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Whether glyphosate causes cancer or not, there is much less doubt that it has a harmful impact on insect populations and on aquatic wildlife from runoff. Hundre

Whether glyphosate causes cancer or not, there is much less doubt that it has a harmful impact on insect populations and on aquatic wildlife from runoff. Hundreds of thousands of tons of glyphosate soaking into the ground and into the water table, reaching our rivers and lakes, year after year. How can it be safe?

colechristensen 5y ago
Glyphosphate has a pretty short persistence in the environment. It breaks down relatively quickly. It has a half-life in the environment from as little as 15 days to a couple of months. One of the significant problems with earlier pesticides and herbicides where the chemical in question would stay in the environment for decades (DDT, an insecticide, had a half life of 10-15 years and tended to accumulate in biological tissues). Glyphosphate is also not very acutely toxic. I would have to eat an entire pound of pure glyphosphate to have a 50% chance of survival. (I consume many things every day much more toxic) There are some questions about long term carcinogens but the signal there is not particularly strong. As opposed to some other, especially older agricultural chemicals, many of which got their start as actual chemical weapons used in war.
- maxerickson 5y ago
  Can you get pure glyphosate? Is that what gets spread on crops? I'm glad we are using it and not older chemicals, but unless you are actually in the habit of eating it recreationally, maybe don't use that example.
  - colechristensen 5y ago
    I believe you have to do some minor training and get a like certification, but yes, it comes in about a fifty percent concentrated solution with water. The LD50 of that solution is about a quart as far as I can determine. The point of the example is that it is not acutely toxic unless you ingest a sizable amount while dealing with concentrations only available to certified farmers. The lethal amounts come up to around how much you would apply to half an acre of cropland. Glyphosphate is also biodegradable.
  - colechristensen 5y ago
    I didn't really answer the question well. Can you get pure glyphosphate? Yes, but it requires a license. It comes in about a 50/50 mixture with water usually. It is much too difficult to distribute the pure substance in such small quantities so it is diluted with water to varying degrees (down to a few percent concentration) for safety, accuracy, and to avoid burning plants with unavoidable variations in application. A small amount of a attractant is also added so the chemical better applies to leaves and doesn't just bead up and drip off onto the soil.
    - maxerickson 5y ago
      So here's a blend that is 13% surfactant: https://labelsds.com/images/user_uploads/Roundup%20Pro%20Conc%20SDS%208-12-20.pdf https://labelsds.com/images/user_uploads/Roundup%20Pro%20Con... Apparently there's blends intended for use in water that are more or less just diluted with water, but they aren't the usual mix either. https://alligare.com/wp-content/uploads/2019/06/glyphosate-5.4-sds-v3.1.pdf https://alligare.com/wp-content/uploads/2019/06/glyphosate-5...
JamisonM 5y ago
You can say likewise about any other pesticide on that basis.. but I do wonder where the "hundreds of thousands of tonnes" comes from. My farm applies 540 grams of glyphosate per acre on our soybean crop each season.. if that is applied to every acre of farmland in the USA that would be 500mt of glyphosate. So you believe that a majority of the acres in the USA have at least 540g/ac applied and that a majority of that glyphosate is not metabolized by plants but is mobile in runoff? I would be extremely interested in the research that validates that because it is not consistent with my experience.
- efficax 5y ago
  https://www.epa.gov/sites/default/files/2019-04/documents/glyphosate-response-comments-usage-benefits-final.pdf https://www.epa.gov/sites/default/files/2019-04/documents/gl... 280 million pounds of glyphosate used per year
  - JamisonM 5y ago
    That's 127 thousand metric tonnes, right?
    - efficax 5y ago
      Roughly, and that's only the united states.
sampo 5y ago
> Whether glyphosate causes cancer or not, there is much less doubt that it has a harmful impact on insect populations and on aquatic wildlife from runoff. It's actually not glyphosate that can be harmful to aquatic animals. It's the accompanying surfactants, added to help glyphosate to enter the plants. You put too much of any kind of surfactant (basically, a soap. A chemical that lowers the surface tension of water) to a small volume of water, and it will be harmful to aquatic life.

