OYLMPIA, Wash. -

State health officials are in the process of testing shellfish samples following toxicity concerns that prompted China to ban West Coast shellfish.

KOMO-TV reports that Washington state Department of Health technicians are now testing 36 shellfish samples from the Poverty Bay area near Federal Way.

Officials have already shut down commercial guoduck clam harvesting on 135 acres of state-owned aquatic land. Earlier this month, the state learned that Chinese authorities detected arsenic in a shipment from Washington. The state Health Department had traced that shipment back to clams harvested in October by the Puyallup Tribe in Poverty Bay.

The China import ban is creating a hardship for the state's shellfish industry, since that country is a major market for Washington harvesters.