Beta emitter radionuclides (90Sr) contamination in animal feed: validation and application of a radiochemical method by ultra low level liquid scintillation counting

⁹⁰Sr is considered as a dangerous contaminant of agri-food supply chains due to its chemical affinity with Calcium, which makes its absorption in bones easy. ⁹⁰Sr accumulation in raw materials and then in final products is particularly significant in relationship to its ability to transfer into animal source products. The radionuclides transfer (¹³⁷Cs and ⁹⁰Sr) from environment to forages and then to products of animal origin (milk, cow and pork meats) was studied and evaluated in different studies, which were carried out in contaminated areas, from Chernobyl disaster until today. In the present work, the development and validation of a radiochemical method for the detection of ⁹⁰Sr in different types of animal feed, and the application of this technique for routinely control activities, are presented. Liquid scintillation counting was the employed analytical technique, since it is able to determine very low activity concentrations of ⁹⁰Sr (<0.01 Bq kg^–1). All samples analysed showed a 90Sr contamination much higher than method detection limit (0.008 Bq kg^–1). In particular, the highest mean activity concentration was registered in hay samples (2.93 Bq kg^–1), followed by silage samples (2.07 Bq kg^–1) and animal feeds (0.77 Bq kg^–1). In fact, all samples were characterized by ⁹⁰Sr activity concentrations much lower than reference limits. This notwithstanding, the necessity to monitor these levels was confirmed, especially considering that ⁹⁰Sr is a possible carcinogen for human

Evaluation and Dietary Exposure Assessment of Selected Toxic Trace Elements in Durum Wheat (Triticum durum) Imported into the Italian Market: Six Years of Official Controls

Durum wheat grains, which are mostly used for the production of pasta and several baked goods, represent a main source of vegetable proteins and calories. Concurrently, many contaminants, including toxic trace elements, may accumulate in them, posing a potential severe hazard to human health. In this context, for official control and food safety purposes, 346 samples of whole durum wheat imported into the Italian market from six countries (Australia, Canada, Kazakhstan, Russia, Turkey, and the United States) during the period 2015–2020 were analysed for cadmium (Cd), lead (Pb), and mercury (Hg) content using inductively coupled plasma mass spectrometry (ICP-MS). All the analysed samples were compliant with Food Agriculture Organization–World Health Organization and European Union regulations. The mean values were 0.0322 and 0.0162 mg kg−1, respectively, for Cd and Pb, while all samples showed levels below the limit of detection (0.004 mg kg−1) for Hg. The results were construed in terms of seasonality, year, and country of production, and compared with reference tolerance values. Confirming previous exposure studies, the obtained data and the dietary intake assessment showed that durum wheat-based products may have a significant impact on exposure to Pb and Cd (20–50%) in the overall population, particularly in more sensitive and/or exposed subgroups (infants, toddlers, and females)

Evaluation of Seasonal Variability of Toxic and Essential Elements in Urine Analyzed by Inductively Coupled Plasma Mass Spectrometry

Human exposure to elements is a process difficult to control and monitor. Studies on this topic usually rely on single spot urine sample to assess exposure, with the risk of ignoring variability over a longer period. In this work, we measured the urinary excretion of toxic and essential elements during 1 year with the overall goal of exploring the variability caused by seasonality on their concentration. Seven participants were recruited, and first morning urines were collected three times for each season, during November, January, April and July. Participants followed the same balanced diet during the week of collection. We then monitored nineteen essential and toxic elements in urines by inductively coupled plasma mass spectrometry. Unsupervised multivariate statistical analysis separated samples collected during summer from the ones collected during other seasons. Twelve elements had a significant seasonal variation (ANOVA test, p < 0.05) and their levels resulted increased during summer. These elements were both contaminants, such as Ni, Hg, Cd and Tl, and essential elements such as Se and Cu. However, none of these elements was detected at toxic concentration. In this study, we point out for the first time the variability of urine element concentration due to seasonality and we propose that the season of collection should be considered when providing urinary reference values of elements

Distinctive Pattern of Serum Elements During the Progression of Alzheimer's Disease

Element profiling is an interesting approach for understanding neurodegenerative processes, considering that compelling evidences show that element toxicity might play a crucial role in the onset and progression of Alzheimer's disease (AD). Aim of this study was to profile 22 serum elements in subjects with or at risk of AD. Thirtyfour patients with probable AD, 20 with mild cognitive impairment (MCI), 24 with subjective memory complaint (SMC) and 40 healthy subjects (HS) were included in the study. Manganese, iron, copper, zinc, selenium, thallium, antimony, mercury, vanadium and molybdenum changed significantly among the 4 groups. Several essential elements, such as manganese, selenium, zinc and iron tended to increase in SMC and then progressively to decrease in MCI and AD. Toxic elements show a variable behavior, since some elements tended to increase, while others tended to decrease in AD. A multivariate model, built using a panel of six essential elements (manganese, iron, copper, zinc, selenium and calcium) and their ratios, discriminated AD patients from HS with over 90% accuracy. These findings suggest that essential and toxic elements contribute to generate a distinctive signature during the progression of AD, and their monitoring in elderly might help to detect preclinical stages of AD