Professor Abou-Donia's team demonstrated...combinations of toxic pesticides are far more damaging than any (single) compound (active ingredient) acting on its own. 

When they combined three compounds at "safe" level for chlorpyrifos and others, they produced an effect on the laboratory animals which was equivalent to the lethal dose of chlorpyrifos

 

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[ MEMORIAL TO VICTIMS ]

Subject:   Sound Science Discusses Synergism---------
Date:      Fri, 21 Apr 2000 09:06:15 -0400
From:        Stephen Tvedten <steve@getipm.com>
Organization:     Get Set Inc. (www.getipm.com)

To:     Lyndon Hawkins <hawkins@empm.cdpr.ca.gov>
          Senior Research Scientist
          State of California, Department of Pesticide Regulation - Integrated Pest Management

Dear Lyndon:

 I thought you might be interested in an article from The Journal of Pesticide Action Network UK, Pesticides News, March 2000 entitled:  Research shows dangers of chemical mixes; Research on laboratory hens in the US shows how toxic OPs can be in combination with other ("registered") pesticides.  

At Duke University in North Carolina, Mohammed Abou-Dania, professor of neuro-biology and neuro-toxicology and his team established the lethal dose for chlorpyrifos.  Their next finding was extraordinary; when they combined three compounds which had proved to be "safe" used at the correct levels (labeled rates) on their own, the toxicity shot up.  'When they combined three compounds at "safe" level for chlorpyrifos and others, they produced an effect on the laboratory animals which was equivalent to the lethal dose of chlorpyrifos."...  

In their laboratory, Professor Abou-Donia's team demonstrated...combinations of toxic pesticides are far more damaging than any (single) compound (active ingredient) acting on its own.  Apart from chlorpyrifos, Professor Abou-Dania's team used permethrin, a synthetic pyrethroid (SP), and DEET, an insect repellent which Dr. Jamal said was not toxic by itself.  All three compounds were used by UK and US troops in  the Gulf War...  

'Unfortunately, no-one is telling farmers (or anyone else) about this (dangerous synergistic) combination effect because it has never been tested as part of establishing the chemicals' safety and there are no hazard warning labels on the chemical containers about this possible (synergistic) effect.'  OPs also contained (unknown "inert") solvent combinations which are toxic by themselves but their combination effect with the active ingredients is unknown...  

When chemicals combine in this way, said Dr. Jamal, they have three (known) effects on people:  some chemicals bind to enzymes which (try to) de-toxify the body and make them unavailable to do their work on other chemicals expressed simultaneously.  'This is rather like releasing 200 criminals in London and taking away the police officers who are usually on duty,' said Dr. Jamal.  'There is bound to be some damage.'  

In 1998, a group of Israeli scientists demonstrated the second effect across what is called the blood-brain barrier, the brain's protective shield.  They showed that subjecting laboratory animals to the kind of stress endured from a combination of chemicals undermined the protective role of the blood brain barrier and allowed toxic substances freer access to the central nervous system.  'The gates of the blood brain barrier are almost fully opened and toxic substances in the blood have been shown to cross the protective shield more than one hundred fold higher, thereby gaining direct access to the nervous tissue," said Dr. Jamal.  Thirdly, body tissue exposed to the combination becomes more and more sensitive.  

In 1997, Dr. Jamal published a paper in which he tried to distinguish the long-term effects of OPs from the acute and delayed effects already accepted by company and Government scientists.  He described a neurotoxic effect called organophosphate induced delayed neuropathy (OPIDN) which usually happens two or three weeks after (acute) exposure...  

Dr. Jamal outlined another phenomenon called COPIND - or chronic OP-induced neuropsychiatric disorder.  COPIND has a different pathology from OPIDN, and all OPs  produce the disorder by their impact on the cortical nerve cells in the higher brain.  'My contention is that because we are talking about the issues such as abstract thought and memory, COPIND cannot be tested on laboratory animals.  So far, the chemical industry has ignored COPIND completely despite the presence of many studies in the literature'...  

The US environmental protection agency's (EPA's) health statistician estimated that 7,000 chlorpyrifos poisonings were reported during 1996, the most recent year for which data is available...  

Well, Lyndon, sound science is clearly proving your "registered" poisons are not properly "tested or registered or safe"!  I would like to point out that whenever your "certified" applicators spray your "registered" POISONS with their sprayers, there normally are some "registered POISONS" in their sprayer from the previous jobs.  So, the ever changing toxic brew they are actually spraying is totally untested and the potential dangers from all of the various synergistic combinations of active ingredients, "inerts", metabolites, contaminants, etc. is impossible to compute or dare I say it ---- to "register".  Knowing this, how can you pretend that safe and far more effective alternatives are "illegal" in California?  

       Respectfully,

        Stephen L. Tvedten

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