Evaluation of risk due to chronic low dose ionizing radiation exposure on the birth prevalence of congenital heart diseases (CHD) among the newborns from high-level natural radiation areas of Kerala coast, India

Background The human population residing in monazite bearing Kerala coast are exposed to chronic low dose and low dose rate external gamma radiation due to Th232 deposits in its beach sand. The radiation level in this area varies from < 1.0 to 45.0 mGy/year. This area serves as an ideal source for conducting large-scale epidemiological studies for assessing risk of low dose and low dose rate radiation exposure on human population. The areas with a dose level of ≤1.50 mGy/year are considered as normal level natural radiation areas (NLNRAs) and areas with > 1.50 mGy/year, as high level natural radiation areas (HLNRAs). HLNRAs were further stratified into three dose groups of 1.51-3.0 mGy/year, 3.01-6.00 mGy/year and > 6.0 mGy/year. The present study evaluates the effects of chronic low dose radiation (LDR) exposure on the birth prevalence of Congenital Heart Diseases (CHD) among the live newborns monitored in hospital based prospective study from NLNRAs and HLNRAs of Kerala coast, India. Methodology Consecutive newborns were monitored from two hospital units located in the study area for congenital malformations. Referred CHD cases among the newborns screened were confirmed by conducting investigations such as pulse oximetry, chest X-ray, electrocardiogram and echocardiogram etc. Results Among the newborns screened, 289 CHDs were identified with a frequency of 1.49‰ among 193,634 livebirths, which constituted 6.03% of overall malformations and 16.29% of major malformations. Multiple logistic regression analysis suggested that the risk of CHD among the newborns of mothers from HLNRAs with a dose group of 1.51-3.0 mGy/year was significantly lower as compared to NLNRA (OR = 0.72, 95% CI: 0.57-0.92), whereas it was similar in HLNRA dose groups of 3.01-6.00 mGy/year (OR = 0.55, 95% CI: 0.31-1.00) and ≥ 6.0 mGy/year (OR = 0.96, 95% CI: 0.50-1.85). The frequency of CHDs did not show any radiation dose related increasing trend. However, a significant (P = 0.005) reduction was observed in the birth prevalence of CHDs among the newborns from HLNRA (1.28‰) as compared to NLNRA (1.79‰). Conclusion Chronic LDR exposure did not show any increased risk on the birth prevalence of CHDs from high-level natural radiation areas of Kerala coast, India. No linear increasing trend was observed with respect to different background dose groups. The frequency of CHD was observed to be 1.49 per 1000 livebirths, which was similar to the frequency of severe CHD rate reported elsewhere in India and was much less than the reported frequency of 9 per thousand.

Consideration of the contribution of the natural background component during individual control of radiation doses to personnel

When ensuring radiation safety in the Russian Federation, there is a principle of separate independent assessment of doses from natural, medical, emergency and technogenic exposure. In practice, it is not always possible to comply with this principled approach. The established dose limits are related only to man-made radiation during normal operation of sources of ionizing radiation. However, during the formation of regional and federal databases on individual doses of personnel exposure, information is entered not on technogenic exposure, but on industrial exposure, that is, without subtracting the natural radiation background. The natural component of the individual dose at low radiation doses is quite significant. Failure to its subtraction leads to an overestimation of the individual dose of external exposure of personnel. Difficulties arise in the implementation of the subtraction of the natural radiation background: 1) in what cases it is necessary to subtract the background, 2) what value to choose for the subtracted background, 3) what method to measure the background, 4) at what stage of processing the measurement information to subtract the background. This article proposes a method for solving the problem of subtracting the natural background radiation from the values of individual doses of external exposure to personnel based on results of individual dosimetric control. Using the example of the city of St. Petersburg, the natural background radiation was measured by the thermoluminescent method of individual dosimetry at 50 control points for three consecutive years (2018-2020). To measure the natural background, we used individual thermoluminescent dosimeters of the same type as those used to measure individual equivalents of external radiation doses to personnel. The choice of using the thermoluminescent method as a predominant one for adjusting the average doses of external radiation from technogenic sources of ionizing radiation when subtracting the natural component of the dose has been substantiated. Comparison of official data on personnel exposure doses with the data obtained as a result of our own measurements is made. Recommendations are given on the use of the obtained values of the average natural radiation background in the formation of regional and federal databases on individual doses of personnel exposure.

