Poison cloud over cassava

By PHILIP ENGLISH

The safety of cassava is under review, out of concern that the popular tropical Pacific Island root crop may contain hydrogen cyanide, which can cause respiratory and heart problems.

The plant is a cheap source of carbohydrates for people living in the humid tropics, particularly in Brazil, Thailand, Nigeria and Indonesia.

Cassava, also known as manioc, is imported into New Zealand from Fiji and Tonga, but in a form that reduces the risks associated with eating it.

Food Standards Australia New Zealand is calling for public comment on the handling of cassava to protect consumers.

Peeling and washing the vegetable reduces the risk of exposure to hydrogen cyanide, which can be present through naturally occurring cyanogenetic glycosides.

Cooking or fermenting further reduces the risk.

Cassava is imported into New Zealand peeled and frozen in bags and is relatively widely available in Pacific Island food shops. It is also sold as chips.

There are no mandatory warning statements or advice to consumers to alert them to the potential risks of using raw or improperly prepared cassava.

Kathy Pritchard, a public health official of the Auckland District Health Board, said she had not heard of any health problems in New Zealand caused by people eating this food.

Malakai 'Ofanoa, of the Department of Maori and Pacific Health at the University of Auckland Medical School, said there were reports of people falling ill and blaming cassava in the dry season in the Pacific Islands.

But there was no scientific evidence to back up the claimed link.

Anyone who ate cassava could tell its condition by its taste.

Food Standards Australia New Zealand is also calling for public comment on a new food-processing aid from a GM source.

Glucose oxidase, used in the baking industry to strengthen gluten in dough, is an enzyme produced through the use of a genetically modified host fungus.

The applicant said the enzyme was safe to use in food processing and that "approval of glucose oxidase from this source would promote international trade and reduce technical barriers to trade".

The food standards authority said it had concluded that the use of glucose oxidase was technically justified and posed no significant risk to public health and safety.

The deadline for submissions on glucose oxidase is September 18 and for cassava, October 2.

Food Standards

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