The Relationship between Occupationally Exposed Arsenic, Cadmium and Lead and Brain Bioelectrical Activity-A Visual and Brainstem Auditory Evoked Potentials Study.

Marta Waliszewska-Prosół,Paweł Gać,Anna Szymańska-Chabowska,Rafał Poręba,Magdalena Koszewicz,Sławomir Budrewicz,Maria Ejma,Małgorzata Bilińska,Grzegorz Mazur

doi:10.3390/brainsci11030350

Marta Waliszewska-Prosół, Paweł Gać + Show 7 more

Open Access

https://doi.org/10.3390/brainsci11030350

Copy DOI

Journal: Brain sciences	Publication Date: Mar 10, 2021
Citations: 3	License type: CC BY 4.0

Affiliation: Wroclaw Medical University

Abstract

The aim of this study was to evaluate the parameters of visual and brainstem auditory evoked potentials in patients occupationally exposed to arsenic, cadmium and lead. The study group comprised 41 copper smelter and refinery workers (average age: 51.27) with occupational exposure to arsenic, cadmium and lead. The control group consisted of 36 healthy volunteers (35 men and 1 woman, aged 27–66, average age: 51.08). Neurological examination, brain imaging, and visual and brainstem auditory evoked potentials were performed, and the relationship between blood Cd, Pb concentration (Cd-B, Pb-B), blood zinc protoporphyrin (ZnPP), and urine As concentration (As-U) were assessed. In the workers, exceedances of allowable biological concentrations were observed, with the urinary concentration of arsenic being 5.2%, the cadmium and lead in blood being 1.3%, while the case of ZnPP was 2.6%. The mean P100, relative P100, and N145 visual evoked potential (VEP) latencies were significantly longer in exposed workers than in the controls. The mean wave III and V brainstem auditory evoked potential (BAEP) latency and the mean wave III–V and I–V interpeak latencies were longer, and the I and V amplitude was lower in the workers than the controls. In summary, occupational exposure to As, Cd, and Pb is associated with prolonged latency and reduced evoked potential amplitude, but As-U, Pb-B, Cd-B, and ZnPP concentrations are not linearly related to potential components. The analysis of evoked potentials may be a useful method of assessment of the central nervous system in patients with occupational exposure to heavy metals.

Highlights

Disorders resulting from chronic exposure to heavy metals affect various organs, including the nervous system
The criteria for inclusion in the group of persons professionally exposed to arsenic, cadmium, and lead were: current employment at workplaces with documented exposure to a steel mill according to the safety and health departments, a total period of work in positions with documented exposure to metals of at least 5 years, and lack of current professional exposure to other chemical and physical substances documented by foundry services responsible for work safety and hygiene
The average concentrations of blood cadmium, blood lead, and urine arsenic in the examined group of workers exposed to metals were 1.19 ± 1.40 μg/L, 181.85 ± 139.88 μg/L, and 15.60 ± 15.58 μg/g creatinine, respectively

Summary

Introduction

Disorders resulting from chronic exposure to heavy metals affect various organs, including the nervous system. The chronic neurotoxic effects of heavy metals are revealed in workers who are professionally exposed to them. Permanent exposure in the work environment can lead to absorption by the body and, to damage to the nervous system [1,2]. Knowledge about the molecular and biochemical mechanisms responsible for the direct action of metals on the structures of the nervous system is still insufficient [3,4]. The pathomechanism of the effect of metals on neurophysiological functions and the bioelectrical activity of the central nervous system (CNS) is not fully known. Clinical symptoms are non-specific and often poorly expressed. The most common manifestations of CNS damage include encephalopathy, cranial nerve palsy, cerebellar

Objectives

Methods

Results

Discussion

Conclusion