The protesters, among them a Catholic priest, say the containers hold toxic and hazardous waste, although a recent study by Philippines officials suggests they're simply stuffed with household trash.
"Prime Minister Stephen Harper's government is an embarrassment to the civic-minded and environmentally conscious Canadians," priest Robert Reyes said at a protest last week on the steps of the Canadian embassy.
"We know this is not the real Canada. We urge Prime Minister Harper to take immediate action. Take back your illegal waste shipment now."
But a spokeswoman for Foreign Affairs reiterated the government's long-stated opinion that the case is a "private commercial matter involving a Canadian company and its Philippines partner."
"The embassy engaged the government of the Philippines and its appropriate agencies to actively seek to assist and resolve it in keeping with the spirit of collaboration and co-operation that characterizes our countries' relations," Amy Mills said in an email.
Chronic Inc., a plastics exporter based in Whitby, Ont., shipped the containers — supposedly filled with recyclable Vancouver plastics — to the Philippines in the spring and summer of 2013.
But upon inspection, the country's Bureau of Customs found the containers were filled with stinking household garbage, including used adult diapers and kitchen waste.
The bureau said the material could "pose biohazard risks" and impounded the shipment.
Chronic Inc.'s owner, Jim Makris, couldn't be reached for comment. But he denied in an interview with the Toronto Star a year ago that he shipped garbage to the Philippines and also suggested he was being punished for failing to pay off Filipino officials when his containers arrived.
Late last year, the Philippines Department of Justice recommended filing criminal charges against Makris's Philippines partner, Chronic Plastics, for misrepresenting the contents of the containers.
In her email, Mills said that Canada was "pleased that this matter has been resolved" following the report from the Philippines' Department of Environment and Natural Resources that deemed the contents of the containers non-hazardous.
Environmentalists and some Philippines officials appeared to take issue with the notion that the case is resolved.
Late last year, the Environment Department recommended the garbage be returned to Canada under the provisions of the Basel Convention. That treaty, signed by both Canada and the Philippines, prohibits developed countries from shipping garbage to developing nations.
"The Basel Convention says, as a developed country, (Canada) cannot export waste," Filipino environment secretary Ramon Paje said in a televised interview. "That would be considered as dumping."
Angelica Carballo-Pago of BAN Toxics said even if the garbage is not hazardous, its shipment to the Philippines still violates the convention and Canada must take the containers back.
"The wastes, after all, have been found to be heterogenous — as opposed to the exporter's declaration that they are homogenous, recyclable materials — and are mostly household wastes," she said from Manila.
International Trade Minister Ed Fast was in Manila on Friday, meeting his Philippines counterpart. The garbage containers weren't discussed, an official in Fast's office said.
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