Acute toxicity of the antisapstain chemicals DDAC and IPBC, alone and in combination to rainbow trout (Oncorhynchus mykiss)

The antisapstain chemicals DDAC and IPBC were tested for acute toxicity with juvenile rainbow trout. The 96-h LC50 estimates were 537 mu g DDAC/L and 67 mu g IPBC/L. The two chemicals were also tested as a mixture (10:1) and as the commercial formulation NP-1. The 96-h LC50 for NP-1 was 581 mu g DDAC + IPBC/L and was 494 mu g DDAC + IPBC/L for the 10:1 mixture, The two chemicals exhibited mildly antagonistic behaviour when present in the mixture or formulation. Thus, the data indicate that DDAC and IPBC do not pose any risks of synergistic effects to juvenile rainbow trout when present concurrently in solution. (C) 1999 Elsevier Science Ltd. Ail rights reserved.