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World Journal of Gastroenterology Oct 2005To analyze occupational health hazards exposure to doses lower than the Chinese occupational health standard in a selected VC polymerization plant in China, and also to...
AIM
To analyze occupational health hazards exposure to doses lower than the Chinese occupational health standard in a selected VC polymerization plant in China, and also to elucidate the relationship between genetic polymorphisms and genetic susceptibility on liver lesions of workers exposed to vinyl chloride monomer(VCM).
METHODS
In order to explore the mechanism of VCM-related health effects, we used a case-control design to investigate the association between the genetic polymorphisms of metabolic enzymes and liver lesions in workers occupationally exposed to VCM. Genotypes of CYP2E1, GSTT1, GSTM1, ALDH2 and ADH2 were identified using PCR and PCR-RFLP.
RESULTS
Even when the concentration of VCM was lower than the current Chinese occupational health standard, neurasthenia, pharyngeal irritation, liver ultrasonography abnormalities and hemoglobin disorders were significantly higher in exposure subjects compared to non-exposure subjects, and the relative risks (RR and 95% CI) were 1.74 (1.06-2.85), 1.97 (1.56-2.48), 10.69 (4.38-26.12), and 2.07 (1.20-3.57). CYP2E1 c1c2/c2c2 genotype was significantly associated with liver damages (OR 3.29, 95% CI 1.51-7.20, P<0.01).
CONCLUSION
The incidences of neurasthenia and liver ultrasonography abnormalities significantly increase when the cumulative exposure dose increases. The genotypes of metabolic enzymes (CYP2E1 c1c2/c2c2, null GSTT1 and ADH2 1-1) play important roles in VCM metabolism. Polymorphisms of CYP 2E1, GSTT1 and ADH2 may be a major reason of genetic susceptibility in VCM-induced hepatic damage.
Topics: Case-Control Studies; Chemical Industry; China; Enzymes; Genetic Predisposition to Disease; Genotype; Humans; Inhalation Exposure; Liver; Occupational Exposure; Polymorphism, Genetic; Regression Analysis; Statistics as Topic; Vinyl Chloride
PubMed: 16270392
DOI: 10.3748/wjg.v11.i37.5821 -
Bean Dreg-Hydrocalumite Composite as a Highly Efficient Thermal Stabilizer for Poly(vinyl chloride).ACS Omega Jun 2022Bean dreg (BD)-hydrocalumite composites were prepared by a hydrothermal method with BD, Ca(OH), Al(OH), and NaCO as raw materials. The samples were characterized by...
Bean dreg (BD)-hydrocalumite composites were prepared by a hydrothermal method with BD, Ca(OH), Al(OH), and NaCO as raw materials. The samples were characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and N physical adsorption-desorption. Their properties as a thermal stabilizer for poly(vinyl chloride) were tested using a torque rheometer and static thermal aging method. Compared with traditional hydrocalumite, the crystal size of the BD-hydrocalumite composite was relatively small, which made it exhibit good dispersion and better thermal stability for poly(vinyl chloride). In addition, the effects of preparation conditions on the properties of BD-hydrocalumite as a heat stabilizer were also investigated. Under the conditions of [Ca(OH)/Al(OH)/NaCO] = 4.4:2:1, a BD dosage of 5%, a crystallization temperature of 90 °C, and 19 h, the prepared BD-hydrocalumite showed the best performance, and the dynamic thermal stability time of poly(vinyl chloride) reached 2149 s.
PubMed: 35694515
DOI: 10.1021/acsomega.2c01835 -
International Journal of Molecular... May 2021High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period....
BACKGROUND
High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period. Although VC is genotoxic, a more comprehensive mode of action has not been determined and diagnostic biomarkers have not been established. The purpose of this study is to address these knowledge gaps through plasma metabolomics.
METHODS
Plasma samples from polyvinyl chloride polymerization workers who developed hemangiosarcoma (cases, = 15) and VC exposure-matched controls ( = 17) underwent metabolomic analysis. Random forest and bioinformatic analyses were performed.
RESULTS
Cases and controls had similar demographics and routine liver biochemistries. Mass spectroscopy identified 606 known metabolites. Random forest analysis had an 82% predictive accuracy for group classification. 60 metabolites were significantly increased and 44 were decreased vs. controls. Taurocholate, bradykinin and fibrin degradation product 2 were up-regulated by greater than 80-fold. The naturally occurring anti-angiogenic phenol, 4-hydroxybenzyl alcohol, was down-regulated 5-fold. Top affected ontologies involved: (i) metabolism of bile acids, taurine, cholesterol, fatty acids and amino acids; (ii) inflammation and oxidative stress; and (iii) nicotinic cholinergic signaling.
CONCLUSIONS
The plasma metabolome was differentially regulated in polyvinyl chloride workers who developed hepatic hemangiosarcoma. Ontologies potentially involved in hemangiosarcoma pathogenesis and candidate biomarkers were identified.
