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Frequently asked questions

Q: What is the formal definition of Polystyrene?
Polystyrene, sometimes abbreviated PS, is an aromatic polymer made from the aromatic monomer styrene, a liquid hydrocarbon that is commercially manufactured from petroleum
by the chemical industry. Polystyrene is a thermoplastic substance, normally existing in solid state at room temperature, but melting if heated (for moulding or extrusion), and becoming solid again when cooling off. Polystyrene is one of the most widely used kinds of plastic.
Pure solid polystyrene is a colourless, hard plastic with limited flexibility. It can be cast into moulds with fine detail, for example yogurt cups, plastic cutlery and CD and DVD cases. Polystyrene can be transparent or can be made to take on various colours. Products made from foamed polystyrene are nearly everywhere, for example packing materials, insulation, and foam beverage cups.

Q: What is styrene?
Styrene is a clear, colourless liquid that is derived from petroleum and natural gas by-products, but which also occurs naturally in food such as coffee, strawberries and cinnamon. Styrene helps create plastic materials used in thousands of remarkably strong, flexible, and lightweight products, which represent a vital part of our health and well being.
It's used in everything from food containers and packaging materials to cars, boats, and computers. The styrene used in these products is synthetically manufactured in petrochemical plants.

Q: What are CFC's?
CFC's, or chlorofluorocarbons, is commercially, the most important CFC's that is derivatives of methane and ethane. CFC's were first introduced in the 1930s as safe replacements for refrigerants such as sulfur dioxide, ammonia, chloroform, and carbon tetrachloride. These uses eventually resulted in large emissions of CFC's into the atmosphere.

Because of their low chemical reactivity, CFC's typically have long atmospheric residence times, and as a consequence are distributed globally. However, when CFC's reach the stratosphere they break down to release chlorine atoms. The chlorine atoms then react with
stratospheric ozone, breaking it down into oxygen.

As ozone absorbs much of the sun's ultraviolet radiation, decreased stratosphere ozone levels could lead to increased ground-level ultraviolet radiation. This could adversely affect crop growth, and also lead to increases in cataracts and non-melanoma skin cancer.

CFC's are therefore now banned because they are the cause of the holes that grew in the ozone layers over the planets polar regions.

The banning of CFC's has lead to research to identify other chemicals that can be used in
the same applications but without the same environmental concerns.

Q: Is it safe to heat food in a plastic container in the microwave?
Rumours about the safety of using Polystyrene (also known as the brand name Styrofoam) in microwaves have circulated, stating that plastics form dioxins when heated in the microwave. This is completely untrue. For one thing, there is no reason for plastic containers to contain dioxin unless the purpose is to store dioxin and, important to note, dioxins typically form at temperatures above 370°C.

Contrary to popular belief, some Expanded Polystyrene (EPS) and other polystyrene containers, such as salad or yogurt containers, can safely be used in the microwave.
Just follow the same rule you follow for other plastic containers: Check the label.

Q: What is all the talk about ‘landfill space’?
For hundreds of years, people have used garbage dumps to get rid of their trash. Yesterday’s garbage dump was nothing more than a pit or field just outside of town where people left their garbage. Today, we still bury our garbage, although not in the open dumps of yesterday.
Most of our garbage is hauled off in garbage trucks and packed into sanitary landfills—making land filling.

The problem is that we, in South Africa, have a waste problem and we are running out of landfill (dumping) space at an alarming rate. Just in Cape Town, they dump a total of 6 000 tons of waste every day. To give you a better idea of how much space 6 000 tons of waste would take up, if you have a normal 3m x 2m room in your house, and you fill it up with waste all the way to the roof, you will have one ton of waste.

Q: Give me 4 good reasons why I should recycle?
  • We only have enough landfill space for the next 3 years and by the time that the last landfill site closes down; we would be building mountains of waste equivalent to 6 000 rooms per day.
  • One of the major contributors to greenhouse gasses (the gas in the atmosphere that prevents radiation from the earth to escape that in turn causes Global Warming) is Methane Gasses. Methane Gasses are mostly released from old landfill sites. Can you see how recycling will prevent Global Warming?
  • The materials that you recycle will go back into the production streams and it will save huge amounts of energy and raw materials.
  • It is the right thing to do!
Please go to our Polystyrene Recycling and Drop off sites page for more information.

