It’s typically sourced from natural/artificial surface bodies or pumped out of the ground.
voxic11 12 hours ago [-]
Treated waste water is very commonly used as well. Just not normally for vegetables intended to be consumed fresh. Its mostly used to grow animal feed and non-food agricultural products.
About 10 years ago, I had a 2-week-long what was most likely cryptosporidiosis episode that was frequent, vigorous liquid.
https://www.fda.gov/food/buy-store-serve-safe-food/food-irra...
> Can washing remove Cyclospora?
> No. According to the CDC, there is currently no method known to completely eliminate Cyclospora from contaminated fresh produce. [0]
Thoroughly cooking your lettuce, and other vegetables, is the only way to reliably decontaminate in this case.
If you want to eat fresh vegetables, the correct solution is separating sewage from irrigation water.
[0] https://extension.psu.edu/ongoing-cyclospora-outbreak-highli...
This sounds a bit too advanced for the nation that came up with the atom bomb and the first man on the moon and the transistor.