The Risk To Health of Chemicals in Sewage Sludge Applied To Land

Abstract

A Working Group organized by the World Health Organization, Regional Office for Europe, considered the risk the health of chemicals in sewage sludge applied to land. Cadmium appears to be the most important contaminant because it can be accumulated from the soil by certain food plants. Other metals in sludge are unlikely to cause health problems if sludge applications do not exceed the nitrogen requirements of the crops. Organic pollutants such as pesticides, polychlorinated biphenyls and polycyclic aromatic hydrocarbons are not significantly absorbed by plants through their roots but may be ingested with soil by some grazing animals. The total human intake of identified organic pollutants from sludge application to land is minor and is unlikely to cause adverse health effects. The influence of soil properties on plant uptake of cadmium is reviewed since current limits for cadmium in soils and sludge vary greatly between different countries.

Metal Contents in the Tissues of Lutjanus fulviflamma (Smith 1949) and Epinephelus tauvina (Forskål 1775) Collected from the Arabian Gulf

“…The WHO recommendation (1972) cited by Dean and Suess (1985), allows a daily intake of 60-70 µg cadmium, to reach this limit also one has to take a good quantity (more than one kilogram) of fish flesh. Further, the mean values of Table 2.…”

Evaluation of the Pozzolanic Activity of Sewage Sludge Ash

“…Application of sewage sludge without appropriate management might have adverse impacts on human health and the environment [11]. Legislative barriers for sewage sludge disposal options make incineration is the most attractive disposal method [12].…”

X‐ray fluorescence analysis of sludge ash from sewage disposal plant

“…5,6 Heavy metals absorbed in crops can affect human health through accumulation in food and fodder plants when sewage sludge ash is used as fertilizer. 7 In particular, inorganic constituents such as phosphates and heavy metals are concentrated to about ten times normal levels in the ash by incineration of sludge: sewage sludge ash contains heavy metals in high concentrations compared to incineration residues of municipal solid waste. 1,8,9 The heavy metals are concentrated in stable phosphate crystals in sewage sludge ash.…”