There is evidence of declining trends in T levels among men in recent decades, as well as trends in related conditions at multiple life stages and in both sexes. There is also animal and limited human evidence that exposure to phthalates, chemicals found in plastics and personal care products, is associated with reduced androgen levels and associated disorders.

Use of environmentally persistent polybrominated diphenyl ether (PBDE) flame retardants has been reduced because of concerns about health effects, but potential health effects of organophosphate (OP) flame retardants used as alternatives to PBDEs have not been extensively investigated, despite evidence of widespread human exposure. Meeker and Stapleton (p.