Osmoregulation in freshwater invertebrates in response to exposure to salt pollution

Sponsor: Water Research Commission
Leader: Dr WJ Muller
Staff: Mr AK Gordon, Ms N Ketse, Mr TJ Human, Ms AJ Holland
Students: Mr G Tutt (Honours: Ichthyology and Fisheries Science), Mr G Williams (3rd year: Entomology)
Duration: April 2005 - March 2008

Aims and Objectives

Riverine macroinvertebrates are excellent indicators of water-borne pollutants as they are in constant contact with them in the water column and several species have been shown to be suitable laboratory-test organisms. Methods are being developed for generating chronic toxicity test data for indigenous species, valuable for deriving water quality guidelines, at both organism and sub-organism levels. However, interpretation of these toxicity test results remains elusive as little is known of the biology and physiology of the selected test species. Fundamental research is therefore necessary to establish the osmoregulatory properties of organisms currently being evaluated as chronic toxicity test species.

The aims of this project are therefore to:

  •     undertake a literature review and identify toxicants (salts) for use in exposure experiments, in consultation with industry and research partners;
  •     undertake acute and chronic toxicity tests using the salts and selected indigenous macroinvertebrates;
  •     undertake physiological experimental research (oxygen consumption and osmolarity) using samples generated during acute and chronic toxicity tests;
  •     use the experimental results to evaluate the boundary values for the selected salts for application in environmental water quality management and setting resource quality objectives.

Last Modified: Fri, 14 Aug 2015 10:54:13 SAST