I know the bug season is almost over in the BW, but I just got back from a 9 day trip on the Sutton river that empties into Hudson's Bay, and the bugs, especially blackflies, were FIERCE! It's the first time I have ever actually encountered clouds of blacflies. We had to eat in a screened tent enclosure most nights.

Anyway, about 3 years ago I started spraying our tents with permethrin. Initially I sprayed only the interior of the tents. We noticed that it totally eliminated the need for mosquito coils in the tent, and within a few minutes, any bugs that got into the tent were quickly incapacitated, and shortly thereafter, dead. Permethrin (called Permanone in the spray cans) is both an insect repellant and an insecticide, often used for termite control. During our July BW trip this year I noticed that the bugs generally avoided our tents, and I found that my buddy had sprayed not only the inside, but the outside and the fly. The effect was amazing. In the far north last week my permethrin treated tent was essentially bug free, and the other tents had the problems you would expect. Whatever bugs got into my tent were soon dead on the floor. The only negative was the need to shake out the dead blackflies from the tent every morning. One night I even inadvertently slept with about two feet of the door zipper open with no problems! Not a single in-tent bug bite for the trip.

Because of the expense of the spray cans, a few years ago we began using the concentrated agricultural product (36%) which we dilute down to .05%. You can buy it at most Co-Op stores - get the 36% not the 10% product. We use it both for soaking our clothes and spraying the tents. A quart will make about 20 gal of solution, so it lasts for
many years.

Some people on another board have raised safety concerns about the use of permethrin. I will simply say that I researched this topic fairly thoroughly before I began using it. As a physician I am sensitive to these issues. Permethrin does have toxicity to fish, and there are reports that cats are very sensitive -- despite this, permethrin is commonly used as a flea treatmtnet for both dogs and cats. It is also used on chickens and poultry. It is used as an insecticide on cattle and livestock, and has even been used as a treatment for human lice. There is no credible evidence that it is toxic to humans, nor is there actual evidence that it is a carcinogen. In liquid form it can cause skin irritation, but this is not an issue once the product has dried. I would suggest that you not pour the concentrated product on your skin. It is the same chemical used in "Buz-Off" clothing. I am personally convinced that it is quite safe.

Those of you who hate bugs should try it.

My daughter and I went in May and she counted nearly 30 ticks on her over our five days. Her clothes were not treated.

I had two. My clothes were treated. And one of those ticks was on a shirt not treated with permethrin.

I still have health concerns seeing as PCB's used to be touted as safe and risk-free before we learned more about them. And DDT, and asbestos, and... and... and....

Permethrin is approved for commercial use in many agricultural applications such as processing plants, dairy facilities, barns, etc. The stuff is safe if used per label directions to be sprayed on livestock and dogs (not cats). A 4 oz bottle of 40% (Y-Tex brand) that will make gallons / years worth of spray is 18.99 at your local farm store. This is a commercial product that may or may not require a pesticide applicators license to purchase depending on your state. Any farm store will have this product. Follow the label directions. One negative of the ag version is the smell. Has a chemical smell vs. the outdoor products which have very little smell. Y-Tex

Yes, the Ag version does have a bit of a chemical smell, but I find that once it is dry the smell is barely detectable. We have never noted it to be a problem on our clothes. In our area, a quart (32oz) of 36% solution costs about $25- $30. To make a 0.05% solution (same as in the Permanone spray cans) requires about 1.6 oz. per gallon.

Question - if you should not touch the product when wet.... what about wading in the water in clothes that have been treated previously? Just asking since many people wet foot.

I also (without thinking) went in for a swim this spring with all my treated clothes on. Just was not thinking. Next day and for three days after, I had to urinate frequently (every one to two hours). Gave me pause to think. Could not find urination as a symptom of exposure/poisoning online. Could have been due to all the ibuprofin I was taking for paddling and portaging??? It's tough getting old.

I think the problem with making up one's own permethrin solutions for treating clothes or tents is dealing with the excess or waste solution. It can't be dumped down the drain or storm sewer as that will ultimately end up in the local water supply. Yes, it will be diluted, but IT IS VERY TOXIC TO to fish and aquatic invertebrates (at nanogram to microgram per liter concentrations, i.e. extremely dilute).

That said, it is used by many municipalities to control mosquitoes who are no doubt spraying ponds and creeks--and it's no wonder that there are no fish in some of these bodies. It is also used by just about every soldier operating in the field in Iraq and Afghanistan.

