THE TOXIC EFFECT OF PENTACHLOROPHENATE, A HERBICIDE, ON FISHERY ORGANISMS IN COASTAL WATERS-I

It has been reported that the 24-hr. TLm's of sodium pentachlorophenate (PCP) for fresh water fishes ranged from 0.07 to 0.6 ppm1, 2, 3). No report has been made so far of its toxic effect on marine organisms. The study was undertaken to answer a question whether or not PCP is toxic to organisms in coastal waters. Under a condition of keeping one test organism in 1 to 2 liters of the solution under test at 29°C and of daily renewal of the test solution, the 24-hr and 48-hr TLm's of PCP were found to be 0.09 and 0.08 for “guchi”, Nibea albiflora, 0.40 and 0.25ppm for “warasubo”, Odontamblyopus rubicundus, and 3.4 and 2.3ppm for “shiraebi”, Leander japonicus, respectively, and the 24-hr TLm to be 0.20ppm for eel, Anguilla japonica. The avoidance reactions of “guchi” to PCP in a gradient tank4) showed that the fish could discriminate PCP at level of 0.2 to 0.3ppm.