Waste refers to materials and substances that are of no further use and need to be disposed of. This includes bodily excretions from humans and animals, garbage, and wastes generated from commercial and industrial sources.
Waste can be a potential source of pathogens, an attraction for pests, a potential environmental hazard, as well as being unsightly and smelly. Waste management is therefore vitally important in protecting public health, protecting the environment, and maintaining waste-free, odour-free and comfortable public areas.
Bodily waste: Faecal matter can contain large amounts of viral and bacterial pathogens. The majority of illness in the world is caused by contact with faecal matter, either directly or via water. (Source 1)
2.5 billion people (38% of the world’s population) lack access to “improved sanitation” - the hygienic separation of human excreta from human contact - and 1.2 billion people have no sanitation facilities at all. (Source 2)
It is estimated that improved sanitation facilities could decrease the number of diarrhoea-related deaths for young children by more than one-third. About 1.4 million child deaths each year – approximately one in five of all child deaths – is due to diarrhoea. (Source 3) In Australia, high standards of sanitation not only save lives and prevent illness, but also help boost economic prosperity by increasing productivity and decreasing health care expenditure.
Solid waste: Garbage comes in many shapes and forms, some of which can be potential health hazards. For example, food scraps encourage the growth of pathogens and attract pests which can spread disease. Areas strewn with garbage are also less comfortable and enjoyable to be in.
Commercial and industrial waste: Commercial and industrial operations are highly diverse in nature. Some produce waste which needs to be properly managed in order to minimise pollution of the environment as well as any resulting negative impact on human health.
The Waste Management Hierarchy (right) prioritises practices that minimise the amount of waste that needs to be treated and disposed of.
However, arguments have been put forward that reuse or recycling of some materials may have more of an environmental impact, for example in terms of water and energy usage, than treatment and disposal. The issue is a complex one.
Regardless of the relative merits of these two approaches, some waste will inevitably need disposal.
In Australia, most cities and towns are serviced by municipal sewerage systems. These systems comprise sewer pipes to remove wastewater that is contaminated with bodily waste and other down-the-drain substances, and sewage treatment plants to treat the wastewater. More isolated locations may use septic tanks systems and sewage lagoons. All of these systems ensure that sewage is kept separate from drinking water, and that it is treated to a standard suitable for the final destination of the treated effluent.
Another destination for bodily waste is its disposal in nappies as municipal solid waste. Solid waste also includes food, paper products, plastics, household goods, construction materials and garden matter.
Most solid waste is put into landfill. There are strict environmental and health guidelines governing the operation of landfill areas to protect human health and the environment from potential issues such as emission of greenhouse gases, contamination of groundwater, and increased dust, litter, and pests.
“Contaminated waste” is a subset of solid waste that needs special care; for example, infectious waste generated by hospitals may be incinerated or chemically treated before being disposed of in landfill.
Commercial and industrial waste management is regulated under State & Territory legislation.
Source 1: Water Supply and Sanitation Collaborative Council (WSSCC) 2008, "A Guide to Investigating One of the Biggest Scandals of the Last 50 Years" http://esa.un.org/iys/docs/san_lib_docs/WASH_media_guide_en%5B1%5D.pdf
Source 2: UNICEF/WHO, 2008, Progress on Drinking Water and Sanitation: Special Focus on Sanitation, www.who.int/water_sanitation_health/monitoring/en/
Source 3: UNICEF/WHO, 2009, Diarrhoea: Why children are still dying and what can be done, http://whqlibdoc.who.int/publications/2009/9789241598415_eng.pdf