Vinyl chloride detection

NOTE N/A, not applicable N/R, not reported and N/D, not detected. Explosives detection limits at Porton Down 50 mg/L for HMX, RDX, TNT, tetryl 65 mg/L for nitrocellulose 30 mg/L for nitroglycerin. Semivolatile organics (SVOCs) analyzed at Poiton Down 1,4-dichlorobenzene, 2,4- and 2,6-dinitrotoluene, hexachlorobutadiene, nitrobenzene, o-cresol, pentachlorophenol, pyridine, 1,2,4-trichlorobenzene, 2,4,5- and 2,4,6-trichlorophenol. Detection limit on all SVOCs except pyridine was 0.6 mg/L that for pyridine was 0.7 mg/L. Volatile organics (VOCs) analyzed at Potion Down benzene, carbon tetrachloride, chlorobenzene, chloroform, 1,4-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethylene, 1,1,1,2- and 1,1,2,2-tetrachloroethane, trichloroethylene, 2-butanone (methyl ethyl ketone (MEK)), and vinyl chloride. Detection limit was 1 mg/L on all VOCs. 

Fig. 19. Major metabolic pathway for vinyl chloride. ( ), Detected in vitro ( ), detected in...

Reference methods for criteria (19) and hazardous (20) poUutants estabHshed by the US EPA include sulfur dioxide [7446-09-5] by the West-Gaeke method carbon monoxide [630-08-0] by nondispersive infrared analysis ozone [10028-15-6] and nitrogen dioxide [10102-44-0] by chemiluminescence (qv) and hydrocarbons by gas chromatography coupled with flame-ionization detection. Gas chromatography coupled with a suitable detector can also be used to measure ambient concentrations of vinyl chloride monomer [75-01-4], halogenated hydrocarbons and aromatics, and polyacrylonitrile [25014-41-9] (21-22) (see Chromatography Trace and residue analysis). 

It is also not tme that vinyl plastics decompose in landfills and give off vinyl chloride monomer, because like all plastics, vinyl is an extremely stable landfill material. It resists chemical attack and degradation, and is so resistant to the conditions present in landfills that it is often used to make landfill liners. On those occasions when vinyl chloride monomer is detected in landfills, it typically can be traced to the presence of other chemicals and solvents. 

Multienzyme electrodes can increase sensitivity from micromolar to nanomolar detection levels (53,57). In this case the substrate is converted to a detectable product by one enzyme, then that product is recycled into the initial substrate by another enzyme resulting in an amplification of the response signal. For example, using lactate oxidase and lactate dehydrogenase immobilized in poly(vinyl chloride), an amplification of 250 was obtained for the detection oflactate (61). 

The hazards of chemicals are commonly detected in the workplace first, because exposure levels there are higher than in the general environment. In addition, the exposed population is well known, which allows early detection of the association between deleterious health effects and the exposure. The toxic effects of some chemicals, such as mercury compounds and soot, have been known already for centuries. Already at the end of the eighteenth century, small boys who were employed to climb up the inside of chimneys to clean them suffered from a cancer of the scrotum due to exposure to soot. This was the first occupational cancer ever identified. In the viscose industry, exposure to carbon disulfide was already known to cause psychoses among exposed workers during the nineteenth century. As late as the 1970s, vinyl chloride was found to induce angiosarcoma of the liver, a tumor that was practically unknown in ocher instances. ... 

A wide variety of methods have been developed for the detection of residual monomers in polymeric materials. Volatile monomers, for example, acrylonitrile, butadiene, vinyl chloride, etc., are normally determined using headspace GC methods. 

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. 

Figure 38 Detection of vinyl chloride monomer (VCM) by headspace GC.

It appears that Charlton et al.94,95 have discovered the first methods for reversible and continuous optical measurement of the clinically highly important alkali and earth alkali ions. In one approach94 they use plasticized poly(vinyl chloride) along with valinomycin as the ion carrier, and a detection scheme that was later refered to as co-extraction. In their system, potassium ion is extracted into plasticized PVC, and the same quantity of the anionic red dye erythrosine is co-extracted into it. The extracted erythrosine is quantified via absorbance or reflectance. 

