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1.
Sci Total Environ ; 915: 170004, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38220018

RESUMEN

Microplastics have become ubiquitous throughout the environment. Humans constantly ingest and inhale microplastics, increasing concerns about the health risks of microplastic exposure. However, limited data impedes a full understanding of the internal exposure to microplastics. Herein, to evaluate microplastic exposure via the respiratory and digestive systems, we used laser direct infrared spectroscopy to identify microplastics >20 µm in size in different human tissues. Consequently, 20-100 µm microplastics were concentrated in all tissues, with polyvinyl chloride (PVC) being the dominant polymer. The highest abundance of microplastics was detected in lung tissue with an average of 14.19 ± 14.57 particles/g, followed by that in the small intestine, large intestine, and tonsil (9.45 ± 13.13, 7.91 ± 7.00, and 6.03 ± 7.37 particles/g, respectively). The abundance of microplastics was also significantly greater in females than in males (p < 0.05). Despite significant diversity, our estimation showed that the lungs accumulated the highest amounts of microplastic. Moreover, PVC particles may cause potential health risks because of their high polymer hazard index and maximal risk level. This study provides evidence regarding the occurrence of microplastics in humans and empirical data to support assessments of the health risks posed by microplastics.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
2.
Water Res ; 245: 120572, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37688860

RESUMEN

Traditional views indicate that eutrophication and subsequent algal blooms favor denitrification and dissimilatory nitrate reduction to ammonium (DNRA) in lake ecosystems. However, lakes tend to show an increasing propensity for inorganic nitrogen (N) limitation as they become more eutrophic. Thus, the influence of further eutrophication on denitrification and DNRA in eutrophic lakes are unclear due to the uncertainty of N availability. To fill this gap, we investigated the genes abundance (AOA, AOB, nirS, nirK and nrfA) and the composition of N-cycling microbes through quantitative PCR and 16S rRNA sequencing analysis, respectively, in 15 shallow eutrophic lakes of the Yangtze-Huaihe River basin, China. The results indicated that denitrification and DNRA rates could be modulated mainly by their functional gene abundances (nirS, nirK and nrfA), followed by the environmental factors (sediment total organic carbon and nitrogen). Denitrification rates significantly increased from slightly to highly eutrophic lakes, but DNRA rates were not. An explanation is that nitrification provided ample nitrate for denitrification, and this cooperative interaction was indicated by the positive correlation of their gene abundances. In addition, Pseudomonas and Anaeromyxobacter was the dominant genus mediated denitrification and DNRA, showing the potential to perform facultative anaerobic and strict anaerobic nitrate reduction, respectively. High level of dissolved oxygen might favor the facultatively aerobic denitrifiers over the obligately anaerobic fermentative DNRA bacteria in these shallow lakes. Chlorophyll a had a weak but positive effect on the gene abundances for nitrification (AOA and AOB). Further eutrophication had an indirect effect on denitrification and DNRA rates through modulating the genes abundances of N-cycling microbes.


Asunto(s)
Compuestos de Amonio , Nitratos , Nitratos/análisis , Lagos/análisis , Desnitrificación , Ecosistema , Clorofila A , ARN Ribosómico 16S/genética , Compuestos Orgánicos , Eutrofización , Nitrógeno/análisis
3.
Water Res ; 244: 120442, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37549546

RESUMEN

Microbial degradation to remove residual antibiotics in wastewater is of growing interest. However, biological treatment of antibiotics may cause resistance dissemination by mutations and horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). In this study, a Mn(Ⅱ)-oxidizing bacterium (MnOB), Pseudomonas aeruginosa MQ2, simultaneously degraded antibiotics, decreased HGT, and mitigated antibiotic resistance mutation. Intracellular Mn(II) levels increased during manganese oxidation, and biogenic manganese oxides (BioMnOx, including Mn(II), Mn(III) and Mn(IV)) tightly coated the cell surface. Mn(II) bio-oxidation mitigated antibiotic resistance acquisition from an E. coli ARG donor and mitigated antibiotic resistance inducement by decreasing conjugative transfer and mutation, respectively. BioMnOx also oxidized ciprofloxacin (1 mg/L) and tetracycline (5 mg/L), respectively removing 93% and 96% within 24 h. Transcriptomic analysis revealed that two new multicopper oxidase and one peroxidase genes are involved in Mn(II) oxidation. Downregulation of SOS response, multidrug resistance and type Ⅳ secretion system related genes explained that Mn(II) and BioMnOx decreased HGT and mitigated resistance mutation by alleviating oxidative stress, which makes recipient cells more vulnerable to ARG acquisition and mutation. A manganese bio-oxidation based reactor was constructed and completely removed tetracycline with environmental concentration within 4-hour hydraulic retention time. Overall, this study suggests that Mn (II) bio-oxidation process could be exploited to control antibiotic contamination and mitigate resistance propagation during water treatment.


