The "Safest" Pesticide may contribute to ADHD
Spring is finally here in Southern Ontario, and that means the bugs can't be far away. This is a good moment to remember that we have to be careful with products we use in and around our house because some of them are not as absolutely safe as we may believe.
Pyrethrin has long been touted as the "safest" organic pesticide because it is found in a common garden plant(1). It comes from the chrysanthemum daisy or Pyrethrum, which is often used by vegetable gardeners in companion planting because it is known to repel insects. In its synthetic form, it is the main ingredient in common products like "Raid", "Nix" shampoo for head lice and in "ant powders" we sprinkle around outside when excessive populations of those become hard to control. It is used to kill bugs that eat cotton and wool, to prevent tick-bites and to control mosquito-borne diseases, which are clearly important uses!
This is a substance that is all around us, so it is disturbing to learn that it has been observed in scientific studies to pass through breastmilk and can be measured in the urine of some children (2). We don't know exactly why, but certain children are not able to naturally detoxify from this substance as readily as others. It's more of a problem for boys than girls, and those with higher levels of pyrethrin detected in the urine were apparently 3 times more likely to suffer from symptoms of ADHD. Mice exposed to pyrethrin during their "developmental" period (ie, childhood) also developed symptoms of hyperactivity and reduced focus (3). This happens because pyrethrin works on insects by damaging their nervous system, causing instant paralysis. In larger animals, it causes the nerve cell to lose its ability to relax, making it stay in an excited state all the time.
As a health practitioner, I am always looking for connections between toxic substances and remedies that can be useful for symptoms that look like the result of poisons in our system. There is a remedy in homeopathy made from this same plant known as Tanacetum, or Tansy. Our literature on this remedy goes back as far as 1874, with various authors making reference to behaviours such as restlessness, difficult concentration, foolish gestures, excessive joking or jesting, not answering when spoken to, nervous tics and unwillingness to do work. I find it amazing to uncover such rich connections between substances and symptoms in textbooks written over a hundred years ago!
This does not necessarily mean that Tanacetum is a remedy for the effects of pyrethrin exposure, but it shows that people knew even a long time ago that it was something to be careful with. Please check your cupboards for products that might be harmful and don't believe that everything marked "organic" is absolutely safe in all conditions. Remember that even peanuts are "organic", eaten daily by millions of people with no problem but very harmful to those who are sensitive!
1. "Since Pyrethrins are extracted from Chrysanthemum flowers, it is a sustainable product that fits well into 'green products' ".
4. Pyrethrum induces a toxic effect in insects when it penetrates the cuticle and reaches the nervous system. The pyrethrins that compose pyrethrum bind to sodium channels that occur along the length of nerve cells. Sodium channels are responsible for nerve signal transmission along the length of the nerve cell by permitting the flux of sodium ions. When pyrethrins bind to sodium channels, normal function of the channels is obstructed thereby resulting in hyperexcitation if the nerve cell and, consequently, a loss of function of the nerve cell. The shutdown of the insect nervous system and insect death are most often the consequences of insect exposure to pyrethrins. (http://www.pyrethrum.com/FAQs.aspx)