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1.
J Hazard Mater ; 472: 134519, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38733790

ABSTRACT

Emerging contaminants (ECs) are increasingly recognized as a global threat to biodiversity and ecosystem health. However, the cumulative risks posed by ECs to aquatic organisms and ecosystems, as well as the influence of anthropogenic activities and natural factors on these risks, remain poorly understood. This study assessed the mixed risks of ECs in Dongting Lake, a Ramsar Convention-classified Typically Changing Wetland, to elucidate the major EC classes, key risk drivers, and magnitude of anthropogenic and natural impacts. Results revealed that ECs pose non-negligible acute (30% probability) and chronic (70% probability) mixed risks to aquatic organisms in the freshwater lake ecosystem, with imidacloprid identified as the primary pollutant stressor. Redundancy analysis (RDA) and structural equation modeling (SEM) indicated that cropland and precipitation were major drivers of EC contamination levels and ecological risk. Cropland was positively associated with EC concentrations, while precipitation exhibited a dilution effect. These findings provide critical insights into the ecological risk status and key risk drivers in a typical freshwater lake ecosystem, offering data-driven support for the control and management of ECs in China.


Subject(s)
Lakes , Water Pollutants, Chemical , China , Water Pollutants, Chemical/analysis , Risk Assessment , Rivers/chemistry , Environmental Monitoring , Neonicotinoids/analysis , Neonicotinoids/toxicity , Ecosystem , Nitro Compounds/analysis , Aquatic Organisms
2.
Environ Int ; 188: 108745, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38754244

ABSTRACT

One of the fundamental objectives in ecology is to investigate the ecological processes and associated factors governing the abundance and spatial distribution patterns of biodiversity. However, the reaction of biological communities to environmental degradation remains relatively unknown, even for ecologically crucial communities like macroinvertebrates in aquatic ecosystems. Here, we sampled 117 locations to quantify relative contributions of geographical and environmental factors, including water quality, land use, climate, and hydrological factors, to determine the absolute and relative compositions of macroinvertebrate communities and their spatial distribution in the Yellow River Basin (YRB), the sixth-longest river system on Earth. We assessed relative roles of species sorting and dispersal in determining macroinvertebrate community structure along YRB. Our results demonstrated that alpha and beta diversity indices showed an increase from the up- to low-reaches of YRB. The middle and low-reaches exhibited elevated species diversity and both regions exhibited relatively stable community compositions. The biodiversity of macroinvertebrates was influenced by a combination of geographical factors and environmental variables, with environmental factors predominantly serving as the principal determinants. Results of multiple linear regression and variance decomposition showed that the effect of environmental factors was approximately three times greater than that of spatial factors. These findings provide support for the hypothesis that species sorting, driven by environmental gradients, plays a significant role in shaping the community structure of macroinvertebrates in running water ecosystems at the basin scales. Moreover, the factors contributing to substantial shifts in biodiversity across different segments of YRB indicate that distinct river sections have been influenced by varying stressors, with downstream areas being more susceptible to the impacts of water pollution and urbanization resulting from human activities.


Subject(s)
Biodiversity , Invertebrates , Rivers , Rivers/chemistry , Animals , Invertebrates/classification , Invertebrates/physiology , China , Ecosystem , Environmental Monitoring , Water Quality
3.
J Hazard Mater ; 467: 133642, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38330644

