Is there any type of plastic that’s not good to be in tanks?

[PattysAquatics]

So I have a diy spray bar and my suction cups to hold it up both decided to not work anymore so I temporarily have it up with a zip tie. I’m looking at my hardware store for some kind of hook to use that would hang over the back of the tank. My question is is there any type of plastic I should steer clear of? I don’t want to get something and have it kill all my fish. I found this hook for over a door but for the material it just says plastic. Anyone know or use something for there spray bars that would work? 

[CT_]

I think the answer is maybe. 

Most base plastics aren't harmful because they just don't dissolve or migrate into water (this includes PLA, contrary to popular belief).  But plasticizers (things that make plastic tougher/softer, think BPA that everyone freaked out about) can and technically do leach.  "food grade" and approved for food contact and potable water plastics (like pvc pipe, but not drain ABS as far as I know) are supposed to not leach anything harmful. 

 

You also have to worry about pigments leaching.  Black is almost always carbon black (safe) and white is almost always TiO2 (also safe).  Things like yellows and reds used to have cadmium but I don't think they do anymore.

 

All that said, in my opinion, If It's not a food or water grade product It's probably still okay, though it would be hard to tell. 

 

If you're breeding fish I'd stay away from polycarbonates(PC) and epoxies (including aluminum cans, though why would that be in your fish tank?!) as they can contain bisphenols (BP*) and at least BPA and I think BPS are known to cause reproductive harm in some animals.