Is there any specific evidence that they are a risk to human health?

I mean, I get the instinct that foreign-entity can't exactly be good for me, but the same instinct applied to GMOs, and as far as I know organic foods have never yielded any sort of statistically visible health impacts.

Plastics earn their keep in general by being non-reactive and 'durable', so it's not entirely shocking if they can pass through (or hang around inside) the body without engaging in a lot of biochemical activity.

I get your point that plastics are relatively inert and may not cause noticeable harm (depending on quantity?), but I think it'd be wise to be cautious. See for example https://en.wikipedia.org/wiki/Plastic#Bisphenol_A_(BPA) .

I'd also consider plastic, and their additives, to be a lot bigger and longer lasting unknown than GMOs.

Yeah, they gum up cellular workings. Kind of like how macro plastics will gum up turtle stomaches.

I have seen zero evidence that they are bad in very small quantities, but the dose can make the poison and they are out there in increasingly alarming quantities.