Although Ashio-machi had one measurement facility, the concentration measured by the facility was above the pollution standard; and in the same year, Ashio-machi was only one town which all the concentrations measured by facilities of one town were above the standard (however, it is not specified in the environmental white paper of the year that it was a damage by mining pollution).
足尾町内1局の測定局のうち、1局が不適合で、都市内全測定局の値が不適合となったのは、測定局のある都市の中では、この年度、足尾町のみである（ただし当時の環境白書は、鉱毒被害とは明示していない）。