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Chemicals  -- Air Conditioning Serviceman,

even Weed Killers can have some serious consequences!


---- Sharing my thoughts and experiences ----

Something to consider is the impact on the thyroid from chemicals such as: lawn treatments, flea/tick drugs, pesticides, cleaning products, shampoos, vaccinations, heartworm drugs, etc.  Who knows what the combination of them can do to a body when the tests are done in isolation?  In other words, chemicals such as pesticides are tested individually, however, when tested with other chemicals, the results may be different.  Also, the so-called 'inert' ingredients may not be harmless.

Years ago, while walking my dogs, I witnessed my neighbor who has horses and goats, spraying his pasture.  He told me he was using weed killer, and I let him know that dangerous chemicals are linked with many health problems and could also contaminate our wells.  He said that he thought he should be wearing a mask.  I let him know that I'd send him the following article (which I did), and then I turned around and went another route home.

A few weeks afterwards, Oliver, our former "top cat" exhibited symptoms of poisoning.  He was treated with conventional veterinary medicine and homeopathy.  He seemed to recover and then got sick again about a month later.  Doing better, but still not back to normal, he went out one day and never came home.

The fact that a couple of my cats hunt in that field sprayed with weed killer did not go unnoticed.  We have pet doors and all but two of our cats hang out on the sun porch, the deck or in the fenced yard.  One way of preventing another occurrence was to have an animal communicator inform Oliver and Jujube of the danger in eating prey in that field -- but it was too late for Oliver, the damage was done.  Several years later, Jujube was diagnosed with kidney failure -- the second most frequent cause of death in cats.  In the 30 years of sharing my life with cats, he was the only one who had kidney disease.  Sadly, he was unable to recover.

Several years later, during the summer of 2004, my husband didn't feel well and I got very sick with a prolonged (whooping-type) cough shortly after a serviceman used an "antimicrobial" spray while cleaning our whole-house A/C unit.  I consider myself a healthy person and am hardly ever sick.  A few weeks later I started putting  together the pieces and was intrigued by the very unusual simultaneous occurrences, such as many of my houseplants (including orchids) dying,  one of my dog's sudden strange skin condition, and a weird build-up on the air purifier -- things that had never happened before.

Remembering that awful odor of a 'chemical-type smell along with a synthetic fragrance' when the serviceman turned on the A/C system, and, despite my husband's report that the guy said it was "non-toxic" -- I'd aired out the house for over an hour anyway.  Then, I recalled that experience with a prior A/C serviceman from a different company, there was no 'chemical-type smell  or any synthetic fragrance' when the job was done. In fact, I'd accompanied that serviceman during the cleaning and he explained to me how the heat pump system works.

So, I decided to find out what this latest serviceman used in our whole-house A/C unit, just out of curiosity.  According to the label on the product it contained Chlorine Dioxide which turns out it's an EPA registered Pesticide, a Bacteriostat, Fungistat, Germistat and All-purpose Deodorizer.

Note: In 2006, while attending a big dog show in SC, I became aware of a strong 'bleach odor' in the air.  Looking around, I didn't see anyone doing a clean-up --  but noticed that the overhead ventilation system blowing the heated air into the expo center.  I immediately left and afterwards my throat was sore for a couple of days.

EPA Definition of a Pesticide

What is a pesticide?

A pesticide is any substance or mixture of substances intended for:

  • preventing,
  • destroying,
  • repelling, or
  • mitigating any pest.

Though often misunderstood to refer only to insecticides, the term pesticide also applies to herbicides, fungicides, and various other substances used to control pests.

Under United States law, a pesticide is also any substance or mixture of substances intended for use as a plant regulator, defoliant, or desiccant.

  • Desiccants promote drying of living tissues (mucus membranes, parts of growing plants)

  • Defoliants make the foliage, leaves, etc. drop off.

Do household products contain pesticides?

Many household products are pesticides. All of these common products are considered pesticides:

  • Cockroach sprays and baits
  • Insect repellents for personal use.
  • Rat and other rodent poisons.
  • Flea and tick sprays, powders, and pet collars.
  • Kitchen, laundry, and bath disinfectants and sanitizers.
  • Products that kill mold and mildew.
  • Some lawn and garden products, such as weed killers.
  • Some swimming pool chemicals.

What is the balance between the risks and benefits of pesticides?

By their very nature, most pesticides create some risk of harm - Pesticides can cause harm to humans, animals, or the environment because they are designed to kill or otherwise adversely affect living organisms.