Asunto(s)
Antibacterianos , Manganeso , Antibacterianos/farmacología , Escherichia coli/metabolismo , Oxidación-Reducción , Óxidos/metabolismo , Compuestos de Manganeso/metabolismo , Tetraciclina
4.
Sci Total Environ ; 893: 164686, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37290644

RESUMEN

Microplastics have been detected in global aquatic ecosystems, so it is vital to understand the bioaccumulation and biomagnification of microplastics for ecological risk assessment. However, variability between studies, including sampling, pretreatment processes, and polymer identification methods have made it difficult to draw definitive conclusions. Alternatively, the compilation and statistical analysis of available experimental and investigation data provides insight into the fates of microplastics in an aquatic ecosystem. To reduce bias, we performed a systematic literature retrieval and compiled these reports on microplastic abundance in the natural aquatic environment. Our results indicate that microplastics are more abundant in sediments than in water, mussels, and fish. There is a significant correlation between mussels and sediments, but not between water and mussels or between water/sediment and fish. Bioaccumulation of microplastics appears to occur through water, but the route of biomagnification is unclear. More sound evidence is required to fully understand the biomagnification of microplastics in aquatic environments.


Asunto(s)
Bivalvos , Contaminantes Químicos del Agua , Animales , Microplásticos , Ecosistema , Plásticos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Peces , Agua
5.
Huan Jing Ke Xue ; 44(6): 3217-3227, 2023 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-37309940

RESUMEN

In order to understand the occurrence characteristics and ecological risks of pharmaceuticals and personal care products (PPCPs) in surface water and sediments of Hongze Lake and Gaoyou Lake in the lower reaches of the Huaihe River, 43 surface water and sediment samples from 23 sampling sites were collected, and 61 PPCPs were detected in the samples. The concentration level and spatial distribution of target PPCPs in Hongze Lake and Gaoyou Lake were analyzed, the distribution coefficient of typical PPCPs in the water/sediment system in the study area was calculated, and the ecological risk of target PPCPs was evaluated using the entropy method. The results showed that the PPCPs in surface water of Hongze Lake and Gaoyou Lake were 1.56-2534.44 ng·L-1 and 3.32-1027.47 ng·L-1, respectively, and those in sediment were 1.7-926.7 ng·g-1 and 1.02-289.37 ng·g-1, respectively. The concentrations of lincomycin (LIN) in surface water and doxycycline (DOX) in sediment were the highest, and antibiotics were the main components. The spatial distribution of PPCPs was higher in Hongze Lake and lower in Gaoyou Lake. The distribution characteristics of typical PPCPs in the study area showed that typical PPCPs tended to stay in the water phase, and there was a significant correlation between lg Koc and lg Kd, indicating that total organic carbon (TOC) played an important role in the distribution of typical PPCPs in the water/sediment system. The ecological risk assessment results showed that the ecological risk of PPCPs to algae in surface water and sediment was significantly higher than that of fleas and fish, the ecological risk value of PPCPs in surface water was higher than that in sediment, and the ecological risk of Hongze Lake was higher than that of Gaoyou Lake.


