The sugar industry is one of the oldest in the island of Mauritius and one of its most important foreign exchange earners. This industry employs a substantial labor force. The island produces on an average, 500,000 tonnes of raw sugar, in addition to special sugars. During the manufacture of sugar and its by-products a large amount of waste is generated, which can be environmental liabilities. This study reports the effects of 3 such wastes, namely vinasse (spent wash, slop), scum (press mud) and ash (residue left after burning of sugarcane bagasse), on 4 extractable heavy metals (Zn, Cu, Fe and Mn) in various soils of the island. It was found that addition of these wastes significantly increased the availability of Cu, Zn, Fe and Mn in the soils and consequently increased dry matter yield of maize grown in the amended soil. The increase in availability of heavy metals was found to be proportional to the application rate. 100 m3/ha was observed to be the upper threshold for vinasse addition without a negative effect on yield. Similar figures for scum and ash were 80 tons/ha and 40 tons/ha, respectively. Furthermore, the study showed that application rate at this level for a continuous period of 4 years did not increase the heavy meal content of the soil above the accepted norm. These sugar industry wastes have the potential to correct deficiencies of these 4 micronutrients in Mauritian soil without adverse effects. Hence use of these wastes in Mauritian agriculture can provide an economic and environmentally-friendly method of disposal, while at the same time helping to improve soil fertility and crop yield.