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Chemosphere Jul 2024Development of efficient catalysts for non-thermal plasma (NTP) assisted catalysis to mitigate the formation of harmful by-products is a significant challenge in the...
Development of efficient catalysts for non-thermal plasma (NTP) assisted catalysis to mitigate the formation of harmful by-products is a significant challenge in the degradation of chlorinated volatile organic compounds (Cl-VOCs). In this study, catalytically active Pt nanoparticles supported on non-porous SiO2 and silicalite-1 zeolites (S1) with different pore structure were comparatively investigated for catalytic chlorobenzene degradation under NTP condition. It was shown that the pore structure could significantly impact the metal size and metal dispersion rate. Pt supported on modified S1 hierarchical meso-micro-porous silicalite-1 (Pt/D-S1) exhibited the smallest particle size (∼6.19 nm) and the highest dispersion rate (∼1.87). Additionally, Pt/D-S1 demonstrated superior catalytic performance compared to the other catalysts, achieving the highest chlorobenzene conversion and COx selectivity at about 80% and 75%, respectively. Furthermore, the pore structure also affected the formation of by-products according to the findings from GC-MS analysis. Pt/SiO generated a total of 18 different species of organic compounds, whereas only 12 species of organic by-products were identified in the Pt/D-S1 system (e.g. polychlorinated compounds like 3,4 dichlorophenol were exclusively identified in Pt/SiO). Moreover, dioxin-like polychlorinated biphenyl and other chlorinated organic compounds, which have potential to form highly toxic dioxins, were detected in the catalysts. HRGC-HRMS confirmed and quantified the 17 different dioxin/furans formed on Pt/SiO (25,100 ng TEQ kg), Pt/S1 (515 ng TEQ kg) and Pt/D-S1 (367 ng TEQ kg). The correlation between synthesis-structure-performance in this study provides insights into the design of catalysts for deep oxidation of Cl-VOCs in NTP system.
Topics: Chlorobenzenes; Catalysis; Platinum; Silicon Dioxide; Polychlorinated Dibenzodioxins; Plasma Gases; Zeolites; Volatile Organic Compounds; Metal Nanoparticles; Benzofurans
PubMed: 38734247
DOI: 10.1016/j.chemosphere.2024.142294 -
Ecotoxicology and Environmental Safety Jun 20243,3',4,4',5-Pentachlorobiphenyl (PCB126) is the most toxic congener of dioxin-like polychlorinated biphenyls (DL PCBs), while nanoplastics (NPs) have recently emerged as...
3,3',4,4',5-Pentachlorobiphenyl (PCB126) is the most toxic congener of dioxin-like polychlorinated biphenyls (DL PCBs), while nanoplastics (NPs) have recently emerged as significant marine pollutants, both posing threats to aquatic organisms and human health. They coexist in the environment, but their comprehensive toxicological effects remain unclear. In this study, zebrafish embryos were simultaneously exposed to PCB126 and 80-nanometer nanoplastyrene (NPS). Researchers utilized fluorescence microscopy, qPCR, histopathological examination, and transcriptomic sequencing to investigate the developmental toxicity of different concentrations of PCB126 and NPS individually or in combination on zebrafish embryos and larvae. Results indicate that the chorion significantly impedes the accumulation of NPS (p < 0.05). It is noteworthy that this barrier effect diminishes upon simultaneous exposure to PCB126. In this experiment, the semi-lethal concentration of PCB126 for larvae was determined to be 6.33 μg/L. Exposure to PCB126 induces various deformities, primarily mediated through the aryl hydrocarbon receptor (AHR). Similarly, exposure to NPS also activates AHR, leading to developmental impairments. Furthermore, transcriptomic sequencing revealed similar effects of PCB126 and NPS on the gene expression trends in zebrafish larvae, but combined exposure to both exacerbates the risk of cancer and induces more severe cardiac toxicity. At this level, co-exposure to PCB126 and NPS adversely affects the development of zebrafish larvae. This study contributes to a deeper understanding of the in vivo accumulation of DL polychlorinated biphenyls and microplastics in actual aquatic environments and their impact on fish development.
Topics: Animals; Zebrafish; Polychlorinated Biphenyls; Larva; Water Pollutants, Chemical; Polystyrenes; Embryo, Nonmammalian; Microplastics; Nanoparticles
PubMed: 38718726
DOI: 10.1016/j.ecoenv.2024.116419 -
Environment International May 2024Exposure to persistent organic pollutants (POPs), such as dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs), has historically been linked to...
