Mean cancer mortality rates in low versus high elevation counties in Texas.

There is controversy as to whether low levels of radiation (i.e., < 5 rem) pose a health risk. This brief inquiry compares archived cancer mortality data in counties having relatively low (0-250 feet above sea level), medium (500-1000 feet above sea level), and high (3000+ feet above sea level) elevations also having corresponding greater natural background levels of radiation respectively. Cancer mortality was found to be lowest in the high elevation counties (mean = 58.2) followed by low elevation counties (67.5) and then medium elevation counties (70.4). Statistically significant differences were found between low -high elevations (p = 0.003), and medium - high elevations (p = 0.010), but not between low and medium elevations (p = 0.5). More rigorous research, with an accounting of confounding variables, is indicated.