Mitsui Chemicals Inc. exported an agricultural chemical containing a toxic dioxin to the United States and Turkey for more than two years after it stopped domestic sales in March 1997, government officials said.
The chemical, pentachloronitrobenzene (PCNB), is used to destroy club root, a disease that attacks cabbages by causing their roots to swell.
Mitsui Chemicals re-examined the properties of PCNB in 1997, when the toxic nature of a range of dioxins came under scrutiny in Japan.