China has suspended imports of shellfish from the West Coast of the United States after finding  high levels of arsenic and a toxin that causes paralytic shellfish poisoning in recent shipments of geoduck clams from Northwest waters. The indefinite ban affects clams, oysters and all other two-shelled bivalves harvested off the coast of Washington, Oregon, Alaska and Northern California. U.S. officials think the contaminated clams were harvested in Washington or Alaska and are waiting to hear back from Chinese officials for more details to help identify the exact source. Many are concerned about the economic implications of the ban. The U.S. exported $68 million worth of geoduck clams in 2012 – most of which came from Washington’s Puget Sound and almost 90 percent of that went to China. The National Oceanic and Atmospheric Administration is negotiating with the Chinese government about how to reopen shellfish trade, but the ban could last for months. NOAA stopped issuing certification for shellfish exports last Friday.