Other reference standards
were neat or >95% purity compounds obtained from SigmaeAldrich,
Dr. Ehrenstorfer and Tokyo Chemical Industry. Isotopically labeled anthracene (D10), benzophenone (D10), bis(2-
ethylhexyl) phthalate (D4), bisphenol A (D14) from SigmaeAldrich
and PFOA (13C2) from Wellington Laboratories served as internal
standards