SYMPOSIA PAPER Published: 01 January 1990

Evaluation of Protocols for the Assessment of Phytotoxicity


Industrial chemicals and waste substances were tested in laboratory and growth chamber tests for toxicity to terrestrial and aquatic plants. Protocols for these tests were outlined in the 18 December 1978 and 16 March 1979 issues of the Federal Register. Tests on terrestrial plants included effects on seed germination and seedling growth as criteria of injury. Potential toxicity or stimulation of algae was assessed using Anabaena flos-aquae, Chlorella vulgaris, Skeletonema costatum, and Selenastrum capricornutum. Duckweed, Lemna minor, was used to assess potential phytotoxicity to higher aquatic plants. Evaluation of the results of tests showed that problems were encountered in implementing the test protocols. Unexplained variation in the data obstructed the calculation of confidence limits of the EC50 for the test substance with some species in the seedling growth test. The criteria for calculating the EC50 in Lemna and some algal tests were not met. Alternative use of analysis of variance (ANOVA) was hampered by heterogeneity of the variance in the test on Anabaena. In the algal tests chlorophyll appeared to respond differently than dry weight to the test substance. Although the protocols for these tests appear adequate, improvement is possible.

Author Information

Sirois, DL
Boyce Thompson Institute, Ithaca, NY
Price: $25.00
Contact Sales
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Developed by Committee: E47
Pages: 225–234
DOI: 10.1520/STP19066S
ISBN-EB: 978-0-8031-5148-2
ISBN-13: 978-0-8031-1397-8