Exposure to persistent organic pollutants (POPs), such as dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs), has historically been linked to population collapses in wildlife. Despite international regulations, these legacy chemicals are still currently detected in women of reproductive age, and their levels correlate with reduced ovarian reserve, longer time-to-pregnancy, and higher risk of infertility. However, the specific modes of action underlying these associations remain unclear. Here, we examined the effects of five commonly occurring POPs - hexachlorobenzene (HCB), p,p'-dichlorodiphenyldichloroethylene (DDE), 2,3,3',4,4',5-hexachlorobiphenyl (PCB156), 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB180), perfluorooctane sulfonate (PFOS) - and their mixture on human ovaries in vitro. We exposed human ovarian cancer cell lines COV434, KGN, and PA1 as well as primary ovarian cells for 24 h, and ovarian tissue containing unilaminar follicles for 6 days. RNA-sequencing of samples exposed to concentrations covering epidemiologically relevant levels revealed significant gene expression changes related to central energy metabolism in the exposed cells, indicating glycolysis, oxidative phosphorylation, fatty acid metabolism, and reactive oxygen species as potential shared targets of POP exposures in ovarian cells. Alpha-enolase (ENO1), lactate dehydrogenase A (LDHA), cytochrome C oxidase subunit 4I1 (COX4I1), ATP synthase F1 subunit alpha (ATP5A), and glutathione peroxidase 4 (GPX4) were validated as targets through qPCR in additional cell culture experiments in KGN. In ovarian tissue cultures, we observed significant effects of exposure on follicle growth and atresia as well as protein expression. All POP exposures, except PCB180, decreased unilaminar follicle proportion and increased follicle atresia. Immunostaining confirmed altered expression of LDHA, ATP5A, and GPX4 in the exposed tissues. Moreover, POP exposures modified ATP production in KGN and tissue culture. In conclusion, our results demonstrate the disruption of cellular energy metabolism as a novel mode of action underlying POP-mediated interference of follicle growth in human ovaries.
Topics: Humans; Female; Ovary; Persistent Organic Pollutants; Energy Metabolism; Fluorocarbons; Homeostasis; Cell Line, Tumor; Polychlorinated Biphenyls; Dichlorodiphenyl Dichloroethylene; Alkanesulfonic Acids; Hexachlorobenzene
PubMed: 38701644
DOI: 10.1016/j.envint.2024.108710 -
Scientific Reports Apr 2024Our understanding of the environmental and occupational health implications of pollutants emitted in steel production is still lacking, despite the considerable amount...
Our understanding of the environmental and occupational health implications of pollutants emitted in steel production is still lacking, despite the considerable amount of research devoted to this topic. Given the significance of steel recycling and the need to reduce greenhouse gas emissions, many steel factories are adopting electric arc furnace (EAF) technology. The use of a technological system designed for the capture of pollutants emitted through EAF steel production is highly ecological because of its utilization of iron scrap and low investment cost. Despite this, the main issue with the EAF is the environmental impact it poses, specifically the release of pollutants into the air, such as dust and organic substances, chlorinated dioxins and furans, dioxin-like polychlorinated biphenyls and brominated dioxins and furans. As a result, workers in this field have a considerable rate of morbidity. The main challenge for EAFs is to optimize the capture of powders produced during the techno-logical process, both from the EAF and the workplace. A state-of-the art solution for managing pollutants in modern steel manufacturing is highlighted in this paper, featuring a method used in Romania that employs the Best Available Techniques (BAT) reference document for iron and steel production to directly collect pollutants from the EAF. The system included a cylindrical fitting, a heat exchanger to cool the gases and a hood to collect contaminants. In comparison to other ventilation options, this equipment boasts lower investment and lower operational costs because of its effective and minimal air flow. Through the use of cutting-edge technology and progressive strategies, we can move closer toward our objective of a workplace free from injuries in the steel industry.
PubMed: 38688973
DOI: 10.1038/s41598-024-60817-w -
International Journal of Molecular... Apr 2024We aimed to explore the relationship of adipose tissue concentrations of some persistent organic pollutants (POPs) with the risk of endometriosis and the endometriotic...
We aimed to explore the relationship of adipose tissue concentrations of some persistent organic pollutants (POPs) with the risk of endometriosis and the endometriotic tissue expression profile of genes related to the endometriosis-related epithelial-mesenchymal transition (EMT) process. This case-control study enrolled 109 women (34 cases and 75 controls) between January 2018 and March 2020. Adipose tissue samples and endometriotic tissues were intraoperatively collected to determine concentrations of nine POPs and the gene expression profiles of 36 EMT-related genes, respectively. Associations of POPs with endometriosis risk were explored with multivariate logistic regression, while the relationship between exposure and gene expression profiles was assessed through Spearman correlation or Mann-Whitney U tests. After adjustment, increased endometriosis risk was associated with -DDT, PCB-180, and ΣPCBs. POP exposure was also associated with reduced gene expression levels of the CLDN7 epithelial marker and increased levels of the ITGB2 mesenchymal marker and a variety of EMT promoters (HMGA1, HOXA10, FOXM1, DKK1, CCR1, TNFRSF1B, RRM2, ANG, ANGPT1, and ESR1). Our findings indicate that exposure to POPs may increase the risk of endometriosis and might have a role in the endometriosis-related EMT development, contributing to the disease onset and progression. Further studies are warranted to corroborate these findings.
