Polyvinyl Chloride Products Research Articles

Exposure to phthalates affects calcium handling and intercellular connectivity of human stem cell-derived cardiomyocytes.

BackgroundThe pervasive nature of plastics has raised concerns about the impact of continuous exposure to plastic additives on human health. Of particular concern is the use of phthalates in the production of flexible polyvinyl chloride (PVC) products. Di-2-ethylhexyl-phthalate (DEHP) is a commonly used phthalate ester plasticizer that imparts flexibility and elasticity to PVC products. Recent epidemiological studies have reported correlations between urinary phthalate concentrations and cardiovascular disease, including an increased risk of high blood pressure and coronary risk. Yet, there is little direct evidence linking phthalate exposure to adverse effects in human cells, including cardiomyocytes.Methods and ResultsThe effect of DEHP on calcium handling was examined using monolayers of gCAMP3 human embryonic stem cell-derived cardiomyocytes, which contain an endogenous calcium sensor. Cardiomyocytes were exposed to DEHP (5 – 50 μg/mL), and calcium transients were recorded using a Zeiss confocal imaging system. DEHP exposure (24 – 72 hr) had a negative chronotropic and inotropic effect on cardiomyocytes, increased the minimum threshold voltage required for external pacing, and modified connexin-43 expression. Application of Wy-14,643 (100 μM), an agonist for the peroxisome proliferator-activated receptor alpha, did not replicate DEHP’s effects on calcium transient morphology or spontaneous beating rate.ConclusionsPhthalates can affect the normal physiology of human cardiomyocytes, including DEHP elicited perturbations in cardiac calcium handling and intercellular connectivity. Our findings call for additional studies to clarify the extent by which phthalate exposure can alter cardiac function, particularly in vulnerable patient populations who are at risk for high phthalate exposure.

Tribo-Aero-Electrostatic Separator for Ternary Mixtures of Granular Plastics

This paper presents a comprehensive study of an electrostatic separation device for the recycling of granular plastic materials from waste electrical and electronic equipment (WEEE). The peculiarity of this system is the association of two charging techniques: 1) fluidized bed (dynamic charger) and 2) sliding on inclined plates (static charger)—and two superposed separation units, in order to achieve the selective sorting of a granular mixture composed of three different species of insulating materials. The tests were performed on a mixture of high-density polyethylene (HDPE), polyvinyl chloride (PVC), and polycarbonate (PC). A set of tribocharging experiments was conducted for each material, so that to choose the nature of the walls of the static charger. The analysis of the purity of separated products was performed using an image processing program written in MATLAB. High-purity separation (85%, 95%, and 75% for the PVC, PC, and HDPE products, respectively) was obtained at a recovery rate beyond 80%.

The effects of phthalates on the ovary.

Phthalates are commonly used as plasticizers in the manufacturing of flexible polyvinyl chloride products. Large production volumes of phthalates and their widespread use in common consumer, medical, building, and personal care products lead to ubiquitous human exposure via oral ingestion, inhalation, and dermal contact. Recently, several phthalates have been classified as reproductive toxicants and endocrine-disrupting chemicals based on their ability to interfere with normal reproductive function and hormone signaling. Therefore, exposure to phthalates represents a public health concern. Currently, the effects of phthalates on male reproduction are better understood than the effects on female reproduction. This is of concern because women are often exposed to higher levels of phthalates than men through their extensive use of personal care and cosmetic products. In the female, a primary regulator of reproductive and endocrine function is the ovary. Specifically, the ovary is responsible for folliculogenesis, the proper maturation of gametes for fertilization, and steroidogenesis, and the synthesis of necessary sex steroid hormones. Any defect in the regulation of these processes can cause complications for reproductive and non-reproductive health. For instance, phthalate-induced defects in folliculogenesis and steroidogenesis can cause infertility, premature ovarian failure, and non-reproductive disorders. Presently, there is a paucity of knowledge on the effects of phthalates on normal ovarian function; however, recent work has established the ovary as a target of phthalate toxicity. This review summarizes what is currently known about the effects of phthalates on the ovary and the mechanisms by which phthalates exert ovarian toxicity, with a particular focus on the effects on folliculogenesis and steroidogenesis. Further, this review outlines future directions, including the necessity of examining the effects of phthalates at doses that mimic human exposure.

