China's top quality authority said on Monday it has demanded its counterparts in New Zealand provide detailed information and a report on risk evaluation on its dairy products reported to have traces of a toxic substance.

"We contacted concerned departments in New Zealand multiple times after its Ministry for Primary Industries announced on Jan 24 it had ordered to suspend the use of fertilizers containing dicyandiamide on the country's pastures," Fu Wenbiao, deputy director of the General Office of the General Administration of Quality Supervision, Inspection and Quarantine, said at a news conference. "We will continue to pay attention to, and investigate, the issue."

Low levels of dicyandiamide, or DCD, a low toxicity chemical, were found in dairy products produced in New Zealand, according to media reports.

DCD got into the milk as farmers in the country applied the chemical to pastures to prevent nitrate, a fertilizer byproduct that is also harmful to health, from getting into rivers and lakes.

Some experts have raised concerns, as about 80 percent of China's milk imports come from New Zealand.

New Zealand's Ministry for Primary Industries has issued reassurances that the dairy products are safe, saying only a very small amount of the products might contain the residue.

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