Publication Abstract

The effects of 4-nonylphenol and atrazine on Atlantic salmon (Salmo salar L) smolts

A. Moore, A.P. Scott, N. Lower, I. Katsiadaki and L. Greenwood

Exposure of Atlantic salmon (Salmo salar L.) smolts in freshwater to environmental levels of the oestrogenic chemical 4-nonylphenol (4-NP) (concentrations 5-20 m l l^-1) during the peak migration period had no significant effect on gill Na⁺K⁺ATPase activity, plasma vitellogenin (VTG) levels or hypoosmoregulatory performance as indicated by survival in sea water. However, where smolts were exposed to mixtures of 4-NP and the pesticide atrazine at concentrations of 5.0/1.0 m g l^-1 and 10.0/2.0 m g l^-1 respectively, there were significant differences in the gill Na⁺K⁺ATPase activity and plasma Cl^- and Na⁺ and increased mortalities when transferred to sea water. Smolts retained for a short period in an estuary with high levels of oestrogenic contamination showed no significant differences in gill Na⁺K⁺ATPase activity, plasma vitellogenin (VTG) levels or hypoosmoregulatory performance compared to fish maintained in an adjacent uncontaminated estuary. The results of the study are discussed in relation to the effects of environmental levels of oestrogenic contaminants on smoltification and migration in wild salmon.

Reference:

A. Moore, A.P. Scott, N. Lower, I. Katsiadaki and L. Greenwood, 2003. The effects of 4-nonylphenol and atrazine on Atlantic salmon (Salmo salar L) smolts. Aquaculture, 222: 253-263.