I don't think it was your dyslexia showing, as I think many and perhaps most lay people don't have the same understanding of industrial hygiene hazards as we do within the profession. This is why I wanted to detail how we see things, because not just you, but many, many people (especially reporters) do not understand those basic assumptions we have. One of the reasons for my detailed discussion was simply to communicate what for some is a pretty complex and intimidating topic. I hope I succeeded here.
John C. Ratliff Diving since 1959, at age 13. Haven't stopped, and still enjoy getting wet.
and was also wondering about why PVC is used so extensively if it's such a nasty agent for liver-damage/cancer? Correct me if I'm wrong, honestly, but I'm 90% certain they use PVC for nasal-cannulas: the medical industry uses so much, it's hard to imagine where it not used by them! PVC is also used to transport water that we drink everyday... I know I'm crazy, but I was hoping you could clarify thing for me, 'cause now it buggin' me!
You need to know how to read these sheets, even the Wikipedia sheets. If you'll look at the Wiki page you linked, in the upper right there is the technical data on vinyl chloride:
Properties Appearance Colorless gas Density 0.911 g/ml Melting point −153.8 °C; −244.8 °F; 119.3 K Boiling point −13.4 °C; 7.9 °F; 259.8 K Solubility in water 2.7 g/L (0.0432 mol/L)
Note it is a "colorless gas" at normal temperature, and it boils at 7.9 degrees F. So there is no way it is the same material as PVC, which you hold in your hand and is a solid at room temperatures. When in its solid form, vinyl chloride would float on water, except that the water would be solid ice as it would need to be below -244.8 degrees F to be a solid. But PVC is a solid in normal temperatures; what gives? Here's another comment from the same page:
Vinyl chloride is a chemical intermediate, not a final product. Due to the hazardous nature of vinyl chloride to human health there are no end products that use vinyl chloride in its monomer form. Polyvinyl chloride is very stable, storable, and nowhere near as acutely hazardous as the monomer.
Vinyl chloride liquid is fed to polymerization reactors where it is converted from a monomer to a polymer PVC. The final product of the polymerization process is PVC in either a flake or pellet form. From its flake or pellet form PVC is sold to companies that heat and mold the PVC into end products such as PVC pipe and bottles. Tens of billions of pounds of PVC are sold on the global market each year...
Poly-Vinyl Chloride can therefore be used in many products without the health hazards associated with vinyl chloride gas. The vinyl chloride is solidly (pun) bound into the matrix of the PVC, and cannot reek havoc inside the body like the gaseous form can. The vinyl chloride is captured, imprisoned, chained, held, checked, blocked, inside the polyvinyl chloride (PVC) structure so that it cannot enter the body in a manner which would do harm the way vinyl chloride gas can through breathing.