{"title":"Radium levels in Brazil nuts: A review of the literature.","authors":"Christian Koeder, Markus Keller","doi":"10.1111/nbu.12717","DOIUrl":null,"url":null,"abstract":"<p><p>Brazil nuts are well known for their extraordinarily high selenium content. For this reason, they are frequently recommended as a kind of natural selenium 'supplement', particularly for certain population groups such as vegetarians and vegans in regions with low soil selenium levels. Typically, an intake of one or two Brazil nuts per day is recommended. Brazil nuts, however, also stand out from other nuts in terms of their high (albeit highly variable) radium content. The radium isotopes Ra-226 and Ra-228 emit alpha- and beta-radiation, with this type of radiation being particularly harmful when ingested. Consequently, it is important to consider radium levels in Brazil nuts before formulating recommendations for a long-term, daily intake of these nuts. To date, however, no comprehensive overview of radium levels in Brazil nuts has been published. Therefore, a literature review without time or language restrictions was conducted, including unpublished original data from Germany. The literature review (including the German data) indicated mean Ra-226 and Ra-228 levels of 49 (range: 17-205) mBq/g and 67 (range: 12-235) mBq/g, respectively. Assuming a consistent daily intake of one or two Brazil nuts, this would result in an effective dose of ~88-220 μSv/year. This level of exposure appears to be neither clearly harmful nor clearly harmless. As increased radioactivity exposure (at least at higher doses) is associated with increased cancer risk, randomised controlled trials assessing the effect of Brazil nuts on cancer risk biomarkers are needed.</p>","PeriodicalId":48536,"journal":{"name":"Nutrition Bulletin","volume":" ","pages":""},"PeriodicalIF":2.7000,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nutrition Bulletin","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1111/nbu.12717","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"NUTRITION & DIETETICS","Score":null,"Total":0}
引用次数: 0
Abstract
Brazil nuts are well known for their extraordinarily high selenium content. For this reason, they are frequently recommended as a kind of natural selenium 'supplement', particularly for certain population groups such as vegetarians and vegans in regions with low soil selenium levels. Typically, an intake of one or two Brazil nuts per day is recommended. Brazil nuts, however, also stand out from other nuts in terms of their high (albeit highly variable) radium content. The radium isotopes Ra-226 and Ra-228 emit alpha- and beta-radiation, with this type of radiation being particularly harmful when ingested. Consequently, it is important to consider radium levels in Brazil nuts before formulating recommendations for a long-term, daily intake of these nuts. To date, however, no comprehensive overview of radium levels in Brazil nuts has been published. Therefore, a literature review without time or language restrictions was conducted, including unpublished original data from Germany. The literature review (including the German data) indicated mean Ra-226 and Ra-228 levels of 49 (range: 17-205) mBq/g and 67 (range: 12-235) mBq/g, respectively. Assuming a consistent daily intake of one or two Brazil nuts, this would result in an effective dose of ~88-220 μSv/year. This level of exposure appears to be neither clearly harmful nor clearly harmless. As increased radioactivity exposure (at least at higher doses) is associated with increased cancer risk, randomised controlled trials assessing the effect of Brazil nuts on cancer risk biomarkers are needed.
期刊介绍:
The Nutrition Bulletin provides accessible reviews at the cutting edge of research. Read by researchers and nutritionists working in universities and research institutes; public health nutritionists, dieticians and other health professionals; nutritionists, technologists and others in the food industry; those engaged in higher education including students; and journalists with an interest in nutrition.