Asunto(s)
Lagos , Ríos , Animales , Medición de Riesgo , Antibacterianos , Agua
7.
Ecotoxicol Environ Saf ; 257: 114946, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37105096

RESUMEN

BACKGROUND: Bisphenol A (BPA) is known to exhibit endocrine disrupting activities and is associated with adiposity. We examined the obesogenic effect of prenatal BPA exposure in the present study. METHODS: Pregnant ICR mice were exposed to vehicle or BPA via the drinking water at a dose of 0.5 µg/kg·d throughout the gestation. Obesity-related indexes were investigated in the 12-wk-old offspring. Primary mouse embryonic fibroblasts (MEFs) collected from treated embryos were used to test effects of BPA on adipocyte differentiation. RESULTS: Offspring presented a significantly higher rate of weight gain than the control, with impaired insulin sensitivity and increased adipocyte size. Differentiation of MEFs from BPA-treated mice showed a higher propensity for the adipocyte commitment as well as up-regulation of genes enriched in lipid biosynthesis. TGF-ß signaling pathway was found to modulate obesogenic effect of BPA in MEF model, but estrogen signaling pathway had no effect. CONCLUSIONS: The present study provides strong evidence of the association between prenatal exposure to low dose of BPA and a significant increase in body weight in the offspring mice with a critical role played by TGF-ß signaling pathway. The potential interactions modulating the binding of BPA and TGF-ß that activate its obesogenic effects need to be examined.


Asunto(s)
Adiposidad , Efectos Tardíos de la Exposición Prenatal , Embarazo , Humanos , Animales , Masculino , Ratones , Femenino , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Ratones Endogámicos ICR , Fibroblastos , Obesidad , Compuestos de Bencidrilo/toxicidad
8.
Sci Total Environ ; 859(Pt 1): 160203, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36403833

RESUMEN

Birth weight is an important indicator of future growth and development for newborns. Few studies investigated the potential effects of air pollutants on macrosomia and their susceptible windows. We included 38,971 singleton full-term births from Beijing HaiDian Maternal and Child Health Hospital between 2014 and 2018, and assessed the associations of air pollutants exposure during preconception and pregnancy with macrosomia as well as the corresponding susceptible windows. The concentrations of air pollutants (PM2.5, PM10, SO2, NO2, CO and O3) for participants were calculated by the data from the nearest monitoring stations. Distributed lag models (DLM) incorporating logistic regression models were used to estimate the associations between air pollutants exposure during the 3 months before conception and pregnancy period and the risk of macrosomia, identifying susceptible windows of air pollutants. Weighted quantile sum (WQS) regression was applied to estimate the joint effect of air pollutants. A 10 µg/m3 increase in PM2.5 exposure from 3rd to 8th gestational month was positively associated with the risk of macrosomia, with the strongest effect in the 6th month (OR = 1.010, 95 % CI: 1.002-1.019). For a 10 µg/m3 increase in SO2, the windows of significant exposure were from the 1st preconception month to the 3rd gestational month, with the strongest effect in the 2nd month (OR = 1.030, 95 % CI: 1.010-1.049). We also observed the significant positive associations were in the 5th-8th gestational months for PM10, the 8th-9th gestational months for NO2 and the 3rd-7th gestational months for CO respectively. WQS regression also indicated a positive association between co-exposure to air pollutants and macrosomia. Our results suggest air pollution exposure is associated with increased risk of macrosomia. The windows of exposure for susceptibility to the risk of macrosomia vary between air pollutants. The susceptible exposure windows were middle and late pregnancy for PM, CO and NO2, while for SO2, early pregnancy is the window of vulnerability. Our findings provide the evidence that air pollution exposure is an independent risk factor for macrosomia and a basis for targeted environment policy.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Niño , Femenino , Recién Nacido , Humanos , Embarazo , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Peso al Nacer , Factores de Riesgo , Aumento de Peso , Susceptibilidad a Enfermedades/inducido químicamente , Material Particulado/efectos adversos , Material Particulado/análisis , Exposición Materna/efectos adversos , China/epidemiología
9.
Sci Total Environ ; 856(Pt 1): 159060, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36174702

