Survey and assessment of mammalian estrogen biological assays for hazard characterization.

With the growing awareness and concern regarding estrogens in the environment, the selection of reliable and appropriate methods for their detection and characterization has taken on considerable importance. The relevant literature covering the period from 1920 to 1996 was surveyed to identify methods that have been used to assay estrogens in mammalian systems. The estrogen biological assays identified were grouped into four categories: (1) reproductive tract response; (2) non-reproductive-tract target tissue response; (3) estrogen receptor binding; and (4) estrogen receptor-dependent transcriptional expression. The biological assays were summarized and their advantages and disadvantages discussed. A possible testing scheme also was provided to characterize estrogens, anti-estrogens, and pro-estrogens (chemicals metabolically converted to estrogens)..