Teratological effects of 2,4-dinitrophenol, produced water' and naphthalene on embryos of the inland silverside Menidia beryllina

Abstract

Embryos of the inland silverside Menidia beryllina were exposed to 3 teratogens: 2,4-dinitrophenol, (2,4-DNP), "produced water" (PW), and naphthalene (NPH). Tests were conducted by placing single embryos in glass tissue culture tubes containing 6 ml of saline exposure media. Twenty tubes were used for each exposure concentration and for controls. A severity-index based upon craniofacial, cardiovascular, and skeletal terata was used to rank responses each day. The compounds tested caused teratogenic expressions in embryos and larvae exposed from the 2- to 4-cell and blastula stage through 7 to 8 d post-fertilization. However, combined survival in control embryos and larvae, and those exposed to respective teratogens, were not significantly different in 5 of 6 tests, except the 2- to 4-cell embryos exposed to 2,4-DNP. There was a marked increase in the relative frequency of terata with increasing nominal exposure concentrations of each compound