By Sue Kedgley, July 2, 2014
Two years ago the International Agency for Research on Cancer
categorised diesel exhaust fumes as class one carcinogens in the same
category as asbestos, arsenic and cigarette smoke.
It said the
scientific evidence about the harm of diesel exhaust fumes was
compelling and its conclusion was that "diesel engine exhaust causes
lung cancer in humans".
The reason is that when diesel burns
inside an engine it releases particles that stay in the airways and can
trigger asthma, bronchitis and other lung conditions, including cancer.
tiniest particles can penetrate the cells of lungs, enter the
bloodstream, deliver toxins to internal organs, affect blood vessels and
contribute to heart attacks and strokes.
Children are especially
at risk from particulates in diesel exhaust fumes because their organs
are still developing and they have a faster breathing rate.
The agency, part of the World Health Organisation, says diesel fumes
are as carcinogenic as second-hand cigarette smoke, and has called for
urgent global action to reduce exposure.
You would expect a
flurry of governmental action in the wake of this rather startling
announcement. For while it's possible to avoid second-hand smoke from
tobacco, it's almost impossible to avoid exposure to diesel fumes.
of our buses and trucks are powered by diesel and the number of diesel
cars has risen steadily from 11 per cent of our fleet in 2000 to 17 per
cent in 2013. We have one of the oldest, and therefore most polluting,
diesel vehicle fleets in the western world.
Most of us are
exposed to diesel fumes whenever we walk, cycle or drive in an urban
environment. Almost all of us are exposed to diesel fumes on a daily
basis, which is why it's such a serious public health issue.
far, however, there's been no discernible response from the Government
to the WHO announcement. Sure, sulphur levels in diesel were reduced
some years ago, and emissions standards for new vehicles tightened in
2008. But these standards only apply to new vehicles since 2008.
though tighter emissions standards for diesel vehicles reduce nasty
emissions such as nitrogen oxides, they don't get rid of the tiny,
carcinogenic particulates at the core of health concerns about diesel
engines. Nor do they reduce the carbon that diesel engines emit.
cities around the world are switching to electric-powered public
transport, such as light rail and electric buses, because they are
concerned about the health effects of diesel exhaust and want to make
public transport and the urban environment more attractive.
in New Zealand, where about half our buses were made before 2003 and are
dirty and polluting, there's been no similar move - other than the
introduction of electric trains into Auckland.
Auckland has so
far rejected light rail as a public transport option, while the
Wellington Regional Council, incomprehensibly, is proposing to scrap its
fleet of 60 clean, zero-emitting, climate-friendly electric trolley
As harmful emissions from diesel buses continue to pollute
our inner cities, making them unhealthy and unattractive environments,
surely it's time for a rethink.
Auckland has the worst air
quality in Australasia and is twice as polluted as Sydney. A recent
global report on air pollution found 23 sites in Auckland with dangerous
levels of carcinogenic particulates caused by diesel emissions.
level of air pollution is not only dangerous and unacceptable, it's
costing us dearly. Auckland Council estimates the health costs of air
pollution at about $465 million a year. Mayor Len Brown recently
suggested that the pollution in Auckland is so bad the underground city
rail link needs to be sped up to reduce the fumes.
that. But surely if he is serious about reducing diesel pollution, it's
also time to ditch its fleet of dirty, polluting buses, and replace
them, over time, with zero-emitting electric buses or light rail.