A SPECTROSCOPIC STUDY ON EFFECTS OF BENZENE UPON HUMAN DNA IN THE PRESENCE OF

Abstract

The free radical generated substances like Benzene (Bz ) showed to be caused a significant (P<0.01) elevation in absorbance of human DNA mixture ( DNA , TE buffer and Bz) after previous exposure to UV-B light with different time periods in comparesom with control groups. The changes investigated with two types of UV spectrophotometer (manual and screening types) while the exposure done with manually designated UV-B light source. The changes in absorbance observed with usual UV spectrophotometer and with λ max scanners UV spectrophotometer could be attributed to formation of more doubled bonds with basic nitrogenous bases of used DNA as a sequels to the presence of free radicals which generated by Benzene and U.V.- B in aqueous solution .The elevation of absorbance reduced by cooling the mixture with 4оC after the last period of UV – B light exposure. These results reflected the dramatic changes in human DNA directly in case of presence of Benzene and UV – B light which may be explained the wide correlated diseases as well as presented a possible prophylactic method by using cooling which reduce these effects and for that may delayed the development of such diseases . Lately the research presented an easy method to investigate the possible changes in the human DNA under the circumstances of the experiment rather than these of difficult , expensive and more dangerous methods .