Study: Workplace Pesticide Exposure Linked With COPD Risk

Investigators analyzed 12 categories of workplace agents, but only the composite category of pesticides was found to be linked with developing chronic obstructive pulmonary disease.

A new analysis of occupational hazards suggests exposure to pesticide is significantly associated with a heightened risk of developing chronic obstructive pulmonary disease (COPD).

The report is based on nearly 100,000 participants in a British population-based cohort. The study findings were published in the journal Thorax.

Corresponding author Sara De Matteis, MD, MPH, PhD, and colleagues had previously examined whether specific occupations might be linked to the risk of COPD. They consulted the UK Biobank database and were able to identify 6 occupations that appeared to heighten COPD risk.

In the new report, the authors aimed to see whether they could figure out which particular job-related exposures might be causing the increased risk associated with the different occupations.

De Matteis and colleagues utilized the ALOHA job exposure matrix (ALOHA+JEM), which was developed by industrial hygienists, and which documents the prevalence of exposure to potentially harmful agents among different jobs.

The authors looked at 12 agents and compared exposure rates to job data and COPD rates among the 94,514 patients in the biobank for whom sufficient spirometry, smoking data, and job histories were available. Of those, 56% were women, the patients had an average age of 56 years, and 58.8% had no history of smoking. Just 5.6% of people in the study reported being current smokers.

Overall, 8.0% of patients in the cohort had spirometry-defined COPD, although rates were much higher among current smokers vs never-smokers (16.8% vs 6.9%).

When examining workplace exposures to agents, the authors found significant overlap between exposures; many patients were exposed to multiple agents over the course of their careers.

Because of this, and due to a lack of significant data among subgroups of particular types of pesticides, the authors combined subgroups of pesticides (herbicides, fungicides, and insecticides) into a single category.

The most prevalent category of workplace exposure was the composite category of vapors, gasses, dust, and fumes (VGDF), to which nearly half of the workers with COPD (47.6%) and without (46.9%) were exposed. Most workers only had low-level exposure, and no statistically significant link was found with COPD rates, the authors said.

Just 4.2% of people with COPD and 3.5% of people without were exposed to pesticides at their workplaces. However, the authors found a significant link between pesticide exposure and COPD risk.

The prevalence ratio for COPD among people exposed to pesticides was 1.13 (95% CI, 1.01-1.28) and those with high cumulative exposure had a prevalence ratio of 1.32 (95% CI, 1.12-1.56). The finding was confirmed among non-smokers and non-asthmatics.

The authors said these new results were consistent with their earlier research examining COPD risk based on job titles. Among the jobs with the highest risk were gardeners, groundskeepers, and park-keepers, among others.

“The findings of this study (elevated risk associated with pesticides, but not with other agents) reinforce our previous job title analyses and support the hypothesis that pesticides may affect the risk of COPD,” they wrote.

De Matteis and colleagues concluded that their large sample size and the confirmatory sensitivity analysis make a strong case for the link between pesticides and COPD. However, they said their inability to analyze the risks associated with particular types of pesticides is a shortcoming that warrants further investigation.

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