Biomass is heavily depended on for domestic energy
use by people in developing countries. Combustion of
these materials produces a lot of smoke. Exposure to
this indoor air pollution has been linked to a number
of respiratory disorders. The aim of our study was
an assessment of the long-term respiratory effects of
indoor air pollution.
A survey was conducted in the riverine areas of the
Niger Delta of Nigeria among 521 fishermen exposed
to indoor air pollution from burning firewood and 545
matched controls. Exposure was determined by the
product of the average daily duration of time spent
close to the fire and the number of years (hours–years).
A modified British Medical Research Council (BMRC)
questionnaire was used to obtain information on respiratory
symptoms and spirometry was performed
on the participants.
The frequency of chronic respiratory symptoms was
significantly higher among the exposed fishermen
compared with the control subjects. Chronic bronchitis
was significantly associated with an obstructive ventilatory
pattern. Logistic regression analysis showed an
increased risk for chronic bronchitis among exposed
fishermen (OR 8.7; 95% CI 4.7–16.3, p<0.001); women
were six times more likely than men to develop chronic
bronchitis (OR 6.6; 95% CI 2.5-17.8, p< 0.001); and
cigarette smokers were five times more likely than
non-smokers to develop chronic bronchitis (OR 5.0;
95% CI 1.8–13.8, p<0.05).
The results of this survey showed an association
between exposure to indoor air pollution and chronic
respiratory disorders. Cigarette smoking aggravated
this association.