China's quality watchdog said on Tuesday that a sample survey shows 80.9 percent of products made in China for domestic consumption were up to quality and safety standards in the first half of 2007.

The survey covered 7,200 different products from 6,362 enterprises, with an emphasis on food, everyday commodities and farming machinery and fertilizers, the General Administration of Quality Supervision, Inspection and Quarantine (GAQSIQ) said at a news conference on Tuesday.

The administration found that 93.1 percent of products made by large enterprises are up to standards -- the figure was 84.2 percent for medium-sized enterprises and 72.9 percent for small enterprises.

The survey revealed that 19.1 percent of products made in China for domestic consumption are substandard in the first half of 2007,moving down from 21.6 percent from a year ago.

Tinned and preserved fruit and dried fish registered the lowest quality scores with key problems being excessive amounts of microorganisms or additives, the administration said.

The quality watchdog cracked 23,000 cases of fake and low-quality food from December 2006 to May 2007 and a total of 180food manufacturers were shut down for making substandard food or using inedible materials for food production.

Meanwhile, "99 percent of food exported to the United States was up to safety standards over the past two years, which is a very high percentage," said Li Yuanping, a senior official in charge of imported and exported food safety in the GAQSIQ, in June.