The nickname "Cancer Valley" was apparently first applied to the Kanawha Valley by Mother Jones magazine. The term expressed the belief that cancer rates in the middle and upper valley were abnormally high, presumably due to the concentration of industry, including chemical plants, in the area of Charleston, South Charleston, and neighboring cities of West Virginia. "Cancer Valley" was an apparent word play on the name "Chemical Valley," once promoted by regional industry and local municipalities and reflecting the Kanawha Valley's world leadership in the mid-20th century chemical industry.

Those believing that the "Cancer Valley" reputation was justified cited a State Health Department study showing cancer deaths in the Charleston neighborhood nearest to the chemical plants to have been much higher than average, as well as an estimate by the National Cancer Institute that 80 percent of cancer deaths had environmental causes. Skeptics countered that environmental causes include lifestyle factors, especially diet and smoking, which together account for a large majority of cancers. The unfortunate nickname had fallen largely out of use by the turn of the 21st century, by which time the valley’s chemical industry had experienced a severe decline.