| dc.description.abstract | Certain species of life are incompatible with mechanisms associated with industries using natural
waters for cooling or manufacturing. Many industries have increasing concerns with the
interference of water flows due to aquatic organism accumulations ultimately causing flows to
decrease and interfering with the mechanical processes. One species of particular concern in the
United States and Europe is the zebra mussel (Dreissena polymorpha). Many control methods for this
species have been attempted with limited success. J\.new chemical product developed in France,
Mexel 432, shows promise as a control agent. The Lake Superior Research Institute (LSRI) has
conducted tests with this mixture with sensitive non-target species to determine the acute
toxicity of Mexel.
The three animal species tested were a cladoceran, Daphnia magna, fathead minnow, Pimephales
promelas, and the rainbow trout, Oncorhynchus mykiss. Daphnia magna was chosen because it represents sensitive invertebrate species that ,may inhabit lakes and large rivers where Mexel could
potentially be discharged if used as control' agent for the zebra mussel.
Organic matter was varied between acute tests with the cfadoceran because it has been shown in
studies conducted in Europe that water quality has strong influence on the toxicity of Mexel to
aquatic organisms. The cladoceran was tested in both short-term acute tests and a long-term
chronic test. .The fathead minnow was chosen because it represents the warmwater group of fish.
Rainbow trout represent .the coldwater fish species. Both fish species were tested as juveniles
(very sensitive life stage) in seven-day exposures. | en_US |
