Standard Vinyl chloride

Automated analyzers may be used for continuous monitoring of ambient poUutants and EPA has developed continuous procedures (23) as alternatives to the referenced methods. Eor source sampling, EPA has specified extractive sampling trains and analytical methods for poUutants such as SO2 and SO [7446-11-9] sulfuric acid [7664-93-9] mists, NO, mercury [7439-97-6], beryUium [7440-41-7], vinyl chloride, and VOCs (volatile organic compounds). Some EPA New Source Performance Standards requite continuous monitors on specified sources. 

Internal Plasticizers. There has been much dedicated work on the possibiUty of internally plasticized PVC. However, in achieving this by copolymerization significant problems exist (/) the affinity of the growing polymer chain for vinyl chloride rather than a comonomer implies that the incorporation of a comonomer into the chain requites significant pressure (2) since the use of recovered monomer in PVC production is standard practice, contamination of vinyl chloride with comonomer in this respect creates additional problems and (J) the increasing complexity of the reaction can lead to longer reaction times and hence increased costs. Thus, since standard external plasticizers are relatively cheap they are normally preferred. 

ASTM D4434, Standard Specification for Poly(Vinyl Chloride) Sheet Roofing, ASTM, Philadelphia, Pa. 

Finally, Sec. 112 of the Clean Air Act required that EPA pronml-gate National Emission Standards for Hazardous Air Pollutants (NESHAPs). Between 1970 and 1989, standards were promulgated for asbestos, beiylhum, mercuiy, vinyl chloride, benzene, arsenic, radionuclides, and coke-oven emissions. 

IX lists the results of some of these experiments, comparing the nitrile materials with polyethylene, the most widely used plastic container material, and poly (vinyl chloride), which is being used for a number of food packaging applications. Note that in all instances there is an order of magnitude difference between the Lopac container and the other two. For flavorants, which are usually present in very low concentrations, this dilute solution test is probably more significant than a standard permeability test which only measures weight losses of the pure ingredient. 

ASTM D 2124-99. Standard Test Method for Analysis of Components in Poly(Vinyl Chloride) Compounds Using an Infrared Spectrophotometric Technique, Annual Book of ASTM Standards, ASTM, West Conshohocken, PA (1999), Vol. 08-01. 

Suitable PLOT columns for the determination of vinyl chloride monomer in PVC include 15.00 m, 0.53 mm bonded polystyrene-divinyl benzene and 30 m, 0.53 mm porous divinyl benzene homopolymer types. Typical responses for vinyl chloride monomer standards (0.06, 0.19 and 0.31 mg/1) in N,N-d imethylaceta-mide expressed as mg/kg vinyl chloride (PVC sample) using the 30 m homopolymer column and flame ionisation detection are shown in Figure 38. An automatic static headspace sampler was employed. 

The Bellar et al. [219] purge and trap method has been applied to the determination of vinyl chloride in seawater. Using the Hall electrolytic conductivity detector, no response was obtained for the acetone used to prepare the vinyl chloride standard solution. 

In contrast to many other countries, chlorinated solvents and the vinyl chain are of minor importance. Carbon tetrachloride (CTC), perchloroethylene (PCE), vinyl chloride monomer (VCM) and ethylene dichloride (EDC) were manufactured for over 40 years by ICI Australia in Sydney, but the facilities were small by world standards and were progressively closed (CTC/PCE in 1991, VCM in 1996 and EDC in 1998) as they were no longer able to compete against imports from world-scale plants overseas. 

A large multicentric cohort study of European vinyl chloride workers revealed a nearly threefold increase in liver cancer based on 24 observed deaths vs. 8.4 expected. The excess was clearly related to time since first exposure, duration of employment, and estimated ranked and quantitative exposures. A cohort study of 10,173 US men who had worked at least 1 year in jobs involving exposure to vinyl chloride confirmed a significant mortality excess in angiosarcoma (15 deaths), cancer of the liver and bilary tract [standardized mortality ratio (SMR) = 641], and cancer of central nervous system (SMR = 180). ° A recent follow-up of this cohort found that excess mortality risk from cancer of the liver and biliary tract, largely due to angiosarcoma, continued risk of mortality from brain cancer had attenuated and excess of deaths from cancer of connective and soft tissue appeared for the first time but was based on few cancers of assorted histology."... 

Commodities are large-volume, low-price, homogeneous, and standardized chemicals produced in dedicated plants and used for a large variety of applications. Prices are cyclic and fully transparent. Petrochemicals, basic chemicals, heavy organic and inorganic chemicals (large-volume) monomers, commodity fibers, and plastics are all part of commodities. Typical examples of single products are ethylene, propylene, caprolactame, methanol, BTX (benzene, toluene, xylenes), phthalic anhydride, poly (vinyl chloride) soda, and sulfuric acid. 

Albert. R.E. (1983) The acceptability of using the cancer risk estimates associated with the radiation protection standard of 5 lems/year as the basis for setting protection standards for chemical carcinogens with special reference to vinyl chloride, Report to Ministry of Labor, Occupational Health and Safety Division, Ibronto, Ontetrio, Canada (Ministry of Labor, Occupational Health and Safety Division, Ibronto, Ontario, Canada). 

Thus far this scheme has been incorporated into OSHA standards for 5 contaminants, i.e., vinyl chloride, acrylonitrile, benzene, lead, and arsenic, and has become a legal requirement of all employers whose personnel may be exposed to these substances. This scheme is likely to be incorporated into virtually all future OSHA standards (15). 

Gold(III) was identified as the most active catalyst for that process in 1985, when Hutchings recognized that the efficiency in catalyzing the hydrochlorination of ethyne to vinyl chloride (a very important industrial process that previously used mercury salts as catalysts) correlated with the standard reduction potential of the supported metal cation. That meant that the metal could be found as a transient species in the reaction [10]. 

Sweeney et al. (1986) studied mortality among 2510 male chemical workers in the United States, followed from 1952 to 1977. Potential exposures included tetraethyl lead (lARC, 1987b), ethylene dibromide (see this volume), 1,2-dichloroethane, inorganic lead (lARC, 1987b) and vinyl chloride monomer (lARC, 1987c). There were 156 deaths (SMR, 0.7) and 38 cancer deaths (SMR, 1.0) observed. There were excesses of cancer of the larynx (SMR, 3.6 90% CI, 0.7-11.5, based on 2 cases) and brain (SMR, 2.1 90% CI, 0.7-4.9, based on 4 cases). The SMR for all lymphatic and haematopoietic cancers w as 0.9 (90% CI, 0.3-1.9, based on 4 cases). Levels of exposure were not reported, but a NIOSH surv ey in 1980 found levels of exposure to 1,2-dichloroethane to be below the recommended NIOSH standard, while lead exposures were elevated. It was not possible to link mortality to any particular chemical exposure. 

Anon, Recommended Standard for Occupational Exposure to Vinyl Chloride , PB-246691, NIOSH, Rockville (1975) [The report recommends, in part, that ... Despite the fact that animal experiments have shown no liver tumors... 

---