Late last week, one of Japan's major food processors announced that it would be recalling over 6 million frozen food items due to a contamination scare.

Maruha Nichiro Holdings Inc. warned that a problem at one of its facilities in Gunma Prefecture meant that the products – a diverse range of over 80 foods produced at the plant – could be contaminated with malathion, an organophosphate pesticide used in agriculture and domestic products.

The company is recalling products produced at the Aqli Foods plant which had been supplied to shops and restaurants. A spokesperson said the firm been alerted to the problem in November, when it received the first of a series of calls warning that a frozen pizza produced at the plant had smelled of petrol or oil.

Subsequent testing revealed that nearly half of the samples returned tested positive for the insecticide. Malathion has a relatively low toxicity, but can sill cause harmful effects if consumed by humans. Maruha Nichiro was forced to apologise on 31st December for underestimating the seriousness of the contamination, admitting that a company spokesperson had gravely understated the potential of malathion to cause harm.

The spokesperson's claim that a small child would have to eat 60 contaminated corn croquettes before suffering nausea or stomach cramps was seized upon by officials from the ministry of health, who pointed out that just one eighth of a contaminated croquette would produce these effects.

The company said in a press release earlier this week that it had been unable to identify the cause of the contamination. Maruha Nichiro Holdings announced on Friday (3rd January) that it had formed a task force to investigate the incident and that, as malathion had not been detected at the production plant, it would investigate the potential for contamination earlier in the production process, further down the supply chain.

So far, there have been no reports of illness associated with the contamination.