attached
This study assesses the distribution of
goiter in the Kalutara District, Sri Lanka in order to
find causative factors for the occurrence of goiter even
after the salt iodization. A questionnaire survey was
conducted at the household level and at the same time
iodine and selenium levels of the water sources were
analyzed. Questionnaire survey results indicated the
highest numbers of goiter patients in the northern part
where the lowest were found in the southern sector
which may be due to the presence of acid sulfate soils.
Females were more susceptible and it even showed a
transmittance between generations. Average iodine
concentrations in subsurface water of goiter endemic
regions are 28.25 ± 15.47 lg/L whereas non-goiter
regions show identical values at 24.74 ± 18.29 lg/L.
Surface water exhibited relatively high values at
30.87 ± 16.13 lg/L. Endemic goiter was reported in
some isolated patches where iodine and selenium
concentrations low, latter was\10 lg/L. The formation of acid sulfate soils in the marshy lands in
Kalutara district may lead to transformation of
biological available iodine oxidation into volatile
iodine by humic substances, at the same time organic
matter rich peaty soil may have strong held of iodine
and selenium which again induced by low pH and high
temperature were suggested as the instrumental factors in the endemic goiter in Kalutara district. Hence,
geochemical features such as soil pH, organic matter
and thick lateritic cap in the Kalutara goiter endemic
area play a role in controlling the available selenium
and iodine for food chain through plant uptake and in
water.