Like most chemicals, it is a game of trade-offs; the benefits do not come without their hazards. Permethrin may have low human toxicity, but the same can't be said for fish. The advantage of using a prepared spray is that there is little to no excess or waste to deal with.

This is Bayer's (a permethrin manufacturer) hazard statement and instructions for disposal off their Permanone 3166 MSDS (material safety data sheet). Permanone MSDS

Environmental Hazards
This pesticide is [b]extremely toxic to fish and aquatic invertebrates. Runoff from treated areas or deposition of spray droplets into a body
of water may be hazardous to fish and aquatic invertebrates.[/b] Do not apply over bodies of water (lakes, rivers, permanent streams,
natural ponds, commercial fish ponds, swamps, marshes or estuaries), except when necessary to target areas where adult mosquitoes
are present, and weather conditions will facilitate movement of applied material away from the water in order to minimize incidental
deposition into the water body. Do not contaminate water when disposing of equipment wash waters.

This pesticide is highly toxic to bees exposed to direct treatment on blooming crops or weeds. Do not apply this product or allow drift
when bees are actively visiting the treatment area, except when applications are made to prevent or control a threat to public and/or
animal health determined by a state, tribal or local health or vector control agency on the basis of documented evidence of disease
causing agents in vector mosquitoes, or the occurrence of mosquito-borne disease in animal or human populations, or if specifically
approved by the state or tribe during a natural disaster recovery effort. Applications should be timed to provide the maximum possible
interval between treatment and the next period of bee activity.

Do not contaminate water, food or feed by storage or disposal.
PESTICIDE STORAGE AND SPILL PROCEDURES: Store upright at room temperature. Avoid exposure to extreme
temperatures. In case of spill or leakage, soak up with an absorbent material such as sand, sawdust, earth, fuller’s earth,
etc. Dispose of with chemical waste.
Pesticide Disposal: Wastes resulting from the use of this product may be disposed of on site or at an approved waste
disposal facility.
CONTAINER DISPOSAL: Metal Containers - Triple rinse or equivalent.
Then offer for recycling or reconditioning, or puncture and dispose of in a sanitary landfill, or by other procedures
approved by State and local authorities.
Plastic Containers - Triple rinse or equivalent. Then offer for recycling or reconditioning, or puncture and dispose of in a
sanitary landfill, or by incineration, or if allowed by state and local authorities, by burning. If burned stay out of smoke.
Then dispose of in a sanitary landfill or by other approved state and local procedures.
CONTAINER DISPOSAL FOR RETURNABLE CONTAINERS: Replace the dry disconnect cap if applicable, and seal all
openings which have been opened during use. Return empty container to a collection site designated by Bayer
Environmental Science. If container has been damaged and cannot be returned according to the recommended
procedures, contact Bayer Environmental Science Customer Service Center at 800-843-1702.
RETURNABLE/REFILLABLE SEALED CONTAINER: Do not rinse container. Do not empty remaining formulated product.
Do not break seals. Return intact to point of purchase.

I sprayed some around the doors/thresholds/zippers of my tent with good results. Replied accordingly to a thread awhile back. Someone posted asking me what it did to the waterproofing. I don't know that it did the coating any good; but it doesn't leak (yet) and I feel more confident about bugs IN the tent.

Why would one spray insect repellent on a tent?

Is the mesh not keeping some really tiny bitting critters out?

To date I've not had a problem with critters getting through my tent's mesh, though some sometimes sneak in while I'm entering & exiting. Usually that's not a big deal.

I'd be cautious about spraying chemicals on the waterproofing layer without KNOWING what that will do to it over the long run. You might contact the manufacturer and ask them before you start spraying.

Personally I wouldn't want to sleep in the fumes.

I do not spray to keep insects out of a closed tent. I spray to take care of any insects that do get into the tent, and to discourage them from wanting to come in in the first place. It works quite well. When there are insects buzzing all around the tent, I don't have to worry about any of them coming in when I have to get up at night to answer nature's call. If this has never been a problem for you then you are lucky, and shouldn't use it.

As for disposing of the excess, you can spray it on the lawn -- works good on chiggers and termites. Or, you can do what I do, which is to put it in a container and use it next time I need it.

Also, this is the forth year that I have used it, and so far the urethane waterproofing layer on the tent is just fine.

Canoekev: "spray it on the lawn" is probably the best thing one can do as long as your long is not adjacent to a creek or other fish containing body of water.

I don't see the active ingredient in these sprays having any great effect on the waterproofing especially if the permethrin is applied from a waterbased solution. Just be sure to let the fly dry completely before you use it. Same for the aerosol sprays which may have more solvent in them.