Associations between pesticide use and respiratory symptoms: A cross-sectional study in Southern Ghana

Background: Indiscriminate use of pesticides is a common practice amongst farmers in Low and Middle Income Countries (LMIC) across the globe. However, there is little evidence defining whether pesticide use is associated with respiratory symptoms. Objectives: This cross-sectional study was conducted with 300 vegetable farmers in southern Ghana (Akumadan). Data on pesticide use was collected with an interviewed-administered questionnaire. The concentration of seven organochlorine pesticides and 3 pyrethroid pesticides was assayed in urine collected from a sub-population of 100 vegetable farmers by a gas chromatograph equipped with an electron capture detector (GC-ECD). Results: A statistically significant exposure-response relationship of years per day spent mixing/applying fumigant with wheezing [30-60 days/year: prevalence ratio (PR)=1.80 (95% CI 1.30, 2.50); >60days/year: 3.25 (1.70-6.33), p for trend=0.003] and hours per day spent mixing/applying fumigant with wheezing [1-2 h/day: 1.20 (1.02-1.41), 3-5 h/day: 1.45 (1.05-1.99), >5 h/day: 1.74 (1.07-2.81), p for trend=0.0225]; days per year spent mixing/applying fungicide with wheezing [30-60 days/year: 2.04 (1.31-3.17); >60days/year: 4.16 (1.72-10.08), p for trend=0.0017] and h per day spent mixing/applying fungicide with phlegm production [1-2 h/day: 1.25 (1.05-1.47), 3-5 h/day: 1.55 (1.11-2.17), >5 h/day: 1.93 (1.17-3.19), p for trend=0.0028] and with wheezing [1-2 h/day: 1.10 (1.00-1.50), 3-5 h/day: 1.20 (1.11-1.72), >5 h/day: 1.32 (1.09-2.53), p for trend=0.0088]; h per day spent mixing/applying insecticide with phlegm production [1-2 h/day: 1.23 (1.09-1.62), 3-5 h/day: 1.51 (1.20-2.58), >5 h/day: 1.85 (1.31-4.15), p for trend=0.0387] and wheezing [1-2 h/day: 1.22 (1.02-1.46), 3-5 h/day: 1.49 (1.04-2.12), >5 h/day: 1.81 (1.07-3.08), p for trend=0.0185] were observed. Statistically significant exposure-response association was also observed for a combination of activities that exposes farmers to pesticide with all 3 respiratory symptoms. Furthermore, significant exposure-response associations for 3 organochlorine insecticides: beta-HCH, heptachlor and endosulfan sulfate were noted. Conclusions: In conclusion, vegetable farmers in Ghana may be at increased risk for respiratory symptoms as a result of exposure to pesticides.