Introduction
The residents of Sonob village, located near a landfill in Oman, voiced concern about an increase in respiratory and other allergic diseases.
Methodology
A cross sectional study was conducted to study the effect of landfill gases on the health of the population of Sonob, as compared to four other villages selected from the same wilayat, by random cluster sampling technique. Information about self reported respiratory illnesses, allergic disorders, birth outcome and cancers was collected by door to door visit by local female volunteers using a structured questionnaire. Ambient levels of toxic gases were measured at the landfill site and selected villages.
Results
A total of 1213 persons were interviewed in the five villages, which showed very little demographic, socioeconomic and home environment variation. Generally, allergic respiratory and skin diseases with allergy or irritative pathogenesis, including dry cough, cough with sputum, difficulty in breathing, Bronchial asthma, Rhinitis, Bronchitis, conjunctivitis and Dermatitis increased the closer to the landfill. Sonob, which had the highest proportion of allergic diseases, showed twice the risk of allergy as compared to F. sham, 6.5 times the risk as compared to Hamam, 22 times the risk as compared to Aqbia, and 4 times as compared to gala. Concentrations of toxic gases had a strong inverse association with diseases as well as the distance from the landfill. Demographic, socioeconomic and home environmental factors showed no confounding effect on the relationship between allergic diseases and distance from the landfill. Ecological comparison also showed a significant relationship between concentration of toxic gases and allergic diseases, which was mitigated when controlled for distance from landfill.
Conclusion
Allergic diseases and emittent gases had an inverse relationship with the distance from the landfill, i.e. as the distance from landfill increased allergic disease decreased. Also, as the distance from the landfill increased, the concentration of toxic gases decreased.