Brass screws holding light covers

[marthas_ear]

Hi,
Should I be concerned with plastic screws being replaced with brass ones on our underwater lights? Think they are pentair lights.
Ron wanted to replace the plastic screws, thinking brass were "marine" quality. But I am wondering about leaching in a closed system like our pool...
is this a case where plastic would be better for screws?

 

[greenacres]

Maybe stainless steel would be best?