Workplace Pesticide Exposure Tied to Higher Risk of COPD, Suggests New Study

Occupational exposure to pesticides was linked to an increased risk of COPD in a large UK study.

Lifetime cumulative occupational exposure to pesticides was linked to an increased risk of chronic obstructive pulmonary disease (COPD) in a large UK study.

“Occupational exposures are important, preventable causes of COPD, and it has been recently estimated that about 14% of all cases are work-related,” wrote authors led by Sara De Matteis, MD, of the National Heart and Lung Institute at Imperial College in London, in the journal Thorax. “Identification of specific occupations and the underlying exposures associated with increased risk of COPD is key to preventing the associated public health burden, both in terms of morbidity and mortality and to focus preventive strategies.”

Previously, De Matteis in 2019 led the largest study to date investigating occupational COPD, which identified agriculture, fishing and groundskeeping, among others, as occupations associated with increased risk of COPD.

To follow up on those 2019 findings, De Matteis and colleagues invited over 300 000 UK Biobank study participants to complete an online job history timeline. Of the 116 375 participants who completed the form, 94 514 (55.8% women, mean age, 56 years) had acceptable/repeatable spirometry and smoking data and were included in the final analysis.

Investigators applied the ALOHA+ job exposure matrix (JEM) based on the International Standard Classification of Occupations codes, where exposure to 12 agents was rated as zero for no exposure, 1 for low exposure, and 2 for high exposure, according to the study.

More than half (58.8%) of all participants were never-smokers, and only 5.6% were current smokers. The prevalence of spirometry-defined COPD was 8.0%, and the frequency of COPD was higher among current smokers (16.8%) than among former smokers (8.6%) and never-smokers (6.9%).

A relatively small percentage of participants were exposed to pesticides: 4.2% of those with COPD and 3.5% of those without COPD. Exposure to vapors/gases/dusts/fumes was the most prevalent type of exposure, in 47.6% of those with COPD and 46.9% of those without COPD.

Results showed exposure to pesticides was associated with an increased risk of COPD for ever exposure (prevalence ratio [PR]=1.13; 95% CI, 1.01-1.28) and high cumulative exposure (PR=1.32; 95% CI, 1.12-1.56), with positive exposure–response trends (p trend=.004). This was confirmed in never smokers (p=.05) and persons without asthma (p=.001), added researchers.

De Matteis and colleagues noted that because it was an observational study, it cannot establish cause nor can the results pinpoint effects of specific pesticides on participants.

“Future studies focused on evaluating the effect of specific types of pesticides on chronic airway obstruction are warranted in order to inform focused workplace preventive strategies and avoid the associated COPD burden,” concluded investigators.

Reference: De Matteis S, Jarvis D, Darnton L, et al. Lifetime occupational exposures and chronic obstructive pulmonary disease risk in the UK Biobank cohort. Thorax. Published online January 26, 2022. doi: 10.1136/thoraxjnl-2020-216523.