Polychlorinated biphenyls plasticizers

Polychlorinated biphenyls (PCB) L S A Lubricants and hydraulic fluids Pesticides Plasticizer in paint and polymers Plasticizer (polymers) Transformer oils... 

The important influence that sample container materials can have on seawater sample composition is illustrated next by two examples one concerning the storage of metal solutions in glass and plastic bottles, the other concerning the storage of solutions of phthalic acid esters and polychlorinated biphenyls in glass and plastic. 

Polychlorinated biphenyls (PCBs), known by their trade marks of Arochlor (Monsanto U.S.), Phenochlor (in France), and Clophen (in Germany) are chemically similar to the chlorinated insecticides. Although not used for this purpose, their existence and persistence in the environment is well established. They were used to make more flexible and flame retardant plastics and are still used as insulating fluids in electrical transformers since there is no substitute in this application. They have been made by Monsanto since 1930 and were first discovered as a pollutant in 1966. U.S. production peaked at 72 million lb in 1970 but in 1975 it was down to 40 million Ib/yr because in 1971 Monsanto voluntarily adopted the policy of selling PCBs only for electrical systems. At least 105 PCBs are present in the environment. 

The Universal Demercurization Process, or UNIDEMP , is an ex situ process for removing mercury from a variety of solid and aqueous mercury waste streams such as metals, concrete, soils, asbestos, plastic, and cable as well as amalgams and mercury compounds. The process can also treat polychlorinated biphenyls (PCBs) and halogenated organics. UNIDEMP is a mobile system that volatizes and condenses mercury in a countercurrent rotating furnace at temperatures from 550 to 650°C. Celsius. 

According to the vendor, ZEROS can treat hydrocarbons and chlorinated compounds such as polychlorinated biphenyls (PCBs) and dioxins. The vendor claims that the technology can treat contaminated soils, liquid wastes in metal and plastic containers, asbestos, medical and biomedical wastes, contaminated sludges, waste fuels, fuel residues, and municipal solid waste. The technology is commercially available. 

The development of plasticizers has been plagued with toxicity problems. Thus the use of highly toxic polychlorinated biphenyls (PCBs) has been discontinued. Blood stored in plasticized PVC blood bags and tubing may extract phthalic add esters, such as DOP. These aromatic esters are also distilled slowly from PVC upholstery in closed automobiles in hot weather. These problems have been solved by using oligomeric polyesters as nonfugitive plasticizers instead of DOP. 

Polychlorinated Biphenyl (PCB) Polychloropolyphenyls Polyformaldehyde Pclyisobutylene Plastics Polyisobutylene Resins Polyisobutylene Waxes Polyhethylene Polyphenyl Isocyanate Polyoxpropylene Ether, PPG Poly(Oxyethyl) Dodecyl Ether Poly(Oxyethyl) Lauryl Ether... 

Environmental chemicals and pollutants are also capable of inducing P450 enzymes. As previously noted, exposure to benzo[a]pyrene and other polycyclic aromatic hydrocarbons, which are present in tobacco smoke, charcoal-broiled meat, and other organic pyrolysis products, is known to induce CYP1A enzymes and to alter the rates of drug metabolism. Other environmental chemicals known to induce specific P450s include the polychlorinated biphenyls (PCBs), which were once used widely in industry as insulating materials and plasticizers, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin, TCDD), a trace byproduct of the chemical synthesis of the defoliant 2,4,5-T (see Chapter 56). 

The polychlorinated biphenyls (PCBs, coplanar biphenyls) have been used in a large variety of applications as dielectric and heat transfer fluids, lubricating oils, plasticizers, wax extenders, and flame retardants. Their industrial use and manufacture in the USA were terminated by 1977. Unfortunately, PCBs persist in the environment. The products used commercially were actually mixtures of PCB isomers and homologs containing 12-68% chlorine. These chemicals are highly stable and highly lipophilic, poorly metabolized, and very resistant to environmental degradation they bioaccumulate in food chains. Food is the major source of PCB residues in humans. 

NOTE Chlorine is widely used in the protection of drinking water, the manufacture of pharmaceuticals, crop pesticides, paper, rubbers, resins and plastics, and thousands of other products. Nevertheless, since the early 1990s, there has been a groundswell of opinion to either ban or severely limit the use of chlorine in all manners of processes. This is based on observations associated with the probable adverse effect to the environment from certain chlorinated organic chemicals, such as polychlorinated biphenyl (PCB) and the insecticide DDT. There is also concern in a number of other areas, for example, that free chlorine may contribute to effluent toxicity due to the formation of chloramines and trihalomethanes (THMs). In the United States in 1993 to 1994, this opinion was fueled by the possibility that the Environmental Protection Agency (EPA) would... 