colechristensen 5y ago

Glyphosphate has a pretty short persistence in the environment. It breaks down relatively quickly. It has a half-life in the environment from as little as 15 days to a couple of months. One of the significant problems with earlier pesticides and herbicides where the chemical in question would stay in the environment for decades (DDT, an insecticide, had a half life of 10-15 years and tended to accumulate in biological tissues). Glyphosphate is also not very acutely toxic. I would have to eat an entire pound of pure glyphosphate to have a 50% chance of survival. (I consume many things every day much more toxic) There are some questions about long term carcinogens but the signal there is not particularly strong. As opposed to some other, especially older agricultural chemicals, many of which got their start as actual chemical weapons used in war.

maxerickson 5y ago
Can you get pure glyphosate? Is that what gets spread on crops? I'm glad we are using it and not older chemicals, but unless you are actually in the habit of eating it recreationally, maybe don't use that example.
- colechristensen 5y ago
  I believe you have to do some minor training and get a like certification, but yes, it comes in about a fifty percent concentrated solution with water. The LD50 of that solution is about a quart as far as I can determine. The point of the example is that it is not acutely toxic unless you ingest a sizable amount while dealing with concentrations only available to certified farmers. The lethal amounts come up to around how much you would apply to half an acre of cropland. Glyphosphate is also biodegradable.
- colechristensen 5y ago
  I didn't really answer the question well. Can you get pure glyphosphate? Yes, but it requires a license. It comes in about a 50/50 mixture with water usually. It is much too difficult to distribute the pure substance in such small quantities so it is diluted with water to varying degrees (down to a few percent concentration) for safety, accuracy, and to avoid burning plants with unavoidable variations in application. A small amount of a attractant is also added so the chemical better applies to leaves and doesn't just bead up and drip off onto the soil.
  - maxerickson 5y ago
    So here's a blend that is 13% surfactant: https://labelsds.com/images/user_uploads/Roundup%20Pro%20Conc%20SDS%208-12-20.pdf https://labelsds.com/images/user_uploads/Roundup%20Pro%20Con... Apparently there's blends intended for use in water that are more or less just diluted with water, but they aren't the usual mix either. https://alligare.com/wp-content/uploads/2019/06/glyphosate-5.4-sds-v3.1.pdf https://alligare.com/wp-content/uploads/2019/06/glyphosate-5...

JamisonM 5y ago

You can say likewise about any other pesticide on that basis.. but I do wonder where the "hundreds of thousands of tonnes" comes from. My farm applies 540 grams of glyphosate per acre on our soybean crop each season.. if that is applied to every acre of farmland in the USA that would be 500mt of glyphosate. So you believe that a majority of the acres in the USA have at least 540g/ac applied and that a majority of that glyphosate is not metabolized by plants but is mobile in runoff? I would be extremely interested in the research that validates that because it is not consistent with my experience.

efficax 5y ago
https://www.epa.gov/sites/default/files/2019-04/documents/glyphosate-response-comments-usage-benefits-final.pdf https://www.epa.gov/sites/default/files/2019-04/documents/gl... 280 million pounds of glyphosate used per year
- JamisonM 5y ago
  That's 127 thousand metric tonnes, right?
  - efficax 5y ago
    Roughly, and that's only the united states.

sampo 5y ago

> Whether glyphosate causes cancer or not, there is much less doubt that it has a harmful impact on insect populations and on aquatic wildlife from runoff. It's actually not glyphosate that can be harmful to aquatic animals. It's the accompanying surfactants, added to help glyphosate to enter the plants. You put too much of any kind of surfactant (basically, a soap. A chemical that lowers the surface tension of water) to a small volume of water, and it will be harmful to aquatic life.