Radionuclides in commercial children's food consumed in Croatia

This work presents first results of radioactivity measurements in selected early children's food (<year) which are commercially available, widespread, and typically consumed in Croatia. The samples are categorized according to growth of a child, from its first nourishment, adapted powdered milk, to its first solid food, cereal porridge powder, homogenized fruit porridge and finally mushed meals with vegetables and/or meat. Natural ⁴⁰K is detected and quantified in all of the samples (from 30 Bq/kg up to over 250 Bq/kg), with highest values in powdered milk (150–200 Bq/kg) and cereal porridge (maximum value 262 Bq/kg in the sample containing oats). ²²⁶Ra was visible in all types of foods in the majority of the samples in small amounts, not exceeding 0.92 Bq/kg. ¹³⁷Cs was detected only in some of the powdered milk samples with maximum measured activities (0.65 ± 0.32 Bq/kg and 0.38 ± 0.14 Bq/kg) found in the samples where ⁴⁰K showed largest values, too. ⁹⁰Sr was detected in majority of samples of fruit, vegetable and meat meals, reaching up to 0.065 ± 0.025 Bq/kg in vegetable porridge containing potatoes and carrot. It was detected only in one sample of powdered milk, and in none of the cereal porridge samples. All of the presented results are within the values reported by other studies around the world. The results are used to estimate the ingestion doses to evaluate the radiological health risk, which is calculated to be 0.72 mSv/year. The contribution of ⁴⁰K prevails with about 72%. The biggest part comes from intake of fruit (34%), followed by intake of milk (24%) and cereals (20%). The contribution of radioactivity in water, taken from previous studies is also considered. Even the maximum possible value of the annual dose for infants still doesn't exceed the recommended limit of 1 mSv.