marine chlorine Q.; more on VC

[ttweed@wildrockies.org (Tony Tweedale)]

  our regional  rr, MT RailLink, the 2nd worse safety record class C RR in
  the nation, had yet another "oops" on monday (their 8th major derailment in
  western MT since their all-but-the-largest u.s. release of Cl2 gas 18
  months ago near Alberton, MT).  This time it was a 107 car runaway,
  intentionally derrailed @ 40+ mph.  no catastrophic releases,  sheer good
  luck most of the tankers were empty & unpressurized (tho 1 full chlorine
  gas tanker, reportedly).  there were reports of a minor Cl2 leak.  such a
  train, fully loaded & at speed, carries the energy of a major thermonuclear
  device, according to the recent A&E 'investigative reports' documentary
  that highlighted the worst class C carrier, Wisconsin Central (?).  They
  are famous for a  release of benzene causing the too-late evacuation of
  Superior, WI.  WC blew up a propane tanker, as i recall, the same day of
  the Alberton spill.
  
  anyway, one media report said some tankers were carrying "marine chlorine"
  anyone know what this is?
  
  btw, the runaway monday apparantly carried a tanker placarded w/ vinyl
  chloride (ID # 1086, w/ an orange flammable or combustable category 3
  placard)--VC is a gas above 7d F, and is packed into tanker cars under
  pressure but does not dissipate rapidly if released).  VC can cause cancer
  in the lab *AT* the OSHA PEL/"safe" level) of 1 ppm, according to epstein's
  _the politics of cancer_.  VC is a multisite, multiple site of dosing,
  potent human carcinogen; a neurotxin, and a liver & kidney toxin; inter
  alia.  epstein says PVC used to have up to 1% unreacted VC in it.  [that
  reminds me of old batches of 2,4,5-T herbicide, which had 1% (!!!) total
  PCDD/F--that's 10 trillion parts per quadrillion total ccd/f!]
  
  as to the odor question on dioxin-l, epstein says:  "..complaints of an
  unpleasant taste in Schenley Distillers bottles found 10-20 ppm [VC in the
  booze in the PVC bottles]".   NIOSH Pocket Guide to Chem Haz's describes VC
  as "having a pleasant odor at high thresholds" ('high', relative to what?
  ).  In a complex PVC environment, I don't know what the smell that's been
  discussed  is, but note the "pleasant" in the pure VC, and the "unpleasant"
  in the complex booze environment).
  
  
  Tony Tweedale (Causality is a concept not subject to empirical
  demonstration.   -David Hume)