Smooth pursuit eye movements among storage battery workers

Area of Science:

• Occupational Health
• Neurotoxicology
• Clinical Neurology

Background:

• Lead exposure in battery storage plants poses risks to worker health.
• Elevated levels of blood lead and erythrocyte protoporphyrin indicate significant lead absorption.
• Subclinical neurological effects of lead poisoning are not always apparent through standard assessments.

Purpose of the Study:

• To investigate the impact of occupational lead exposure on the nervous system.
• To evaluate the utility of the Pendular Eye Tracking Test (PETT) in detecting lead-induced neurological dysfunction.
• To correlate eye movement abnormalities with biochemical markers of lead absorption.

Main Methods:

• A cohort of 11 male lead workers and 18 male controls were recruited.
• Lead exposure was assessed using blood lead, urinary lead, erythrocyte protoporphyrin, and delta-aminolevulinic acid levels.
• Smooth pursuit eye movements (SPEMs) were measured using an eye tracking technique and plotted on a polygraph.

Main Results:

• Lead workers exhibited motor coordination disorders in their SPEMs.
• The PETT revealed abnormalities in eye movement velocity and coordination.
• A correlation was observed between SPEM abnormalities and biochemical markers of lead exposure.

Conclusions:

• Occupational lead exposure can lead to subclinical damage of the nervous system, specifically affecting motor coordination.
• The PETT is a valuable tool for assessing neurological damage in lead-exposed individuals.
• Integrating PETT with biochemical data enhances the evaluation of lead poisoning's subclinical effects.