RESUMEN

Microplastics are ubiquitous in the environment, including in food and drinking water. Consequently, there is growing concern about the human health risks associated with microplastic exposure through diet. However, the occurrence of microplastics in the human body, particularly in mothers and fetuses, is incompletely understood because of the limited amount of data on their presence in the body and the human placenta. This study evaluated the presence and characteristics of microplastics in 17 placentas using laser direct infrared (LD-IR) spectroscopy. Microplastics were detected in all placenta samples, with an average abundance of 2.70 ± 2.65 particles/g and a range of 0.28 to 9.55 particles/g. Among these microplastics, 11 polymer types were identified. The microplastics were mainly composed of polyvinyl chloride (PVC, 43.27 %), polypropylene (PP, 14.55 %), and polybutylene succinate (PBS, 10.90 %). The sizes of these microplastics ranged from 20.34 to 307.29 µm, and most (80.29 %) were smaller than 100 µm. Most of the smaller microplastics were fragments, but fibers dominated the larger microplastics (200-307.29 µm). Interestingly, the majority of PVC and PP were smaller than 200 µm. This study provides a clearer understanding of the shape, size, and nature of microplastics in the human placenta. Importantly, these data also provide crucial information for performing risk assessments of the exposure of fetuses to microplastics in the future.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Femenino , Embarazo , Plásticos , Cloruro de Polivinilo , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Espectrofotometría Infrarroja , Rayos Láser , Placenta/química
10.
Mar Pollut Bull ; 185(Pt A): 114164, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36252440

RESUMEN

The establishment of water quality criteria (WQC) for copper (Cu) was used as the basis for an ecological risk assessment of marine Cu pollution in Liaodong Bay, China. Published ecotoxicity data for Cu were obtained and supplemented with the results of acute Cu toxicity tests. The marine WQC for Cu in Liaodong Bay was developed using a species sensitivity distribution method with a safety factor of 2.0 and the USEPA acute-to-chronic ratio method. The ecological risk of Cu in Liaodong Bay was assessed by comparing the seawater Cu concentrations with the developed WQC. The results of this study showed that the acute and chronic Cu concentrations in Liaodong Bay were 3.31 and 2.18 µg/L, respectively. Comparison of the WQC to Cu concentrations in the bay resulted in risk quotients slightly >1.0 and typically ≤2.0. These data suggest that certain organisms in Liaodong Bay are at risk. These results can assist in the development of a pollution control management approach for the bay.


Asunto(s)
Contaminantes Químicos del Agua , Calidad del Agua , Cobre/toxicidad , Cobre/análisis , Bahías , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , China , Monitoreo del Ambiente
11.
Int J Ophthalmol ; 15(9): 1549-1553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36124180

RESUMEN

AIM: To evaluate the efficacy and safety of HLX04-O, an investigational ophthalmic formulation of HLX04 (bevacizumab biosimilar) for intravitreal injection, as a treatment for wet age-related macular degeneration (wAMD) in a phase 1/2 clinical trial (NCT04993352). METHODS: Eligible patients with wAMD were enrolled to receive HLX04-O intravitreal injections at a dose of 1.25 mg/0.05 mL every four weeks. Efficacy and adverse events were evaluated every month during study visits. RESULTS: A 76-year-old male with wAMD in his left eye participated in the trial and completed six cycles of HLX04-O intravitreal injections. Changes were observed in macular center point thickness (baseline vs last study visit, 437 vs 255 µm) and best-corrected visual acuity letter score (baseline vs last study visit, 36 vs 77) of the affected eye, which indicated an improvement in wAMD over treatment. No adverse events were reported by the data cutoff date. CONCLUSION: HLX04-O at 1.25 mg/0.05 mL every four weeks is well tolerated in this patient, demonstrating promising safety and efficacy in wAMD treatment. Large-scale studies are required to confirm the outcomes.

