Assessing the Impact of Housing Features and Environmental Factors on Home Indoor Radon Concentration Levels on the Navajo Nation

Abstract

Uranium is naturally found in the environment as a radioactive metal element with high concentrations in the Southwestern US. In this region is the Navajo Nation, which spans approximately 69,930 square kilometers. A decay product of uranium is radon gas, a lung carcinogen that has no color, odor, or taste. Radon gas may pass from soil into homes; and, indoor accumulation has been associated with geographical location, seasonality, home construction materials, and home ventilation. A home and indoor radon survey was conducted from November 2014 through May 2015, with volunteers who reported residence on the Navajo Nation. Home geolocation, structural characteristics, temperature (°C) during radon testing, and elevation (meters) were recorded. Short-term indoor radon kits were used to measure indoor radon levels. 51 homes were measured for indoor radon levels, with an arithmetic mean concentration of 60.5 Becquerels per cubic meter (Bq/m3) (SD = 42.7). The mean indoor radon concentrations (Bq/m3) by house type were: mobile, 29.0 (SD = 22.9); wood, 58.6 (SD = 36.0); hogan, 74.0 (SD = 0.0); homes constructed of cement and wood, 82.6 (SD = 3.5); and homes constructed of concrete and cement, 105.7 (SD = 55.8). A key observation is that house construction type appears to be associated with the mean home indoor radon concentration. This observation has been published in that the basic structural make-up of the home may affect home ventilation and therefore indoor radon concentration levels.

Assessment of indoor radon distribution and seasonal variation within the Kpando Municipality of Volta Region, Ghana

“…The non-uniform distribution observed within the study locality can be attributed to varying radium concentrations across all dwelling locations [ 3 , 8 ]. The measured radon concentration within the Kpando district, in 120 different dwellings, is presented in the form of a range, mean, median, mode, etc.…”

“…Radon is classified as the second main cause of lung cancer after cigarette smoking. It has been characterized as cancerogenic and causes between 3 to 14% of all lung cancer cases reported globally [2][3][4][5]. Literature studies and the International Organization on Radiation Protection have reported that exposure to elevated indoor radon levels in enclosed areas such as dwellings can result in a higher risk of lung cancer incidence among the populace [2,6].…”

Geologic, seasonal, and atmospheric predictors of indoor home radon values

“…Barros-Dios et al [ 34 ] found older homes were primarily constructed of stone in both the exterior and interior of the home and they had significantly higher indoor radon levels, followed by stone-and-brick, and brick alone. Yazzie et al [ 35 ] found that homes constructed of cement and wood and homes constructed of concrete and cement had higher mean indoor radon concentrations than mobile homes and those constructed of wood and cement and wood alone. We need further study to examine the association of home building materials, age of home, and indoor radon levels.…”

Burden of lung cancer attributable to household air pollution in the Chinese female population: trend analysis from 1990 to 2019 and future predictions

“…In terms of residential radon, the overall difference in burden of lung cancer between China and the world increased. In 2019, the Chinese age-standardized mortality and DALYs rates were about 40% higher than the global rates, which may be related to the changes in living and working styles, building types, construction and decorative materials, furniture, and fuel types in recent years 8,32 .…”