Optimisation and Validation of a Multi-matrix Ultrasensible Radiochemical Method for the Determination of Radiostrontium in Solid Foodstuffs by Liquid Scintillation Counting

Detection and measurement of radioactive substances in water and food: a narrative review

Contamination of food and water with radioactive substances is a serious health problem. There are several methods to detect and measure radioactive materials, some of which have been developed in recent years. This paper aims to discuss the methods of detecting and measuring radioactive substances in food and water. The principles and the advantages and disadvantages of each method have been discussed. The results showed that some of these methods, such as spectrometry γ-ray high-purity germanium, portable radon gas surveyor SILENA, RAD7, and inductively coupled plasma mass spectrometry, have a higher sensitivity for detection and measurement. The spectrometry γ-ray high-purity germanium method has attracted more attention than other methods because it can measure a wide range of radionuclides with high resolution.

Fast and Sensitive Radiochemical Method for Sr-90 Determination in Food and Feed by Chromatographic Extraction and Liquid Scintillation Counting

Strontium-90 (Sr-90) contamination in food is a major public health issue. Several radiochemical methods are available for the determination of Sr-90. However, the application of these procedures is not focused on solid foods, but only on liquid (milk, water, etc.) and environmental matrices, and they were not fully validated. The aims of this work were to establish and validate a fast, sensitive method for the determination of Sr-90 in solid food matrices such as meat and dairy products, seafood, vegetables, and animal feed, using a specific resin for extraction and ultra-low-level liquid scintillation counting for detection. The method was optimised and validated according to relevant legislation. Good analytical performance was obtained, including high specificity and linearity together with low measurement uncertainty (13.1%). The minimal detectable activity was 11 mBq kg−1, and the mean repeatability (CV%) and recovery values were 10.7% and 100.1%, respectively. These parameters assured method applicability for official food safety controls. The method was applied to reference materials and submitted to proficiency test round to confirm its reliability for Sr-90 quantification in solid foodstuffs and feed. The newly established method may be broadly applicable to complex matrices.

The analytical determination of polyphosphates in food: A point-to-point comparison between direct ion chromatography and indirect photometry

Being an indirect approach, the standard method for the determination of polyphosphates (PPs) in food maybe characterized by high variability which can lead to significant errors in the final measurement. In this study, this method was validated and then compared to the ion chromatography-based approach. Method trueness and measurement uncertainty resulted comparable, while the precision of ion chromatography approach was higher. No "false positive" responses were obtained from ion chromatography analysis, while indirect photometry may cause "false positive" results (5% of analyzed samples). Regarding "false negative" results, this possibility maybe verified for all food types tested and for seafood when using indirect photometry and ion chromatography, respectively. The percentages of "false negative" samples were equal to 23.3% for indirect photometry and 10% for ion chromatography. In conclusion, the indirect photometry is a reliable method especially as "screening technique", while ion chromatography maybe used as a confirmatory technique, successfully.