Topics: Biomarkers; Case-Control Studies; Hemangiosarcoma; Humans; Liver Neoplasms; Male; Metabolome; Middle Aged; Occupational Diseases; Occupational Exposure; Polyvinyl Chloride; United States
PubMed: 34065028
DOI: 10.3390/ijms22105093 -
Environmental Science and Pollution... Jul 2012Chlorinated ethanes and ethenes are among the most frequently detected organic pollutants of water. Their physicochemical properties are such that they can contaminate... (Review)
Review
INTRODUCTION
Chlorinated ethanes and ethenes are among the most frequently detected organic pollutants of water. Their physicochemical properties are such that they can contaminate aquifers for decades. In favourable conditions, they can undergo degradation. In anaerobic conditions, chlorinated solvents can undergo reductive dechlorination.
DEGRADATION PATHWAYS
Abiotic dechlorination is usually slower than microbial but abiotic dechlorination is usually complete. In favourable conditions, abiotic reactions bring significant contribution to natural attenuation processes. Abiotic agents that may enhance the reductive dechlorination of chlorinated ethanes and ethenes are zero-valent metals, sulphide minerals or green rusts.
OXIDATION
At some sites, permanganate and Fenton's reagent can be used as remediation tool for oxidation of chlorinated ethanes and ethenes.
SUMMARY
Nanoscale iron or bimetallic particles, due to high efficiency in degradation of chlorinated ethanes and ethenes, have gained much interest. They allow for rapid degradation of chlorinated ethanes and ethenes in water phase, but they also give benefit of treating dense non-aqueous phase liquid.
Topics: Ethyl Chloride; Iron; Metal Nanoparticles; Palladium; Porphyrins; Vinyl Chloride; Water; Water Pollutants, Chemical; Zinc
PubMed: 22293908
DOI: 10.1007/s11356-012-0764-9 -
Toxicological Research Oct 2022Vinyl chloride is a colorless gas with a pleasant odor capable of entering the body through oral or inhalation routes. Extensive studies on this compound indicated that...
Vinyl chloride is a colorless gas with a pleasant odor capable of entering the body through oral or inhalation routes. Extensive studies on this compound indicated that it is a carcinogen, and Vinyl chloride exposure can result in a specific type of cancer in vinyl chloride workers. Whereas hemoglobin plays a vital role in oxygen transfer throughout the body, in a molecular aspect, the effect of vinyl chloride on human hemoglobin has not been studied. Furthermore, selenium as an antioxidant is a vital factor for the health of humans and animals. Then this research investigated the effect of the antioxidant capability of selenium at the same concentrations in blood on the interaction between vinyl chloride and hemoglobin. UV-visible, Fourier-transform infrared, chemiluminescence, and fluorescence spectroscopies were employed. The results indicated the destruction of hemoglobin structure in different concentrations of vinyl chloride. At the same time, the antioxidant effect of selenium inhibited the destructive impact of vinyl chloride on hemoglobin structure.
PubMed: 36277367
DOI: 10.1007/s43188-022-00137-1 -
ACS Omega May 2023Due to their high anion exchange and memory effect, the layered double hydroxides (LHDs) have wide applications for some areas. In this work, an efficient and green...
Due to their high anion exchange and memory effect, the layered double hydroxides (LHDs) have wide applications for some areas. In this work, an efficient and green recycling route for layered double hydroxide based adsorbents is proposed specifically for application as a poly(vinyl chloride) (PVC) heat stabilizer without requiring secondary calcination. Conventional magnesium-aluminum hydrotalcite was synthesized using the hydrothermal method followed by removal of carbonate anion (CO) between LDH layers by calcination. The adsorption of perchlorate anion (ClO) by the memory effect of calcined LDHs with and without ultrasound assistance was compared. Using ultrasound assistance, the maximum adsorption capacity of the adsorbents (291.89 mg/g) was increased, and the adsorption process was fitted using the kinetic Elovich rate equation ( = 0.992) and Langmuir adsorption model ( = 0.996). This material was characterized using XRD, FT-IR, EDS, and TGA which demonstrated that ClO was intercalated into the hydrotalcite layer successfully. The recycled adsorbents were used to augment a commercial calcium-zinc-based PVC stabilizer package applied in a epoxidized soybean oil plasticized cast sheet which is based on an emulsion type PVC homopolymer resin. Use of perchlorate intercalated LDH augmentation yielded significant improvement to static heat resistance as indicated by the degree of discoloration with a life extension of approximately 60 min. The improved stability was corroborated by evaluation of HCl gas evolved during thermal degradation using conductivity change curves and the Congo red test.
PubMed: 37251198
DOI: 10.1021/acsomega.3c00176 -
Polymers Mar 2022The plasticizers used in this study were synthesized from renewable raw materials using succinic acid, oleic acid, and propylene glycol. Four environmentally friendly...