Besides, potentiometric sensors with ion-selective ionophores in modified poly(vinyl chloride) (PVC) have been used to detect analytes from human serum [128], Cellular respiration and acidification due to the activity of the cells has been measured with CMOS ISFETS [129], Some potentiometric methods employ gas-sensing electrodes for NH3 (for deaminase reactions) and C02 (for decarboxylase reactions). Ion-selective electrodes have also been used to quantitate penicillin, since the penicillinase reaction may be mediated with I or GST. 

Vinyl chloride monomer (VCM) is the main substrate for the manufacture of polymers used as packaging materials for food. Since VCM is considered by lARC to be a human carcinogen, monomer levels in PVC food packaging materials are strictly controlled. To ensure a safe product, the residual content of VCM in the finished material or article is limited to one mg per kg in the final product (Council Directive 78/142/EEC). Furthermore, VCM should not be detectable in foodstuflfs. Commission Directives 80/766/EEC and 81/432/ EEC give the method of analysis for official control of the VCM level in food packaging materials and in foods - gas-phase chromatography using the headspace method, after dissolution or suspension of samples in N,N-dimethylacetamide. Both residual monomer content of the polymer and... 

From these mechanistic studies, specific biomarkers of effective exposure were proposed the DNA adducts ethenodeoxyadenosine and ethenodeoxycytidine. These can be detected in liver biopsy and white blood cells and so can be used to monitor workers. Furthermore, more recently, a specific biomarker of response has also been detected. This is a mutant p21 ras protein, which results from the interaction with DNA and can be detected in the serum of workers exposed to vinyl chloride. The level of this protein detected in workers was found to have increased as exposure to vinyl chloride increased. Therefore, both these biomarkers can be used in risk assessment. 

Vinyl chloride is a chemical used in the manufacture of plastics, which is carcinogenic and causes various toxic effects, including liver injury and damage to the bones and skin. Liver hemangiosarcomas are produced in animals and humans. Vinyl chloride undergoes metabolic activation by cytochrome P-450 to an epoxide, which may interact with DNA and form adducts (ethenodeoxyadenosine and ethenodeoxycytidine), which leads to mutations. These can be detected in white cells, and a mutant p21 ras protein can be detected in the serum of exposed workers. Also, reaction with GSH occurs. 

Chloroprene has been detected as an impurity at levels of several parts per million in commercial vinyl chloride in Italy (Sassu et al., 1968) and in Japan (Kurosaki et al., 1968), and in acrylonitrile in the USSR (Panina Fain, 1968). 

Dichloroethane is used mainly in the production of vinyl chloride. It is no longer registered as a fumigant. It has been detected at low levels in ambient and urban air, groundwater and drinking-water. 

Laumbach, A.D., Lee, S.. Wong, J. Streips. U.N. (1977) Studies on the mutagenicity of vinyl chloride metabolites and related chemicals. Prev. Detect. Cancer, 3, 155-170... 

Vinyl Chloride Yes (500ppm, intermittent) 20 Cardiovascular 500 (rat LD50) None detected Inhalation 2 3... 

Zell-lgelit. Ger WWII porous vinyl chloride polymer laminate which was used as a coating on the air intake tube (schnorkel) and periscope of submarines to prevent detection by radar bearing aircraft... 

Several chlorinated and brominated alkenes are present in emissions of Mt. Etna, Vulcano, Kuju, and Satsuma-Iwojima (217). In addition to vinyl chloride (10), TCE, PERC, and 1,1-dichloroethylene, compounds 11-57 were detected in these emissions. For many of these compounds, exact structures remain unknown. 

Although hexachlorobenzene (HCB) was used as an active component of insecticides and fungicides in the UK until the 1970s, its major source to the environment now is now as a by-product of industrial processes such as aluminium smelting and production of perchloroethylene and vinyl chloride monomer.65 The MAFF survey mentioned earlier did not include HCB, but a later survey on milk samples from farms around potential point sources did analyse for HCB. No HCB was detected at or above the reporting limit of 1 fig/ kg in whole milk in samples from either around potential point sources or control farms.66... 

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