"Nothing is available to be seen at the facilities. They were closed down, machinery dismantled," said Batts.

Chinese officials did obtain samples at the facilities in April and sent them to an independent laboratory for testing, he said. "We assume we will have access to those when the results are ready."

FDA said it received "extensive cooperation" from China's General Administration of Quality Supervision, Inspection and Quarantine but also noted the agency had "limited authority" over the processors. Officials said they were satisfied the agency shared its information with FDA.

The FDA investigators are scheduled to return to the United States next week.

Separately, two senior Democrats in Congress asked U.S. Trade Representative Susan Schwab in a letter whether the United States can challenge the food rules of other nations "based on evidence they are not meeting international standards and may be endangering public health in the United States.

"China is especially poor at meeting international food safety standards," wrote Connecticut Rep. Rosa DeLauro and Assistant Majority Leader Richard Durbin of Illinois.

China shipped $2.3 billion in agricultural products to the United States in 2006.

Skretting Co., based in Vancouver, Canada, announced a recall of fish feed that may contain the industrial chemical. The feed was shipped to at least seven fish hatcheries in the U.S. Northwest. A sample taken from a hatchery in Oregon tested positive for melamine.

Two commercial fish farms will be checked to see if they got fish feed containing melamine, said FDA. The agency was tracing how much of the feed was distributed and how widely.

"Humans who may have eaten fish containing the melamine-contaminated fish feed have a very low health risk," said Dr. David Acheson, assistant FDA commissioner for food protection.

Another FDA official, Stephen Sundlof, said melamine is "very water soluble" and is flushed from animals quickly. As a result, it was unlikely to accumulate in muscle meat, he said.

Scientists are conducting an exposure assessment as part of deciding what to do with hogs and chickens that are being held on a number of farms.

The FDA has restricted imports of all vegetable proteins from China and is not releasing the material until shippers provide documentation of tests showing the protein to be free of melamine, Acheson said.

The agency also is testing all imports of pet food from China for melamine contamination, and plans to begin sampling imports of fish feed from China soon, he said.

In the United States, the FDA is visiting manufacturers and processors who use vegetable protein concentrates to sample for melamine contamination. It also is doing some targeted sampling of domestically made human food, he said.

The FDA also confirmed that a second U.S. company, which it said was based in Illinois, was found to be distributing the same contaminated material as ChemNutra.

Copyright © 2007 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.

China's Yellow River 10 pct sewage - group

Last Updated: 2007-05-11 10:46:42 -0400 (Reuters Health)

BEIJING (Reuters Life!) - Untreated sewage from factory discharges and urban centres now accounts for 10 percent of the Yellow River's flow, a prominent Chinese non-governmental group said.

The volume of waste water flowing into the river, China's second longest, doubled from 2 billion tonnes to 4.3 billion between 1980 and 2005, Ma Jun, director of the Institute of Public and Environmental Affairs, a Beijing-based NGO, told the China Daily.

"It now accounts for about one-tenth of its total volume," Ma said.

The 5,464-km (3,395-mile) river supplies water to more than 150 million people and irrigates 15 percent of the country's farmland, but has lost a third of its fish species and is 70 percent unfit for drinking or swimming, state media have reported.

Fearing environmental degradation could slow China's booming economy, Chinese Premier Wen Jiabao has made sustainable development a key tenet of central government policy.

But growth in heavy industry continues apace along the river's middle reaches.

About 400 billion yuan ($52 billion) worth of coal and chemical-based projects were earmarked for construction along an 800-km (500 miles) stretch of the river between China's arid northern regions of Ningxia and Inner Mongolia, the paper said, citing Xinhua news agency.

Twenty million tonnes of industrial sewage were discharged into the river every year at Baiyin, a metallurgical industrial base in China's northwestern Gansu province, the paper said, quoting an investigative report by state-run China Central Television.

"Many of our children have no hair and bad teeth," the paper quoted Wang Mingzhi, a Baiyin resident, as saying.

"Heavy metals in the water are very harmful to people's health," Wang said.

Polluters had little incentive to curb effluents, Ma said.

"For companies that pollute, it is cheaper to break the law and pay the fine than it is to abide by the rules."

($1=7.686 Yuan)

Copyright © 2007 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.