Radioactivity measurements and dosimetric evaluation in meat of wild and bred animals in central Italy

Radiological impact of 226Ra, 232Th and 40K in fodders from Penang, Malaysia

The plant acts as an important route for the transfer of radionuclides from the soil to animals, leading to the transfer of radiation to human food products such as beef and milk. Therefore, the level of radioactivity in fodder plays a crucial role in deciding whether cattle may be allowed to graze in a certain area. In this study, the activities of 226Ra, 232Th and 40K were measured via gamma-ray spectrometry on different fodder samples, including napier leaves, rice straw, corn stalks, guinea grass, mixed pasture, palm oil leaves and palm kernel collected from Penang, Malaysia. Theoretical calculations were also conducted to estimate the levels of these radionuclides in caw's products (beef and milk), as well as their potential radiological impact on local consumers. On average, the annual effective dose due to ingestion of radionuclides in milk was 11.39 μSv y-1, whereas in beef it was 5.63 μSv y-1. These values are significantly lower than the worldwide average of 290 μSv y-1. Research confirmed that farmers' usage of the aforementioned feeds did not cause any radiation-related health risks.

Recent progresses in analytical method development for 210Pb in environmental and biological samples

As a decay product of uranium series, 210Pb spreads widely in the nature and imposes strong radiological and chemical toxicity. It is vital to establish reliable and efficient radioanalytical methods for 210Pb determination to support environment and food radioactivity monitoring programs. This article critically reviews analytical methods developed for determining 210Pb in environmental and biological samples, especially new development in recent years. Techniques applied throughout different analytical steps including sample pretreatment, separation, purification, and detection are summarized and their pros and cons are discussed to provide a holistic overview for 210Pb environmental and biological assay.

High-levels of toxic elements and radioactivity in an abandoned sulphur mine: Insights on the origin and associated environmental concerns

Natural fibrous epsomite crystals containing high amounts of toxic and radioactive elements have recently been discovered in the abandoned sulphur mine of Perticara (Italy). In the present study, all the different matrices that characterize the Perticara mine (air, water, host-rock, minerals, and bitumen) were sampled and investigated employing a multi-analytical approach to define the distribution and origin of these hazardous elements. Water samples showed high Al, Fe, Pb, Mg, and Mn content but not radioactive elements. The bitumen sample showed a higher amount of 210Po and 210Pb (0.12 Bq/g and 0.11 Bq/g, respectively), compared to the host-rock and fibrous sericolite samples, but lower than fibrous epsomite crystals (210Po 5.59 Bq/g; 210Pb 5.93 Bq/g). A high 222Rn concentration was also detected in the tunnels and it is likely the source of both 210Po and 210Pb, which are in radioactive equilibrium, especially in epsomite. This latter mineral, being capable of capturing 210Po and 210Pb, can be used as a helpful mineral indicator for the presence of radioactive elements in similar environmental conditions. Moreover, our results also highlight a slight anomaly in the 40K and 226Ra content of the host-rock, probably derived from the evaporitic sediments of the rock succession. The current risk for humans linked to the mine environment is minor since the activity of the mine ended several decades ago. However, the results of this study must be taken into serious consideration for any future development of this area (e.g., industrial archaeology, farming, educational, scientific and touristic purposes), and represent the basis for the calculation of radiotoxicity and dose assessment, which is fundamental for the correct and safe management of the mining environment and neighbouring areas.

Could soluble minerals be hazardous to human health? Evidence from fibrous epsomite

From a toxicological point of view, particulates and fibres with high solubility in water and/or in biological environments have not been considered in detail and the knowledge to date in this area is very scarce. In this study, the water-soluble natural epsomite fibres from Perticara Mine (Italy) were investigated using SEM-EDS, XRPD, ICP-AES and alpha spectrometry measurements which were combined and integrated to characterise the fibres' morphology, crystal chemistry and mineralogy. The morphological and morphometric results showed that most of the fibres are of inhalable size (D_ae 5.09 μm) and can be potentially adsorbed from all parts of the respiratory tract. Chemical analysis reveals significant amounts of toxic elements (As, Co, Fe, Mn, Ni, Sr, Ti, Zn) and surprisingly high contents of radioactive isotopes (²¹⁰Po and ²²⁸Th) in epsomite crystals, making the inhalation of these fibres potentially hazardous to human health. Through this study, we want to focus on soluble minerals, such as epsomite, which can be present in both natural and anthropic environments and have never been considered from the point of view of their potential hazard.

Determination of natural radioactivity in products of animals fed with grass: A case study for Kars Region, Turkey

In this research, the activity concentrations of 40 K, 232Th and 226Ra in 41 grass samples collected from Kars region, Turkey, were determined using gamma ray spectrometry. Natural radioactivity concentrations in animal food products were calculated based on activity concentrations of these radionuclides in pasture-grass samples and dry-grass consumption of animals. The average annual effective dose from these radionuclides for local consumers due to indirect ingestion of cow milk, sheep milk, poultry, mutton and beef consumption have been calculated as 9.01, 0.24, 1.76, 0.38 and 5.25 µSv y-1, respectively. Furthermore, the calculated average annual effective dose values for adults are within the values found in other countries worldwide. These results show that animal products can be safe for human consumption in terms of radiation exposure due to the natural radionuclides studied.

