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Composition of Fracking Water
Published in Frank R. Spellman, Hydraulic Fracturing Wastewater, 2017
Before presenting a detailed discussion of the major chemical constituents that make up hydraulic fracking fluids currently in use it is important to briefly discuss naturally occurring radioactive material (NORM) that could be involved in the fracking process. Some soils and geologic formations contain low levels of radioactive material. This naturally occurring radioactive material emits low levels of radiation to which everyone is exposed on a daily basis. Radiation from natural sources is also referred to as background radiation. Other sources of background radiation include radiation from space and sources that occur naturally in the human body. This background radiation accounts for about 50% of the total exposures for Americans. Most of this background exposure is from radon gas encountered in homes (35% of the total exposure). The average person in the United States is exposed to about 360 millirem (mrem) of radiation from natural sources each year (a mrem, or 1/1000 of a rem, is a measure of radiation exposure) (RRC, 2012). The other 50% of exposures for Americans comes primarily from medical sources. Consumer products and industrial and occupational sources contribute less than 3% of the total exposure (NCRP, 2009).
Radiation protection and safety
Published in Ken Holmes, Marcus Elkington, Phil Harris, Clark's Essential Physics in Imaging for Radiographers, 2021
The likelihood of this effect occurring is governed by the laws of probability and the chance of it occurring is therefore directly related to the dose of ionising radiation received. The guiding principles arising from this probability-related effect are two fold:There is no ‘threshold’ limit below which a stochastic effect cannot occur. However, the greater the dose received, the greater the risk of the effect occurring. It therefore follows that if we calculate dose equivalent limits for the radiations at our disposal, we can use them to calculate the statistical risk that an individual runs by exceeding that limit.While the chance of a cancer effect occurring may be probability-related, the severity of any resultant effect will not be. We know from statistical records that populations which are exposed to ionising radiations (over and above natural background radiation which everyone receives to a lesser or greater extent, depending largely on where they live) have a greater risk of developing cancer. However, if the disease is contracted, its severity will not be related to the radiation dose received. There is a much reduced risk of developing a cancer following a low-dose chest X-ray than there would be following a high-dose examination, such as a CT scan of the chest. However, if a cancer did result from either examination, its rate and extent of progression would be related to the genetic make up of the individual, not the dose of radiation which may have caused it.
Physical and psychological health hazards and risk control
Published in Phil Hughes, Ed Ferrett, Introduction to Health and Safety in Construction, 2015
The Ionising Radiations Regulations have set two action levels above which remedial action, such as fitting sumps and extraction fans, has to be taken to lower the radon level in the building. The first action level is 400 Bq/m3 in workplaces and 200 Bq/m3 in domestic properties. At levels above 1000 Bq/m3, remedial action should be taken within 1 year. The average background radiation in the UK is 2.4 mSv per year. Background radiation levels are much higher elsewhere in the world – 260 mSv have been recorded in Iran.
Spatial distribution modeling of radiometric analysis and radiation dose estimations in drinking water and soil samples from Siirt city in Türkiye
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Nevzat Damla, Ahmet Altun, Cafer Mert Yesilkanat, Halim Taskin, Ayhan Kara, Umit Isık
It is well known from previous studies that humans are subjected to radiation from many sources (Garba et al. 2019; Omeje et al. 2018: Alomari et al. 2019; Rani et al. 2021; Saleh et al. 2015; UNSCEAR 2000, Saleh et al. 2013). Some of these sources are natural radioactive materials and their decay products formed within the atmosphere and on Earth as well as the radionuclides produced for various applications. Background radiation could reach high values when the environment is contaminated by artificial activities, whose sources of radiation are medical, industrial sources and nuclear activities, and natural activities, which contain both cosmic radiation and environmental radioactivity. Deposit materials may come from the surface soil through processes, such as rock decomposition and soil formation. They can also seep into the groundwater system, pollute it, and give rise to contamination distant from the source (Mohammed and Mazunga 2013). This highlights the importance of environmental protection measures and how important it is to limit the human impact on our planet.
A study of environmental radioactivity measurement of selected Kaolin mining fields in Kwara, Nigeria
Published in Cogent Engineering, 2022
Mojisola Rachael Usikalu, Muyiwa Michael Orosun, Akinwumi Akinpelu, Kayode John Oyewumi
People’s exposure to ionizing radiation has become a growing source of public concern because of its associated health effects such as cancer (Ajibola et al., 2021; Joel et al., 2019; Orosun et al., 2020a). The background radiation is made up of radioactive nuclei that are found in air, soil and water either naturally or as a result of human activities. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) estimates that the global average human exposure from natural radiation sources is 2.4 mSvy−1, with natural sources of terrestrial and cosmic origin accounting for 82% of this amount (Oyeyemi et al., 2017; United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). The terrestrial component is made up of long-lived radionuclides in the earth’s crust, whereas the cosmic component is made up of cosmic rays from space. Furthermore, man-made sources such as nuclear disasters, reactor accidents, nuclear testing and the use of technical items have an impact on background radiation levels in a region. Although natural radiation is the primary source of the world’s population’s external dosage, the potential dangers of increased or heightened levels of radioactive chemicals in air, water and soil are usually considered a public health concern. As a result, environmental radioactivity measurements are routinely carried out by researchers all over the world in order to ascertain the nationwide background radiation levels.
Of fission and fallout: New Zealand in the nuclear age
Published in Journal of the Royal Society of New Zealand, 2021
The concentrations of Cs-137 in soil at each island were translated into annual doses received by residents. On the basis of a survey of dietary intake of a Rongelap community, estimates of Cs-137 dietary intake were made for both a current diet (18% of foods obtained from locally produced foods) and a more traditional diet (75% of food obtained from local sources). For the 18% local foods diet internal exposure from dietary intake exceeded external exposure from Cs-137 in soil by about a factor of 5, and for the 75% local foods diet, by a factor of about 20. For the 18% diet virtually all atolls and island groups other than Bikini island of Bikini atoll and the northern Rongelap group of islands would give residents dose rates of less than 1 mSv/y. A small number of individual islands of northern atolls, however, exceed I mSv/y from external radiation alone. For the 75% diet average resident dose rates would exceed 1 mSv/y for the southern Rongelap group of islands, Bikini atoll, Northern Enewetak and Rongerik atolls. Common natural background radiation dose rates are in the range 1–13 mSv/y. The results of the major study were not readily accepted (McEwan et al. 1997)