Why is the cadmium SGV for allotments lower than the provisional limit for applying sewage sludge to land?
The cadmium Soil Guideline Value (SGV) for the allotment land-use scenario is lower than the provisional cadmium limit for applying sewage sludge to agricultural soils of 3 mg kg-1 DW set out in The Sludge (Use in Agriculture) Regulations 1989 (TSO, 1989; DoE, 1995). The Sludge Regulations apply to the protection of soil fertility from the use of sewage sludge in agriculture and are used in conjunction with a code of practice for the use of sludge and other management guidelines (DoE, 1995; ADAS, 2001). Although the sludge application limit for cadmium is intended to restrict entry of cadmium into the human and animal food chains via crops, it is very difficult to compare health protection objectives directly with the SGV. However, it is useful to note that: • SGVs relate to multiple sources and forms of cadmium contamination and not only those from a single source such as sewage sludge; • allotment holders are not subject to management guidelines or a code of practice, and therefore o