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
Open Access
- 4 January 2022
- journal article
- research article
- Published by Springer Science and Business Media LLC in Genes and Environment
- Vol. 44 (1), 1-10
- https://doi.org/10.1186/s41021-021-00231-0
Abstract
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. 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. 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‰). 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.Keywords
Funding Information
- Bhabha Atomic Research Centre (NA)
This publication has 34 references indexed in Scilit:
- The global burden of congenital heart disease : review articleCardioVascular Journal of Africa, 2013
- Systematic Review and Meta-analysis of Circulatory Disease from Exposure to Low-Level Ionizing Radiation and Estimates of Potential Population Mortality RisksEnvironmental Health Perspectives, 2012
- Study of stillbirth and major congenital anomaly among newborns in the high-level natural radiation areas of Kerala, IndiaJournal of Community Genetics, 2012
- Cardiovascular Diseases in the Cohort of Workers First Employed at Mayak PA in 1948–1958Radiation Research, 2010
- Radiation-Related Heart Disease: Current Knowledge and Future ProspectsEndocrine, 2010
- Radiation exposure and circulatory disease risk: Hiroshima and Nagasaki atomic bomb survivor data, 1950-2003BMJ, 2010
- Spontaneous frequency of micronuclei among the newborns from high level natural radiation areas of Kerala in the southwest coast of IndiaInternational Journal of Radiation Biology, 2009
- Noninherited Risk Factors and Congenital Cardiovascular Defects: Current KnowledgeJournal of the American College of Cardiology, 2007
- The Chernobyl accident, congenital anomalies and other reproductive outcomesPaediatric and Perinatal Epidemiology, 1993
- Is the incidence of congenital heart defects influenced by the radioactive contamination of the environment due to the accident in chernobyl? — Results from an epidemiological survey on congenital malformations in the South-German State of BavariaEnvironmetrics, 1993