Is it OK to drink your coffee from a polystyrene cup? There are scary stories on the internet about the so called dangers of this material.
We wrote about this last month, but the scare seems to have developed a life of its own, as often happens with internet stories.
So we went in search of more information which could educate us all further. The following key messages were issued by the European plastics association, Plastics Europe:
- Polystyrene is a multifunctional plastics material which has been used in the packaging and insulation industry sectors since the early 1950’s. It is the preferred packaging material for many dairy and fresh food products increasing shelf life and making transportation and storage easier.
- Polystyrene is produced by the polymerisation of styrene, a substance which also occurs naturally in foods such as strawberries, beef, coffee beans and cinnamon.
- Styrene has been approved for use in food contact applications by the European Food and Safety Authority (EFSA)
- Potential effects on the environment and human health have been examined for the whole lifecycle use of polystyrene and it has been concluded that there is no need for any restrictions in the application and use of styrene based materials, such as polystyrene, in food packaging applications.
- Styrene is produced from benzene which is regarded as a human carcinogen. Polystyrene producers have therefore set strict specifications for styrene monomer purity including residual benzene content. Current state-of-the art analytical measuring techniques and extensive testing are unable to detect its presence.
- Benefits food preservation & transportation
Polystyrene is a multifunctional plastics material which has been used in the packaging and insulation industry sectors since the early 1950’s. Polystyrene is the preferred packaging material for many dairy and fresh food products. For example, yoghurt cups, ice cream containers and fresh fruit trays are made from polystyrene. The packaging is strong, light and stable. It increases the shelf life of food keeping it fresh and making it easy to transport and store.
Chemically, polystyrene is produced by the polymerisation of styrene resulting in a highly stable material. As well as being produced on an industrial scale, styrene also occurs naturally in foods such as strawberries, beef, coffee beans and cinnamon.
Styrene has been approved for use in food contact applications by the European Food and Safety Authority (EFSA) which is responsible for consumer health and safety. All components used to make food contact materials have to pass this scientific evaluation and need approval from EFSA. EFSA investigates all available scientific data, specifically looking into potential effects in relation to realistic human exposure.
Manufactured styrene identical to natural
An analysis of the migration of styrene from polystyrene into food has been found to be very low and human exposure is therefore presumed to be negligible and EFSA has therefore so far seen no need to establish a maximum tolerable daily intake (TDI) limit. This is probably also because it is impossible to distinguish between manufactured styrene and naturally occurring styrene in the body as they are chemically identical.
In addition, during the past decade, styrene has been comprehensively investigated under European chemical regulatory processes (1) over its whole life cycle from production over processing, application and use to its disposal. Potential effects on the environment and human health were examined, taking into account inherent properties, toxicological, reproductive and developmental parameters as well as realistic exposure. A scientific expert committee assessed the data provided by manufacturers, authorities and scientists and came to the conclusion that styrene is not anticipated to be a human carcinogen. In its draft report it concluded that based on the comprehensive scientific material available there is no need for any restrictions in the application and use of styrene based materials, such as polystyrene, in food packaging applications.
Styrene is produced via the intermediate ethyl benzene from benzene. Benzene itself is regarded as a human carcinogen by the United Nations International Agency for the Research on Cancer (IARC) and under EU regulatory processes. As benzene is used in the production of styrene it is theoretically conceivable that trace amounts of benzene could be present in polystyrene. However, the current state of the art analytical measuring techniques are unable to detect its presence.
Reinforcing this science, a study made by Plastics Europe failed to identify benzene as a food contaminant in migration/extraction experiments from polystyrene plastics, even though the conditions used significantly exceeded the real-life food contact conditions. Scientists are of the opinion that even if trace amounts of benzene were present in polystyrene entering as a contaminant of styrene, such low amounts would be likely to stay safely enclosed in the polymer and not be released outside.
Strict specifications for our protection
And to minimize any such theoretical risk, polystyrene producers have set strict specifications for styrene monomer purity including residual benzene content and manage the polymerisation process to remove all volatile compounds as far as possible.
In South Africa all types of polystyrene is fully recyclable. It’s up to us, the users, to ensure our polystyrene waste enters the recycling stream to be re-molded into new products.