What's interesting about this study is that ticks were reduced by 50% with untreated woodchips (no pesticides!)

I mean, yeah. Ticks live in grasses not on the ground. If you walk on bare trail and don’t brush on grass or other plants your chance of a tick is much lower

They measured density, not the probability of getting one.

Do you think those are maybe correlated? The measured density on the path

It's only hazardous when wet. I spray my clothes and then let them dry on the clothesline.

Don't sweat?

I have a peculiar medical condition which is that I don't sweat... because I had suffered what I would describe as an overdose of adrenaline in the Falkland's War.

Perhaps a nice relaxing week at my private Caribbean island will help cure you?

Do you have air conditioning?

That doesn't matter as long as it has dried from the initial application.

Your first link talks about occupational use. Most folks aren't going to have that sort of exposure. A lot of things are definitely a hazard when you work with them often, but doesn't carry over into the general population whose exposure is very low.

Your second link speaks of animal studies, using 34mg/kg of body weight in very young animals (rats) between 6 and 21 days old. Animal studies are valuable, but it doesn't mean you carry the same risk of rats. I'm not sure most folks are going to get that much exposure while walking along trails - for me, personally, it would take 1870mg of repeated exposure. I understand that it would take less exposure for children, but an average newborn is around 3kg and the newborns aren't walking along trails - and in most circumstances, neither are their parents. Especially the mother, who just recently gave birth.

It isn't that I'm saying that pesticide exposure is always healthy or anything, but the type of study and the doses are important to give perspective.

That's easy - lyme disease. If you read the studies you linked, it even shows this very clearly.

The first study is talking about constant occupational exposure. By people not wearing basic PPE, over the course of many many years. It's like taking a shower in permethrin every day for 30 minutes. You can pretty much substitute lots of every day things that get absorbed by skin for "permethrin" here and it would cause some very serious symptoms.

The second study used 34mg/kg of permethrin. That is an insane amount, and one that you could not even likely get without intentional ingestion of concentrated powder form.

If you weight 150lbs, that is 2300mg. So a huge horse sized pill of permethrin, every day, will cause issues.

Shocking.

2300mg a day of most substances will cause issues.

Hell, 2300mg a day of most things will cause serious issues faster than permethrin

2300mg of vitamin b3 would destroy your liver very quickly (weeks/months).

2300mg of vitamin b6 would cause permanent nerve damage very quickly (weeks/months)

etc

The reason we don't classify all pesticides as equally dangerous is because they are not all equally dangerous.

Lumping them all together and painting them with a single brush is as unhelpful here as it is when it is done in any other context.

Permethrin is just a synthetic version of pyrethrin, which is extracted from chrysanthemums.

It is probably one of the least harmful substances you will ever be around.

Lyme disease is easily a much greater threat to people than exposure to permethrin and derivatives while hiking.

The exposure to wood dust and other small particles from disturbing the wood chips is probably a greater threat than the permethrin.

Do you mean people should wear PPE when in tick infested areas?

I generally wear pants, full sleeve shirts, long socks etc whenever I go hiking but have still found ticks on me later on. Or do you mean something else by PPE?

No, i mean not wearing PPE while spraying pesticides. Most of them wear gloves. Maybe long sleeve shirt/pants. Respirator/masks are very rare.

Permethrin is not well absorbed through skin anyway (0.5-1%). But easily absorbed by breathing it.

Lyme disease is not the only tick disease.

There's alpha gal (red meat allergy ) and also ascending paralysis. And more.