Synthesis of a novel phosphorus-containing plasticizer based on castor oil and its application for flame retardancy of polyvinyl chloride

A novel flame-retardant plasticizer based on castor oil (FRC) was synthesized, and its potential application for polyvinyl chloride (PVC) was evaluated through the study of torque during melt processing, thermogravimetric analysis (TGA), limiting oxygen index instrument, scanning electron microscope (SEM) and mechanical tests. The results suggested that the FRC has a plasticizing effect in blends with PVC. The addition of FRC resulted in reduction of processing torque, good compatibility, improvement in thermal stability and efficient flame retardant. Torque reduction was observed (33.6%), indicating the reduction of viscosity and the improvement of process. The increase (31.9%) of LOI value indicated that incorporation of FRC system had obviously improved the flame retardant property of PVC blends. The excellent flame retardant properties were obtained by forming an isolation layer on the surface of PVC blends in the process of FRC burning. FRC could improve the thermal ability of PVC blends by enhancing the decomposition temperature of PVC. The performance in all properties of PVC products could be obtained by controlling the formula blends. Therefore, castor oil-based flame retardant plasticizers would appear suitable for a wide range of application.

Relationship between urinary concentrations of di(2-ethylhexyl) phthalate (DEHP) metabolites and reproductive hormones in polyvinyl chloride production workers

ObjectivesWe investigated the relationship between urinary metabolites of di(2-ethylhexyl) phthalate (DEHP) and reproductive hormones in workers of polyvinyl chloride (PVC) production plants. After exposure, most of the DEHP is rapidly...

Историко-экономический аспект развития производства поливинилхлорида (ПВХ) и изделий из него

Историко-экономический аспект развития производства поливинилхлорида (ПВХ) и изделий из него

ORGANOPHOSPHORUS FLAME RETARDANTS - TOXICITY AND INFLUENCE ON HUMAN HEALTH

Organophosphorus flame retardants (flame retardants, FRs) have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs) - persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexyl)phosphate (TEHP), tris(2-butoxyethyl)phosphate (TBEP), triphenyl phosphate (TPP), tris(2-chloroethyl)phosphate (TCEP), tetrakis(hydroxymethyl)-phosphonium chloride (THPC), tributyl phosphate (TBP), tricresyl phosphate (TCP), tris(2-chloroisopropyl)phosphate (TCPP), tris(1,3-dichloroisopropyl)phosphate (TDCP) and tetrakis(hydroxymethyl)phosphonium sulphate (THPS). In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP). They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs.

A low content Au-based catalyst for hydrochlorination of C2H2and its industrial scale-up for future PVC processes

China has the world's largest polyvinyl chloride (PVC) production capacity, comprising over 20 Mt a−1and occupying 41% of the world production capacity.

Upgrading of PVC rich wastes by magnetic density separation and hyperspectral imaging quality control

Polyvinylchloride (PVC) is one of the most produced polymers in Europe, with a share of 11% in terms of mass (8 milliontons) of total polymer consumption, but in 2010 only 5% of the total PVC production came from recycled materials, where other polymer recycling achieves a level of 15% on average. In order to find an innovative process to extract PVC from window frames waste, a combination of two innovative technologies was tested: magnetic density separation (MDS) and hyperspectral imaging (HSI). By its nature, MDS is a flexible high precision density separation technology that is applicable to any mixture of polymers and contaminants with non-overlapping densities. As PVC has a very distinctive high density, this technology was tested to obtain high-grade PVC pre-concentrates from window frame waste. HSI was used to perform a quality control of the products obtained by MDS showing that PVC was clearly discriminated from unwanted rubber particles of different colors. The results showed that the combined application of MDS and HSI techniques allowed to separate and to check the purity of PVC from window frame waste.

