Technical trade barriers affected 34.6 percent of Chinese exporters in 2007, up 3.2 percentage points from the previous year, a top industry regulator said in Beijing on Tuesday.

Direct losses from such barriers totaled $49.5 billion, up $13.5 billion from 2006, according to a report by the General Administration of Quality Supervision, Inspection and Quarantine.

The report was based on a sample survey of 2,198 exporters in 31 provinces and municipalities.

Almost 37 percent of the losses were connected to the United States, followed by the European Union at 34.5 percent, Japan at 10.4 percent, the Association of Southeast Asian Nations at 4.4 percent and Russia at 3.6 percent.

"Among the barriers, certificate requirements, technical standards, safety requirements, environmental standards, poisonous material limits and packaging" had the most impact, the administration said.

About 39 percent of the losses were connected with mechanical and electrical equipment, followed by 17 percent for rubber and leather, 17 percent for agricultural produce and food and about 10 percent for textiles, hats and footwear.