Náttúrufræðingurinn - 2011, Side 45

97
Tímarit Hins íslenska náttúrufræðifélags
Lokaorð
Nú er þekkt að háorkugeislun
getur valdið krabbameini, hjarta-
og æðasjúkdómum, ófrjósemi og
fleiri veikindum og vandamálum.
Frekari rannsókna er þörf til þess
að skilgreina betur áhættu tengda
geislavirkum samsætum og ann-
arri geislun. Umhverfisgeislun hefur
aukist síðustu áratugi vegna þynn-
ingar ósonlagsins, kjarnorkutilrauna,
-úrgangs og -slysa, fyrir utan aukna
almenningseign á raftækjum sem
einnig gefa frá sér geislun. Hafa
þarf í huga að hvort sem rætt er um
geislavirkar samsætur í náttúrunni,
röntgengeisla notaða í læknisfræði-
legum tilgangi eða geislameðferðir
með háorkugeislun, þá eiga þessar
mismunandi tegundir geislunar það
sameiginlegt að þær geta breytt
erfðaefni og leitt til frumudauða
eða krabbameinsmyndunar. Þessi
áhrif geta nýst í læknisfræðilegum
tilgangi ef rétt er farið með þau, en
án grunnrannsókna á sviði geisl-
unar og krabbameinslækninga fæst
ekki kunnátta til þess. Stór þekk-
ingargrunnur hefur þegar skapast
og verið notaður til að móta sam-
eiginlegar starfsreglur fyrir kjarn-
orkuver og alla starfsemi sem hefur
í för með sér geislunarhættu fyrir
fólk. Þessi þekkingargrunnur nýttist
vel í Fukushima, þar sem stjórnvöld
gátu brugðist hratt og vel við til
þess að vernda almenning fyrir
geislavirkum efnum í kjölfar spreng-
inganna sem þar urðu. Þó vantar enn
miklar upplýsingar og þá sérstak-
lega varðandi áhrif lágra skammta
háorkugeislunar þar sem þau koma
seint fram og aðrir umhverfisþættir
spila einnig inn í.
Summary
Biological effects of radiation
– Where and how
By now we know that high-energy
radiation can cause cancer, heart dis-
eases, infertility and other illnesses. In
the last decades, environmental radia-
tion has increased due to the depletion
of the ozone layer, nuclear tests,
-waste and -accidents, as well as an in-
creasing number of radiation emitting
electronics in public use. More re-
search is needed to define the risk
related to radiation, and it is important
to remember that the different ionising
radiation such as from the naturally oc-
curring radionucleides, X-ray for diag-
nostic purposes and γ rays in radiation
therapy can all ionize and change mol-
ecules such as DNA and thus cause
mutations, cell death or even cancer.
Ionising radiation can be used for med-
ical purposes if it is used correctly, but
without basic research in the field of
radiation and dosimetry the knowl-
edge needed for further progress and
increased safety will not be obtained. A
large knowledge base has already ac-
cumulated and is now used through a
system of radiation protection to create
routine work rules for nuclear power
plants and every operation concerning
ionising radiation. The knowledge al-
ready obtained on the effect of radia-
tion on the environment and the hu-
man body proved recently very useful
in Fukushima to limit public exposure
to external and internal radiation, upon
the nuclear accident which occurred in
March this year. Yet more research is
needed for a clearer picture of the ra-
diation damage on DNA and its effect
on humans.
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