Læknablaðið - 15.12.1989, Side 10

386
LÆKNABLAÐIÐ
eftir því sem starfsaldur í verksmiðjunni
var lengri. Dánarhlutfall vegna krabbameina
var tölfræðilega marktækt hjá þeim, sem
höfðu unnið styst. Hér er því ekki um að
ræða »skammtur-svörun« (dose-response)
samband heldur hið gagnstæða. Það bendir
til, að skýringanna sé ekki að leita í þessu
vinnuumhverfi, en ástæðumar eru okkur ekki
ljósar.
Athuganir á lífsháttum mismunandi
þjóðfélagshópa eru óplægður akur á íslandi.
Rannsóknir frá Englandi og Wales sýna,
að dánarhlutfall vegna krabbameina er
mismunandi hjá þjóðfélagsstéttum (33).
Þeir, sem hafa athugað starfsmenn í
áburðarverksmiðjum, hafa meðal annars rætt
hugsanlegt vægi lífshátta og þjóðfélagsstöðu
(19). Islenski draumurinn er á þann veg, að
á Islandi sé stéttlaust þjóðfélag, en kannanir
hafa leitt í ljós, að það er aðeins draumur
(34). A hinn bóginn er talið, að stéttaskipting
á Islandi sé fyrst og fremst byggð á menntun
en ekki efnahag (34). Það má spyrja sig
þeirrar spumingar, hvort þeir, sem standa
stutt við í vinnu, hafi aðra lífshætti en þeir,
sem eru lengur á sama stað, eða hvort þeir,
sem unnu innan við eitt ár við vélgæslu í
Aburðarverksmiðjunni voru á einhvem hátt
veikbyggðari en hinir og þoldu vinnuna verr.
Athugunin hefur því vakið aðrar spumingar
en lagt var upp með, en svaranna væri vert að
leita.
Þakkir: Höfundar vilja þakka Runólfi
Þórðarsyni og Víði Kristjánssyni fyrir
upplýsingar og aðstoð.
SUMMARY
Mortality among employees in a fertiliser plant in
Iceland.
A retrospective cohort study was done on
employees in a fertiliser factory. The aim of
the study was to assess the risk of stomach- and
lungcancer. The cohort comprised 603 subjects
and their death rates were compared with those
of the general male population in Iceland. The
study period was 1954 to 1985. The results do
not give any evidence of an excess of deaths from
stomach- or lungcancer. Total mortality was lower
than expected and even lower when the analysis
was restricted to those who had worked more than
one year. Shiftwork operators had the highest
SMRs, however, with a reverse dose-response
according to duration of employment, indicating
that this might be due to factors unrelated to
fertiliser manufacturing. As these factors life-style
and social classes are mentioned, besides possible
selection of weaker subjects to this assumed easy
work.
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