Fluorine Contens of the Underground Waters in the Choong Nam Province (I).-the town ONYANG-

忠南地區 地下水 中의 弗素含量 調査에 關한 硏究 (I)-溫陽邑內

66 samples of underground waters at the town Onyang were collected and analyzed from August 19 to November 5, 1969. Fluorine more than 1.0 mg/l is contained in the under ground waters in the region 0.9 km away from the Onyang hot springs, fluorine more than 0.3 mg/l in the waters in the region 1.2 km away from the hot springs, and 0.04-0.29 mg/l fluorine in the waters in the region from 1.2 km to 3.9 km away from the hot springs. It is advisable that the residents in their teeth growing ages must not drink the underground waters in the region 1.2 km away from the hot springs because the waters cause dental trouble (mottled teeth) and they may drink the waters in the region from 1.2 km to 3.9 km away from the hot springs for the fluoridation of their teeth. It is reasonable to suppose that the high fluorine contents of the underground waters are caused mainly by the contamination of the hot spring waters in which fluorine and calcium in rock are dissolved, in the region 1.2 km away from the hot springs, and that the waters in the region from 1.2 km to 3.9 km away from the hot springs contain much fluorine produced by the decomposition of organic substances.

忠南 溫陽邑內의 地下水中의 弗素含量을 1969年 8月 19日부터 同年 11月 5日까지 사이에 測定하였다. 溫泉에서부터0.9km 以內의 地域內에 있는 地下水 中에는 1.0mg/l以上의 $F^{-1}$이 含有되어 있으며,1.2km 以內의 地域內에 있는 것에는 0.3mg/l 以上의 $F^{-1}$이 含有되어 있어 이들 地下水를 齒牙 生長期에 飮料水로 常用時에는 班狀齒의 原因이 되므로 住意해야 되며, 溫泉에서 1.2km∼3.9km 以內의 地域內에 있는 地下水에는 0.04∼0.29mg/l의 $F^{-1}$을 含有하고 있어서 모두 치아우식억제효과를 얻을 것이다. 溫泉 附近에서는 溫泉水에 岩石中의 $F^{-1}$이 $Ca^{+2}$과 함께 溶出되어, 이들 溫泉水가 地下水에 混入된다고 보여진다. 溫泉에서 먼 距離의 地下水에는 有機物의 分解에 基因하는 $F^{-1}$도 含有되어 있다고 보여진다.