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Ailments Surge as Ozone Hole Widens |
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By Stephen Leahy*
The
increase in skin cancer from sun exposure is alarming, scientists
say. Residents of southern Chile and Argentina are advised to take
extra care in protecting themselves from solar rays this spring
season in the southern hemisphere.
TORONTO, Nov 6 (Tierramérica) - Skin cancer,
eye lesions and other infections are on the rise, a reminder that
the Antarctic ozone hole continues to be a serious problem, especially
in southern Argentina and Chile, where ultraviolet radiation during
the spring months increases 25 percent.
The ozone layer covers the entire planet at an altitude of between
15 and 30 kilometers, and protects living organisms from the sun's
harmful rays.
According to the U.S. National Oceanic and Atmospheric Administration
(NOAA), the ozone hole over the Antarctic -- an annual phenomenon
-- sprawled to an average of 29.5 million square kilometers Sep.
21 to Sep. 30.
"This year's Antarctic ozone 'hole' is the largest on record," said
Achim Steiner, executive director of the United Nations Environment
Program (UNEP).
"Governments need to reduce and shut down the remaining sources
of ozone-depleting chemicals," Steiner said in a statement.
The rates of sunburn increase during the southern hemisphere springtime,
when the Antarctic ozone hole is large enough to extend over the
city of Punta Arenas at the southern tip of Chile, according to
studies conducted by Universidad de Magallanes.
Diagnoses of malignant melanoma, a deadly form of skin cancer, have
doubled in recent years, leading Chilean health authorities to recommend
avoiding direct exposure to the sun between 11:00am and 5:00pm,
and especially to protect children.
"Worldwide, the increases in melanoma are alarming. It is among
the fastest rising forms of cancer," says Edward De Fabo, an ultraviolet
(UV) radiation and skin cancer researcher at George Washington University,
in Washington, DC.
"It used to be rare in young people, but we see increasing cases
of melanoma in people under 25 years of age," De Fabo told Tierramérica
in an interview.
Increased rates of sunburn have also been linked to higher levels
of UV reaching the surface of the Earth. Direct adverse effects
of higher UV levels will be increases in skin cancer and increases
in cataracts and lesions in the eye, said Frank de Gruijl, a research
scientist at the University Hospital of Utrecht in the Netherlands.
"There are good reasons to suspect increases in herpes simplex virus
infections and other infectious diseases as well," de Gruijl told
Tierramérica.
Higher levels of ultraviolet B rays (the most harmful) have been
linked to the suppression of immune systems in humans, he said
Animals and plants are also affected by the seasonal expansion of
the ozone hole. Argentine scientists have found extensive DNA damage
to plants in Tierra del Fuego National Park, and Australian scientists
have documented reductions of phytoplankton up to 65 percent.
A bulletin on this year's ozone depletion, by the Australian Environment
Department's Antarctic Division, reports that an area of the far
South Atlantic known as the breadbasket of Antarctica was exposed
to three to six times the normal amount of UV radiation in October.
Global UV levels have been rising for the past 25 years and it is
not known how fast they will continue to increase, nor for how long,
said De Fabo. "Ozone-depleting chemicals are going to be in the
atmosphere for hundreds of years," he added.
The ozone was "virtually gone" in the atmospheric layer 12 to 20
kilometers above the earth's surface.
Worldwide, levels of UV radiation are on average five to ten percent
higher than pre-1980 levels, and will remain that way for another
decade or more.
These levels vary greatly, depending on location and time of year.
Countries closest to the equator have the highest UV exposure but
southern Argentina and Chile experience very high levels of UV --
25 percent higher -- during the spring, when the Antarctic ozone
hole opens.
Atmospheric scientists recently announced that the ozone layer is
beginning to recover and would be back to pre-1980 levels by 2050.
De Fabo points out that projected recovery, which has been pushed
back several times before, is dependent on full compliance with
the 1997 Montreal Protocol, which sets targets for phasing out production
and consumption of ozone-depleting substances.
These chemicals include halogenated hydrocarbons -- which contain
chlorine or bromide -- known for their role in breaking down the
three-oxygen ozone molecule.
Representatives from nearly 200 countries met Oct. 30-Nov. 3 in
New Delhi to track progress on the goals of the Protocol, which
"has been incredibly successful up till now, but there is much left
to do," UNEP spokesman Michael Williams told Tierramérica from New
Delhi.
Other issues discussed at the meeting were the illegal trade in
banned chlorofluorocarbons (CFCs), the continued use of methyl bromide
in the United States, and the fact that replacement chemicals (like
hydrochlorofluorocarbons, HCFCs, and hydrofluorocarbons, or HFCs)
worsens the other global atmospheric problem -- global warming --
by contributing to greenhouse gas emissions.
* Stephen Leahy is an IPS correspondent.
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