||Occurrence in e-waste
|– PCB (polychlorinated biphenyls)
|– TBBA (tetrabromo-bisphenol-A)
– PBB (polybrominated biphenyls)
– PBDE (polybrominated diphenyl ethers)
|Fire retardants for plastics (thermoplastic components, cable insulation)
TBBA is presently the most widely used flame retardant in printed wiring boards and casings.
|– Chlorofluorocarbon (CFC)
||Cooling unit, Insulation foam
|– PVC (polyvinyl chloride)
|Heavy metals and other metals:
||Small quantities in the form of gallium arsenide within light emitting diodes
||Getters in CRT
||Power supply boxes which contain silicon controlled rectifiers and x-ray lenses
||Rechargeable NiCd-batteries, fluorescent layer (CRT screens), printer inks and toners, photocopying-machines (printer drums)
|– Chromium VI
||Data tapes, floppy-disks
||CRT screens, batteries, printed wiring boards
||Fluorescent lamps that provide backlighting in LCDs, in some alkaline batteries and mercury wetted switches
||Rechargeable NiCd-batteries or NiMH-batteries, electron gun in CRT
|– Rare Earth elements (Yttrium, Europium)
||Fluorescent layer (CRT-screen)
||Older photocopying-machines (photo drums)
|– Zinc sulphide
||Interior of CRT screens, mixed with rare earth metals
|– Toner Dust
||Toner cartridges for laser printers / copiers
||Medical equipment, fire detectors, active sensing element in smoke detectors
What some of these substances can do to you
Beryllium has recently been classified as a human carcinogen because exposure to it can cause lung cancer. Workers who are constantly exposed to beryllium, even in small amounts, and who become sensitised to it can develop what is known as Chronic Beryllium Disease (beryllicosis), a disease which primarily affects the lungs. Exposure to beryllium also causes a form of skin disease that is characterised by poor wound healing and wart-like bumps.
Brominated flame retardants (BFR�s)
Combustion of halogenated case material and printed wiring boards at lower temperatures releases toxic emissions including dioxins which can lead to severe hormonal disorders.
Cadmium components may have serious impacts on the kidneys. Cadmium is adsorbed through respiration but is also taken up with food. Due to the long half-life in the body, cadmium can easily be accumulated in amounts that cause symptoms of poisoning. Cadmium shows a danger of cumulative effects in the environment due to its acute and chronic toxicity. Acute exposure to cadmium fumes causes flu-like symptoms of weakness, fever, headache, chills, sweating and muscular pain. The primary health risks of long term exposure are lung cancer and kidney damage. Cadmium also is believed to cause pulmonary emphysema and bone disease (osteomalacia and osteoporosis).
When released into the atmosphere, they accumulate in the stratosphere and have a deleterious effect on the ozone layer. This results in increased incidence of skin cancer in humans and in genetic damage in many organisms.
While some forms of chromium are non toxic, Chromium (VI) is easily absorbed in the human body and can produce various toxic effects within cells. Most chromium (VI) compounds are irritating to eyes, skin and mucous membranes. Chronic exposure to chromium (VI) compounds can cause permanent eye injury, unless properly treated. Chromium VI may also cause DNA damage.
Dioxins are known to be highly toxic to animals and humans because they bio-accumulate in the body and can lead to malformations of the fetus, decreased reproduction and growth rates and cause impairment of the immune system among other things.
Short-term exposure to high levels of lead can cause vomiting, diarrhea, convulsions, coma or even death. Other symptoms are appetite loss, abdominal pain, constipation, fatigue, sleeplessness, irritability and headache. Continued excessive exposure, as in an industrial setting, can affect the kidneys. It is particularly dangerous for young children because it can damage nervous connections and cause blood and brain disorders.
Mercury is one of the most toxic yet widely used metals in the production of electrical and electronic applications. It is a toxic heavy metal that bioaccumulates causing brain and liver damage if ingested or inhaled.
Polychlorinated biphenyls (PCBs)
PCBs have been shown to cause cancer in animals. PCBs have also been shown to cause a number of serious non-cancer health effects in animals, including effects on the immune system, reproductive system, nervous system, endocrine system and other health effects. PCBs are persistent contaminants in the environment.
Polyvinyl chloride (PVC)
PVC is hazardous because it contains up to 56 percent chlorine which when burned produces large quantities of hydrogen chloride gas, which combines with water to form hydrochloric acid and is dangerous because when inhaled, leads to respiratory problems.
Exposure to high concentrations of selenium compounds cause selenosis. The major signs of selenosis are hair loss, nail brittleness, and neurological abnormalities (such as numbness and other odd sensations in the extremities).
Information obtained from The Agency for Toxic Substances and Disease Registry of the U.S. Department of Health and Human Services.