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Re: dioxin fingerprints

  hello again, folks
  TCE formation by ordinary chlorination (with chlorine
  bleach or elemental
  chlorine) is pretty well documented, and appears in the
  public press regularly. I can't point to a study this
  moment, merely
  because I didn't think it was particularly
  controversial - it is accepted
  as fact by the scientific community that I deal with on
  a regular basis.
  I'll attempt to find some studies on it. We are talking
  about a few
  ppb TCE in public water supplies that use chlorine.
  Many publicly
  owned water supplies have stopped using chlorine for
  this reason.
  A few months ago there was an article in The Boston
  Globe about
  the issue, that mentioned just in passing that there
  was concern about
  excess TCE in water supplies that needed to be treated
  with more
  chlorine than usual because of excess coliform. The
  fact that TCE
  was being formed was not part of the controversy; the
  was talking about reducing the amount of TCE by keeping
  water cleaner (fixing broken pipes, etc).
  Now, dioxin formation is another matter. Anytime you
  free chlorine around organics there is the opportunity
  create dioxin. Heat and turbulence improve the chances.
  Consider that in an ordinary washing machine you have
  water temperatures of 140-180 F, a large amount of free
  chlorine (500cc of bleach, which is 5% sodium
  and large amount of organic material (500cc of sodium
  laurel sulfate) agitated heavily. The amounts are
  to be very small. The studies are inconclusive; one
  claimed that most of the dioxin in household washwater
  was from garments treated with dioxin-contaminated
  dyes and fabric "preservative" pesticides - another
  I forgot to mention. Again, as in the case of chlorine
  water treatment, there is no controversy about the
  presence of dioxin in household wastewater, but much
  about where it comes from...
   -----Original Message-----
  From: Susan K. Snow <sksnow@1stnet.com>
  To: Multiple recipients of list
  Date: Wednesday, August 06, 1997 2:40 PM
  Subject: Re: dioxin fingerprints
  >If I recall the lectures I've attended over the years,
  many incinerator
  >companies are said to have dumped their toxic waste
  water (leftover from
  >the process of rinsing air pollution controls and
  creating of steam to
  >produce energy) down the drains.  Perhaps, this may be
  the source of
  >dioxin in POTWs.
  >Susan Snow