Box 7J EC Directive on sewage sludge

In the EC, Council Directive (86/278/EEC) regulates the use of sewage sludge in agriculture and sets limit values for concentrations of heavy metals in sludge and soil. The maximum values permitted by the EU are in nearly all cases higher or at least equal to the maximum values permitted in the different European countries. Recent research findings on the effects of heavy metals on soil microbiology (Chaudri et al, 1993) show that significant reductions in Rhizobium numbers occur at metal concentrations well below the current EU upper limit for all metals. Recommendations for an update of the Directive have also been made by an independant scientific review on the use of sewage sludge in agriculture (UK Ministry of Agriculture, Fisheries and Food, 1993).