Re: question

["Jon Campbell" <jon@cqs.com>]

  Hi, Byron
  
        You are right; the chlorophenoxy herbicides are certainly the
  threat-of-the-day (and paraquat, if it is still used...). I believe 2,4-D is
  still the most popular herbicide...and is measurably contaminated with
  dioxins and furans. But I think the other organochlorine pesticides are
  still popular in many countries. Also, common pesticides such as Dursban
  (chlorpyrifos), for instance, may "break down" quickly, but I doubt whether
  its breakdown products are biodegradable, and they, like DDE from DDT, are
  probably pretty nasty. The chlorine-carbon bond is very strong...
  
  Thanks
  Jon
  -----Original Message-----
  From: Byron Bodo <bodo@interlog.com>
  To: jon@cqs.com <jon@cqs.com>
  Date: Friday, December 26, 1997 2:44 AM
  Subject: Re: question
  
  
  >At 03:22 PM 25/12/97 -0500, you wrote:
  >>Hello, Byron,
  >>
  >>      If dieldrin is no longer produced, then I stand corrected; I guess
  my
  >>sources are outdated. The growers have undoubtedly changed to some equally
  >>nasty organochlorine pesticide
  >
  >The only persistent OCs still used to any extent in some parts are lindane
  >& DDT, the latter mainly for anti-malarial prophylaxis.  Arguably, dicofol
  >ranks with these as well, but info on who/where/how much is being
  >used isn't easy to come by.  The OPs, pyrethroids & other later generation
  >insecticides overwhelmingly dominate globally.  I doubt PCDD/Fs
  >are much of an issue with these.  Rather it's the acute toxicity & the
  >poisoning of the sprayers & handlers.  Most have very short half lives.
  >
  >For PCDD/F content, chlorophenolic derived derived herbicides
  >were probably the greatest threat.  Not really sure how much & where
  >these were/are being used, other than agent orange & some sketchy
  >info on some herbicides used in certain rice growing countries.
  >
  >-bb
  >
  >