EnviroSystems, Inc., a Woman Owned Small Business (WOSB), provides a full range of environmental toxicological and analytical chemistry testing services specifically designed to address issues related to detecting and quantifying toxicity of leachates, surface waters and sediments. Amphibian evaluations are conducted using Frog Embryo Teratogenesis Assay – Xenopus, or FETAX assays.

FETAX assays demonstrate potential adverse ecological impacts by monitoring development and growth of eggs and tadpoles. Newly fertilized frog eggs are exposed to a range of sample types including, leachates, surface waters and sediments. Embryonic development is monitored along with tadpole growth and development to assess teratogenic developmental effects and chronic, sublethal effects on growth.

  • Standard FETAX assays, using relatively short exposure times, 96 hours, provide both mortality and sublethal effects data more quickly than other water column or sediment assays.
  • Basic protocol, providing for the evaluation of waters and leachates, can be easily modified to allow assessment of sediments and soils.
  • Extension of exposure periods from the standard 96-hours to 240- hours (10-days) allows for assessment of long-term, chronic exposure effects.
  • Alternative species including indigenous frogs and toads may be used in place of Xenopus. Use of species other than Xenopus may however, limit test availability.

Incorporation of FETAX assays into overall testing schemes designed to evaluate potential toxicity of leachates, ground water, surface waters and sediments is an additional tool to assess potential impacts. The assay generates both acute and chronic exposure endpoints for establishing site prioritization, characterization or for documentation of cleanup success and monitoring.

Adult frogs with fertilized eggs, male frog is the smaller of the pair.Embryos at Start of AssayTadpoles After 24 Hours ExposureTadpoles at End of Assay - 96 Hours