I guess I'm not following you. Any hard or NON porous surface will reflect high and mid frequencies. Sub sonic frequencies will go right through those same surfaces, but without a huge amount of thickness it wont affect the bass frequencies much either (meaning the standard 1" panels) . The only real block for the lower frequencies is MASS. Regular insulation doesn't really absorb all the low frequencies, just dampens and slows it down before it hits the wall behind the insulation and then reflects back into the room to be "slowed down" and attenuated again by the same insulation.
Instead of wrapping with plastic or paper, I utilized faced insulation (saved a step) for my bass traps in the front corners. If I deem it to be too much reflection on the high end, I will stand up some of the left over IS300 rigid 1" insulation I have left after the build in front of them.
There are many ways to go about taming bass, but all seem to be very similar for the DIY crowd. Do a search for bass traps and spend some time reading the threads around here.
For non-bass traps, any wrapping of the fiberglass with plastic is going to negate the absorbtion of the high/mid frequencies you want. As far as health concerns, after you wrap the insulation with fabric stop brushing against it, it will NOT introduce fibers into the air. It's just a pain during the initial handling. Gloves, long sleeved shirt and a mask might be in order for you. Also, a large shop vac with the hose removed makes for a decent air filter during this process!