promotion image of download ymail app

How do pesticides kill insects?

When I spray pesticide on a roach or whatever, 5 seconds after contact it stops moving and appears to be dead. It appears to be more than just poisonous, it almost instantly kills/paralyzes them.

How does the pesticide work so fast, what does it do to the insect? What does the insect feel when sprayed on?

From what I have read the effect it has on insects is similiar to the effect nerve gas (chemical weapons) have on humans, but humans dont instantly die from nerve gas, they die slowly, so why is pesticide so devastating to the insect that it causes almost immediate death?

7 Answers

  • 1 decade ago
    Favorite Answer

    Insects do not have closed circulatory systems, as in, they do not have blood vessels and their organs are constantly surrounded by their blood. Therefore, poison does not have to travel very far in order to reach the nervous system of the insect, which most insecticides target.

    Insecticides kill the nerve cells of insects by forcing open the sodium channels of the cells, this rapidly kills the cell.

    As for the second question, Insects do not have the nerve cells that cause pain (nocicepters), so I don't think they feel pain in itself.

    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    A lot of common insecticides are acetylcholinesterase inhibitors, meaning they breakdown chemicals important in the nerves. From what I understand, an insect's body releases a chemical that makes their exoskeleton (essentially their skin as far as we're concerned) expand so that they essentially inhale air through little holes. That is how they inhale. There is another chemical that is an enzyme (acetylcholinesterase) that breaks down that chemical and allows them to "relax" and lets them exhale essentially. What happens with some pesticides is that they destroy the acetylcholinesterase so that the insect can't exhale and so they essentially die because they can't breathe, and they are paralyzed. It's kinda icky if you think about it...

    One reason we aren't as affected is that we are so much bigger that we need a larger dose. The insect is very small and we are pretty dang big compared to those insects, so can you imagine being completely drenched in pesticide? That's what would have to happen.

    This is quite a good article about the whole system...

    This is a fairly technical website about acetylcholinesterase inhibitors, but it's interesting and tells you why humans aren't affected as much with some pesticides...

    I'm not sure how technical you are, so hopefully this helps you to understand!

    • that essential answer essentially helped essentialize me essentially.

    • Commenter avatarLogin to reply the answers
  • Anonymous
    5 years ago

    This Site Might Help You.


    How do pesticides kill insects?

    When I spray pesticide on a roach or whatever, 5 seconds after contact it stops moving and appears to be dead. It appears to be more than just poisonous, it almost instantly kills/paralyzes them.

    How does the pesticide work so fast, what does it do to the insect? What does the insect feel when...

    Source(s): pesticides kill insects:
    • Commenter avatarLogin to reply the answers
  • asia
    Lv 4
    4 years ago

    How Do Pesticides Work

    • Commenter avatarLogin to reply the answers
  • How do you think about the answers? You can sign in to vote the answer.
  • 3 years ago

    What Do Pesticides Do

    • Commenter avatarLogin to reply the answers
  • 4 years ago

    For the best answers, search on this site

    Yes I do have an issue with it. I eat solely organic food (I have been vegetarian all my life, vegan 5 years and organic 3 years) and only buy organic textiles (or secondhand) and toiletries etc. Yes a few (7, some are for fungal disease though, not insects) organic pesticides are allowed, but in the UK at least they have to get special permission each time, and they have to explain how they will avoid having to use them again (i.e. improve their growing system). It still kills far less animals than using them all the time. It's not only insects pesticides kill, but also animals which eat the insects - the concentration of toxins increases at each stage of the food chain so some birds of prey are almost extinct because of this. DDT (which was banned many years ago in most countries) is still found in penguins - so it is still doing damage even now. And of course pesticides are made by unethical companies (e.g. AstraZeneca) which test them and their other products on animals. Some additives in non-organic food are tested on animals (it's as bad as using animal-tested toiletries, surely?), and non-organic GM food may even contain animal genes, e.g. they have put fish 'anti-freeze' genes in strawberries. As someone mentioned it is bad for the farmers' health too. There are many farmers who have died of cancer from pesticide exposure. This is a problem particularly in developing countries where they can't afford protective clothing when spraying. [NB: some organic cotton is fair-trade when it's made from the cotton bolls into material, but the actual end result - clothes - may still be made in sweatshops, so watch out!] And pesticide run-off from fields contaminates rivers and kills aquatic animals and those which drink the water. Have you seen pictures of the dead zone in the Gulf of Mexico? That's due to fertiliser and manure run-off! By using artificial fertilisers we are also depleting our fertile topsoil - it should be 6' deep on average but it is 6" - as it's so shallow and we are chopping down more trees we are losing even more as it gets washed away by rainfall. It's a vicious cycle as it means we need more fertilisers to get the same yield - we should be planting green manures in rotation instead to improve the soil. Organic farming is more sustainable in general - for example organic palm oil is grown without destroying the forests where orangutans live, and you won't find much slash-and-burn in the Amazon for organic agriculture! [Some mostly organic products can contain non-organic soya lecithin, most of which is produced by Cargill, a terrible company - look up their record! So look out for that.] Organic farming still uses some animal inputs (e.g. manure, unless you find a stock-free organic farm!), but it is FAR more ethical than non-organic food. You could also grow some of your own food, in a windowbox, garden or allotment (diluted human urine is a good free fertiliser, and you can compost your food waste to reuse on the soil). It doesn't have to be expensive - my partner and I have a total income of £16,000 (well below average) and we feed ourselves and a dog and 4 guinea pigs all on vegan and organic food. Clothes/linen are more expensive when organic but if you only buy what you really need it's affordable. Or get secondhand if you really can't do it. We get a vegetable box (all is British, some is from local allotments and the rest is from farmers in our region) for £12 a week, and the rest of our food comes from a wholefood wholesaler - we buy e.g. a 25kg sack of rice twice a year for £20. I think the USDA organic standards are more lax than the UK ones, so watch out - even if it's labelled organic check exactly how much of the ingredients are! By the way, where did you get the info about the more insects killed per kg veg than honey? I am trying to convince my vegan colleagues to go organic, so it would be useful to show them that! Some of them eat quite a bit organic, but not when they go out (it's like not being vegan when you're out - how pointless!) etc so I never get to eat at meals, I just go for the company. Anyway, I don't think non-organic products are vegan, so I am very glad to find someone who agrees! And to all those who are saying 'but X action kills animals too' - it doesn't matter - the point of being vegan is surely to reduce harm as far as possible. So if eating organic saves a few thousand or million extra animals, why wouldn't you do it? That doesn't have any impact on something completely unrelated such as stepping on a worm accidentally! What you are saying is akin to saying: 'dairy kills cows so don't bother going vegetarian', or 'pesticides kill insects so there's no point being vegan' - there's no reason not to take the next step just because the future ones still cause damage too - each stage causes less and less damage so the further you go the better. Even if animals are still killed by tractors in the field (a good reason to grow your own or buy from small growers, or even forage!) in organic production that's the same number which would have died in non-organic production anyway, but you aren't killing all the others with chemicals *as well*.

    • Commenter avatarLogin to reply the answers
  • Anonymous
    1 decade ago

    You learn something everyday.

    Thanks Blaze

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.