Terotogenic effects in the chick embryo caused by esters of phthalic acid.

Abstract

Eight commercially available phthalic acid esters were investigated to determine their effects on the developing chick embryo. Dibutoxyethyl phthalate was capable of causing teratogenesis in these embryos. Congenital malformations such as crania bifida and anophthalmia were observed in newly hatched chicks receiving this phthalate ester into the yolk sac before the third day of embryonic life. Also, marked exophthalmia, resulting from an absence of bone tissue forming the orbit of the eye, and blindness, due to failure of the cornea to develop, were other malformations observable in chicks treated with this phthalate ester. The data suggested that dibutoxyethyl phthalate, di-2-methoxyethyl phthalate and octyl isodecyl phthalate are capable of causing damage to the central nervous system of the developing chick embryo. This was manifested after hatching by grossly abnormal behavior of chicks, such as tremor, nonpurposeful bodily movement and a total incapability of either standing or walking normally. These esters varied in their toxigenic properties for the chick embryo. Statistical analyses were conducted on the data. It was determined that differences in the numbers of deaths occurring in phthalate-treated groups compared with control groups of chick embryos were significant at less than the .01 level.