Assessment of cancer risk and radiological effects from 210Po and 210Pb with consumption of wild medicinal herbal plants.

BACKGROUND: Plants' raw materials can accumulate chemical elements, including radioisotopes, to some extent and reflect the region they grow in. Due to their high environmental content and toxicity, natural radionuclides - polonium 210Po and lead 210Pb are the most dangerous radioisotopes for human health. METHODS: 70 raw medicinal herbal materials from 54 popular wild-growing medicinal plant species, most of them included in the European Pharmacopoeia, were collected across three regions. In 210 samples, the activity concentrations of 210Po and 210Pb were determined, and their radiotoxicity and cancer risk were calculated. RESULTS: The results of 210Po and 210Pb activities measured in herbal raw material were from 0.12 mBq g-1 dry weight in the fruits of the common chestnut (Aesculus hippocastanum) to 19.7 mBq g-1 dw in herb of ground elder (Aegopodium podagraria) for 210Po, while for 210Pb ranged from 0.16 mBq g-1 dw to 34.3 mBq g-1 dw in the same plants. There were statistically significant differences between 210Po and 210Pb content in leaves, herbs, flowers, and fruit. The studies indicated that the estimated annual effective radiation dose from Polish medicinal herbs consumption was low, ranging 0.03-105 µSv from 210Po and 0.02-98.2 µSv from 210Pb, while the risk of cancer morbidity and mortality ranged from 10-5 to 10-9. CONCLUSIONS: Consumption of the tested medicinal herbs is safe from the radiological point of view and, based on the predictions related to the calculated risk of cancer, should not increase the probability of its occurrence.

On the radiotoxic 210Po in coffee beans worldwide and the impact of roasting and brewing on its extraction into beverages: from the experiments to 210Po content prediction.

We determined radiotoxic 210Po in roasted coffee beans from different regions worldwide, the beverages, and tried to create the prediction model of 210Po content based on its growth location. Additionally, the experiments on 210Po losses and extraction were performed to describe the actual exposure to 210Po. 210Po concentrations in coffee beans and brews tuned out low (maximally of 0.20 Bq∙kg-1 and 2.31 Bq∙L-1, respectively). We assessed the impact of the roasting process on 210Po content and its losses at a maximum of 56.7%. During infusion experiments, we estimated the extraction of 210Po to the coffee brew at a maximum of 40.6%. The amount of 210Po in the coffee brew depended on the infusion style and water type. We calculated the effective radiation doses from the coffee drink ingestion. Coffee drinking does not contribute significantly to the annual effective radiation dose worldwide.

On the occurrence, origin, and intake of the nuclides, 210Po and 210Pb, in sclerotia of Wolfiporia cocos collected in China.

The dried sclerotium of the fungus Wolfiporia cocos is edible and has medicinal value. This study aimed to understand the accumulation of radioactivity arising from the alpha 210Po, and beta-emitting 210Pb, in the sclerotium's shell and core and assess a potential effective dose for consumers. Sclerotia were collected in the wild and from cultivars in China's Anhui and Yunnan provinces. The mean values of 210Po activity concentration levels were 0.36 Bq kg-1 dry weight in the core and 12.0 Bq kg-1 dw in the shell; 210Pb activities were 0.43 and 9.84 Bq kg-1 dw, respectively. The potential effective radiation doses from core layers (as a major raw material of the sclerotium) ranged from 0.13 to 3.43 µSv kg-1 dw from 210Po decay and from 0.11 to 1.52 µSv kg-1 dw from 210Pb decay. Corresponding values for shell ranged from 0.80 to 42.4 for 210Po and from 0.53 to 13.6 µSv kg-1 dw for 210Pb. In general, the intake of W. cocos sclerotia varies between consumers, but this would not significantly change the effective radiation doses from 210Po and 210Pb isotopes. The consumption thus appears to be safe from a radiological protection point of view.

210Po and 210Pb in King Bolete (Boletus edulis) and Related Mushroom Species: Estimated Effective Radiation Dose and Geospatial Distribution in Central and Eastern Europe.

