasons. The concentrations of detected organophosphorus pesticides and neonicotinoids (e.g. acetamiprid in March and dichlorvos in November) in a few non-agricultural planting sources were far greater than those detected in surface water, and hence a few fish ponds, livestock and poultry farms, and sewage treatment plants might be the potential discharge sources of pesticides in the surrounding surface water. The estimated input flux of the studied pesticides from upstream rivers to Taihu Lake was 141.95 kg a⁻¹. Furthermore, more attention should be paid to the medium or high aquatic ecotoxicological risk presented by the levels of organophosphorus pesticides, carbamates, and benzimidazoles.
Показать больше [+] Меньше [-]Impacts of a local music festival on fish stress hormone levels and the adjacent underwater soundscape Полный текст
2020
An understudied consequence of coastal urbanization on marine environments is sound pollution. While underwater anthropogenic sounds are recognized as a threat to aquatic organisms, little is known about the effects of above-surface coastal sound pollution on adjacent underwater soundscapes and the organisms inhabiting them. Here, the impact of noise from the 2019 Ultra Music Festival® in Miami, FL, USA was assessed at the University of Miami Experimental Hatchery (UMEH) located directly adjacent to the music festival and on underwater sound levels in Bear Cut, a nearby water channel. In addition, stress hormone levels in fish held at UMEH were measured before and during the festival. Air sound levels recorded at UMEH during the Ultra Music Festival did not exceed 72 dBA and 98 dBC. The subsurface sound intensity levels in the low frequency band increased by 2–3 dB re 1 μPa in the adjacent waterway, Bear Cut, and by 7–9 dB re 1 μPa in the fish tanks at UMEH. Gulf toadfish (Opsanus beta) housed in the UMEH tanks experienced a 4–5 fold increase in plasma cortisol, their main stress hormone, during the first night of the Ultra Music Festival compared to two baseline samples taken 3 weeks and 4 days before Ultra. While this study offers preliminary insights into this type of sound pollution, more research is needed to conclude if Ultra caused a stress response in wild organisms and to fully understand the implications of this type of sound pollution.
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