Failure Analysis of Process Equipment Used in the Production of Polyvinyl Chloride

Polyvinyl chloride (PVC) is produced in petrochemical plants by polymerization of vinyl chloride monomer prepared by cracking of ethylene dichloride, which takes place at 500 °C in furnace tubes made of 347 stainless steel. Hydrochloric acid resulting from the cracking process is recycled in the gaseous state and used in an oxychlorination process. However, after less than half the life expectancy, gas leakage has been detected due to a crack in a furnace tube. Another problem has been encountered in the dewatering and drying unit of PVC where the outlet gas at a temperature of 40–60 °C contains 110 ppm of hydrogen. In this case, a dryer support made of 304 stainless steel has fractured. Various electron-optical techniques and x-ray diffraction have been used to characterize the microstructure of damaged materials. The mechanical strength has been evaluated by microhardness measurements. It is concluded that the furnace tube has been damaged by chloride stress corrosion cracking, which is correlated with precipitation of Cr-rich phases including M23C6 carbide and sigma phase due to long-term exposure at elevated temperatures as well as the presence of chloride ions in the environment due to un-cycled HCl. However, the dryer support is found to be damaged by hydrogen-assisted quasi-cleavage.

Energy Efficiency Potentials in the Chlor-Alkali Sector — A Case Study of Shandong Province in China

In this paper, we assess 13 process technologies to improve energy efficiency in the Chlor-Alkali sector of Shandong province in China up to 2025 using a techno-economic approach. The results show energy efficiency improvement (EEI) potentials of 9% in the caustic soda and 38% in the polyvinyl chloride (PVC) production process compared to a frozen-efficiency development. The most influential technologies are energy-efficient electrolysis technology in brine electrolysis step and heat recovery technology in Vinyl Chloride Monomer synthesis (VCM) step. The energy savings can be translated into mitigated CO2 emissions of 10 Mt in 2025. The larger part of this potential is found to be cost-effective from a firm's perspective. In conclusion, significant saving potentials are still available. However, to achieve the all potentials, additional energy policies are needed.

Occurrence of Di-(2-Ethylhexyl) Adipate and Phthalate Plasticizers in Samples of Meat, Fish, and Cheese and Their Packaging Films

Di-(2-ethylhexyl) adipate (DEHA) and phthalates are commonly used as plasticizers to soften polyvinyl chloride products. Because both DEHA and certain phthalates have been identified as priority chemicals for assessment of human health risk under the Government of Canada's Chemicals Management Plan, a comprehensive targeted survey was conducted to investigate the occurrence of DEHA and eight phthalates (di-methyl phthalate, di-ethyl phthalate, di-n-butyl phthalate, di-iso-butyl phthalate, butyl benzyl phthalate, di-n-hexyl phthalate, d-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in a total of 118 samples of meat (beef, pork, and chicken), fish, and cheese packaged mostly in cling films. The eight phthalates were not detected in any of the food packaging, but DEHA was detected in most of the cling films, indicating that although DEHA-plasticized films (e.g., polyvinyl chloride film) are currently being used by most grocery stores, nonplasticized cling films such as polyethylene film, are also being used by some stores. DEHA was not detected in any of the 10 cheese samples packaged in nonplasticized rigid plastics but was detected in all 30 cheese samples packaged in DEHA-plasticized cling films at levels from 0.71 to 879 μg/g, with an average of 203 μg/g. Only DEHA was detected in the beef, pork, chicken, and fish samples packaged in DEHA-plasticized cling films but at considerably lower levels than those found in cheese, with averages of 6.3, 9.1, 2.5, and 5.9 μg/g, respectively. Among the eight phthalates, only di-(2-ethylhexyl) phthalate (DEHP) was detected in a few cheese samples at levels from 0.29 to 15 μg/g, with an average of 2.8 μg/g; these levels were very likely due to environmental contamination. Levels of DEHA found in most of the cheese samples from this study are above the European specific migration limit of 18 mg/kg for DEHA in food or food simulants, and levels of phthalates (i.e., DEHP) were low.

Oral exposure of Kunming mice to diisononyl phthalate induces hepatic and renal tissue injury through the accumulation of ROS. Protective effect of melatonin

Diisononyl phthalate (DINP) has been widely used in polyvinyl chloride (PVC) products and is ubiquitous as a substitute; however, its toxicity due to exposure remains to be determined. This study investigated the oxidative damage induced by DINP and the induced production of the pro-inflammation cytokines interleukin-1 (IL-1) and tumour necrosis factor-α (TNF-α). Oral exposure to DINP induced oxidative damage and inflammatory responses in liver and kidney tissues through the accumulation of ROS, which may be an underlying mechanism for its toxicity. These changes may contribute to hepatic and renal histopathological alterations. Our data suggest that oxidative stress is involved in DINP-induced toxicity and that the co-administration of melatonin exerts a protective effect against DINP-induced toxicity.

