Effect of teratogenic and related dyes on the haemoglobin nitrite sensitivity reaction.

The teratogenic dyes trypan blue and Evans blue have a marked and immediate action on the oxidation stability of intracellular haemoglobin in rats. Of the proved non-teratogenic substances tested only o-tolidine has an effect on the haemoglobin stability, and this effect is slow. It is suggested that the effect of the teratogens on the haemoglobin oxidation sensitivity is due to interference with the protein component of the flavoprotein enzymes.