Topics: Endometriosis; Humans; Female; Epithelial-Mesenchymal Transition; Adult; Environmental Exposure; Case-Control Studies; Persistent Organic Pollutants; Adipose Tissue; Endometrium; Risk Factors
PubMed: 38674005
DOI: 10.3390/ijms25084420 -
Foods (Basel, Switzerland) Apr 2024The aim of this study was to evaluate contamination levels and the frequency of detection of organochlorine (OCPs) and organophosphate pesticides (OPPs), pyrethroids,...
The aim of this study was to evaluate contamination levels and the frequency of detection of organochlorine (OCPs) and organophosphate pesticides (OPPs), pyrethroids, carbamates and polychlorinated biphenyls (seven PCB congeners) in a total of 534 samples of cow's, sheep's and goat's milk and dairy products from Croatia. Concentrations above the limit of quantification (LOQ) were measured for fourteen OCPs, nine OPPs, six pyrethroids, one carbamate and PCBs with a total of 172 results, and no concentrations exceeded the maximal residue levels defined by the European Union. The mean concentrations of pesticides and the sum of seven PCBs were determined in the ranges 0.92-17.4 μg/kg and 1.38-2.74 μg/kg. Pesticides were quantified in 27% of samples, and seven PCBs were quantified in 5.23% of samples. Among the three pesticide groups, the highest numbers of quantified results were found for OCPs (12.1-20.8%). The highest frequencies of detection were found for the sum of 4,4'-dichlorodiphenyltrichloroethane and its isomers (DDTs), hexachlorobenzene and seven PCBs. The sum of seven PCBs was quantified within the range of 3.3-6.67% of samples per milk type and dairy products. Among the OPPs, the highest frequency of detection was found for chlorpyrifos in cow's milk. Based on the estimated daily intakes, chronic risk characterisation showed no risk for adults or ten-year-old children for the consumption of cow's milk and dairy products.
PubMed: 38672828
DOI: 10.3390/foods13081155 -
Environment International May 2024The blood levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been thoroughly investigated in Greek children from the Rhea birth cohort...
Systematic investigation of organochlorine pesticides and polychlorinated biphenyls blood levels in Greek children from the Rhea birth cohort suggests historical exposure to DDT and through diet to DDE.
The blood levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been thoroughly investigated in Greek children from the Rhea birth cohort study. This investigation aimed to assess exposure levels, explore their possible relationship with children's age and sex, and indicate potential sources of exposure. Exposure patterns and common sources of PCBs and OCPs were analyzed using bivariate and multivariate statistics. A total of 947 blood samples from study participants were analyzed for OCP and PCB exposure, with 375 samples collected at 4 years old, 239 at 6.5 years old, and 333 at 11 years old. Elevated levels of DDE were observed in 6.5-year-old children compared to corresponding levels in other European countries. Higher levels of DDE were found in 4-year-old children, with the lowest concentrations in the 11-year-old group. The DDT/DDE ratio was consistently less than 1 among all the examined subjects. These results indicate exposure to DDT and DDE both in utero and through breastfeeding and dietary intake. For the entire cohort population, the highest concentration was determined for PCB 28, followed by PCBs 138, 153, and 180. The sum of the six indicator PCBs implied low exposure levels for the majority of the cohort population. Spearman correlations revealed strong associations between PCBs and OCPs, while principal component analysis identified two different groupings of exposure. DDE exhibited a correlation with a series of PCBs (153, 156, 163, 180), indicating a combined OCP-PCB source, and an anticorrelation with others (52, 28, 101), implying a separate and competing source.
Topics: Humans; Polychlorinated Biphenyls; Child; Female; Greece; Hydrocarbons, Chlorinated; Male; Child, Preschool; Pesticides; DDT; Dichlorodiphenyl Dichloroethylene; Environmental Pollutants; Environmental Exposure; Birth Cohort; Cohort Studies; Diet
PubMed: 38669722
DOI: 10.1016/j.envint.2024.108686 -
Toxics Mar 2024Polychlorinated biphenyls (PCBs) are a group of colorless and odorless environmental pollutants with a wide range of toxic effects. Some PCBs, especially less...
