Health minister Chikara Sakaguchi said Friday that imports of Iranian pistachio nuts may be outlawed because they contain a carcinogenic toxin.

"There's a possibility that the nuts could be subject to an import ban," Sakaguchi told reporters.

In the wake of revelations that imported Chinese spinach contained high levels of pesticide residue, lawmakers are currently hammering out legislation that would make banning imports of foods suspected of posing health hazards much easier.

The Health, Labor and Welfare Ministry has detected the presence of aflatoxin, a toxin produced by certain kinds of mildew, in Iranian pistachio nuts on 71 occasions since 1999.

The substance is thought to cause liver cirrhosis and cancer, while its presence in foodstuffs is prohibited under the Food Sanitation Law.

According to statistics compiled by the ministry, aflatoxin was detected during pistachio import inspections on 27 occasions in 1999, on 19 occasions in 2000, on 23 occasions in 2001 and twice in the first six months of 2002.

In 1997, the level of aflatoxin detected in one batch of Iranian pistachio nuts was equivalent to 242 times the minimum level detectable via inspections.

All Iranian pistachio nuts are subject to inspections upon their arrival in Japan, and each nut that was found to contain the toxin was disposed of, according to health officials.

Jungoro Kondo, the health ministry's top bureaucrat, raised the issue with Iranian Ambassador to Japan Ali Majedi during a meeting Thursday.

Japan imported about 3,700 tons of pistachio nuts in 2001, of which 1,200 tons, or about 32 percent, came from Iran, according to ministry statistics.