12.
Ecotoxicol Environ Saf ; 243: 114013, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36037633

RESUMEN

Both fine particulate matter (PM2.5) and ozone (O3) may have adverse effects on human health. However, previous studies on the effects of air pollutants mainly have focused on susceptible population, and evidence on healthy young adults is limited. We aimed to examine the associations of the two main air pollutants (PM2.5 and O3) with lung function, inflammation and oxidative stress in healthy young adults. We recruited 30 healthy young adults for a longitudinal panel study in Beijing and implemented health examination seven times, including lung function (FEV1 and PEF) and biomarkers of inflammation and oxidative stress (i.e. C-reactive protein, CRP; interleukin-6, IL-6; malondialdehyde, MDA) from December 2019 to May 2021. Hourly ambient air pollutants data were obtained from the closest air quality monitoring station. Linear mixed-effect model was applied to explore the associations between air pollutants and lung function, inflammation and oxidative stress. We observed higher PM2.5 exposure was associated with decrement in lung function and increment in CRP and MDA. Each 10 µg/m3 increase in PM2.5 (lag 2 day) is associated with a 17.06 ml (95% CI: -31.53, -2.58) decrease in FEV1, 46.34 ml/s (95% CI: -76.41, -16.27) decrease in PEF and increments of 2.86% (95% CI: 1.47%, 4.27%) in CRP, 1.63% (95% CI: 0.14%, 3.14%) in MDA respectively. However, there is no significant association between ozone exposure and health indicators. The study suggested that short-term exposure to PM2.5 may decrease lung function and induce inflammation and oxidative stress in healthy adults, but there is no association between O3 and each outcome.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Pulmón , Ozono , Material Particulado , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/efectos adversos , Proteína C-Reactiva/metabolismo , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Humanos , Inflamación/inducido químicamente , Pulmón/metabolismo , Pulmón/patología , Estrés Oxidativo , Ozono/toxicidad , Material Particulado/análisis , Material Particulado/toxicidad , Adulto Joven
13.
Chemosphere ; 308(Pt 1): 136241, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36041521

RESUMEN

Numerous studies have shown that air pollution seems to be able to cause many diseases. Considering the possible mechanism of action and the same growth trend, the present study is designed to examine whether and how air pollutants, especially ozone (O3) exposure, are associated with the incidence of gestational diabetes mellitus (GDM). By a retrospective cohort, we analyzed the records of 45439 pregnant women from 2013 to 2018 and matched them to maternal exposure to O3. We found that the increased odds of GDM is associated with increased O3 concentrations from the 1st month before pregnancy to the 3rd month during pregnancy. Specially, the odds ratios (ORs) of these associations were largest in the 1st month before pregnancy, suggesting that the effect of O3 pollution on GDM occurred in pre-pregnancy period. Moreover, the exposure-response plot in the 1st month before pregnancy showed that the odds of GDM increased with the increasing concentration of O3. Our findings provide the evidence that O3 exposure in both pre-pregnancy and pregnancy period elevates the odds of GDM, suggesting that more intensive air pollution controls are needed to improve the health of pregnant women and their offspring.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Diabetes Gestacional , Ozono , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Diabetes Gestacional/inducido químicamente , Diabetes Gestacional/epidemiología , Femenino , Humanos , Exposición Materna/efectos adversos , Ozono/efectos adversos , Ozono/análisis , Material Particulado/análisis , Embarazo , Estudios Retrospectivos
14.
J Environ Manage ; 319: 115741, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35841777

RESUMEN

Face masks play a crucial protective role in preventing the spread of coronavirus disease during the COVID-19 pandemic, but the improper disposal of used face masks also causes an emerging environmental problem, such as microplastic contamination. Here, the aim was to evaluate the improper disposal of used face masks and, subsequently, the potential contribution to microplastic contamination in urban rivers. First, we investigated the occurrence of discarded face masks in Qing River through continuously one-month collection on-site, and the disposable masks with a density of (8.28 ± 4.21) × 10-5 items/m2 with varying degrees of wear and tear were found. Next, the microfibers shedding from two popular types of new disposable masks were tested. The results showed that 50.33 ± 18.50 items/mask of microfibers, ranging from 301 µm to 467 µm in size, were released from the disposal face mask after immersion in ultrapure water for 24-h. It was significantly higher than the KN95 respirator of 31.33 ± 0.57 items/mask, ranging from 273 µm to 441 µm. Besides C and O elements only found in new face masks, some potentially toxic elements were also detected on the surface of discarded face masks, indicating that various environmental contaminations are easy to adsorb on the surface of discarded face masks. The results implied that these discarded face masks in an aquatic environment are emerging sources of microfibers and could act as transport vectors for contaminants, which would aggravate the present microplastic contamination. In conclusion, these findings were expected to raise public awareness of the proper disposal of used face masks to prevent microplastic contamination and the spread of COVID-19 in the environment.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Humanos , Máscaras , Microplásticos , Pandemias/prevención & control , Plásticos , Ríos , SARS-CoV-2
15.
Environ Sci Technol ; 56(21): 15167-15178, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35862635