The Radiological Background Inside and Outside the Libyan Iron and Steel Company in Misurata City, Northwest of Libya

Radioactive background is very important with regard to the exposure of the population to radiation, many countries of the world measure the rate of exposure caused by natural radiation for different purposes, where radioactive pollution represents an important problem as a result of the spread and the frequent use of radioactive materials in different applications, such as medicine, agriculture, industry, and others, and some industrial facilities in the city of Misurata like Libyan Iron Company use some techniques that depend on radioactive sources. In this study, over a whole year with its four seasons, the levels of radiation background were evaluated in the area surrounding the Libyan Iron and Steel Company in the Qasr Ahmed region in Misurata city and within the company’s. It is measured for primary and secondary directions for a distance of 8 km. The radiation levels outside and inside the company’s perimeter were within the natural limits of the radiation background in the area, radiation levels do not different between the monitoring points that were measured within the company’s borders from those that were measured in the area surrounding the company. The radiation levels are not affected by the measurement season, and therefore that the obsession of radioactive contamination that some people have is unfounded and that the situation from this aspect is reassuring.

Review on monitoring natural and environmental radiation and its potential from mining products

Monitoring of natural radiation in Indonesia has been carried out by various parties, from researchers, academics at universities to special agencies tasked with handling this matter, such as the National Nuclear Energy Agency (Batan) and the Nuclear Energy Supervisory Agency (Bapeten). Batan through the Center for Radiation Safety and Metrology Technology (PTKMR) is in charge of monitoring natural radiation at the national level. The purpose of this paper is to review the monitoring of natural and environmental radiation in Indonesia and the potential of mining products as a source of natural radiation. The mining products that will be reviewed in this paper are natural uranium and thorium which are usually found in several mines, such as tin mines and others.

Review on monitoring natural and environmental radiation and its potential from mining products

Monitoring of natural radiation in Indonesia has been carried out by various parties, from researchers, academics at universities to special agencies tasked with handling this matter, such as the National Nuclear Energy Agency (Batan) and the Nuclear Energy Supervisory Agency (Bapeten). Batan through the Center for Radiation Safety and Metrology Technology (PTKMR) is in charge of monitoring natural radiation at the national level. The purpose of this paper is to review the monitoring of natural and environmental radiation in Indonesia and the potential of mining products as a source of natural radiation. The mining products that will be reviewed in this paper are natural uranium and thorium which are usually found in several mines, such as tin mines and others.

Results of the 20-year period of functioning of the Federal Databank on the natural radiation doses to the population of the Russian Federation

This study is focused on the analysis of the results of the functioning of the Federal Databank on the doses to the public of the Russian Federation from natural and man-made modified radiation background as a part of Joint governmental system of control and accounting of the doses from ionizing exposure in 2001-2020. The mean individual annual effective dose of the public of the Russian Federation from natural sources of ionizing exposure, calculated based on the data from all measurements in 2001-2020, is equal to 3,36 mSv/year. The study includes the analysis of the problems and perspectives of the improvement of the system of the data collection on the levels of exposure of the public of the Russian Federation from natural sources.

Radioecology

Natural radiation arises from many sources, from the unstable atoms within our own bodies and in the materials around us, from the Sun, and even from beyond the Solar System. Additional sources include the legacy of testing nuclear weapons, nuclear waste, and nuclear accidents. All these sources have provided means of dating environmental materials and tracing the movements of substances through land, sea, and air. But ionising radiation also interacts with DNA, which has led to a remarkable range of studies to examine how and how quickly these unstable atoms are accumulated by both humans and biota, and their various effects on both. Providing an overview of the sources, uses and impacts of ionising radiation in the environment, and the frameworks developed to manage exposures to them, this is a valuable reference for graduate students and researchers interested in radioecology, environmental science and radiological protection.