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Comment by edf13 | Hacker News Reader

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"What we eat and what we excrete goes into the Puget Sound," Jennifer Lanksbury, a biologist at the Washington Department of Fish and Wildlife, told CBS News affiliate KIRO.

...so enough crap going into the water from the local population to be picked up in the Mussel samples... Crazy!

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Waste water treatment doesn't remove drugs, so they make it out into the water, and the filter feeders pick it up.

I’m surprised the chemicals don’t quickly break down in the salty sea water. Do ocean environments affect half-life of pharmaceuticals differently?

Water shields double bonds from UV light preventing them from breaking down. For examples of this look no further than PCBs (polychorinated biphenyls, not circuit boards)

Waste water can be tested to give an idea of population drug usage.

https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&object...

A fun fact that a friend of mine shared is that there are trace amounts of sucralose in our water supply. It turns out that inert sweeteners that are not digested just get excreted, and since it's not a molecule found in nature they don't break down quickly.

Molecules being found in nature, or not, has nothing to do with the speed they decompose. Many unnatural compounds are similar enough to natural ones for microbes and enzymes to decompose them efficiently. And many compounds, like glass, aren't likely to decompose even though they are plentiful in the environment.

I'd be surprised if it has nothing to do with it, in that I'd expect compounds that are common in an environment to be much more likely to have organisms evolved to exploit them when possible.

For some reason plexiglass/perspex is curiously compatible with organic tissue, more so than glass. So a fighter pilot with shards of plexiglass in his/her eyes will have a better prognosis. Naturalness isn't always the last word.

It's also one of the ways for detecting the amount of pee in a pool - if people had a diet Coke before they peed then it can easily be detected. (Urea can be released via sweat I believe - so that's not a good signal)

I think that urea reacts fairly quickly with Chlorine to form various chloramines, which, in turn, degrade to N2 and chloride.

Urea is also an ingredient in a lot of lotions and other skin products.

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