Identification of the proteins related to SET-mediated hepatic cytotoxicity of trichloroethylene by proteomic analysis

Trichloroethylene (TCE) is an effective solvent for a variety of organic materials. Since the wide use of TCE as industrial degreasing of metals, adhesive paint and polyvinyl chloride production, TCE has turned into an environmental and occupational toxicant. Exposure to TCE could cause severe hepatotoxicity; however, the toxic mechanisms of TCE remain poorly understood. Recently, we reported that SET protein mediated TCE-induced cytotoxicity in L-02 cells. Here, we further identified the proteins related to SET-mediated hepatic cytotoxicity of TCE using the techniques of DIGE (differential gel electrophoresis) and MALDI-TOF–MS/MS. Among the 20 differential proteins identified, 8 were found to be modulated by SET in TCE-induced cytotoxicity and three of them (cofilin-1, peroxiredoxin-2 and S100-A11) were validated by Western-blot analysis. The functional analysis revealed that most of the identified SET-modulated proteins are apoptosis-associated proteins. These data indicated that these proteins may be involved in SET-mediated hepatic cytotoxicity of TCE in L-02 cells.

Scheduling with multi-attribute setup times on two identical parallel machines

This paper considers a real-life identical parallel scheduling problem originating from the manufacturing plant producing polyvinyl chloride leather products. In the considered scheduling problem, each job has some attributes and each attribute has several different levels. Because there is at least one different level of attribute between two adjacent jobs, it is necessary to make a setup adjustment whenever there is a switch from processing a job to a different job on each machine. The problem can be classified as a scheduling problem to minimize the makespan on two identical parallel machines with multi-attribute setup times. A constructive heuristic, named COIT, is first proposed for the problem and evaluated by comparing with the current scheduling method used by the case plant. To further improve the solution, a variable neighborhood search (VNS) metaheuristic is presented and compared with a mixed integer programming model. The computational results show that the COIT heuristic outperforms the current scheduling method with a significant improvement, and the VNS can further improve the solution.

Mercury Transformation and Distribution Across a Polyvinyl Chloride (PVC) Production Line in China

The production of polyvinyl chloride (PVC) via the calcium carbide process utilizes a catalyst containing large amounts of mercury (Hg) and is therefore one of the most important sources of anthropogenic Hg in China. To measure the emission of Hg from PVC production, we established a flowchart for the calcium carbide process, for which we quantified the Hg content of the material/product at each step. Results indicated that 71.5% of the total Hg (Hg(T)) was lost from the catalyst, most of which was recovered by the Hg remover, accounting for 46.0% of the total Hg (Hg(T)). We determined that 3.7% of the Hg(T) was released into the environment, mostly in solid wastes and byproducts such as hydrochloric acid. Furthermore, no Hg has been detected in the PVC end product. However, we were only able to account for 78.1% of the Hg across the whole system, leaving 21.7% unaccounted for in the mass balance. A rough estimation indicates that most of the "missing" Hg had accumulated in deposits on the inner surface of converters and downstream pipelines; however, the emission to the atmosphere was ≤ 1% of the Hg(T). For a PVC production line equipped with a Hg remover, emissions of Hg to the atmosphere have been estimated to be 4.9 g per tonne PVC. Currently, almost all calcium carbide facilities have been equipped with a Hg remover, which may reduce the release of Hg in China by ∼ 500 t/year.

Experimental Research on Mercury-Containing Wastewater in PVC Production by Fly Ash Processing Calcium Carbide Method

To study the removal capacity of modified fly ash in wastewater containing mercury ions under different conditions, the dust from a calcium carbide furnace was added to fly ash, and the pyrogenic process was employed to modify the fly ash. The result indicated that the wastewater had a pH value of 9, the modified fly ash dosage was 0.2 g, the adsorption equilibrium time was 40 minutes, the reaction temperature was 30 °C, and the removal rate could reach 91.9%. Using modified fly ash in polyvinyl chloride production via the calcium carbide method to remove mercury-containing wastewater can help meet the government-prescribed emission standard. This method has advantages such as positive treatment effect, simple operation, and low operating cost.

