# Evaluation of health effect on workers exposed to methyl bromide with prefrontal event-related potential

## TL;DR

This study shows that methyl bromide exposure affects cognitive health in workers, even when they show no symptoms.

## Contribution

The study reveals new evidence of methyl bromide's cognitive impact using ERP and bromide ion measurements.

## Key findings

- ERP changes in fumigators were not significant after MB exposure, suggesting cognitive impairment.
- Urinary bromide ion levels in fumigators increased sharply after work, indicating exposure.
- Inspectors showed significant ERP changes and no bromide increase, contrasting with fumigators.

## Abstract

Methyl bromide (MB) is a potent fumigant used to control pests in soil and agricultural products. As an ozone-depleting substance, MB has been largely replaced by safer alternatives. MB is highly toxic to humans and has been shown to adversely affect asymptomatic workers’ central and autonomic nervous systems and vascular health. However, its impact on perceptual and cognitive abilities remains underexplored. In this study, we examined the effects of MB exposure on cognitive functions in asymptomatic workers. Event-related potential (ERP) indices, which reflect perceptual and cognitive processes, and urinary bromide ion (Br-) concentrations were assessed in 32 fumigators (study group) and 18 inspectors (control group) before and after fumigation. Post-work ERP latency and amplitude changes in inspectors were significant (P < 0.01), similar to those observed in healthy individuals. In contrast, ERP changes in fumigators were not significant compared to pre-work values; this suggests that MB negatively impacts cognitive health. Additionally, Br‑ levels in fumigators rose sharply after work (P < 0.001), while inspectors showed no such increase. The elevated Br- levels and nonenhanced ERP indices in fumigators after MB exposure indicate adverse health effects despite the absence of symptoms.