phthalates, like flax seeds and soybeans, are probably endocrine disruptors in humans. they're oils, not solid plastics; you add them to pvc to transform it from a rigid, brittle substance like those white sewer pipes into a flexible, resilient substance like shower curtains, fake leather upholstery from the 01970s, or nasogastric tubes. they evaporate from the plastic over time, so you inhale them and the plastic gets brittle. they also diffuse out of the plastic into whatever it's in contact with, especially oily things

in general any statement that refers to 'plastic' as a single material is wrong. the only thing the diverse materials called 'plastic' have in common is that you can mold them and that at least one of their major ingredients is a synthetic organic material, not even necessarily the majority

i think probably the concern over harm from human phthalate exposure will turn out to be baseless, but it's not implausible