The lead and cadmium content of samples from the most commonly utilized feed additives (limestone, dicalcium phosphate, sodium chloride,
zinc, vitamin and trace element premixes) was analyzed by means of atomic absorption spectrophotometry. It was found out that up to 30% of the allowed
limit for lead content and up to 100% of the allowed limit of cadmium content in compound feed for layer hens could be attributed to limestone, therefore
emphasizing the importance of monitoring lead content of this ingredient. Additives such as dicalcium phosphate, trace element mixes, vitamin premixes
and particularly sodium chloride, could also contribute to the higher lead and cadmium content in compound feed. As these ingredients are included at
quite low levels, the risks for increasing lead and cadmium content of compound poultry feed through them is assessed as insignificant.
D. Alexieva1, S. Chobanova2