ABSTRACT

Due to their endocrine-disrupting effects and the risks posed in surface waters, in particular by chronic low-dose exposure to aquatic organisms, phthalate esters (PAEs) have received significant attention. However, most assessments of risks posed by PAEs were performed at a selection level, and thus limited by empirical data on toxic effects and potencies. A quantitative structure activity relationship (QSAR) and interspecies correlation estimation (ICE) model was constructed to estimate hazardous concentrations (HCs) of selected PAEs to aquatic organisms, then they were used to conduct a multiple-level environmental risk assessment for PAEs in surface waters of China. Values of hazardous concentration for 5% of species (HC5s), based on acute lethality, estimated by use of the QSAR-ICE model were within 1.25-fold of HC5 values derived from empirical data on toxic potency, indicating that the QSAR-ICE model predicts the toxicity of these three PAEs with sufficient accuracy. The five selected PAEs may be commonly measured in China surface waters at concentrations between ng/L and µg/L. Risk quotients according to median concentrations of the five PAEs ranged from 3.24 for di(2-ethylhexhyl) phthalate (DEHP) to 4.10 × 10-3 for dimethyl phthalate (DMP). DEHP and dibutyl phthalate (DBP) had risks to the most vulnerable aquatic biota, with the frequency of exceedances of the predicted no-effect concentration (PNECs) of 75.5% and 38.0%, respectively. DEHP and DBP were identified as having "high" or "moderate" risks. Results of the joint probability curves (JPC) method indicated DEHP posed "intermediate" risk to freshwater species with a maximum risk product of 5.98%. The multiple level system introduced in this study can be used to prioritize chemicals and other new pollutant in the aquatic ecological.


Subject(s)
Diethylhexyl Phthalate , Phthalic Acids , Water Pollutants, Chemical , Diethylhexyl Phthalate/toxicity , Quantitative Structure-Activity Relationship , Rivers/chemistry , Esters/toxicity , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Phthalic Acids/toxicity , Dibutyl Phthalate/toxicity , Risk Assessment , China
4.
China CDC Wkly ; 5(28): 619-624, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37520446

ABSTRACT

What is already known about this topic?: Research on community-based smoking cessation interventions in China is still in its early stages. Most existing studies have focused on a limited number of communities and have primarily examined interventions conducted by study teams rather than broader community initiatives. What is added by this report?: The three-month continuous abstinence rate for the intervention group (21.61%) was significantly higher than that for the control group (8.98%). Comprehensive community-based smoking cessation interventions, administered by trained physicians at community health service centers and supported by community workers, have shown effectiveness in improving a variety of outcomes among community smokers. What are the implications for public health practice?: The feasibility and effectiveness of comprehensive community-based smoking cessation interventions make them a valuable addition to existing cessation services in China. Wider implementation of these interventions should be pursued as a complementary approach to current efforts to reduce smoking rates in China.

5.
China CDC Wkly ; 5(21): 459-463, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37405263

ABSTRACT

What is already known about this topic?: In 2018, unassisted smoking cessation (USC) was the predominant method for quitting smoking among Chinese adult smokers, accounting for 90.1% of cases. The utilization of professional smoking cessation support was comparatively low in this population. What is added by this report?: In 2020, the prevalence of USC methods increased to 93.1%. Concurrently, there was a slight increase in the utilization of pharmaceuticals (from 4.6% in 2018 to 5.5% in 2020) and counseling and quit line services (from 3.2% in 2018 to 7.5% in 2020). On the other hand, the use of e-cigarettes as a cessation aid decreased from 14.9% in 2018 to 9.8% in 2020. Smokers aged 15-24 years old were more likely to rely on pharmaceutical interventions (7.9%), and less likely to choose USC methods (79.0%). What are the implications for public health practice?: The promotion of professional cessation support is essential for enhancing smoking cessation rates.

6.
J Environ Manage ; 342: 118344, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37320921

ABSTRACT

Freshwater biodiversity and ecosystem services might decline due to exposure to chemicals. However, researchers have devoted much attention to the potential risks of emerging contaminants, while placing less effort on historical pollutants, such as the surfactant, linear-alkylbenzene-sulfonate (LAS), which is a major component of widely used synthetic detergents worldwide. In this study, a multilevel risk assessment approach was used to assess risks posed by LAS to aquatic organisms, on a wide spatial scale, based on various assessment endpoints. Additionally, bottom-up approaches were used to assess contributions of LAS source discharges to aquatic environments. Concentrations of LAS in surface waters of China ranged from less than the limit of detection to 14,200 µg/L. The predicted no effect concentration (PNEC) based on adverse effects on reproduction is 15 µg/L, which is slightly less than the PNEC based on other endpoints. 99% of surface waters in Chaohu Lake and the Hai River (Ch: Haihe) were predicted to pose a risk to growth of aquatic organisms, with a protection threshold of 5% of species (HC5). Discharges of LAS were estimated using activity data and emission factors for 280 major cities in the basin. Rural domestic sources were the main source of LAS to surface waters. These outcomes provided a process for developing comprehensive management and control approaches to help researchers and policymakers effectively manage water resources affected by increasing concentrations of LAS.


