Not much progress has been made towards finding those responsible for the appearance of poisonous gyoza on Japanese store shelves, but Japanese police have announced that their investigation of recalled gyoza supports their claim that toxic chemicals entered the frozen gyoza somewhere in China:

The first case in which the pesticide was detected in a sealed dumpling package involved a product recalled from a supermarket in Hirakata, Osaka Prefecture, in February.

The latest case involves a product dated Oct. 1, 2007, made by the Chinese company Tianyang Food — one of 39 recalled products returned by shops and stored at a company in Osaka.

It is unclear which shop returned the product, police said.

The scientific investigation laboratory of the Osaka police, at the request of the Hyogo Prefectural Police, examined the 39 packages of dumplings and confirmed they were perfectly sealed using a water infiltration technique.

Methamidophos was detected on the surface of all 39 packages, as well as inside one of the sealed packages, according to the test results.

Among the 38 other packages, methamidophos was detected in nine dumplings in a package with a 1-mm hole and inside another package that also had a 1-mm hole.

Meanwhile, the Tokyo Metropolitan Government is planning to introduce new packaging rules aimed at making cooked frozen food producers in Japan show countries of origin for main ingredients of products:

According to Tokyo’s plan, domestic producers of cooked frozen foods will be obligated to disclose the countries of origin of the three top ingredients, which each account for 5 percent or more of the total weight of the product.

If some ingredients are from more than one country, all names must be shown.

Wheat and other processed ingredients will be excluded, however, because their countries of origin will have to be traced further back, according to the officials.

In the case of frozen gyoza dumplings, the labeling for the main ingredients would, for example, be: “cabbage (domestic, China); wheat; pork (Canada); leek.”

If the product name features “green perilla” as in “green perilla gyoza,” then the country of origin for the featured ingredient must also be shown regardless of the ratio of its weight.

However, the rule is not as strict as one might expect. Companies that refer customers to a URL or phone number instead of printing the data on their packages will be considered in compliance with the new rule. There will also be no penalty against companies that violate the new ordinance.