The Norwegian Food Safety Authority has asked the Norwegian Scientific Committee for Food Safety (VKM) for a statement regarding the hygienic aspects of the use of sludge from the hatchery and sludge from marine aquaculture as a fertilizer and soil improvement. This statement was prepared for the sludge containing no dead fish.
VKM concludes that the probability that infectious agents pathogenic for fish are present in the sludge from a hatchery and fish farms will depend on the medical history of the relevant facilities.
The risk of spreading infectious agents from freshwater system to other freshwater systems by untreated sludge is considered to be greater than similar risk of spreading between the marine sites or from the marine sites to freshwater systems using the sludge from the marine sites.
The statement concludes that it is very unlikely that infectious agents (viruses, bacteria and parasites) that occur in sludge from a hatchery or sludge from marine fish farms, represent a danger to humans when used as fertilizer or soil improvement.