RESUMEN

Dissemination of antibiotic resistance genes (ARGs) through natural transformation is facilitated by factors that stabilize extracellular DNA (eDNA) and that induce reactive oxygen species (ROS) that permeabilize receptor cells and upregulate transformation competence genes. In this study, we demonstrate that Deinococcus radiodurans can mitigate this ARG dissemination pathway by removing both eDNA and ROS that make recipient cells more vulnerable to transformation. We used plasmid RP4 as source of extracellular ARGs (tetA, aphA, and blaTEM-2) and the opportunistic pathogen Enterococcus faecalis as receptor. The presence of D. radiodurans significantly reduced the transformation frequency from 2.5 ± 0.7 × 10-6 to 7.4 ± 1.4 × 10-7 (p < 0.05). Based on quantification of intracellular ROS accumulation and superoxide dismutase (SOD) activity, and quantitative polymerase chain reaction (qPCR) and transcriptomic analyses, we propose two mechanisms by which D. radiodurans mitigates E. faecalis transformation by ARGs: (a) residual antibiotics induce D. radiodurans to synthesize liposoluble carotenoids that scavenge ROS and thus mitigate the susceptibility of E. faecalis for eDNA uptake, and (b) eDNA induces D. radiodurans to synthesize extracellular nucleases that degrade eARGs. This mechanistic insight informs biological strategies (including bioaugmentation) to curtail the spread of ARGs through transformation.


Asunto(s)
Antibacterianos , Enterococcus faecalis , Antibacterianos/farmacología , Enterococcus faecalis/genética , Especies Reactivas de Oxígeno , Farmacorresistencia Microbiana/genética , Bacterias/genética , Carotenoides , ADN
16.
Chemosphere ; 298: 134296, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35301995

RESUMEN

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer and has been identified as a male prenatal reproductive toxicant. A high fat diet (HFD) has also been suggested as another potential disruptor of male reproductive function. Despite this potential synergism between DEHP exposure and HFD, little is known about the concomitant effects of prenatal DEHP and a subsequent HFD exposure on male offspring reproductive injury. Here we established a mouse model of prenatal exposure to DEHP (0.2 mg/kg/day) to assess the testicular development and spermatogenesis in offspring subjected to obesogenic diet during the pubertal period. Gross phenotype, hormone profiles and the testicular metabolome were analyzed to determine the underlying mechanism. We found that prenatal exposure to low-dose DEHP resulted in decreased sperm density, decreased testosterone (T) levels, increased luteinizing hormone (LH) levels and testicular germ cell apoptosis. Furthermore, these injury phenotypes were aggravated by pubertal HFD treatment. Testicular riboflavin and biotin metabolites were enriched implying their roles in contributing HFD to exacerbate offspring spermatogenesis disorders due to prenatal low-dose DEHP exposure. Our findings suggest that pubertal HFD exacerbates reproductive dysfunction associated with prenatal exposure to low-dose DEHP in male adult offspring.


Asunto(s)
Dietilhexil Ftalato , Efectos Tardíos de la Exposición Prenatal , Animales , Dieta Alta en Grasa/efectos adversos , Dietilhexil Ftalato/metabolismo , Femenino , Humanos , Masculino , Ratones , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Espermatogénesis , Testículo
17.
Int J Hyg Environ Health ; 240: 113904, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34915280

RESUMEN

BACKGROUND: Existing evidence suggests that perfluoroalkyl and polyfluoroalkyl substances (PFASs) exposure might contribute to the incidence of gestational diabetes mellitus (GDM). This study aimed to perform a meta-analysis to identify the association between PFAS and the risk of GDM. METHODS: We systematically searched PubMed, Ovid, Cochrane Library, and Web of Science databases for appropriate articles about the association between PFASs exposure and the risk of GDM before September 28, 2020. Odds ratios (OR) with 95% confidence intervals (CIs) were summarized by Stata 16.0 through fixed effect models according to heterogeneity. We also carried out subgroup analyses by geographic location, blood sampling time of subjects, method of chemical analysis, study design, sample size, and sampling year. In addition, a sensitivity analysis was conducted to explore the robustness of the results. RESULTS: A total of eight studies involving 5654 pregnant women were included in the meta-analysis. Perfluorooctanoic acid (PFOA) exposure was positively and significantly associated with the risk of GDM (OR = 1.27, 95% CI: 1.02-1.59). Exposure to other types of PFASs such as perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA) was not statistically significantly associated with the risk of GDM with the pooled effect estimates of 0.97 (95% CI: 0.86-1.09), 1.03 (95% CI: 0.86-1.24), and 0.80 (95% CI: 0.55-1.16) respectively. CONCLUSION: We conducted a meta-analysis to investigate the association between PFASs exposure and GDM and found that PFOA concentration was significantly associated with a higher risk of GDM, which is of great significance for the prevention and control of GDM in public health. Further studies are needed in order to establish causality and clarify the potential mechanism.