PCB organic compounds found as soil and water contaminants continue to grow each year. They include polychlorinated biphenyls (PCBs), phenols, cyanides, plasticizers, solvents, and numerous industrial chemicals. PCBs were historically used as coolants in electrical transformers and are also known by-products of the plastic, lubricant, rubber, and paper industries. They are stable, lipophilic, and break down only slowly in tissues. Because of these properties they accumulate to high concentrations in fish and waterfowl in 1969 PCBs were responsible for the death of thousands of birds in the Irish Sea. 

Similarly, many xenobiotics, such as pesticides, polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), plasticizers, phenols, and some other dmg residues, are also toxic even at trace levels present in the earth s ecosystem [5-7], Without analytical techniques capable of detecting them at nanolevels, we assume the absence of these pollutants in the environment, while these notorious pollutants accumulate in our body tissues resulting in various diseases and side effects such as carcinogenesis and failure of many vital body organs including the kidney, liver, and heart [8-11]. Under such situations, it is essential to have analytical techniques that can detect dmgs, pharmaceuticals, and xenobiotics in biological and environmental samples at very low concentrations. 

Giam CS, Chan HS, Neff GS. 1978b. Phthalate ester plasticizers, DDT, DDE and polychlorinated biphenyls in biota from the Gulf of Mexico. Marine Pollution Bulletin 9 249-251. 

Jansen and co-workers [86] have evaluated temperature-controlled outgassing processes of plastics and rubbers using both off-line and on-line TD-GC-FTIR-MS. Decomposition of polyesterurethanes by means of TG-Tenax off-line sampling followed by TD-GC-FTIR-MS revealed C02, H20, tetrahydrofurane, cyclopentanone, dicarbonic acid, aliphatic diols and esters [86]. The same authors have also described the detection of polychlorinated biphenyls (PCB) in 2,4-dichlorobenzoylperoxide cured silicone rubbers after outgassing products of a rubber silicone part obtained after desorption for 10 minutes at 200 °C in the thermal desorption cold-trap and subsequent analysis by means of TD-GC-MS. Using a mass range of 290-294 Da the MS can be used as a selective detector for these substances. 

Polychlorinated biphenyls (PCBs) are mixtures of biphenyls with 1 to 10 chlorine atoms per molecule. They are oily fluids with high boiling points, great chemical resistance, and low electrical conductivity, and have been used as plasticizers in polyvinyl polymers, insulators and coolants in transformers and heat exchange fluids. Dioxins and furans (see Section 9.1) are not produced intentionally but are derived from combustion processes of chlorinated aromatic hydrocarbons, pesticides and chlorinated solvents. 

Polychlorinated biphenyls (PCBs) were produced from 1930 to 1983 in the form of complex mixtures for a variety of uses (e.g. dielectric fluids in transformers and capacitors, and plasticizers in paint and rubber sealants). Because of their physical and chemical stability, and also of their lipophilic affinity, they are highly persistent and tend to accumulate in sediments and biota in the aquatic environment [253]. 

Polychlorinated biphenyls (PCBs) were used in electrical capacitors, electrical transformers, vacuum pumps, and gas transmission tribunes. They were also used as hydraulic fluids, plasticizers, adhesives, fire retardants, wax extenders, lubricants and cutting oils, inks, dedusting agents, etc. PCBs are no longer commercially produced in the United States but are still found in the environment. PCB s have been found in at least 500 of the 1598 National Priorities List Sites identified by the Environmental Protection Agency (EPA). 

Phosphoric Acid Phosphorus Photoallergens Photochemical Oxidants Phthalate Ester Plasticizers Physical Hazards Picloram Picric Acid Piperazine Piperonyl Butoxide "Plants, Poisonous" Platinum (Pt) Plutonium (Pu) Poinsettia Poisoning Emergencies in Humans Pokeweed Pollutant Release and Transfer Registries (PRTRs) Pollution Prevention Act "Pollution, Air" "Pollution, Air Indoor" "Pollution, Soil" "Pollution, Water" Polybrominated Biphenyls (PBBs) Polybrominated Diphenyl Ethers (PBDEs) Polychlorinated Biphenyls (PCBs)... 

The saga of brominated flame retardants offers a cautionary tale for the chemical industry.65 These chemicals, developed in the early 1970s, are used in a wide range of consumer products, such as furniture, foam, and plastic casings of electronic devices. In 1998, Swedish scientists reviewing archived human breast milk samples discovered that certain flame retardant chemicals (polybrominated diphenyl ethers, or PBDEs) had doubled in concentration in Swedish breast milk about every five years over the preceding twenty. This was a source of concern, as studies of laboratory animals had shown that PBDEs dismpt thyroid hormones. Such dismption yields neurobehavioral effects similar to those of PCBs (polychlorinated biphenyls), whose manufacture the United States banned in 1976. 

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