Anonymous ID: 5e5a79 Feb. 14, 2023, 7:49 p.m. No.18349642   🗄️.is 🔗kun   >>9819 >>9957 >>0132 >>0208 >>0229

Looking to focus on vinyl chloride - and (3) different stages of processing and their different toxins hazards.

 

  1. making vinyl chloride vinyl chloride monomer (VCM)

  2. vinyl chloride monomer (VCM) itself in the railcars

  3. PVC polyvinyl chloride - familiar piping

 

  1. The vinyl chloride production process yields vinyl chloride monomer (VCM) which was in the railcars and byproducts and toxins (incl dioxin). These toxins are different than those of the desired end product VCM and are dealt with where the vcm was made in IL.

 

  1. Decomposition VCM in railcars doesn't release dioxin. Fire may release toxic hydrogen chloride (HCl) and carbon monoxide (CO). Serious adverse effects if breathed or consumed. https://19january2017snapshot.epa.gov/sites/production/files/2016-09/documents/vinyl-chloride.pdf

 

  1. Finally, VCM a precursor for a familiar end product PVC (piping etc).

Again, the thermal decomposition of pvc (with additional chemicals used in its manufacture besides vcm) yields different toxins than vcm by itself.

 

Phosgene in the Thermal Decomposition Products of Poly (Vinyl Chloride): Generation, Detection and Measurement

https://academic.oup.com/jat/article-abstract/4/4/166/829587

Anonymous ID: 5e5a79 Feb. 14, 2023, 8:19 p.m. No.18349778   🗄️.is 🔗kun   >>9819 >>9821 >>9957 >>0102 >>0132 >>0208 >>0229

>>18349532

 

PVC and vinyl chloride are two different things.

 

PVC can yield dioxin, vinyl chloride itself no.

 

Vinyl chloride monomer

Main article: Vinyl chloride

In the early 1970s, the carcinogenicity of vinyl chloride (usually called vinyl chloride monomer or VCM) was linked to cancers in workers in the polyvinyl chloride industry. Specifically workers in polymerization section of a B.F. Goodrich plant near Louisville, Kentucky, were diagnosed with liver angiosarcoma also known as hemangiosarcoma, a rare disease.[63] Since that time, studies of PVC workers in Australia, Italy, Germany, and the UK have all associated certain types of occupational cancers with exposure to vinyl chloride, and it has become accepted that VCM is a carcinogen.[9]

 

Dioxins

Main article: Polychlorinated dibenzodioxins

PVC produces HCl upon combustion almost quantitatively related to its chlorine content. Extensive studies in Europe indicate that the chlorine found in emitted dioxins is not derived from HCl in the flue gases. Instead, most dioxins arise in the condensed solid phase by the reaction of inorganic chlorides with graphitic structures in char-containing ash particles. Copper acts as a catalyst for these reactions.[64]

 

Studies of household waste burning indicate consistent increases in dioxin generation with increasing PVC concentrations.[65] According to the EPA dioxin inventory, landfill fires are likely to represent an even larger source of dioxin to the environment. A survey of international studies consistently identifies high dioxin concentrations in areas affected by open waste burning and a study that looked at the homologue pattern found the sample with the highest dioxin concentration was "typical for the pyrolysis of PVC". Other EU studies indicate that PVC likely "accounts for the overwhelming majority of chlorine that is available for dioxin formation during landfill fires."[65]

 

The next largest sources of dioxin in the EPA inventory are medical and municipal waste incinerators.[66] Various studies have been conducted that reach contradictory results. For instance a study of commercial-scale incinerators showed no relationship between the PVC content of the waste and dioxin emissions.[67][68] Other studies have shown a clear correlation between dioxin formation and chloride content and indicate that PVC is a significant contributor to the formation of both dioxin and PCB in incinerators.[69][70][71]