VEVOR 5/8 Inch x 500Ft PEX Tubing Oxygen Barrier O2 EVOH Pex-B Red Radiant Floor Heat Durable Plumbing Flexible for Residential Commercial Radiant Floor Heating Pex Pipe

I did not find any information about UV resistance in the product description or customer reviews.

Yes, the product description states it is compatible with pex crimp fittings. The tubing comes with clamps and a pipe cutter for installation using the clamp connection system which involves crimp fittings.

Yes, the product description states that it is suitable for potable water transmission.

The product description mentions that this PEX tubing is suitable for radiant floor heat systems, solar water heater systems, and central air-conditioning piping systems. While customer reviews don't explicitly mention outdoor installations, one review talks about burying the tubing which suggests it can be used outdoors.

I did not find any information about toxic materials in the product description. However, the product is certified by regulatory bodies and complies with safety standards. For detailed information, it's best to consult the manufacturer.