What concerned me most was my exposure to the chemically-laden air in my house after the serviceman turned the system back on. My husband saw the serviceman saturate the whole inside of the A/C unit and didn't rinse it or dry the chemical off.  My husband  then went golfing for that day and the next two days.  I was inside and breathed in the chlorine dioxide which evaporated from the inside of the coils, etc..  To my way of thinking this was Chlorine Dioxide Gas, and from memory, seems this may be detrimental to health.

Afterwards, I had the serviceman come and rinse the A/C unit, but to me, the damage was done.  I later wrote about it which included the name of the product and manufacturer.  However, in March, 2005, I received a threatening letter from the lawyer of the gigantic multi-national company and therefore removed the name of the product and the company from my article.

The EPA requires pesticide product registrants to submit adverse effects information about their products

So, I've contacted the National Pesticide Information Center, 800/ 858-7378, sent along my letter to the company -- for the record -- and copied:

US-EPA (7506C)

Ariel Rios Building
1200 Pennsylvania Ave., NW
Washington, DC 20460-2403


Document Processing Desk -6(a)(2)
Office of Pesticide Programs- 7504C
U.S. Environmental Protection Agency
Ariel Rios Building
1200 Pennsylvania Ave., NW
Washington, DC 20460-0001


Chlorine dioxide - Identification, toxicity, use, water pollution potential, ecological toxicity and regulatory information

Signs and Symptoms of Chlorine dioxide Poisoning

Symptoms of Chlorine dioxide Exposure from the International Program on Chemical Safety/International Chemical Safety Cards ICSC)




Reacts with water to produce hydrochloric acid and chloric acid.


The gas is heavier than air.


The substance can be absorbed into the body by inhalation.

A harmful concentration of this gas in the air will be reached very quickly on loss of containment.

The substance is severely irritating to the eyes , the skin and the respiratory tract .
Inhalation of gas may cause lung oedema (see Notes). Exposure far above the OEL may result in death. The effects may be delayed. Medical observation is indicated.

The substance may have effects on the lungs , resulting in chronic bronchitis.

The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. Immediate administration of an appropriate spray by a doctor or a person authorized by him/her should be considered. Rinse contaminated clothes (fire hazard) with plenty of water.

 Note: Information for many chemicals is incomplete and may not be fully representative of effects on humans. Why?


WARNING! Limitations of Available Human Toxicity Data

Human toxicity data do not exist for many chemicals, which makes it difficult to draw firm conclusions about the probable toxicity of a compound. Toxicity tests on laboratory animals are more readily available, with U.S. EPA requiring a certain minimum set of studies for different kinds of toxicity before the chemical is registered (1). In spite of these precautions, there are a number of reasons that the available toxicity data may not accurately reflect the hazard potential of the chemical to humans, including: [excerpt]


  • In laboratory studies, the test animal is exposed to only a single chemical. In the environment, humans are exposed to multiple toxins simultaneously, which can lead to additive or synergistic effects.
  • Not all types of toxicity are studied in detail. The incidence of some diseases linked to chemical exposure have increased substantially in industrialized countries over the last 30 years or so. Attention Deficit Disorder (ADD), Attention Deficit Hyperactivity Disorder (ADHD), asthma, early onset of menstruation, multiple chemical sensitivity, certain diseases related to immune system dysfunction, and others. Yet although there is evidence that these diseases have been linked to chemical exposure, the science of understanding the mechanisms of these interactions is not far enough along for regulatory agencies to test a chemical for the potential to cause these effects. ...
  • The process by which chemicals are prioritized for study or included on an official toxicity list (carcinogens, reproductive toxins, etc.) can be as much political as it is scientific. Some chemicals have escaped extensive scrutiny because of interference from the chemical industry.
  • Fewer independent studies (those conducted by someone other than the pesticide manufacturer) have been conducted on newly registered chemicals, resulting in the appearance that they are less hazardous than those that have been on the market for a longer time and have been more thoroughly studied. While it is often true that these chemicals are less hazardous than the older chemicals, there is no way to be sure this is actually true until 15-20 years have elapsed and the unanticipated side effects have become apparent. ..."

    Please click on the two Links below read the following two articles:

    Pesticides and Aggression

    Caution with Chemical Products used in Air Conditioning Units!


    Copyright 1995 Helen L. McKinnon All Rights Reserved

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