Q: What products are made from recycled Polystyrene?
Polystyrene is not only versatile as a product, but also versatile in the recycling thereof. Products made from recycled Polystyrene include:
  • Coat hangers
  • Seedling trays
  • Curtain rods, finials and holdbacks
  • Cornices and skirtings
  • Outdoor furniture
  • Poles and decking

Questions and Answers

What is styrene?
Styrene is a liquid that is derived from petroleum and natural gas by-products, but which also occurs naturally. Styrene helps create plastic materials used in thousands of remarkably strong, flexible, and lightweight products that represent a vital part of our health and well being. It's used in everything from food containers and packaging materials to cars, boats, and computers. The styrene used in these products is synthetically manufactured in petrochemical plants. However, styrene also occurs in the environment and is a natural component of many common foods, such as coffee, strawberries and cinnamon. Some people confuse styrene, which is a liquid, with polystyrene, which is a solid plastic made from polymerised styrene. Styrene and polystyrene are fundamentally different. Polystyrene is inert, and has no smell of styrene, therefore polystyrene often is used in applications where hygiene is important, such as health care and food service products.

Is styrene present in polystyrene?
Very small amounts of styrene monomer that was not converted into polystyrene during processing do remain in finished polystyrene products. Numerous studies and investigations have been carried out to determine if there is a safety concern regarding the amounts of styrene that remain in polystyrene resins. The results of these studies indicate that polystyrene is safe for use in food-contact products. Styrene is approved for use as a starting material for the production of polystyrene food and beverage packaging by regulatory agencies worldwide. The European Food Safety Authority has not assigned a so called 'Specific Migration Limit' to styrene. Many surveys made from e.g. the UK Ministry of Agriculture, Food and Fisheries (MAFF) in the late 90-ies gave complying values for food packaged in polystyrene. This survey was repeated in 2003 and gave again complying values.
For more information see link: www.food.gov.uk/news/newsarchive

Do I come into contact with styrene?
Styrene is a natural component of some foods, and is present in small amounts in foods such as cinnamon, beef, coffee beans, peanuts, wheat, oats, strawberries, and peaches. Most people are exposed to styrene in tiny amounts that may be present naturally in the diet, air (styrene is a component of cigarette smoke,gasoline and fuel exhausts, and, in trace quantities, as a result of using food-service packaging). Scientific studies have shown that the very small amount of styrene that people may be exposed to from packaging is about the same amount as comes from naturally-occurring styrene in foods. These studies have also shown that these levels of exposure are safe and should not be a cause for concern.

Is styrene harmful to my health?
Styrene is harmless in the very small amounts most people might normally encounter in air or food. The general public is very unlikely to encounter high levels of styrene. In fact, styrene is approved by the US Food and Drug Administration as a food additive. Major studies in Japan, United States and Europe have shown that even at very exaggerated levels of exposure, the oligomers (combination of two or three styrene molecules) that can migrate from polystyrene did not show an estrogenic effect.

For those directly working with the product (i.e. professional users, the people involved in the conversion of styrene into the final items we use in the everyday life), the relevant safety measures are provided by means of a Safety Data Sheet. Governments and Industry have set safe exposure limits for professional workers.

As part of a continuing effort to protect health and the environment, the European Union and the U.S. Environmental Protection Agency are both currently conducting formal reviews that will provide safety assessments of the scientific data on styrene.

What about the odour of styrene?
Styrene's distinctive odour can be detected even when styrene is present at extremely
l low levels - levels that are many, many times below any level that may result in a possible
health effect.

Is there a concern about a risk of cancer??
Styrene is currently under European risk assessment to investigate its impact on the environment and human health. The general population incurs no detectable risk resulting from styrene exposure. Existing work place exposure limits represent a satisfactory precautionary measure to protect styrene-exposed workers.
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