Ask Lemmy

When it comes to toxicity to water life you have to think of the dose. If a rose bush sheds a few petals and it falls to a lake will anything bad happen to the life in the lake? No absolutely not. That happens naturally. The petals will quickly decompose and become nutrients that will feed the ecosystem in the lake. However if someone would drop a dozen truckloads of petals in the lake then that would be way too much organic matter for the ecosystem in the lake to handle. But some shower gel is never gonna come close to that. It's more gonna be on the magnitude of the bush shedding some petals naturally in the lake. Same with the essential oil. Concentrated essential oil can be quite toxic to both human and other life. But in dilution it's something else completely. A natural rose bush will evaporate tonnes of essential oil straight into the air during its whole life time and nothing takes damage from it. That's why you can smell a rose plant when standing next to it. Dilution is sometimes actually the solution. A single drop of essential oil into the sewer drain once a day would not cause any negative effect at all when it's diluted with tonnes of shower, toilet, sink and even industrial waste water. Diluted it won't damage any life, especially since essential oils are biodegradable.

Also think what else gets down into the sewer. In most places your toilet and your shower are connected to the same system. The poop you put in your toilet is multiple magnitudes worse than anything you could use while showering. If your waste water treatment plant can't even treat the poo then you have bigger problems then anything you could put into your shower gel. If it's good enough to treat poo however then it's good enough to treat whatever's in your shower gel.