A dilute DDT dispersion in water heated above 90[degree] C, boiled or autoclaved, was shown to decompose chemically. The breakdown products were not detd., but it is possible that those resulting from heating or boiling are distinct from autoclaved breakdown compounds. None of the compounds were found to have a maximum in the 520-560 m[mu] range (reddish colors). This includes dehydrochlorinated p p''-DDT and DDA. Aerated and aged dispersions showed no chemical breakdown of DDT, but a physical change took place in that DDT was more concentrated at the bottom and sides of the flask.