Really liked Youbet's posting (#18)!
I have been avoiding brush-cutting for the last two summers, ever since i contracted Babesiosis. This is yet another tick-borne disease and presumed to be at least as common as Lyme disease. Very similar epidemiology, but the medical establishment has not caught up to it yet - the diagnostic testing is not as developed as it is for Lyme... I went through 2 months of lethargy and weakness before I started peeing coffee-colored urine. [That's hemoglobin residue from destroyed red blood cells!] It's easier to treat than Lyme, but the diagnosis is frequently missed by the medical establishment because they typically only test for Lyme. It was only after I ended up in the ER that it was diagnosed! The prescribed treatment (antibiotic and antiparasitic) provides a complete cure.
[For you cattlemen, this disease is the same as Texas Cattle Fever in cattle!]
Seems that, in 1994, the US Army studied the effects of permethrin-impregnated BDUs on the health of soldiers. I found this paper at the NIH website:
Summary - Health Effects of Permethrin-Impregnated Army Battle-Dress Uniforms - NCBI Bookshelf
They considered dermal exposure only. They looked at both acute and chronic toxicity. They looked at dermal, ocular, neural, liver, immune, gene, reproductive, and developmental toxicity. They also looked at carcinogenicity.
Here are the conclusions:
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The subcommittee analyzed the risk of adverse health effects to soldiers who wear permethrin-impregnated BDUs and the risk to garment workers who handle permethrin-treated fabric. Based on the review of the toxicity data on permethrin, the subcommittee concludes that soldiers who wear permethrin-impregnated BDUs are unlikely to experience adverse health effects at the suggested permethrin exposure levels (fabric impregnation concentration of 0.125 mg/cm2). The risk of adverse health effects in garment workers who handle permethrin-impregnated fabric is even smaller because their exposure to permethrin is estimated to be less than that of soldiers.
Permethrin-impregnated BDUs are effective in preventing insect-borne diseases in military personnel in insect-infested field areas. The most beneficial use of permethrin-impregnated BDUs will be in overseas field settings, where exposure to disease-bearing insects is substantial. The risk of vector-borne disease in the United States is considerably less but not zero. Military personnel wearing permethrin-impregnated BDUs in field operations in the United States will benefit from protection from tick and mosquito bites, which, in turn, will protect them from endemic diseases, such as Lyme disease, Rocky Mountain spotted fever, and viral encephalitis. They will also be protected from other routine insect bites that often become infected and require medical treatment.
The subcommittee notes that in situations where soldiers are in protected environments, such as offices, where insect contact is remote, there is no tangible benefit from wearing impregnated BDUs."
My personal conclusion is that the toxicity is NOTHING compared to a tick-borne disease!
I did some calculations and if a 36.8% solution of permethrin concentrate is mixed 2 oz/gallon of water, using the Army's 0.125 mg/cm2 'dose', then about 10 square yards of clothing can be treated with a quart of diluted solution. I figure a T-shirt or a pair of pants is about 1 square yard...
Looks like Youbet was diluting the concentrate 1.7 oz/gallon. I'm going to go with 2 oz/gallon, because that's easier to measure - it's an even Tablespoon per quart spray bottle filled with water.
Thanks a million, Youbet, for bringing this to my notice!!!
Now, I can go finish the brush removal on my property. I only have about an acre left to do on my 12-acres.
-Paul, DVM, retired
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