Public ingestion exposure to 226Ra in Ramsar, Iran

Ramsar, in the north of Iran by the Caspian Sea, has been known for the highest natural radiation background on Earth due to the local geology and hydrogeology. The residents and visitors use the hot springs that distribute the natural radionuclides especially ²²⁶Ra and its decay products in the areas. Many studies have been undertaken to measure the absorbed dose rate in Ramsar's air, however, no survey has been done to assess public internal exposure from ingestion of natural radionuclides, such as, a broad survey for ²²⁶Ra was conducted in foodstuffs and drinking water. This study presents the results of public annual activity intake (Bq) and effective dose (μSv) from ingestion of ²²⁶Ra in foodstuffs and drinking water in Ramsar city. The total mean annual intake for adults was found to be 24.8 Bq. The annual average effective dose due to ingestion exposure to ²²⁶Ra was found to be 6.9 μSv for adults that were slightly more than the estimated global averages reported by UNSCEAR, 2000 (6.3 μSv). The contribution of drinking water and foodstuffs represent respectively about 30% and 70% of the total mean annual effective dose due to ²²⁶Ra. The highest effective dose from ingestion of ²²⁶Ra for adults was estimated to be 80.6 μSv y^-1. Based on the results of this study, even with the largest ²²⁶Ra value in our survey, maximum annual effective dose due to consumption of foodstuffs and drinking water for children was 164.2 μ b Sv y^-1.

Analytical study of 226Ra activity concentration in market consuming foodstuffs of Ramsar, Iran

BACKGROUND

Ramsar, a city of Iran located on the coast of the Caspian Sea, has been considered to be enormously important due to its high natural radioactivity levels. People living in High Level Natural Radiation Areas (HLNRAs) have been exposed by several sources, one of which could be foodstuff. However, many studies have been carried out to measure the environmental radioactivity in Ramsar, but no survey has been conducted in all stapled consumed foods yet. This study was dedicated to determine ²²⁶Ra activity concentration in the daily diets of Ramsar residents as a probable exposure.

METHODS

Approximately 70 different market samples were collected during the four seasons based on the daily consumption patterns of residents which have the highest consumption and their availability in the seasons. All samples, after washing, drying and pretreatment, were analyzed for ²²⁶Ra radionuclide determination by α-spectrometry.

RESULTS

The mean radioactivity concentration of ²²⁶Ra ranged between 7 ± 1 mBq Kg^-1 wet weight in meat, and 318 ± 118 mBq Kg^-1 for tea dry leaves. The ²²⁶Ra activity concentrations in collected samples varied from below the minimum detectable activity up to 530 ± 30 mBq Kg^-1. To compare the results with United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) reference values, the ²²⁶Ra activity concentrations concluded from the results appear to be higher in milk, chicken and eggs and less in grain products, vegetables, fruits and fish products. These results indicate that no significant ²²⁶Ra contamination is present in market foodstuffs and provide reference values for the foodstuffs in Ramsar.

CONCLUSIONS

Of the total daily dietary ²²⁶Ra exposure from market consuming foodstuffs for adults in Ramsar, the largest percentage was from wheat. The residents consuming wheat and manufacturing wheat products such as bread, pasta, porridge, crackers, biscuits, pancakes, pies, pastries, cakes, cookies, muffins, rolls, doughnuts, breakfast cereals and so on may receive an elevated dose in the diet. In conclusion, with regards to presence of ²²⁶Ra in foodstuffs it is necessary to monitor regularly the activity of ²²⁶Ra in foodstuffs including market and local foods.

Radioactivity levels in the mostly local foodstuff consumed by residents of the high level natural radiation areas of Ramsar, Iran

Among High Level Natural Radiation Areas (HLNRAs) all over the world, the northern coastal city of Ramsar has been considered enormously important. Many studies have measured environmental radioactivity in Ramsar, however, no survey has been undertaken to measure concentrations in the diets of residents. This study determined the ²²⁶Ra activity concentration in the daily diet of people of Ramsar. The samples were chosen from both normal and high level natural radiation areas and based on the daily consumption patterns of residents. About 150 different samples, which all are local and have the highest consumption, were collected during the four seasons. In these samples, after washing and drying and pretreatment, the radionuclide was determined by α-spectrometry. The mean radioactivity concentration of ²²⁶Ra ranged between 5 ± 1 mBq kg^-1 wet weight (chino and meat) to 725 ± 480 mBq kg^-1 for tea dry leaves. The ²²⁶Ra activity concentrations compared with the reference values of UNSCEAR appear to be higher in leafy vegetables, milk and meat product. Of the total daily dietary ²²⁶Ra exposure for adults in Ramsar, the largest percentage was from eggs. The residents consuming eggs from household chickens may receive an elevated dose in the diet.

Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet

To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring.

Assessment of radiological risk for marine biota and human consumers of seafood in the coast of Qingdao, China

This paper reports the levels of (226)Ra, (232)Th, (40)K and (137)Cs in the edible parts of 11 different marine species collected from the Qingdao coast of China. The activities of (226)Ra, (232)Th and (40)K ranged from 0.08±0.03 to 1.65±0.60 Bq kg(-1) w.w., 0.09±0.02 to 1.44±0.10 Bq kg(-1) w.w., 26.89±1.25 to 219.25±5.61 Bq kg(-1) w.w., respectively. Artificial (137)Cs was undetectable or close to the detection limit in the biota sampled. To link radioactivity to possible impact on health, we calculated radiation doses to both the marine biota and human beings. We showed that doses in all cases were dominated by naturally occurring (40)K and that (137)Cs doses were negligible compared with (40)K-derived doses. The total doses to marine biota ranged between 16.55 and 62.41 nGy h(-1) among different biota species, which were below the benchmark level of aquatic organism. The committed effective dose to humans through seafood consumption varied from 10.55 to 36.17 μSv y(-1), and the associated lifetime cancer risks ranged from 5.93E-05 to 9.49E-05 for different age and gender groups. Both the dose and cancer risk to humans were at the acceptable range. Despite the significant amount of radionuclides released as a result of the Fukushima accident, their impact on the seafood in Qingdao coast appears to be negligible based on our measurements of concentrations of radionuclide activity and internal dose estimates.