Asunto(s)
Ácidos Alcanesulfónicos , Diabetes Gestacional , Contaminantes Ambientales , Fluorocarburos , Estudios de Cohortes , Diabetes Gestacional/epidemiología , Femenino , Humanos , Oportunidad Relativa , Embarazo
18.
Huan Jing Ke Xue ; 42(11): 5364-5374, 2021 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-34708975

RESUMEN

To investigate the impact of megacities on the chemistry of surface waters, monthly sampling and monitoring were conducted in the Chengdu section of the Minjiang and Tuojiang River basin, corresponding to the upper reaches of the Yangtze River since the spring of 2019, including the influent and effluent water samples from 57 sewage treatment plants in Chengdu. All the samples were analyzed for major ions and other water chemistry parameters, and compared with the historical data of the Minjiang and Tuojiang River. The results showed that the Chengdu surface water still presented a natural chemistry with medium-low total dissolved solids(TDS), and calcium bicarbonate chemistry type, which is the natural consequence of the weathering of carbonate rocks in the basin effected by the weathering of silicates and evaporites. The natural water chemistry of the surface waters in Chengdu presented monthly variation, i.e.,the concentration of major ions and TDS was higher in the dry season compared to the wet season, reflecting the variations of point source. Spatially, the concentration of major ions and TDS downstream of the city was higher than those in the upper reaches, and the concentration in the tributary was higher than that in the mainstream, which may reflect urban influence. Further analyses, such as simulation calculations, indicated that urban activities were the major driving factor for the chemistry change in the surface waters in Chengdu, which is evidenced by the significant contribution of the sewage discharge to the elevated Cl- and Na+ and the ratio of hardness/alkalinity>1 from anthropogenic acid gas emissions. A comparison with the water chemistry of the Minjiang and Tuojiang River in the 1960s indicated that, the current Cl-/Na+ ratio has significantly increased, which has been evidenced by a salinization trend. As a megacity nearest to the source of the Yangtze River, the impact of Chengdu on the natural water chemistry of the Yangtze River system and its environmental effects deserves more attention.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , Carbonatos/análisis , Ríos , Agua , Contaminantes Químicos del Agua/análisis
19.
Sci Total Environ ; 789: 148027, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-34323846

RESUMEN

Microplastics are a growing concern globally due to their small size and easy ingestion by terrestrial and aquatic organisms, resulting in potential adverse impacts on wildlife. However, current data regarding microplastics in wild organisms in different trophic levels is limited. This study investigated microplastic characteristics, including their abundance, size, shape and polymer type, in estuarine invertebrates and vertebrates. Resultantly, polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) were the predominant microplastics found, as confirmed by a Fourier transform infrared spectrometer (FT-IR). An average microplastic abundance of 0.83 ± 0.99 to 3.87 ± 2.18 items/individual was detected across all species, including sandworm, mollusks, crustacean and fish, but they were not found in all individuals. Microplastics ranged from 52 µm to 5392 µm in size, and the shapes were consisted of fiber, fragment, and pellet. Moreover, the detection ratio (91.95%) and abundance (3.34 ± 2.17 items/individual) of microplastics in fish were significantly higher than in sandworm (42.86%, 0.88 ± 1.04 items/individual), mollusks (66.97%, 1.42 ± 1.41 items/individual) and crustaceans (66.66%, 1.33 ± 1.32 items/individual) (p < 0.05). Furthermore, a positive relationship was identified between microplastic abundance and the trophic level of organisms. These findings imply that microplastics might transfer along the food chain and accumulate at organisms in higher trophic levels.

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