210Po and 210Pb occur naturally and are the most radiotoxic isotopes of the uranium (U) decay chain. Samples of Boletus edulis and related mushroom species, including B. pinophilus, B. reticulatus, B. luridus and B. impolitus, collected from Poland and Belarus were investigated for the activity concentrations of these isotopes and also for their potential health risk through adult human consumption. The results showed that spatially, the occurrence of 210Po and 210Po was heterogeneous, with activities varying from 0.91 to 4.47 Bq∙kg-1 dry biomass and from 0.82 to 5.82 Bq∙kg-1 db, respectively. Caps and stipes of the fruiting bodies showed similar levels of contamination. Consumption of boletes foraged in Poland could result in exposure to a combined radiation dose of 10 µSv∙kg-1 db from both isotopes. This dose is not significant compared to the total annual effective radiation dose of 210Po and 210Pb (54-471 µSv∙kg-1) from all sources, suggesting that these mushrooms are comparatively safe for human consumption.

Bolete mushroom Boletus bainiugan from Yunnan as a reflection of the geographical distribution of 210Po, 210Pb and uranium (234U, 235U, 238U) radionuclides, their intake rates and effective exposure doses.

This pioneering study aimed to determine the activity concentrations of 210Po, 210Pb and uranium (234U, 235U, 238U) radionuclides in fruit bodies of wild bolete Boletus bainiugan Dentinger and to estimate its edible safety, which may give scientific evidence for the consumption of this species. The analyses were performed using alpha spectrometer after digestion, exchange resins separation and deposition. Measurement data were analysed and interpolation maps reflecting 210Po, 210Pb and uranium (234U, 235U, 238U) geographical distribution in Yunnan province (China) were presented. In addition, from the perspective of food safety, the possible related effective radiation dose to mushrooms consumers were estimated. The results indicated that 210Po, 210Pb and uranium (234U, 235U, 238U) radionuclides contents in B. bainiugan were significantly different with respect to geographical distribution, and their possible intake in a part of the region was considerably higher. A very interesting observation was done according to the values of 235U/238U activity ratio indicating the occurrence of uranium faction from the global fallout of nuclear weapon tests.

The level of 210Pb extraction efficiency in Polish herbal teas and the possible effective dose to consumers.

The article presents the results of a study on the level of 210Pb efficiency extraction in Polish herbal teas as a possible additional source of this radioactive isotope in the human diet. The twelve most popular herbal teas available in Poland and their infusions in filtered and tap water were analyzed as well as 210Pb activity concentrations and effective doses (radiation) were calculated. The highest activity concentration of 210Pb in dried plants was determined in cistus - 35.5 Bq kg-1 dry wt, while the lowest was in milk thistle - 3.25 Bq kg-1 dry wt what gives respectively for cistus 46.1 ± 0.7 and 6.50 ± 0.29 mBq for milk thistle per one tea bag. The extraction efficiencies in the filtered water oscillated from 5.1 ± 0.5 for milk thistle to 27.3 ± 0.8% for cistus, while for the tap water they ranged from 7.3 ± 0.6% for lime to 33.3 ± 2.2% for white mulberry. Based on the study, it was found that the analyzed herbal tea consumption would give a small portion of the annual effective dose of 210Pb received in Poland - the annual effective radiation dose of 210Pb taken with herbal tea infusions (one glass daily) was calculated from 0.08 ± 0.01 to 3.17 ± 0.08 µSv.

On uranium 234U and 238U radionuclides in calcium and magnesium supplements and the potential effective radiation dose assessment to the consumers.

In this survey the concentrations of the radioactive nuclides uranium 234U and 238U were determined in the most popular calcium and magnesium supplements for adults in Poland. It was also investigated whether the supplements contain uranium isotopes and could be a potential source in the human diet and have an influence on the value of effective radiation doses to the consumers. The analyzed calcium and magnesium pharmaceuticals contained organic or inorganic compounds, several of natural origin as mussel's shells, fish extracts, or sedimentary rocks. As results showed, 234U and 238U concentrations in natural origin calcium and magnesium supplements were significantly higher than in other, synthetic ones. The highest 234U and 238U activity concentrations were determined in tablets from mussel's shells. The radiochemical hazard was assessed and the highest annual radiation dose was found in 234U and 238U present in supplements produced from shells or dolomite rock.