Something fishy about latest NZFSA diet survey

18 August 2009

Something fishy about latest NZFSA diet survey

Swimming with sharks could be safer than eating some varieties of fish sold in New Zealand, Green Party Food Safety Spokesperson Sue Kedgley said today.

The latest New Zealand Food Safety Authority diet survey showed battered fish tested in Dunedin had a mercury level ten times that of battered fish in Napier. Battered fish tested in Auckland was also much higher in mercury than in other regions.

“NZers deserve answers as to why battered fish samples tested in Auckland and Dunedin were significantly higher in mercury than in other areas and why fresh fish from Dunedin was found to have twice the level of arsenic than fish on sale in Auckland,” said Ms Kedgley.

Most fish are low in mercury however longer lived predatory fish tend to build up their mercury levels. These fish include shark or flake, swordfish, marlin and broadbill. Shark is a common ingredient in fish and chips. Research published last year in the Medical Journal of Australia suggests even relatively low levels of mercury can affect children's brain development

Ms Kedgley noted that a recent MAF Biosecurity decision allowed the importation of Vietnamese catfish farmed in the Mekong River to be imported in significant quantities to New Zealand, despite concerns being raised about water pollution in the Mekong River.

“Because we don’t have mandatory Country of Origin Labelling, no-one will know if some of these Vietnamese catfish are turning up in the latest diet survey and explaining the high levels of mercury in some fish,” said Ms Kedgley.

Battered fish in Dunedin and Auckland also had higher levels of methyl mercury.

“Methyl mercury can cause irreversible damage to the central nervous system, and can cross the blood-brain barrier and the placenta and accumulate in the body,” said Ms Kedgley.

Fresh fish from Dunedin contained more than twice the level of arsenic found in fish on sale in Auckland.

“The levels were so high in Dunedin that even one fish meal a week is likely to push the intake beyond the World Health Organisation’s ‘Tolerable Weekly Intake’ - especially for women,” Ms Kedgley said.

Ms Kedgley was also concerned at the high levels of cadmium and arsenic found in oysters and some varieties of fish.

Arsenic and Cadmium are cumulative and toxic elements, and high levels of cadmium and arsenic can have serious effects on health.

“This is especially concerning given that ERMA has warned that 10% of water in New Zealand has high levels of arsenic,’” said Ms Kedgley.

Link to the 2009 NZFSA diet survey

http://www.nzfsa.govt.nz/science/research-projects/total-diet-survey/2009-q1-nztds-analytical-results-rpt-final-aug-09.pdf

Link to the Medical Journal of Australia and a study regarding mercury and children’s development

http://www.mja.com.au/public/issues/188_01_070108/letters_070108_fm-1.html

ENDS