Registration Dossier

Administrative data

Endpoint:
additional toxicological information
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP, non-guideline study. Available as a publised report. Acceptable with restrictions.

Data source

Reference
Reference Type:
publication
Title:
Differential effects of phthalate esters on transciptional activities via human estrogen receptors α and ß, and androgen receptor
Author:
Takeuchi S, Iida M, Kobayashi S, Jin K, Matsuda T, Kojima H
Year:
2005
Bibliographic source:
Toxicology 210, 223-233

Materials and methods

Type of study / information:
Estrogenic and androgenic activity of diisobutyl phthalate.
Principles of method if other than guideline:
Highly sensitive gene reporter assays used to determine the endocrine disrupting potential of the test substance via a number of different routes.

Plasmids were prepared as per Kojima et al. 2003, 2004
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Purity: >99.0%
Source: Wako Pure Chemical Industriues, Ltd.

Results and discussion

Any other information on results incl. tables

Diisobutyl phthalate was observed to have the following effects (> 20% inhibitory effect with 10^-5 M DIBP)

Agonistic activity via ERα [REC20 = 6.1*10^-6 M]

Antagonsitic activity via ERß [RIC20 = 6.2*10^-6 M]

Antiandrogenic activities in hAR-transactivation assay

Negative results were observed for:

Agonistic activity via ERß

Antagonsitic activity via ERα

Androgenic activity in AR assay

Cytotoxicity or suppression of ß-Gal activity

Applicant's summary and conclusion

Conclusions:
Diisobutyl phthalate was found to exhibit ERα-estrogenic activity and antiandrogenic activity.
Executive summary:

In a non-GLP, non-guideline study Diisobutyl phthalate was found to was found to exhibit ERα-estrogenic activity and antiandrogenic activity.