Hazardous Materials and their Effects on Humans and the Environment
Lead
Lead is known to cause damage to the central and peripheral nervous systems, blood system and kidneys in humans. Effects on the endocrine system have also been observed and its serious negative effects on children's brain development are well documented. Lead accumulates in the environment and has high acute and chronic toxic effects on plants, animals and microorganisms. The main concern in regard to the presence of lead in landfills is the potential for the lead to leach and contaminate drinking water supplies. The main applications of lead in computers are:
* (1) Soldering of printed circuit boards and other electronic components
* (2) Glass panels in computer monitors and TV's (cathode ray tubes)
Cadmium
Cadmium compounds are classified as toxic with a possible risk of irreversible effects on human health. Cadmium and cadmium compounds accumulate in the human body, in particular in kidneys. Cadmium is absorbed through respiration but is also taken up with food. Due to the long half-life (30 years), 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.
In electrical and electronic equipment, cadmium occurs in certain components such as chip resistors, infrared detectors and semiconductors. Older models of cathode ray tubes contain cadmium. Cadmium is also used as a plastic stabilizer.
Mercury
When inorganic mercury is introduced into natural water systems, it is transformed into Methylated mercury in bottom sediments. Methylated mercury easily bio-accumulates in living organisms. Methylated mercury causes chronic damage to the brain. It is primarily used in thermostats, (position) sensors, relays and switches (e.g. on printed circuit boards and in measuring equipment) and discharge lamps. It is also used in medical equipment, data transmission, telecommunications, and mobile phones. Mercury is also used in batteries, switches/housing, and printed wiring boards.
Hexavalent Chromium (Chromium VI)
Some manufacturers still use this substance as corrosion protection of untreated and galvanized steel plates, and as a decorative or hardener for steel housings. Chromium VI easily passes through cell membranes and is then absorbed - producing various toxic effects within contaminated cells. It causes strong allergic reactions in even small concentrations. Asthmatic bronchitis is a typical allergic reaction linked to Chromium VI. Chromium VI may also cause DNA damage. In addition, hexavalent chromium compounds are toxic in the environment.
Plastics
It is estimated that the largest volume of plastics used in electronics manufacturing (at 26%) is polyvinyl chloride (PVC), which creates more environmental and health hazards than most other types of plastic (see below).
PVC
The use of PVC in computers is mainly found in cabling and computer housings. PVC is a difficult plastic to recycle. It contaminates other plastics in the recycling process. More importantly, the production and burning of PVC products generates dioxins and furans.
Brominated Flame Retardants
Brominated flame-retardants are a class of brominated chemicals commonly used in electronic products as a means of reducing flammability. In computers, they are mainly used in four applications: printed circuit boards, components such as connectors, plastic covers and cables. Various scientific observations indicate that Polybrominated Diphenylethers (PBDE) might act as endocrine disrupters.
What can we do?
Recycling of computer and television materials and components - when properly implemented - represents the safest and most cost-effective strategy for addressing the problems posed by these units when inoperative or outdated. Recycling TV and computer materials and components and removing and/or reducing and treating the hazardous components conserves resources, reduces environmental and public health threats, and protects worker safety, while substantially reducing the high cost of permanently storing and disposing of hazardous wastes in permitted hazardous waste facilities.
Summary
As technology continues its history of rapid advances, a growing mountain of obsolete computers and electronic equipment is a certainty. Using a safe controlled equipment recovery solution will ensure that none your technology will enter the waste stream. Together we can help develop a region where our environment and people are protected from harm with continued development and recognition at international standards.
- Source: Report on Poison PC's and Toxic TV's (www.cawrecycles.org)
