Why are old electric goods harmful to the environment?

Click to enlarge picture

Every year 25 000 tons of electric equipment are imported into Latvia for household and business use. With time these appliances wear out and become waste. Many electric appliances contain substances harmful both to humans and to the environment and may cause irreversible damage. Hence the electric and electronic placed on the Latvian market are labelled with a special symbol – a container with a cross over it indicating that these goods cannot be disposed of together with household waste.
Why are electric and electronic appliances so harmful? How to they affect us? The hazardous elements contained in electric equipment may be divided into three main groups:

Chlorofluorocarbons
Chlorofluorocarbons (CFCs) or Freon is a group of chemical compounds that used to be widely used as a refrigerant in refrigerators and freezers during the mid and late 20th century and were easily obtainable and cheap. A side effect was discovered during the 1980s – if leaked into the environment CFC evaporates and rises to reach the ozone layer thus destroying the layer that protects the Earth from the ultra-violet rays of the Sun. The Vienna Convention for the Protection of the Ozone Layer (1985, entered into force in 1988) prohibits the use of CFCs in commodities and CFC is no longer used in refrigerators today.

Heavy metals
Heavy metals are compounds widely used in electronics, among them lead, Cadmium and Mercury. These metals are all around us in different compounds– as parts of electric appliances in TV-sets, computers, fluorescent lamps, etc. Similarly to refrigerators containing CFCs, if an electric appliance containing heavy metals are collected as household waste or dumped in the environment, it  rusts and leaks the harmful compounds that is absorbed by the environment and consequently by animals and humans.

Plastics
Almost all electric and electronic equipment contains a certain amount of plastic or polymer. Plastic/polymer is mainly used as casing, frames or other parts. Although the complete product is not harmful to people if handled according to the instruction for use, in certain conditions (e.g. if burned) an item containing plastic may become hazardous. Waste electric and electronic equipment is often dumped in suburban forests.  Forest fire or burning of last year grass may cause incomplete combustion of the plastic parts of the equipment triggering the separation of harmful and poisonous substances such as dioxins (one of the most dangerous cancerogenic organic compounds even at small doses) from polymers that contain many different additives (e.g. Chlorine, found in PVC window frames, insulating materials).  Besides, Chlorine only adds to the cancerogenic effect of dioxin. In total, the dangerousness of waste plastic goods is determined by the plastic compounds and additives. For instance, burning clean polyethylene has almost no impact on the environment, as it will only emit Carbon dioxin and water. But burning a PET bottle or a polymer bag will cause considerable damage to the environment, depending on the chemical additives.