Contaminated cornflour traced
27 July 2004
Contaminated cornflour traced
The New Zealand Food Safety Authority (NZFSA) has investigated lead contamination in cornflour milled from imported corn and is confident that, pending any new information, all of the affected product has been traced.
“About 50 tests have been completed on all potentially affected batches of the Penfords milled cornflour,” said Director of Domestic and Imported Food, Tim Knox.
“Three batches have been found to have unacceptable levels of lead. All of the cornflour has been traced, and the food in which it was used as an ingredient has been assessed to determine the likely levels of lead in the final food product. All of the products that are assessed to have potentially had levels of lead higher than the maximum permitted level for that food type have been recalled. Our assessment is that all other foods are below those levels and pose no safety concerns. For foods that have already been consumed, our assessments, and expert medical opinion, indicate that there is no health risk. This is because cornflour is generally used as an ingredient and the level of lead in the overall food would be below maximum permitted level, and well below the acceptable daily intake.”
In addition, Dr Donald Campbell, Medical Officer of Health in Palmerston North, says that lead is cumulative but short exposures to relatively low levels are not significant.
“Although lead may slowly build in the body during periods of exposure, levels drop again once that exposure ceases. This is the case here. The levels are lower than those of real concern in the environment, such as from lead paint and hobbies that involve lead, such as shot and solder.”
Tim Knox says NZFSA’s assessment indicates that a 70kg person would have to consume one 400gm packet of the most-affected batch of cornflour each week for some time before lead levels would rise enough to cause a health risk.
“That’s not only unlikely because of the amount one would need to consume, but also because the contaminated cornflour was only in the food distribution chain for a short time. However, we understand how worried some people might be, and suggest that they consult their doctor if they have concerns.”
Although NZFSA has traced all of the cornflour affected, investigations are continuing to double-check the information received as well as to trace the source of the contamination.
“It is possible that the imported corn was contaminated somewhere in transit between China and the mill. We are working with all concerned to try and isolate the most probable causes of the problem. Although the corn was imported 10 months ago and we are unlikely ever to know the exact cause, we will be identifying weaknesses and working with the relevant local and international authorities to address issues.”
The three affected batches were milled from a portion of a one-off 6000 tonne shipment of corn from China, imported in September 2003. The affected batches, about 45 tonnes each, were milled between October 2 and 4.
The contamination was found during testing by NZFSA as part of its Total Diet Survey. The manufacturer of the affected product, 100gm Robinsons Step Up Egg Custard, was immediately informed, and issued a recall notice for all batches, even though not all would have used the affected cornflour as an ingredient.
Other products to have been recalled are Pam’s Maize Cornflour 400 gm packets (Lot 3163, Best Before DEC 05; and Lot 3153, Best Before DEC 05) [South Island only]; Gilmours Maize Cornflour 5kg (Lot 3193) [South Island only]; and Edmonds Fielder’s Cornflour 300g with Best Before Dates 30.09.05 and 01.10.05.
Of the 105.78 tonnes of cornflour, 22.1 were exported to Australia (authorities there have been alerted and supplied with all information). Another 25.1 tonnes was exported to Fiji and NZFSA is working with authorities there as well as the two importers to assist in tracing where and how the product was used. 0.45 tonnes was used in the Robinsons egg custard, 4 tonnes in the recalled Pam’s and Gilmours products, and about 32 tonnes in the various Edmonds product. About 22 tonnes has been used as a minor ingredient in foods, diluting it to such an extent that the levels are below the maximum permitted level of lead for those food types. Other batches of cornflour were milled from the contaminated corn, but were also used in industrial and non-food products.
“While high levels of lead in food are unacceptable, it is important to remember that not all the cornflour in each batch may have been affected. In addition, the bulk of the product was used as an ingredient and, as such, makes up a small proportion of the food in which it has been used. Our assessment shows that, in all but the recalled products, lead levels are likely to be within the acceptable limits for the foods concerned,” says Tim Knox.
NZFSA Programme Manager (Toxicology and Residues), John Reeve, says confusion of regulatory levels and human health needs to be addressed so people can judge for themselves the real risk.
"This issue has highlighted once again the fact that regulatory limits for contaminants in foods are not set on the basis of health risk, but on the basis of ensuring the best practices in the production of foods. The fact is that the recalled products have unacceptably high levels of lead in them and are therefore subject to recall. However, it is not correct to claim that they pose an immediate health risk. The measure of this is whether the dietary intake exceeds the level identified by the World Health Organisation as being acceptable, and not simply whether the product contains contaminants at levels exceeding regulatory limits."
Tim Knox says that a low level of lead is not unexpected as lead is present in the environment, from both natural and man-made sources. However, the levels detected during targeted monitoring for the Total Diet Survey were unacceptable.
“Looking at heavy metal contaminant levels in foods, and in particular baby foods, is a key element of the Total Diet Survey. Based on trends from previous surveys we do not expect to find high levels of lead contamination, as lead levels in New Zealand food have dropped to one of the lowest in the world, with levels in food now about five percent of 1982 levels.
“We run a comprehensive science programme to confirm the safety of New Zealand food. These systems have been shown to be effective in uncovering issues as is evidenced in this situation.
“Our monitoring uncovered the problem, it was confirmed as an issue of concern, and the manufacturers and distributors concerned immediately did everything right.”
Tim Knox notes that NZFSA will soon be releasing its imported foods discussion document.
“The aim of the review is to identify the needs and expectations of New Zealanders, identify major food safety and security threats and make recommendations on cost-effective ways that the existing import controls could be improved.
"International trade in food and food-related products continues to grow at a rapid rate. Foods imports into New Zealand have increased significantly since 1996. This has led to an emergence of new risks and concerns over the safety and security of the food supply. A number of countries have reviewed and strengthened the measures they have in place to ensure food imports are safe and secure and it is timely for New Zealand to do the same." he says.