The plasticizers used in this study were synthesized from renewable raw materials using succinic acid, oleic acid, and propylene glycol. Four environmentally friendly plasticizer samples were obtained; their chemical structures and compositions were confirmed by gas chromatography (GC) and infrared spectroscopy (FT-IR) analyses, and their physicochemical properties and thermal stability (TGA analysis) were investigated. The obtained ester mixtures were used as poly(vinyl chloride) (PVC) plasticizers and their plasticization efficiency was determined in comparison to traditional, commercially available phthalate plasticizers, such as DEHP (di(2-ethylhexyl phthalate) and DINP (diisononyl phthalate). Mechanical properties and migration resistance were determined for soft PVC with the use of three concentrations of plasticizers (40 PHR, 50 PHR, and 60 PHR). It was observed that the obtained plasticizers exhibited the same plasticization efficiency and were characterized with good mechanical and physical properties in comparison to commercial plasticizers. The tensile strength was approx. 19 MPa, while the elongation at break was approx. 250% for all tested plasticizers at a concentration of 50 PHR. Furthermore, plasticizer migration studies showed that the synthesized plasticizers had excellent resistance to plasticizer leaching. The best migration test result obtained was 70% lower than that for DEHP or DINP. The ester mixture that was found to be the most favorable plasticizer was characterized by good thermal and thermo-oxidative stability (5% weight loss temperature: 227.8 °C in air and 261.1 °C in nitrogen). The results of the research clearly indicate that the synthesized esters can provide a green alternative to toxic phthalate plasticizers.
PubMed: 35406169
DOI: 10.3390/polym14071295 -
Molecules (Basel, Switzerland) Nov 2022In this work, a method to increase the dispersion of graphene (GN) in the matrix of rigid poly(vinyl chloride) (PVC) by using a natural plant extract from L. (CE) is...
In this work, a method to increase the dispersion of graphene (GN) in the matrix of rigid poly(vinyl chloride) (PVC) by using a natural plant extract from L. (CE) is proposed. Currently, despite the increasing number of reports on the improvement of GN dispersion in PVC blends, still there is a need to find environmentally friendly and economical dispersion stabilizers. We proposed a stabilizer that can be easily obtained from a plant offering thermal stability and high effectiveness. PVC/GN nanocomposites stabilized with the proposed extract were investigated by SEM, AFM (structure), TGA, and Congo red test (thermal properties). Additionally, static and dynamic mechanical properties and electrical resistivity were measured. The use of CE as a graphene dispersant improved its dispersion in the PVC matrix, influenced tensile properties, increased the storage modulus and glass transition temperature, and extended the thermal stability time of nanocomposites. In this work, a CE extract is proposed as an efficient eco-friendly additive for the production of nanocomposites with an improved homogeneity of a nanofiller in the matrix and promising characteristics.
Topics: Graphite; Curcuma; Rhizome; Vinyl Chloride; Polyvinyl Chloride; Nanocomposites; Plant Extracts
PubMed: 36432182
DOI: 10.3390/molecules27228081 -
RSC Advances May 2018Herein, we report the incorporation of a 10 μm thick reduced graphene oxide (RGO) barrier layer in a plasticized poly(vinyl chloride) (PVC) film as the main constituent...
Herein, we report the incorporation of a 10 μm thick reduced graphene oxide (RGO) barrier layer in a plasticized poly(vinyl chloride) (PVC) film as the main constituent in ion-selective membranes used in potentiometric solid-contact ion-selective electrodes (SCISE). Fourier transform infrared attenuated total reflection (FTIR-ATR) and oxygen transmission rate (OTR) measurements showed that the embedded RGO barrier efficiently impedes the diffusion of liquid water, carbon dioxide and oxygen (O) through the 400 μm thick PVC film, which causes potential instability and irreproducibility of the SCISEs. The measurements revealed that the RGO layer completely blocks the carbon dioxide diffusion, while it fully blocks the water diffusion for 16 h and reduced the OTR by 85% on average. The μm-thick RGO films used in this study were easier to handle and incorporate into host polymers, and form more efficient and robust barriers compared to the mono-, few- and multilayer graphene commonly applied as barrier layers for liquids and gases. We also demonstrated that the FTIR-ATR technique employed in the permeability measurements is a versatile and very sensitive technique for studying the diffusion of small amounts of water and carbon dioxide through graphene-based thin films.
PubMed: 35542063
DOI: 10.1039/c8ra03080d -
Environmental Health Perspectives Oct 1981The contributions of several recent reports to the definition of pulmonary effects of PVC dust inhalation are reviewed. Granulomatous reaction, with inclusion of PVC...
The contributions of several recent reports to the definition of pulmonary effects of PVC dust inhalation are reviewed. Granulomatous reaction, with inclusion of PVC particles in macrophages and histocytes, and associated interstitial pulmonary fibrosis have been found to lead to exertional dyspnoea, diffuse micronodular chest radiographic opacities and restrictive pulmonary dysfunction. The effects of vinyl chloride (VC) monomer (gas) on proteins and the immunologic mechanisms triggered by the altered protein are possible mechanisms for the development in some cases of interstitial pulmonary fibrosis secondary to VC exposure. Vinyl chloride, a confirmed carcinogen, has been associated with, among other malignant tumors, a significant increase in the incidence of lung cancer. The magnitude of this effect has not yet been completely evaluated.
Topics: Dust; Humans; Lung Neoplasms; Occupational Diseases; Polyvinyl Chloride; Polyvinyls; Pulmonary Fibrosis; Vinyl Chloride; Vinyl Compounds
PubMed: 7333234
DOI: 10.1289/ehp.8141167