vietnam dairy
A Vietnamese seller bags dairy boxes at a showroom of the Vietnam Dairy Products Co (Vinamilk) in Hanoi. Reuters

The world’s largest dairy exporter, Fonterra Co-operative Group Limited (NZE:FCG), issued a warning on Saturday to eight of its worldwide importers, after discovering botulism poisoning in a particular type of whey protein concentrate, which is used in the manufacture of a range of products including infant formula, sports drinks and milk powder.

Fonterra said eight of its customers, who imported the tainted whey protein concentrate, which was produced at a single New Zealand manufacturing site in May 2012, are “urgently investigating” the potential presence of Clostridium Botulinum, a bacterium which can cause botulism, in their supply chains.

The revelation, dealing a blow to New Zealand’s dairy industry, has led to global recalls of several hundred tons of dairy products in six countries -- China, Australia, Thailand, Malaysia, Vietnam and Saudi Arabia -- apart from New Zealand, the BBC reported.

The dairy major did not name the eight companies that were affected.

“There have been no reports of any illness linked to consumption of the affected whey protein,” Fonterra said in a statement. “Dairy products such as fresh milk, yoghurt, cheese, spreads and UHT milk products are not affected.”

Botulism poisoning, usually caused by consuming food contaminated with the toxin, affects nerves, resulting in double vision, blurred vision, slurred speech and muscle weakness.

Fonterra Chief Executive Theo Spierings said the company is "acting quickly" to acquire information out about potentially affected product “so that it can be taken off supermarket shelves and, where it has already been purchased, can be returned.”

“We are working closely with New Zealand’s regulatory authority – the Ministry for Primary Industries – to keep New Zealand and offshore regulators informed,” he said.

Fonterra said it identified a potential quality issue in March 2013, when a product tested positive for a harmless strain of Clostridium. Several tests followed the initial discovery, and on July 31, 2013 tests indicated potential presence of a poisonous strain of Clostridium.

“We immediately contacted our customers and the appropriate authorities, so that any potentially affected product could be removed from the marketplace,” Gary Romano, managing director Fonterra’s New Zealand Milk Products, said in the statement.

“We are working with our customers and will provide more information and updates as they become available,” Romano said.

China’s General Administration of Quality Supervision Inspection and Quarantine has asked local dairy importers to recall products manufactured using Fonterra’s tainted whey protein and to step up inspections of dairy products from New Zealand, Bloomberg reported.

In 2008, six infants died and 300,000 fell sick in China after consuming tainted baby formula, prompting authorities to improve measures to ensure food safety.

New Zealand has one the world’s largest dairy industry and exports up to 95 percent of its milk.