A few years ago I had a septic system pumped. I got to talking with the guy, and he commented that he’d been at some homes where the tanks were a real mess—things didn’t break down. He said they were usually occupied by elderly people taking a lot of medications, and that the medications seemed to kill the normally active bacteria, causing the problem.
I thought it was interesting, considering that medications are measured in fractions of grams, and the septic tank is roughly 1500 to 2000 gallons, plus overflow.
Two professors at a local college found prescription drugs in the local river. Not all of a drug is metabolized by the body before it’s excreted.
I have a rental income property with a septic tank, it’s amazing what people flush. They have no idea some measure of it ends up in the tap water.
I never had sewer until I moved here. Upkeep of the lines is pricey. I NEVER had a problem with a septic system....I wish the law allowed that option.
Another huge source of contamination that gets into rivers and lakes is the chemicals that people put on their lawns. There isn't even a reason for that. A well-chosen grass for the environment and soil conditions does not need fertilizers or plant foods.
When medicines are dosed, one of the factors considered is how much of the medicines the body can absorb before the rest is excreted as waste.
In a septic tank, the antibiotics aren't going anywhere and can pose as more than the required quantity to kill off the microbes, even in large containers.