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As the global population grew, and urban and industrial
development accelerated, the opportunities to dispose of materials,
including biodegradable ones, diminished while the quantities and nuisance
value of wastes increased. Society now has large volumes of waste to
deal with: in the United Kingdom, for example, more than 500 million
tons of waste are generated each year, of which some 30 percent are
mineral wastes, 20 percent industrial, 40 percent agricultural and 5
percent municipal. A sometimes inordinate focus on household waste has
often disguised the much larger volumes generated by up-stream activities
such as extraction, manufacture and distribution: it is often claimed
that for every ton of finished product, ten tons of wastes are created.
Laws to raise waste management standards were first
introduced at the beginning of the Certain wastes such as polychlorinated biphenyls
(PCBs), now phased out, and those from the nuclear industry take
many years to reach a state where they pose no further threat. Concern
about long-term harm has influenced disposal methods. We have learned,
in theory, how to manage landfill sites to contain leakage, and how
to seal radioactive waste in concrete tanks for safe, long-term storage.
We have developed combustion technologies to minimize emissions, and
found ways to clean those emissions. Yet despite the many advances,
disposing of waste is still problematic. Some potential disposal sites
are ruled out by geological factors and some by their distance from
the point of arising, but almost all are opposed by nearby residents.
Proposals to site a recycling collection point attract as much opposition
as those to construct a high-tech incinerator. We all want the goods
and services which industrialized society provides from power
supplies to computers, fast food to vitamin pills yet we do not
want the resulting waste to affect us as individuals. This is exacerbated
by mistrust of waste management systems and the risk of accident.
Industrial waste reflects not only the type of industry,
but also how efficiently it is operated, and whether clean technologies
are adopted. It is estimated that 26 percent of Europes waste
comes from manufacturing. In 1996, the United Kingdom generated 56 million
tons of manufacturing waste2.
These quantities are diminishing, but not fast enough to counteract
the rises caused by increased consumption. Pressure for industry to
reduce wastage comes from both internal and external economic drivers.
Producer responsibility initiatives already in place or proposed
for a range of goods from batteries and packaging to vehicles and electronic
equipment make industry responsible for its products after use,
and should result in fewer harmful components, as well as design decisions
which will make disassembly and recycling easier. Industrialization and level of affluence influence
both the composition and quantity of waste The link between affluence and municipal waste generation is surprisingly close: a 40 percent increase in the GDP of countries belonging to the Organisation for Economic Co-operation and Development (OECD) since 1980 has been accompanied by the same percentage growth in municipal waste. The OECD predicts that there will be a further 70 to 100 percent increase in GDP in its region by 2020. Unless the link between waste generation and GDP is severed, there could be a commensurate increase in waste. This is likely to be further exacerbated by certain social trends, such as the increase in single-person households due to higher divorce rates and the ageing population, particularly in the developed world. As the developing world industrializes and grows more affluent, it too can be expected to increase waste generation. How can the links be broken? Technological developments in materials
have already helped to reduce waste: food cans and glass milk bottles
are each half the weight they were 50 years ago. This, alongside new
materials, is reflected in the composition of household waste. In the
United States, for example, the combined percentage of glass and metals
in the waste stream diminished from 22 percent in 1970 to around 16
percent in 1990. Plastics rose from 2 percent to 9 percent, while paper
and card remained fairly constant at around 38 percent4.
By contrast, paper makes up just 5 percent of the waste in Ghana5.
Trial schemes which charge householders for the waste
they produce have raised awareness, although they have also thrown up
a few new problems, such as wastes being dumped by roadsides to avoid
the charges. The Swiss Environment Ministry reports that another method
of avoiding waste charges the burning of domestic refuse in gardens
or fireplaces is now the countrys biggest cause of dioxin
pollution. While the national emissions of dioxin from municipal incineration
facilities are just 16 grams per year, uncontrolled burning of waste
by householders emits between 27 and 30 grams of dioxin each year, despite
the fact that only 1 to 2 percent of Switzerlands municipal waste
is burned illegally, while 46 percent is burned in properly managed
plants. Sustainable development policies require us to take a more holistic view of waste and resources. We need to change attitudes, and to husband resources more carefully, particularly those which are finite. Observing the proximity principle and providing waste treatment and disposal facilities within a regions boundaries can do a great deal to reduce the environmental impact of managing waste.
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Copyright AAAS 2000. |