Hey A_A
There's a lack of human evidence due to it being tricky to find people willing to take part in something so dangerous.
There's other toxic chemicals found in sex toys which also produce a stick, smelly, substance. And many that produce no smells or stickiness - plastic dyes, plating, and more.
Some of these things can be a lot worse than phthalates.
I'm working with a lot of companies outside of the sex industry as well as inside, to work out what is 100% body safe.... it has even boiled down to silicone not even being safe when it hasn't been left to be cured fr the correct time etc.
Really it's scarey.
I was chatting with a few researchers too about low progestin levels in female rats led to infertility due to contact with phthalates. These studies really interested me, as I, have tested at least 100 phthalate filled sex toys and recently found out that I have an adnormally low progestin levels which can't be explained via blood testing and things. The professionals I chatted with said phthalates could be the cause, but there's sadly no way of telling now as I have no solid evidence about my progestin levels before using these toys, how often I used these toys, and the level of phthalates in each toys.
I'd also like to note that toys with phthalates aren't regulated, a company can whack as many of them into a product as they like and sell it as an adult products. Where as phthalates are regulated in childrens toys where you are only allowed to sell, make, import toys containing 0.1% at most as these products could become in contact with childrens mouths.
When you think about it, anything toxic doing in contact with vagina also has easier access into the blood stream and will miss the filtration process too - a lot of toxic chemicals are filtered out via the liver before going into the blood stream.
Anyway there is a lot of evidence about how bad phthalates are and recently there have been a few human based studies involving diabetics as phthalates could be a factor in causing the onset of type 2, but it's again tricky, as diabetics are more likely to be incontact with phthalates due to certain medical equipment.
But yes they really shouldn't be used, and regulations do need to happen, but sadly these will take a long time.