Lead

Interpretation of Lead Levels in Blood
Blood lead concentrations <0.15 µmol/l indicate background exposure and do not indicate a risk to the food chain or to animal health. Values above this indicate exposure. Lead levels greater than 1.2µmol/l in the blood are consistent with a diagnosis of lead poisoning in cattle, small ruminants, birds and miscellaneous species.
For animals from Scotland, concentrations >0.48 µmol/l in blood should be reported to Food Standards Scotland (FSS). Similar concentrations in animals from England should be reported to an APHA veterinary investigation officer to take forward as a potential food safety investigation.

Lead analysis indicates raised lead concentrations in blood which may be detrimental to animal health and is a cause for concern in terms of food safety due to persistent lead residues. Under the Food Safety Act 1990, and related legislation, farmers and their advisers are required to show due diligence to protect the food chain.
During an investigation it is advised that the exposed group of animals is placed under voluntary restriction (not moved off the holding) until further information is gathered and the risk analysed. Access to the source should be restricted as soon as it is identified.