"It can be said that the quality of China's exports all are guaranteed," Wang told reporters at a regularly scheduled briefing.

However, the U.S. Food and Drug Administration advised consumers to "avoid using tubes of toothpaste labeled as made in China," according to a statement posted on the agency's Web site.

"Out of an abundance of caution, FDA suggests that consumers throw away toothpaste labeled as made in China," the statement said.

Chinese-made toothpaste has been banned by numerous countries in Asia and the Americas for containing diethylene glycol, or DEG, a chemical often found in antifreeze. It is also a low-cost -- and sometimes deadly -- substitute for glycerin, a sweetener in many drugs.

The New York Times reported Thursday that tainted Chinese toothpaste had been more widely distributed in the United States than had been previously reported. It said about 900,000 tubes have turned up in places including correctional facilities and some hospitals, not just at discount stores.

A spokesman for North Carolina's Department of Correction said this month that Pacific brand toothpaste was distributed to prisoners who could not afford to buy a name brand at prison stores. The tubes were taken away after trace amounts of DEG was found in them.

Officials in Georgia and North Carolina told the Times there had been no illnesses reported, and that the toothpaste in question was being replaced with brands not manufactured in China.

Chinese exports came under scrutiny earlier this year with the deaths of dog and cats in North America blamed on Chinese wheat gluten tainted with the chemical melamine.

Since then, U.S. authorities have turned away or recalled toxic fish, juice containing unsafe color additives and popular toy trains decorated with lead paint.

On Wednesday, three Japanese importers recalled millions of Chinese-made travel toothpaste sets, many sold to inns and hotels, after they were found to contain as much as 6.2 percent of diethylene glycol.

Wang, the Commerce Ministry spokesman, said Chinese experts have already "explained the situation."

He gave no details, although the country's quality watchdog has in past cited tests from 2000 that it said showed toothpaste containing less than 15.6 percent diethylene glycol was harmless to humans.

Also Wednesday, Beijing police raided a village where live pigs were force-fed wastewater to boost their weight before slaughter, state media reported.

Plastic pipes had been forced down the pigs' throats and villagers had pumped each 220-pound pig with 44 pounds of wastewater, the Beijing Morning Post reported Thursday.

Paperwork showed the pigs were headed for one of Beijing's main slaughterhouses and stamps on their ears indicated that they already had been through quarantine and inspection, the paper said. Suspects escaped during the raid and no arrests were made, it said.

The case underscored China's chaotic food safety situation, where manufacturers and distributors often use unapproved additives, falsify expiration dates or find other methods of cutting corners to eke out small profits.

Officials have in recent weeks underscored the need to tighten up inspections, punish violators and increase surveillance.

Wei Chuanzhong, deputy director of the General Administration of Quality Supervision, Inspection and Quarantine, said local governments "should be fully aware of the importance and improve responsibility for imported and exported food safety."

His remarks, made during an inspection tour of the port city of Tianjin, were posted Thursday on the administration's Web site.

Earlier this week, inspectors announced they had closed 180 food factories nationwide in the first half of this year and seized tons of candy, pickles, crackers and seafood tainted with formaldehyde, illegal dyes and industrial wax.

"These are not isolated cases," Han Yi, an official with Wei's quality administration, was quoted as saying in Wednesday's state-run China Daily newspaper.

Han's admission was significant because the agency has said in the past that safety violations were the work of a few rogue operators -- a claim aimed at protecting China's billions of dollars of food exports.