* EU's trade commission says China must tread carefully
* Investigation is latest to strain trade ties
By Sebastian Moffett
BRUSSELS, Feb 16 (Reuters) - The EU launched new investigations into suspected Chinese product-dumping on Thursday, raising the possibility of more import tariffs on Beijing as Europe's top trade official warned China risked turning Europeans against free trade.
EU Trade Commissioner Karel De Gucht said during a visit to Hong Kong that China needed to be sensitive to perceptions that its huge economy is a threat in Europe.
"China must grasp that European support for open markets can only be guaranteed if accepted by the public at large," De Gucht said in a speech, as the EU opened anti-dumping investigations into ceramics and pipe fittings made in China.
"That acceptance requires a perception of fairness."
Trade between the EU and China has boomed in recent years, reaching almost 400 billion euros ($523 billion) in 2010, the latest annual data available. However, Europeans are unhappy with China's system of subsidies designed to nurture industry.
EU complaints against Chinese dumping range from shoes to steel fasteners. De Gucht has in the past complained that China subsidises "nearly everything", making it hard to compete.
The EU's new investigations will examine whether the ceramic products and pipe fittings are being dumped and are harming EU industry, said the European Commission, the EU's executive.
The EU has nine months to decide whether to impose provisional duties, and must conclude its investigation within 15 months. If it decides products have been dumped it can impose tariffs, which analysts say could be up to 50 percent of product value.
The investigation into Chinese ceramic plates and cups followed a complaint filed last month by EU producers.
Imports of ceramic kitchenware from China at "clear predatory prices" have significantly increased over the last years, reaching a share of the EU market above 60 percent," the European Federation for Table- and Ornamentalware said in a statement.
In the first half of 2011, the average Chinese price of 1.45 euros was 80 percent lower than the average price of EU imports from other countries, the group said.
That is costing jobs in the EU, where the sector employs 25,000 people, a figure that has declined by 10,000 since 2007 but is still a sizeable industry in Germany, France and Italy.
"Unfair competition of dumped imports clearly undermines the long-term viability of EU companies," the federation said.
Not all Europeans are against China, however, and argue the EU should accept low-cost imports from China and instead focus on higher-value products with better profit margins.
"Merely slapping unnecessary duties on products from outside the EU will not make the industry in Europe more competitive," said one industry group, the Importers of Ceramic Tiles in Europe.
"It will only create more cost to wholesalers, retailers, shipping companies, intermediary producers and in the end European consumers." (Editing by Robin Emmott)