The present work deals with the information about pesticides as environmental pollutants and consequent health hazards with special reference to mutagenicity, carcinogenicity and teratogenicity. Historical review of pesticide mutagenesis reveals the researches done by different workers with various mutagenicity bioassays in order of increasing organisational complexity. Besides the advantages and limitations of different test methods, micronucleus test has been discussed in detail. The statement about the present problem and its suitability has also been mentioned. The author has presented gist of the results obtained for each pesticide. The terminal portion of the work deals with the “REFERENCES” containing an alphabetical list of literatures cited in the text of the present thesis. In appendix the list of publications and reprints of the author have been attached.