CFS announces First Hong Kong Total Diet Study findings on mycotoxins

The seventh report of the First Hong Kong Total Diet Study (HKTDS), which has assessed the dietary exposure of the local population to five types of mycotoxins, namely aflatoxins, ochratoxin A, fumonisins, deoxynivalenol and acetyldeoxynivalenols, and zearalenone, was released by the Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department today (December 18).

A spokesman for the CFS said, "The key findings showed that the dietary exposure of the Hong Kong adult population to five types of mycotoxins had been low. Therefore, for the general population, dietary exposure to five types of mycotoxins is unlikely to pose health concern.

Mycotoxins are toxic metabolites produced by moulds. Crops that are under environmental stress or attacked by insects are susceptible to mould infestation and mycotoxins may be produced. For ordinary adults, the diet is the main source of exposure to common mycotoxins.

The World Health Organization (WHO)'s International Agency for Research on Cancer (IARC) classified naturally occurring aflatoxins as carcinogenic to humans, and the Joint Food and Agriculture Organization/WHO Expert Committee on Food Additives (JECFA) advised that intake of aflatoxins should be reduced to as low as reasonably possible although no health-based guidance value has been set.

Aflatoxins can cause liver cancer and the risk for hepatitis B carriers is particularly high, the spokesman noted.

"Naturally occurring aflatoxins are more likely to be found in peanuts, tree nuts, corn, dried figs, cereals and their products. The dietary exposure to aflatoxins of the average and high consumers in the local population was 0.0002 to 0.0028 and 0.0009 to 0.0049 micrograms per kg of body weight per day respectively. The dietary exposure of the local population to aflatoxins was low. Based on the estimated aflatoxin intake and the prevalence of hepatitis B carriers in Hong Kong, aflatoxins contributed approximately eight cases of liver cancer in the Hong Kong population each year, which accounted for less than 1 per cent of liver cancer annually. There is no cause for alarm," the spokesman said.

"For the remaining four types of mycotoxins (ochratoxin A, fumonisins, deoxynivalenol and acetyldeoxynivalenols, and zearalenone), all dietary exposure estimates for them were far below their respective health-based guidance values. The findings suggested that the general adult population was unlikely to experience major undesirable health effects related to the four types of mycotoxins," the spokesman said.

To avoid excessive intake of mycotoxins, the spokesman advised people to maintain a balanced and varied diet to minimise the risk from a small range of food items, and to avoid consuming food that looks mouldy or damaged. As nuts contain many nutrients, such as unsaturated fatty acids, high-quality protein, fibre, vitamins and minerals, people may include unsalted nuts in a well-balanced diet and consume them in moderation. On the other hand, the trade should observe good agricultural and manufacturing practices, source food and ingredients from reliable suppliers and store food properly to minimise mycotoxin contamination of food.

The First Hong Kong Total Diet Study was launched by the CFS in March 2010 and will be completed in 2014. The first six reports that have been released cover the following substances: dioxins and dioxin-like polychlorinated biphenyls (PCBs), inorganic arsenic, polybrominated diphenyl ethers, pesticide residues, metallic contaminants and acrylamide.

The Study aims at estimating the dietary exposure of the general population and various population subgroups to a range of substances, including contaminants and nutrients. The purpose is to assess any associated health risks, focusing on the total diet of the population rather than individual foods.

A total of 150 food items were chosen for the study according to the food consumption pattern of the Hong Kong population. They are being used for testing the level of over 130 substances, including pesticide residues, persistent organic pollutants, metallic contaminants, mycotoxins, macro nutrients and elements. By combining the test results with food consumption data, the dietary exposure of the population to the selected substances may then be estimated.

The full report on the study on mycotoxins is available on CFS' webpage at www.cfs.gov.hk. Study results concerning other substances will be released in phases.

Ends/Wednesday, December 18, 2013
Issued at HKT 14:31