Posted 15/11/2010 by Roger Beckmann
Food Standards Australia New Zealand (FSANZ) has released its
report on Bisphenol A (BPA) in food packaging and the risks to consumers. The compound BPA has a controversial history. It is suspected of being an endocrine disruptor (a chemical that mimics some of the natural hormones of the human body). It can also be directly toxic at high enough doses. More recent studies have found a range of other possible adverse effects from BPA, but this research is still preliminary and subject to confirmation.
Some materials containing BPA have been banned in some countries (i.e. Canada), and there have been
suggestions that Australia should follow suit. On 30 June 2010, the Australian Government announced the voluntary phase out by major Australian retailers of polycarbonate plastic baby bottles containing BPA.
BPA is a synthetic organic compound used in some food packagings, and particularly within the lining of cans where it stops the food coming into contact with the metal. It can also be found in polycarbonate (hard) plastics, such as baby bottles. BPA can migrate from these materials into foodstuffs, but the toxicity of any substance depends on the dose. So two questions must be answered:
- What is a safe quantity of BPA that can be ingested by people of different ages with no ill effects, if indeed there is a safe quantity?
- What is the concentration of BPA actually present in foodstuffs, and therefore how much BPA would Australians typically consume?
The first question has been examined by the World Health Organisation (WHO) and the US Food and Drug Administration which concluded that a tolerable daily intake (sometimes called a maximum safe exposure) of BPA would be 0.05 milligrams per kilogram of body weight per day. WHO has recently finished another examination of BPA and
concluded that the substance does not accumulate in humans, and is rapidly eliminated in the urine.
To answer the second question – about how much is present in the Australian diet – FSANZ has tested various foods, including infant foods. The consumer association Choice had previously done its own
survey and analysis.
FSANZ found BPA at very low concentrations in some foodstuffs. There was considerable variation in the quantities between different foodstuffs, and in different items of the same foodstuff. However, FSANZ concluded that 'levels of intake of BPA are very low and do not pose a significant human health risk for any age group.' To illustrate this point, it has calculated that, just to reach the maximum safe level, 'a 9-month old baby weighing 9 kg would have to eat more than 1 kg of canned baby custard containing BPA every day, assuming that the custard contained the highest level of BPA found [in the survey].'
The European Food Safety Authority has also recently issued a
statement, in which it concludes that BPA maximum exposure of 0.05 milligrams per kilogram of body weight remains safe – i.e. that exposures to concentrations lower than this need not be of concern. Not everyone agrees. Denmark has introduced a temporary
ban on BPA from 1 July 2010 for materials that are in contact with foodstuffs designed for infants up to the age of 3 years. However, this was on the basis of an assessment conducted by the National Food Institute at the Technical University of Denmark, which studied the exposure of laboratory rats to BPA
– so these results may not be applicable to humans.
The FSANZ report makes the following comment:
FSANZ acknowledges that there are some unresolved uncertainties in the data on BPA, and notes that further studies are currently being conducted in the US to address these uncertainties.
FSANZ has said it will assess these new studies when they become available. Full details of the new FSANZ analysis can be found
here.
(Image sourced from: http://www.abc.net.au/reslib/201009/r632111_4314846.jpg)