Polychlorinated biphenyls (PCBs) are a group of colorless and odorless environmental pollutants with a wide range of toxic effects. Some PCBs, especially less chlorinated ones, will rapidly undergo phase I metabolism after entering the body, and hydroxylated polychlorinated biphenyls (OH-PCBs) are the main metabolites of PCBs. Intestinal flora α-glucosidase is a common carbohydrate-active enzyme which is ubiquitous in human intestinal flora. It can convert complex dietary polysaccharides into monosaccharides, assisting the body in degrading complex carbohydrates and providing energy for the survival and growth of bacterial flora. The present study aims to investigate the inhibition of the activity of intestinal flora α-glucosidase by OH-PCBs. 4-Nitrophenyl-α-D-glucopyranoside (PNPG) was used as a probe substrate for α-glucosidase, and in vitro incubation experiments were conducted to study the inhibition of 26 representative OH-PCBs on α-glucosidase. Preliminary screening of in vitro incubation was performed with 100 μM of OH-PCBs. The results showed that 26 OH-PCBs generally exhibited strong inhibition of α-glucosidase. The concentration-dependent inhibition and half inhibition concentrations (IC50s) of OH-PCBs on α-glucosidase were determined. 4'-OH-PCB 86 and 4'-OH-PCB 106 were chosen as representative OH-PCBs, and the inhibition kinetic parameters (Kis) of inhibitors for α-glucosidase were determined. The inhibition kinetic parameters (Kis) of 4'-OH-PCB 86 and 4'-OH-PCB 106 for α-glucosidase are 1.007 μM and 0.538 μM, respectively. The silico docking method was used to further analyze the interaction mechanism between OH-PCBs and α-glucosidase. All these results will help us to understand the risks of OH-PCB exposure from a new perspective.
PubMed: 38668460
DOI: 10.3390/toxics12040237 -
Environment & Health (Washington, D.C.) Apr 2024Halogenated natural products (HNPs) are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known. Therefore, several...
Halogenated natural products (HNPs) are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known. Therefore, several persistent and bioaccumulative HNP groups, together with man-made polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), were quantified in the blubber of nine sperm whales () stranded on the coast of the Mediterranean Sea in Italy. The naturally occurring polybrominated hexahydroxanthene derivatives (PBHDs; sum of TetraBHD and TriBHD) were the most prominent substance class with up to 77,000 ng/g blubber. The mean PBHD content (35,800 ng/g blubber) even exceeded the one of PCBs (28,400 ng/g blubber), although the region is known to be highly contaminated with man-made contaminants. Based on mean values, Q1 ∼ PBDEs > MeO-BDEs ∼ 2,2'-diMeO-BB 80 and several other HNPs followed with decreasing amounts. All blubber samples contained an abundant compound whose molecular formula (CHBrO) was verified using high-resolution mass spectrometry. The only plausible matching isomer was (2,4',9,9')-2,7-dibromo-4'-bromomethyl-1,1-dimethyl-2,3,4,4',9,9'-9,9'-hexahydro-1-xanthen-9-ol (OH-TriBHD), a hydroxylated secondary metabolite previously detected together with TriBHD and TetraBHD in a sponge known to be a natural producer of PBHDs. The estimated mean amount of the presumed OH-TriBHD was 3000 ng/g blubber, which is unexpectedly high for hydroxylated compounds in the lipids of marine mammals.
PubMed: 38660428
DOI: 10.1021/envhealth.3c00182 -
Environment & Health (Washington, D.C.) Apr 2024Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are persistent organic pollutants (POPs) that bioaccumulate in adipose tissue. We investigated the...
Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are persistent organic pollutants (POPs) that bioaccumulate in adipose tissue. We investigated the relationship between change in central adiposity and changes in circulating concentrations of POPs over a 12-year period during the midlife. Serum concentrations of 34 PCBs and 19 OCPs were measured at four time points (1999/2000, 2002/03, 2005/06, 2009/11) in a cohort of midlife women, the Study of Women's Health Across the Nation. Linear mixed models were used to test the association between a change in waist circumference and a change in serum POP concentrations. Sixty-five women contributed 181 PCB observations. Fifty-nine women contributed 151 OCP observations. After adjustment for covariates (study site, race and ethnicity, age at baseline, parity), a one-inch (2.54 cm) increase in the change in waist circumference between visits was associated with a 4.9% decrease in the change in serum concentration of PCB 194 (95% CI: -8.0%, -1.6%). No associations were observed for other PCB congeners or the presence of OCPs. An increase in the difference in waist circumference over time was not associated with a change in the difference in serum concentrations of PCBs and OCPs except for PCB 194, possibly due to the high lipophilicity.
PubMed: 38660427
DOI: 10.1021/envhealth.3c00159