Subject(s)
Alkanesulfonic Acids , Environmental Pollutants , Ecosystem , Lakes
7.
Tob Induc Dis ; 20: 89, 2022.
Article in English | MEDLINE | ID: mdl-36330276

ABSTRACT

INTRODUCTION: Preventing youth from tobacco use is a priority for tobacco control in China, and the government has taken many measures such as introducing tobacco control in the health education curriculum, banning smoking in school, promoting smoke-free household, and advocacy campaigns. The objective of this study was to understand the availability and affordability of cigarettes for middle school (MS) and high school (HS) students in China. METHODS: The data were extracted from the 2019 China National Youth Tobacco Survey, which was a school-based cross-sectional survey with a nationally representative sample of 288192 MS and HS students. The survey employed a randomized multistage stratified cluster sampling design with probability proportional to size sampling method and used an anonymous self-administrated questionnaire to collect data. The availability and affordability of cigarettes were analyzed, and all parameter estimates were weighted to account for the complex sampling design. RESULTS: In 2019, an estimated 80.5% of current smokers who were aged <18 years bought cigarettes in the past 30 days. Among them, 83.3% (83.0% of males and 85.2% of females; and 76.5% in MS and 87.6% in HS) had not been refused purchase of cigarettes because they were underage, with 84.1% in urban and 82.9% in rural areas, and 87.3% in central, 83.4% in eastern, and 80.5% in western regions of China. Among current smokers who bought cigarettes in the past 30 days, 77.3% had bought a pack of cigarettes (20 cigarettes) costing >10 RMB and at least 61.4% had more pocket money per week than the cost of a pack of cigarettes. Although 84.2% of current smokers bought cigarettes by the pack, 9.2% of current smokers reported that they bought cigarettes as sticks. CONCLUSIONS: Although the youth smoking rate dropped down from 2014 to 2019, the proportion of youth smokers that bought cigarettes was still high in China. Due to the high amount of pocket money, the current cigarette price was not an effective price barrier to prevent youth smoking. Selling cigarettes by the stick worsens the situation. Strengthening the enforcement of the 2021 Law on the Protection of Minors, increasing tobacco taxes and prices, and forbidding the selling of cigarette sticks, might assist the progress in youth tobacco control.

8.
Environ Int ; 167: 107367, 2022 09.
Article in English | MEDLINE | ID: mdl-35944286

ABSTRACT

Alkylphenols (APs) are ubiquitous and generally present in higher residue levels in the environment. The present work focuses on the development of a set of in silico models to predict the aquatic toxicity of APs with incomplete/unknown toxicity data in aquatic environments. To achieve this, a QSAR-ICE-SSD model was constructed for aquatic organisms by combining quantitative structure-activity relationship (QSAR), interspecies correlation estimation (ICE), and species sensitivity distribution (SSD) models in order to obtain the hazardous concentrations (HCs) of selected APs. The research indicated that the keywords "alkylphenol" and "nonylphenol" were most commonly studied. The selected ICE models were robust (R2: 0.70-0.99; p-value < 0.01). All models had a high reliability cross- validation success rates (>75%), and the HC5 predicted with the QSAR-ICE-SSD model was 2-fold than that derived with measured experimental data. The HC5 values demonstrated nearly linear decreasing trend from 2-MP to 4-HTP, while the decreasing trend from 4-HTP to 4-DP became shallower, indicates that the toxicity of APs to aquatic organisms increases with the addition of alkyl carbon chain lengths. The ecological risks assessment (ERA) of APs revealed that aquatic organisms were at risk from exposure to 4-NP at most river stations (the highest risk quotient (RQ) = 1.51), with the highest relative risk associated with 2.9% of 4-NP detected in 82.9% of the sampling sites. The targeted APs posed potential ecological risks in the Yongding and Beiyun River according to the mixture ERA. The potential application of QSAR-ICE-SSD models could satisfy the immediate needs for HC5 derivations without the need for additional in vivo testing.


