Assessment of heavy metals in sewage sludge and their accumulation in cabbage (Brassica oleracea var capitata)

Heavy metals accumulation in sewage sludge is a major concern to the environment especially when it is considered to be used for crop production. This research aimed at checking the levels of heavy metals in faecal matter based fertiliser products and if there is any subsequent absorption by cabbage when used in the field. Sewage sludge was used as major raw material to produce sludge, biochar, normal compost and vermi compost. Tests were done on the products and later on cabbage tissues. The results obtained showed that the products had no alarming levels of heavy metals as well as the levels in the tissues were not beyond the permissible levels. This indicates these products as safe for cabbage production.