Selection of materials for product design is a challenging task. Most of the essential raw materials we use are infinite resources. Materials such as anthracite, bauxite, beryllium, caoutchouc, chrome, coal, cobalt, diamonds, gold, indium, iron, manganese, nickel, platinum, silicon, silver, titanium, vanadium, water, crude oil, and natural gas are crucial for human life. Some of them are still abundant but others are not. They will all one day become rare if they cannot be reused and recycled. Thus, the use of recycled materi- als helps reduce environmental damage. Moreover, the mining of minerals such as tantalite (coltan), cassiterite (tin), gold and wolframite (tungsten) in the Democratic Republic of the Congo or adjoining countries is known to be used to finance conflicts. That’s why they are called Conflict Minerals.
Similarly, in diamond supply chains there are Conflict Diamonds or Blood Diamonds.
Materials such as arsenic, mercury, lead and phthalates that are used for making electronic devices are now being phased out by many manufac- turers because they are hazardous to human beings and the environment during the production or disposal processes. Manufacturing technologies used to process different raw materials may consume large amounts of water and energy, and also produce large amounts of air, liquid and solid emissions. Somehow, the selection of materials depends on the available manufacturing technologies. In various industries, managers ought to know that the applications of some substances help to meet product speci- fications but they are also hazardous. There are many types of hazardous substances:
●
● explosives;
●
● flammable substances;
●
● oxidizing agents and peroxide;
●
● toxic substances;
●
● substances causing diseases;
●
● radioactive substances;
●
● mutant-causing substances;
●
● corrosive substances;
●
● irritating substances;
●
● other substances, chemical or otherwise, which may cause injury to human beings, animals, plants, property, or environments.
Table 5.1 List of common hazardous materials
Materials Common usage Environmental and social impacts
Acid and alkalis They are used for various cleaning processes and the production of chemicals.
Highly corrosive liquids used in industry that can corrode metals and destroy tissues of living organisms.
Arsenic It is used as an alloy in lead shot and electrical circuits, as a pesticide, and as a preservative for wood. It is used in the microchip industry and copper production industry.
It is highly toxic and carcinogenic. People who work with pesticide and wood preservative can be exposed to arsenic. It may cause infertility, miscarriages, skin problems and brain damage.
Asbestos It was once widely employed in construction primarily for insulation. It is still used to make gaskets, brakes, roofing and other materials.
When inhaled it can cause lung cancer and mesothelioma.
Cadmium It is used in batteries, pigments, metal coatings, and plastics. It is also used in nuclear power plants. It is produced from the smelting of zinc.
Exposure risks are from metal refinery factories, cigarette smoke and contaminated foods. Breathing cadmium can damage lungs and kidneys, and cause infertility and cancer.
It can pollute surface water and poison earthworms and soil organisms.
Chromium It is used as a rust-resistant coating on other metals, a pigment in paint, and in wood preservatives and liquids for tanning hides. It is also used for leather and textile production.
People who smoke or work in the steel and textile industries can be exposed to chromium compounds. They may experience skin and respiratory problems, kidney and liver damage and lung cancer. Chromium can be toxic to organisms.
Clinical wastes Hospitals must dispose of large quantities of syringes, medication baffles and other materials.
Can be infectious and spread pathogens and harmful micro-organisms.
Cyanide Compressed hydrogen cyanide gas is used to exterminate rodents and insects on ships and to kill insects on trees.
In large doses can cause paralysis, convulsions and
respiratory arrest. Chronic exposure to low doses can cause fatigue and weakness.
Dimethyl fumarate (DMFu)
Used as a biocide in furniture and shoes to prevent the growth of mould during transport.
Skin allergies.
Lead Used in the production of batteries, ammunition, paints, metal products such as solder and pipes, and devices to shield X-rays.
If ingested or inhaled can harm the nervous system, kidneys, and reproductive system.
Mercury Used to produce chlorine gas, caustic soda, thermometers, dental fillings, and batteries.
Exposure occurs through contaminated air, water and food and through dental and medical treatments. High levels may damage the brain, kidneys, and developing foetuses.
PCBs Compounds used in industry as heat exchange fluids, in electric transformers and capacitors, and as additives in paint, carbonless copy paper, sealants and plastics.
Poses risks to nervous systems, reproductive systems, immune systems and livers.
POPs Persistent organic pollutants include aldrin, chlordane, chlordecone, dieldrin, dichlorodiphenyl - trichloroethane (DDT), endrin, heptachlor, hexachlorobenzene, hexachlorocyclohexane, lindane, mirex and toxaphene are commonly used in agriculture to control pests.
POPs are a class of chemicals and pesticides that persist for many years in the environment, are transported great distances from their point of release, bioaccumulate (thus threatening humans and animals at the top of the food chain), and cause a range of health effects.
PBB and PBDE Polybrominated biphenyls (PBB) were used to make products such as computer monitors, televisions, textile, plastic foams, etc. to make them difficult to burn. Polybrominated biphenyls ether (PBDE) is used for the same function.
Causes nausea, abdominal pain, loss of appetite, joint pain, fatigue and weakness, also possibly skin problems.
125
Table 5.1 provides a list of selected hazardous substances, most of which are identified by the essential directives and regulations on hazardous substances. Some of them are highly hazardous materials, which should be avoided. Some of them are banned in some countries but could be allowed in others.
Driven by regulations and/or sustainable development ambitions, most manufacturers have now established a list of banned and restricted materi- als, and another list of preferred materials. Proactive manufacturers such as HP and Dell have been updating a hazardous material watch list and assessing materials for future phase-out beyond the mandatory regulations.
These lists have to be integrated into the procedures and protocols of envi- ronmental management within the companies and supply chains. Standards such as ISO/IEC 17050-1:2004 can be used as it specifies general require- ments for a supplier’s declaration of conformity in cases when it is desirable or necessary (ISO, 2014). Many manufacturers nowadays specify their own supplier codes of conduct. There is also a need for an effective and inte- grated information system which facilitates the application and compliance of the material list so that the companies can design out hazardous and environmentally damaging substances as well as reducing the consumption of energy and other natural resources. Below is a case study illustrating how all these can be achieved.