Slight amounts of radioactive iodine have been detected in tap water in Tokyo, its vicinity and most prefectures neighboring Fukushima apparently due to the nuclear crisis at the Fukushima Daiichi nuclear power plant, the government said Saturday.

While the substance was found in Tochigi, Gunma, Niigata, Chiba and Saitama prefectures as well as Tokyo, traces of cesium have also been found in tap water in two of them -- Tochigi and Gunma, the Ministry of Education, Culture, Sports, Science and Technology said, adding their levels do not affect human health even if they are taken in.

Among them, Tochigi, Gunma and Niigata border Fukushima Prefecture.

In Maebashi, Gunma, 2.5 becquerels of iodine and 0.38 becquerel of cesium were detected Friday per kilogram of water, the prefectural government said, adding it is the first time the substances were found since it began testing tap water for radioactive materials in 1990.

The Nuclear Safety Commission of Japan limits an intake of iodine at 300 becquerels per kilogram of water and of cesium at 200 becquerels.

Source: ANTARA