I will begin with the fact that the sex toy industry is not currently regulated. This means that there are no rules set in stone that require manufacturers to disclose the “ingredients” used to make their toys. So technically we [the public] don’t really know what most toys are made of!
It’s fair to say that a majority of sex toys are typically made with poor grade materials because they’re cheap and easy to produce. That list of unsafe materials is long, and you’d get bored and/or frustrated [as I do] reading through all of them. So let’s keep it simple and concentrate on the safest sex toys materials: silicone, glass, metal, ABS hard plastic, ceramic, and some wood or stone [if sealed properly].
There’s a couple things; the material’s porosity and the material’s toxicity. Materials such as jelly rubber, PVC, TPR, realistic skin-like stuff, and many more, are all porous, cannot be completely sterilized, and they break down over time. These materials have tiny little pores that trap bacteria and STDs. To clean these types of toys you can use warm soapy water, but you cannot boil them to completely sterilize them. This puts you at risk of infections if you them anally AND vaginally, or if you're sharing them with a partner.
Some of those less safe materials are also toxic if they contain plasticizers like phthalates or other unsafe chemicals, which actually harm your body by causing rashes or even in more sever cases reproductive issues. Additives like these are used to give the toy a softer, more ‘realistic’ feel and typically have a strong plastic or chemical smell to them. You could use condoms with these toys, but honestly I suggest to just throw them out!
So, that’s the short version, but if you’re looking for a little more info check out these articles:
All the toys available at IGNITE Pleasure Products are made of body safe materials.