Surfactants are just soap, and their mechanism of action is mechanical: they will physically remove a membrane, or clog a pore, or whatever.
This is in contrast to insecticides, whose mechanism of action is toxological: they can act on a bug's nervous system.
One is soap, the other is toxin.
What this means is that soaps (surfactants) are much, much safer for the environment because they can be effectively diluted, unlike toxins which can be lethal to intersects even in minute amounts.
So yeah, if some of the soap gets on a bumblebee it might die, but you're not going to get a "one drop of this got in a hive and now everything is dead" effect.
Just because something is a "soap" doesn't mean it isn't toxic or damaging. [1]
Mosquito control has been moving towards using bacteria [2] which is safe and effective at killing mosquito larva. I'd actually be pretty concerned about putting a surfactants in the water. There's no telling how that will affect local fauna or non-targeted creatures.
The advantage of pesticides is that it can be selective poison. Killing say all insects, but no mammals. Things like soup aren’t selective. They’ll kill not just insects but also fish and random other things
This is the same reason I far prefer to disinfect with bleach rather than antibacterial cleaners - the anti bacterial properties last for ages and are messing up the sewage plants here in the UK. Can't imagine what they are doing to our water ways here (sewage ends up in our streams and lakes with alarming regularity).
Bleach on the other hand loses effectiveness quickly.
Generally, "antibacterial" cleaners are full of antibiotics. The ones used are usually those that are poorly absorbed by the human GI tract, and thus of limited potential medical use in humans. But since the mechanisms of action aren't unique, they too promote antibiotic resistance.
Why would they be? They are anti biotics, not antibiotics. There is no need to selectively kill bacteria. You can go all-in and kill literally everything.
"Kill everything" generally means something like bleach, which is very effective but not so great for your hands.
Anyway, I'm not saying that's the way it should be, just the way it is. Selecting for compounds that don't kill eukaryotes is one of the ways you get your product on the market.
Likewise, but don't forget that bacteria have loads of uses and niches in the environment, so killing 'good bacteria' in a stream or environment (or in your body) can have greater impacts than it might first seem.
True but pretty funny to see the different angles on the same thing in articles a couple years ago talking about how roundup was killing insects, not because of the glyphosate, but because of surfactants that were in there to help make better contact with the leaves. As you say, it is not a toxin, but can still have negative impact on other species.
there's been at least two studies done on the "inactive" vs "active" ingredients in roundup, and it was found that glyphosate by itself is less effective a pesticide than the inactive ingredients.
I still chuckle every time i think about it, in a defeated, consigned to doom sort of way.
What's to say that (a) the mosquitos won't develop a resistance to the surfactants, as they do to conventional insecticides, and (b) the surfactants won't be as damaging to the environment as other insecticides?
If these surfactants cause harm to other insects, it would be safe to classify them as insecticides themselves. Then you've just got a new type of insecticide, and need to demonstrate (a) precision, (b) recall, and (c) cost-effectiveness vs. all the other existing insecticides.
There’s lots of chemicals that are extremely lethal to pests with apparently limited ability to develop resistance. There’re no bleach resistant bacteria, for example, and no fire-resistant moths.
Surfactants attack the waxy layer that insects use to breathe, they’ve been very effective at killing them for a long time. The classic fruit fly trap of soap in vinegar uses this effect.
There’s a lot of soaps with a long history of being used in the environment, but like they do have a mechanical effect. Probably not great to douse plants with them.
The biggest challenge I see is they’re not really persistent like permethrin — you need to spray the mosquitoes with the surfactant. That limits application as people will complain about like a fogger truck that makes them a little soapy.
Surfactants can drown bugs as well, sink any bug that walks on water, and remove the protective mucus from fish scales, which is often a problem with tank fish.
Extremophiles is a fascinating classification of organisms. Basically think almost any environment where you wouldn't survive and there is something living there... Ofc, in reasonable limits like not plasma, but at extremes for sure.
> What's to say that (a) the mosquitos won't develop a resistance to the surfactants, as they do to conventional insecticides
You can't really "develop a resistance" to something that is fundamental to your genetic identity. That's like saying "what if humans developed a resistance to being dunked in vats of acid?"
FWIW alot of surfactants used on the consumer market today are derived from petroleum and may even be harmful to the environment . Calling it just soap is sort of funny.
An aqueous surfactant solution will suffocate any insect to which it's applied, not just mosquitoes. This has long been well known and there is nothing novel here, although I'm sure they'll find some excuse for a patent application.
There is a wide range of degrees to which surfactants persist in the environment. AIUI, good old SLS degrades quite quickly. On the opposite end of the spectrum, PFOS and PFOA are extremely persistent.
A homemade mix of dish soap and water kills all manner of insects and other arthropods. None of this is new.
I found this out the hard way. When my sister and I were young, there was a carnival nearby, and they had some sort of ball toss game where you could win a goldfish. So we both won our goldfish and took them home in the tiny globe aquariums.
I can't remember what happened to my fish, but I think it was out of the picture quickly. My sister's fish was named "Goldie" and, having a scientific mind, I was curious what would happen to the surface tension of the water in there if I dropped a fingernail of soap into it. Well, Goldie immediately said "feeding time!" and gulped down the soap. I snuck away, and eventually heard my sister cry "Goldie's Dead?!" from our room, and I think I eventually had to 'fess up.
