In the previous year of this contract (1) studies were initiated in the following areas: 1) Sludge heavy metal characterization of North Toronto, Newmarket and Point Edward sewage treatment plants. 2) Heavy metal contamination of farm soils and vegetation resulting from sludge applications (Newmarket area). 3) Surface water, heavy metal contamination resulting from sludge disposal, 4) Assessment of analytical data. During the present year, work was continued in all these subject areas, heavy metal contamination studies of soils, vegetation, groundwater and surface water were carried out at the Burlington Skyway plant disposal farm and the North Toronto plant disposal area. A study of garden vegetable contamination due to the use of sludge for home gardening was also initiated. Again as in the previous year emphasis was placed on using standard reference materials to give validity to the analytical data.