Study on Synthesis of Complexes of Maleamic Acid and Lanthanum Ion

Double maleamic acid (DMA) was synthesized with maleic anhydride and ethylenediamine in this paper, and its lanthanide metal complex (LMC) was synthesized in aqueous solution with lanthanum chloride (LaCl).The reaction conditions and the product were determined by UV absorption spectrum, IR spectrum and element analysis. The results showed that the product is La (OH)[C10H10O6N2]·2H2O. And it is the structural formula of speculation. Congo red experiments show that the thermal stability of PVC product was improved significantly after blending with Poly Vinyl Chloride (PVC) and LMC. The thermal stability time can be up to 20 minutes.

Convulsions and hypoglycemia due to tetramethyl succinonitrile intoxication in the polyvinyl chloride (PVC) industry: A 4-year follow-up

Exposure and clinical data concerning cases of toxic convulsions and hypoglycemia due to tetramethyl succinonitrile (TMSN) exposure are reported. Forty-four workers exposed to TMSN in the PVC production plant participated in occupational health medical check-ups including medical history, clinical examination and clinical chemistry. A 4-year follow-up was performed. To evaluate occupational exposure, measurements of TMSN in the ambient air as well as personal air sampling were conducted. Four workers suffered from convulsions with reversible pathologic EEG and 16 other persons were hypoglycemic. Other frequent symptoms included headaches, dizziness and unpleasant taste sensations. TMSN levels had been clearly above the Swiss occupational exposure limit value (MAK). Occupational hygiene interventions resulted in a reduction of the TMSN concentration below the MAK value. TMSN related symptoms have not been observed anymore in the 4-year follow-up. TMSN is a convulsive substance which in humans has also a hypoglycemic effect.

Producing of linoleum with improved physical and mechanical properties

A characteristic feature of the development of various areas of the industry is currently ongoing displacement of traditional metallic materials by plastics. Polyvinyl chloride (PVC) takes one of the leading positions. One of the reasons of extremely rapid growth of PVC production is the fact that there is not another polymer, which could be subjected to such modification varied as it is done with polyvinyl chloride. It is caused by development of technological processes of production, increase of level of development of the equipment for polyvinyl chloride production, quality of raw materials and application of new compositions for achievement of necessary consumer properties of products. The uniqueness of PVC is that according on the production method, formulation and processing technology it provides a large range of polymer materials and products having different properties. For making articles elastic and for simplification of processing of polyvinyl chloride it usually plasticize, thus the content of softener reaches 40%.The most widespread of them are di (2-ethylhexyl) phthalate and dibutyl phthalate. Plasticizers diethylhexyl phthalate and dibutyl phthalate are used for plasticizing cable flexible PVC, linoleum, plastic construction profiles, decorative materials, artificial leather, technical films, products for food, medical and paint industries. However, the most widespread of all other industrial plasticizers dioctylphthalate relatively expensive and deficient. More affordable dibutyl phthalate has high volatility, which prevents its wide application. Therefore, despite the rather large range of plasticizers, their number is insufficient to meet the needs of modern industry. In this regard, the investigation of new plasticizers for PVC materials compositions is relevant and practically significant problem. This paper presents the research of preparation methods and physicochemical properties of oxyalkylated alcohols (butanol, 2- ethylhexanol and phenol) and phthalates on their basis, as well as test results alkoxylated alcohols phthalates as plasticisers in PVC compounding the top layer of linoleum. It is noted that the polymer compositions have a high melt flow values. As showed the conducted researches, PVC formulations of the upper layer of linoleum that we developed with the addition of plasticizers , meet the requirements of existing standards by all indicators, while using butoxylalkylphenoxyalkylphthalate indicators such as petrol – resistance, % (1,25-1,53) and oil resistance, % (10,2-10,8), even superior to standard samples. Akoxylated alcohols based phthalates are potential PVC plasticizers.