OECD 238 – Myriophyllum spicatum toxicity test

OECD 238 assess the toxicity of chemicals to Myriophyllum spicatum.

Myriophyllum spicatum is found in both static and flowing water. OECD 238 is based on the legacy ASTM test method (ASTM E1913); however, is modified as a sediment-free test system and estimates the intrinsic ecotoxicity of the test substance. The OECD 238 test method is recommended for test substances that degrade rapidly or are volatile.

OECD 238 performs a 14 day-exposure test to quantitatively determine the chemically related effects of generally 5 test substance concentrations on the vegetative growth of Myriophyllum spicatum.

OECD 238 and other tests with higher aquatic plants species can be an important component for the risk assessment of plant protection products and biocides. Because of the sediment-free testing system, the toxicity of different test compounds can be easily determined.

The low analytical complexity of the sediment-free test system can yield results that can be compared with results from the OECD 221* test method performed with the plant species, Lemna. OECD 238 does not replace other aquatic toxicity tests; but can be used in companion with other test results to obtain a more complete aquatic plant hazard and risk assessment for the test substance.

It is  important to have data on the test substance’s water solubility (OECD 105)* and the vapour pressure.  It can also be beneficial to have data on the different performance and physical and chemical properties of the material including structural formula, purity of the substance, stability in water and light, the Partition Coefficient (OECD 117)*, Dissociation Constants in water (OECD 112)*, and results of a test for ready biodegradability.

Many toxicology tests are used to meet regulatory requirements for different product applications; for any testing performed to meet regulatory or third party labeling requirements, it is strongly recommended to review requirements prior to testing with the appropriate agency to determine which tests should be performed for label claims or regulatory acceptance.

* OECD 105: Water Solubility

*OECD 112: Dissociation Constants in Water

*OECD 117: Partition Coefficient (n-octanol/water), HPLC Method

*OECD 221: Lemna species; Growth Inhibition Test

For more information on Toxicology Testing, contact our Environmental Testing laboratory at 847-483-9950 or info@situtest.com.