Two Japanese companies said Friday they have started recalling all undelivered cloth masks they supplied under Prime Minister Shinzo Abe's mask distribution program to address the novel coronavirus pandemic, following numerous complaints of tainted products earlier this month.

Trading house Itochu Corp., and pharmaceutical and medical equipment maker Kowa Co. said they had also found similar problems with masks still in their inventories.

"We will ask the firms that have supplied masks to continue thorough checks for hygiene purposes," health minister Katsunobu Kato said at a press conference Friday.

Itochu and Kowa are among three companies that have been tapped to provide face masks to pregnant women and general households under Abe's initiative, which aims to give each household two cloth masks amid shortages due to the coronavirus pandemic.

The masks provided by the three companies are being manufactured at factories in China, Vietnam and Myanmar.

The two companies said they will strengthen quality-control measures to prevent a similar problem from recurring.

Itochu explained in a statement released Thursday that the government, after failing to secure the necessary quantity of masks from domestic manufacturers, had expanded its call for help to companies other than mask producers.

"We also received a strong request as part of these efforts. We decided to respond because it is a state emergency and doing so will help prevent the spread of the new coronavirus," the company said.

The Nagoya-based Kowa said in a separate press release, "We have facilitated the emergency production of cloth masks through cooperative overseas factories, mainly in China, at the request of the government."

Japanese apparel maker Matsuoka Corp., which is providing masks made at its factories in China and Myanmar, said it had not received any complaints from the government about defects.

"We will continue to deliver masks as planned," a company spokesperson said.

Under the initiative, Kowa made a contract for supplying masks worth 5.48 billion yen ($51 million) and Itochu got a 2.85 billion yen contract, while Matsuoka's contract is valued at 760 million yen, according to the Ministry of Health, Labor and Welfare, though the ministry declined to clarify how many masks each company will provide.

On April 14, ahead of deliveries to general households, the health ministry started distributing around 500,000 cloth masks to pregnant women through municipal offices and by shipping them to medical and nursing facilities.

But the ministry was soon flooded with complaints about tainted masks, including those with human hairs.

Kato said Tuesday that the ministry confirmed 7,870 defective masks had been delivered to 143 municipalities. The ministry also suspended deliveries the same day.

Deliveries of cloth masks to ordinary households started on April 17 in Tokyo, with the government aiming for distribution to the around 50 million households across the country by the end of May.

Meanwhile, the health ministry has also received complaints about the quality of cloth masks already delivered to households, a government official said, adding that the ministry will conduct inspections and provide replacements as necessary.

The mask distribution initiative has drawn derision on social media, earning the nickname "Abenomask," a pun on Abe's "Abenomics" economic policy mix.

The policy has also been met with skepticism in foreign media due to its hefty cost of 46.6 billion yen despite the relative ineffectiveness of cloth masks in preventing coronavirus infection.

The program is part of the government's emergency economic package worth over 100 trillion yen, designed to support the economy through the coronavirus outbreak.

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