Registration Dossier

Administrative data

Endpoint:
additional toxicological information
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Scientific publication, relevance of the applied assays for hazard / risk characterisation unclear

Data source

Reference
Reference Type:
publication
Title:
Estrogenic Activity of Impurities in Industrial Grade Bisphenol A
Author:
Terasaki M et al.
Year:
2005
Bibliographic source:
Env Sci Tech

Materials and methods

Results and discussion

Applicant's summary and conclusion

Conclusions:
Some of the substances described in the publication are impurities of the reaction mass. The data may be of scientifc interest, but it is impossible to extrapolate these in vitro results from artificial test systems to the in vivo situation. Therefore, the publication has been included for the sake of completeness but is not relevant for hazard characterisation.
Executive summary:

The estrogenicities of 10 compounds found as impurities in industrial grade bisphenol A (BPA) were measured by yeast two-hybrid assays incorporating the human estrogen receptorR(hERR) or the medaka fish (Oryzias latipes) estrogen receptor R (medERR). Five impurities showed greater activity than BPA itself in an agonist assay for hERR. p-Cumylphenol, the most active of the impurities in the hERR assay, was 12 times as active as BPA. The REC10 (10% relative effective concentration: 10% of the activity of 10-8M 17â-estradiol) was 710 nM. Five impurities showed greater activity than BPA in an agonist assay for medERR: 4,4¢-(1,3-dimethylbutylidene) bisphenol and 2-(4¢-hydroxyphenyl)- 2,4,4-trimethylchroman were nearly equipotent and 9 times as active as BPA, and the REC10 values of these compounds in the medERR assay were 280 and 320 nM, respectively. Comparison of the experimentally determined estrogenicities of mixtures of BPA and 4,4¢-(1,3-dimethylbutylidene) bisphenol and those calculated by the concentrations addition (CA) method confirmed the suitability of the method for the prediction of the estrogenicities of the mixtures of BPA and its phenolic analogues. The measured estrogenicities of four samples of industrial grade BPA and laboratory grade (pure) BPA were not significantly different in either the hERR assay or the medERR assay (p > 0.05 in each case). We conclude that the impurities in industrial grade BPA, although some are of much higher estrogenic activity than BPA itself, do not significantly increase the estrogenicity of the industrial compound and therefore do not increase possible adverse health effects from such activity.