Ecotoxicity - Unicellular green algae, diatoms and cyanobacteria: Inhibition of algae growth (algicide test) (ISO 8692: 2012; ISO 10253: 2016 standards; OECD 201: 2011 guideline; EPA-OPPTS 850.5400; EU 440/2008).
In this test, unicellular green algae, diatoms or cyanobacteria cultures selected in exponential phase of growth are exposed to various concentrations of the tested substance under the conditions defined by the test. The product solutions for assay with algae are incubated for a period of 72 hours. During this period, the cell density in each of the product solutions is measured at least every 24 hours and growth inhibition is determined in relation to a control culture. This test is carried out with microscopic algae and/ or cyanobacteria, using in our laboratory the strains recommended by the standards mentioned.
- ISO 8692: 2012 standard states that at least one of the following planktonic algae should be tested: Pseudokirchneriella subcapitata (= Selenastrum capricornutum) and Desmodesmus subspicatus (= Scenedesmus subspicatus).
- COUNCIL REGULATION (EC) No 440/2008 states as preferred algae species Selenastrum capricornutum and Scenedesmus subspicatus.
- OECD 201: 2011 consider suitable the following strains: the green algae Selenastrum capricornutum and Scenedesmus subspicatus; the diatoms Navicula pelliculosa; and the cyanobacteria Anabaena flos-aquae and Synechococcus leopoliensis.
- EPA-OPPTS 850.5400 (1996) guideline was developed for Selenastrum capricornutum and Scenedesmus subspicatus, but it states Anabaena flos-aquae and Synechococcus leopoliensis, may be used with some specific modifications in the test protocols.
- ISO 10253:2016 Standard, for determination of the inhibition of growth of the unicellular marine algae Skeletonema sp. and Phaeodactylum tricornutum by substances and mixtures contained in sea water or by environmental water samples (effluents, elutriates, etc.).
As a positive control substance, we use a solution of potassium dichromate, unless any regulation or the customer indicates the use of another substance. Other species of algae can be tested upon request.