IPA (isopropyl alcohol, rubbing alcohol) kills nearly every insect, too. It doesn't kill centipedes, though - at all. It just makes them angry. (nearly) Anything else a square hit with a spray bottle or spritzer is enough to cause death, within minutes if not seconds.
I question how safe it actually is - I'd assume it could impact a lot of other biological processes in the environment. They can change the way other compounds in the environment are absorbed by plant and animal tissue. At the same time, massive amounts of surfactants are already used with herbicides like roundup, so we do have an idea of how it might impact things - but that's in an agricultural setting.
Would not recommend adding anything to water streams. Water with surfactants could cause more permanently contaminated water. Water is remarkably clean despite all the pollutants and garbage and dirt out there because particulates and contaminants deposit and fall out of solution relatively quickly. Surfactants could slow that down.
As others point out, this is (a) not susceptible to developing resistance, (b) applicable to lots of species besides mosquitoes, and (c) feels soapy if it lands on you.
For (b) and (c), it probably also has some effect on plants it lands on.
I learned recently from a bee keeping youtuber that the recommended method for euthanizing a problematic hive is just dumping in a bunch of soapy water which kills them for the same reason.
I’ve eradicated 2 nests of european wasps here in Australia by dumping a pretty strong solution of dish soap and water down the nest.
Carefully, at night, with red light just to be sure.
They are the most aggressive pests I’ve ever had the misfortune to run across, if you kill one, you get attacked instantly, and they will chase you, if it was a large active nest, I’d be very cautious.
He couldn't even go in his yard without being swarmed. He was genuinely concerned for his and his families safety. His other hives are much more docile.
People have put a small layer of oil over stagnant water for a long time. It's environmentally pretty innocuous (just use a plant oil) and stops them from breeding.
Probably also detrimental to other insects, I hope not but probably. Insects are a key element in the biosphere ad without them we would be pretty screwed.
I find this sort of thing pretty silly (permethrins are reasonable pesticides, IMHO), but this is not the hard part.
Misting systems are already used to control mosquitoes in yards if that's your goal.
Misting surfactant instead of permethrin is not that difficult.
It isn't going to be a soapy mess.
I make my own ultrasonic cleaning solutions, and mix triton-x (a super-common surfactant) into things. At a much higher concentration than they are talking about here (1%). It is not really that bubbly at this concentration.
They are using DOSS and a few others.
The units they use (millimolars) are annoying to convert, but assuming i'm doing the math right, you are talking about about 1.5grams per liter of surfactant.
(DOSS is 444.5583grams/mol. So we have 444.5583grams/mol * 3millimol = 1.3336749 g per liter)
This will not make a soapy mess with any surfactant they are using.
Thanks. What happens to it over time though, won't it just build up like crazy in the place you spray it continuously? Or it dries up and blows away or breaks up in the sun or something?
Well if we have a permanent sprinkler dispensing some kind of detergent, how will it _not_ build up?
You have to physically hit the bugs with it, so it has to be going all the time or it has to already have covered whatever the bugs will touch. Either way it's just a mess, right?
Related: "Mosquitoes survive raindrop collisions by virtue of their low mass" by Dickerson et al. [1]; see also MITTechTV's "How mosquitoes fly in rain" [2].
As a pet owner, rather than using insecticides, I use a couple gallons of hot water mixed with washing-up liquid to eliminate fire ant nests in my yard.
The hot soapy water washes away the structue of the nest, and quickly kills the inhabitants, whilst not damaging my lawn, or having slow acting insecticides hurting my animals and getting into the wider food chain.
Mosquitos are pretty common in India and kills enough people, though roughly 8 times less than road accidents. Malaria is no longer very deadly but Dengue treatment indeed is pretty costly. Sometimes I feel that dengue cases are higher in cities than in villages.
Mosquitos are most active at dawn and dusk when people are usually out farming or just hanging out. Mosquito nets and mosquito repellent works well indoor.
Either you wipe out mosquitos species that cause malaria and dengue, or create vaccines and better drugs. Anything less than that is not going to be much effective. Personally I am against wiping out any species. The planet doesnt belong to us only.
Due to the coronavirus i got into making my own IPA sanitizer spray with mint extract (careful, it can kill you, it's basically concentrated aspirin). 65-70% IPA by volume and 30-40 droplets of mint extract. Since i only sanitize my hands once or twice a day anymore i mostly use the spray for flying insects and roaches that manage to get past my cats.
I forget where i heard/read it - because of the information i was able to find back when, i treat concentrated mint oil the same as i did 10% nicotine.
To the best of my recollection, the "aspirin" part was comparing what a high dosage/overdose was like. I apologize for making the inference that it was "like" aspirin.
All i can find now is that menthol is potentially the dangerous part in concentrated mint oils - however i don't remember menthol being mentioned. I'm also used to claims of "misremembering" details from a half decade or more ago, and have since began screenshotting webpages with potentially controversial information, as well as saving and organizing all pdfs for studies i read, that are linked from news articles or social media. Hopefully situations like this one occur less frequently!
This is in contrast to insecticides, whose mechanism of action is toxological: they can act on a bug's nervous system.
One is soap, the other is toxin.
What this means is that soaps (surfactants) are much, much safer for the environment because they can be effectively diluted, unlike toxins which can be lethal to intersects even in minute amounts.
So yeah, if some of the soap gets on a bumblebee it might die, but you're not going to get a "one drop of this got in a hive and now everything is dead" effect.