Test No. 201: Freshwater Alga and Cyanobacteria, Growth Inhibition Test
The purpose of this test is to determine the effects of a substance on the growth
of freshwater microalgae and/or cyanobacteria. Exponentially growing test organisms
are exposed to the test substance in batch cultures over a period of normally 72 hours.
The system response is the reduction of growth in a series of algal cultures exposed
to, at least, five concentrations of a test substance. Three replicates at each test
concentration should be used. The response is evaluated as a function of the exposure
concentration in comparison with the average growth of control cultures. The cultures
are allowed unrestricted exponential growth under nutrient sufficient conditions (two
alternative growth media: the OECD and the AAP) and continuous fluorescent illumination.
Growth and growth inhibition are quantified from measurements of the algal biomass
as a function of time. The limit test corresponds to one dose level of 100 mg/L. This
study includes: the determination, at least daily, of the algal biomass; the measure
of the pH (at the beginning and at the end); microscopic observation. This Test Guideline
describes two response variables: average specific growth rate, and yield.
Published on July 28, 2011Also available in: French
In series:OECD Guidelines for the Testing of Chemicals, Section 2: Effects on Biotic Systemsview more titles