Occupational dose from natural radionuclides in phosphate fertilizers

Abstract

In this investigation the occupational exposure of single persons due to the gamma radiation of the natural radionuclides in rock phosphates and phosphate fertilizers and their contribution to the population dose in the FRG has been determined. The exposure rates in the working fields production, transport, loading and storage or rock phosphates and phosphate fertilizers and due to their application in agriculture have been measured by means of scintillation dose rate meters or LiF-thermoluminescence dosemeters or have been estimated from specific activities. Mean additional exposure rates of 2--26 muR/h, with local maximum values up to 190 muR/h, were observed. From these values, together with statistical data for the number of occupied persons and annual working times in the various working fields, the mean and maximum annual dose of individuals and the contribution to the mean population dose have been estimated. The results show that a maximum annual dose to individuals from 0.4 mrem/y (agriculture) up to 45 mrem/y (production plants or storehouses) can occur. The corresponding mean annual doses are 0.05--20 mrem/y. The contribution of the occupational radiation exposure due to rock phosphates and phosphate fertilizers to the mean population dose is 174 man . rem/y related to whole body. To this, fertilizer production contributes 40 man . rem/y, transport and loading 45 man . rem/y, agricultural storehouses 31 man . rem/y, and agriculture 58 man . rem/y. Altogether, this investigation shows that an occupational radiation exposure of individuals may occur which corresponds to the mean terrestrial radiation exposure in the FRG. The contribution of the occupational collective doses due to phosphates to the population dose, however, is negligibly small.

Environmental impact of phosphate mining and beneficiation: review

“…Concentrations of 226 Ra in phosphate rock are reported to vary, covering a range of 1-2 Bq/g. [25][26][27][28][29] Most of the 226 Ra in the ore ends up in the waste phosphogypsum during the production of phosphate fertilizers. The concentration of 226 Ra in these wastes is reported to be nearly 1Bq/g.…”

Structural and luminescent characterisation of uraniferous fluorapatite and haematite associated with phosphatic rocks of the Bijawar group in Sagar District, Madhya Pradesh (India)

“…Uranium being radiologically and chemically toxic is a big environmental hazard and earlier studies have revealed that people living in phosphatic mining zone had higher concentration of uranium in their blood rather than the people staying in urban dwelling (Menzel 1968;Philip et al 1979;Cevik et al 2010;Albedri et al 2014;Sahu et al 2014).…”

Dose de radiação ionizante decorrente do uso de fertilizantes agrícolas

“…Estudo realizado na antiga República Federal Alemã indica que os fertilizantes fosfatados contêm radionuclídeos naturais com atividades específicas que excedem em até 50 vezes as atividades específicas médias de solos comuns (Philipp et al, 1979). Pode também dobrar o conteúdo de urânio e rádio no solo o que significa que poderá dobrar esse conteúdo nos nossos ossos (Eisenbud, 1987).…”