Bisphenol A

Bisphenol A (BPA) is a chemical that is mainly used in combination with other chemicals to manufacture plastics and resins. It has been used in the manufacture of these materials for many years. It is used in polycarbonate, a type of transparent, rigid plastic. Polycarbonate is used to make food containers, such as returnable beverage bottles, infant feeding (baby) bottles, tableware (plates and mugs) and storage containers. Residues of BPA are also present in epoxy resins used to make protective coatings and linings for food and beverage cans and vats.

BPA is permitted for use in food contact materials in the European Union, under Commission Directive 2002/72/EC of 6 August 2002 relating to plastic materials and articles intending to come into contact with foodstuffs. It is also permitted for food contact use in other countries such as the USA and Japan.

How can BPA get into our diet?
Small amounts of BPA can migrate from polycarbonate plastics or epoxy resin linings into foods and beverages. BPA can also migrate into foods if the plastic or resin is damaged or breaks down.

Why is there concern about BPA?
BPA is one of a number of chemicals that may have the potential to interact with hormone systems in the body (a so-called 'endocrine disrupter'). It has been known since the 1930s that BPA can mimic the female sex hormone, oestrogen. The effects on fertility and reproduction and the endocrine (hormonal) system have been subject to much scientific debate, linked to reports of low-dose effects of BPA in rodents.

How much can be consumed without harm?
A 3-month-old bottle-fed baby that weighs around 6 kg would need to consume more than 4 times the usual number of bottles of baby formula a day before it would reach the TDI.

What is a Tolerable Daily Intake (TDI)?
The TDI is an estimate of the amount of a substance, expressed on a body weight basis that can be ingested daily over a lifetime without appreciable risk.

Identification in plastics
There are seven classes of plastics used in packaging applications. Type 7 is the catch-all "other" class, and some type 7 plastics, such as polycarbonate (sometimes identified with the letters "PC" near the recycling symbol) and epoxy resins, are made from bisphenol A monomer. When such plastics are exposed to hot liquids, bisphenol A leaches out 55 times faster than it does under normal conditions, at up to 32 ng/hour. Type 3 (PVC) can also contain bisphenol A as antioxidant in plasticizers. Types 1 (PET), 2 (HDPE), 4 (LDPE), 5 (polypropylene), and 6 (polystyrene) do not use bisphenol A during polymerization or package forming, and thus will not leach bisphenol A into food or beverages.

	Some type 7 plastics may leach bisphenol A
	Some type 3 plastics may leach bisphenol A

References
http://www.efsa.europa.eu/EFSA/KeyTopics/efsa_locale-1178620753812_BisphenolA.htm
http://en.wikipedia.org/wiki/Bisphenol_A

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