It remains underexplored, but there's many papers released and many studies being done to try and confirm. A big one is hormonal; BPA is a xenoestrogen, emulating the effects of estrogen on human bodies, with studies showing links between it and reduced fertility. There's been ~19000 studies on it so far, most since the 2000s (https://pubmed.ncbi.nlm.nih.gov/?term=bisphenol+a).
Jump-off points:
https://en.wikipedia.org/wiki/Microplastics_and_human_health...