Congenital Malformations Produced by Injecting Azo Blue into Pregnant Rats.

Abstract

The injn. of 1 cc. of a 1% aqueous soln. of the diazo dye azo blue into female rats on the 7th, 8 th, and 9th days of gestation resulted in congenital malformations in 59% of living fetuses removed on the 20th day of gestation. Trypan blue injd. under the same conditions caused malformations in 49% of the offspring. After both dyes the patterns of abnormality were similar, con sisting mainly of defects of the brain, eye, and vertebral column, but occasionally involving also cardiovascular and genitourinary organs and the appendages.