Subject(s)
Rivers , Water Pollutants, Chemical , Aquatic Organisms , Quantitative Structure-Activity Relationship , Reproducibility of Results , Risk Assessment , Species Specificity , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
9.
China CDC Wkly ; 4(21): 448-451, 2022 May 27.
Article in English | MEDLINE | ID: mdl-35686046

ABSTRACT

What is already known about this topic?: Previous studies about tobacco use among college students in China were conducted at the school level or city level, with fewer than 5,000 students participating. What is added by this report?: In 2021, China CDC conducted a national tobacco survey targeting students enrolled in the public higher education system. Overall, 124,119 students from 220 colleges and universities in 31 provincial-level administrative divisions participated in this survey. Current cigarette smoking, current daily smoking, willingness to quit, and smoking cessation among college students were explored. What are the implications for public health practice?: The current daily cigarette smoking rate of college students was significantly higher than that of senior high school students, especially higher vocational college students. Tobacco control interventions, such as a smoke-free school policy and smoking cessation services, need to be reinforced on college campuses.

10.
China CDC Wkly ; 4(21): 441-447, 2022 May 27.
Article in English | MEDLINE | ID: mdl-35686047

ABSTRACT

What is already known about this topic?: In 2019, China CDC conducted the National Youth Tobacco Survey among secondary school students, and the prevalence rates of ever, current, and frequent smoking were 17.9%, 5.9%, and 1.8%, respectively. What is added by this report?: The prevalence rate of cigarette use in males decreased largely from 2019 to 2021 in China, while it increased in 18 provincial-level administrative divisions (PLADs) for females. The tobacco control situation remains challenging among vocational senior high school (VSHS) students. Significant geographical disparities existed in cigarette use. What are the implications for public health practice?: Targeted tobacco control policies aimed at VSHS students are needed, specifically those PLADs with higher smoking rates. Additionally, close attention should be paid to female smokers.

11.
Int J Endocrinol ; 2021: 5561980, 2021.
Article in English | MEDLINE | ID: mdl-34422044

ABSTRACT

Hyperandrogenism is a key pathologic characteristic of polycystic ovarian syndrome (PCOS), and exercise can alleviate the accompanying inflammation and decrease the high androgen levels, but the mechanism is still unclear, so the purpose of this study is to explore the pathophysiologic characteristics of hyperandrogenic PCOS and the mechanism underlying its amelioration with aerobic exercise. Thirty-two female rats were randomly allocated to a normal control group (NC, n = 8), exercise control group (EC, n = 8), PCOS group (PC, n = 8), and PCOS plus exercise group (PE, n = 8). The PC and PE groups were injected with a dehydroepiandrosterone (DHEA) solution to induce the hyperandrogenic PCOS rat model. The EC and PE groups underwent a Masashi swimming protocol (120 min per session, 6 days/week, for 15 days). Results indicated that the concentrations of leptin (LP) in the EC group were significantly lower than those in the NC group (p < 0.05). Compared with the NC group, the levels of testosterone (T), estradiol (E2), follicle-stimulating hormone (FSH), LP, anti-Müllerian hormone (AMH), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and free fatty acids (FFA) were all significantly augmented in the PC group (all p < 0.05). In addition, compared with the NC group, the levels of adiponectin (ADP) were significantly decreased (p < 0.05), and the expression of aromatase cytochrome P450 (P450arom) in ovarian tissue was significantly elevated in the PC group (p < 0.05). The levels of T, FSH, LP, and FFA were also significantly increased in the PE group (p < 0.05). Compared with the PC group, the levels of T and LP in the PE group were significantly diminished (p < 0.05), and the levels of ADP were significantly increased in the PE group (p < 0.05). T was positively correlated with E2, FSH, AMH, LP, TNF-α, IL-6, and FFA levels, while ADP was negatively correlated with LP and E2. These results showed that hyperandrogenism, chronic low-grade inflammation, and leptin resistance may interact to influence the occurrence and development of PCOS. Aerobic exercise can alleviate the internal inflammation by relieving leptin resistance and may mitigate the sex hormone disorder and hyperandrogenism in rats with PCOS by affecting the hypothalamic-pituitary-ovarian axis.

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