Biomonitoring of paper mill effluent using fish ventilatory signals

Murray-Darling Freshwater Research Centre

MDFRC item.

Many industries discharge waste waters into our river systems. It is important that these discharges be monitored on a regular basis to ensure that there is no disruption to the overall health of the system. In conjunction with Australian Newsprint Mills Ltd (ANM) at Albury, NSW, the Murray-Darling Freshwater Research Centre (MDFRC) has designed, built and installed a prototype fish ventilatory biomonitoring system into ANM's wastewater discharge, similar to commercial systems produced in the United States and Europe. Eight eastern rainbow fish (Melanotaenia duboulayi) are housed in separate one litre flow-through chambers. Each fish is constantly monitored by computer for changes in frequency and strength of opercular movement. Due to the sensitivity of the system, changes in effluent quality are detectable at a sublethal level of 5% concentration of raw effluent, allowing ANM to rectify the problem before chronic levels are reached, minimising the effect on river biota.