Tradescantia Micronuclei (Trad-MCN) Test For Environmental Clastogens

Abstract

The Tradescantia Micronuclei (Trad-MCN) test is a well-validated system for the in situ monitoring of gaseous mutagens or radiation and bioassay for toxicity or clastogenicity of liquid types of environmental pollutants, drugs, and food additives. For testing gaseous mutagens or radiation, excised Tradescantia in-florescences containing meiotic pollen mother cells may be exposed to the agent at the chosen pollution sites or in the treatment chambers. For testing liquid types, the cuttings are allowed to absorb the agent through the stem and transport the agent to the meiotic pollen mother cells. The chromosome fragments that are induced by the agent at the early meiotic stage become micronuclei at the tetrad stage. The acetocarmine squash method is utilized to prepare microslides, and frequencies of micronuclei among a large population of tetrads are the reliable indicators of the chromosome damage. This test reveals directly the magnitude of chromosome damage in the germ cells of an eukaryote. It is relatively simple, versatile, and efficient. Results of the test can be obtained and analyzed in 24–48 hr. It is, perhaps, the most inexpensive test known at the present time.