Thermoplastic compositions that reflect ultraviolet light are provided herein, along with articles of manufacture and methods of fluid purification using the same. The thermoplastic compositions preferably comprise a suitable thermoplastic material and microparticles of UV reflective material, such as aluminum or stainless steel. The thermoplastic compositions are useful, for example, in forming articles of manufacture comprising a UV reflective surface that are suitable for use in a water treatment system in connection with a UV light source.