Assessment of Thyroid Function and Oxidative Stress State in Foundry Workers Exposed to Lead

March 18, 2025

  • Autoimmune Diseases
    Autoimmune Diseases

    Autoimmune disease is when the immune system mistakenly attacks the body's tissues, often linked to imbalances in the microbiome, which can disrupt immune regulation and contribute to disease development.

Last Updated: 2024

Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.

Karen Pendergrass

Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease—four years before the first published case study.

What was studied?
The study assessed thyroid function and oxidative stress in foundry workers occupationally exposed to lead (Pb) dust and fumes. It investigated the correlation between blood lead levels (BLL) and thyroid hormones, as well as markers of oxidative stress.

Who was studied?
The study involved 59 adult male foundry workers exposed to lead and a control group of 28 male subjects with no history of lead exposure or thyroid abnormalities.

 

What were the most important findings?

Foundry workers had significantly higher blood lead levels (16.5±1.74 µg/dl) compared to the control group (12.8±1.16 µg/dl).

The exposed group exhibited significantly increased levels of free triiodothyronine (FT3) and free thyroxine (FT4), and decreased levels of thyroid stimulating hormone (TSH).

Markers of oxidative stress showed a significant increase in malondialdehyde (MDA) and a significant decrease in glutathione (GSH) among exposed workers.

A significant positive correlation was found between BLL and duration of employment, while a negative correlation existed between BLL and both TSH and GSH levels.

Elevated thyroid hormones were observed in 32.76% of the occupationally exposed workers.

There was a significant positive relationship between GSH and TSH, and between MDA and FT3 and FT4 among exposed workers.

 

What are the greatest implications of this study?
The study suggests that occupational exposure to lead dust and fumes can stimulate thyroid function, resulting in increased thyroid hormone levels, which may contribute to an oxidative-antioxidant imbalance. This imbalance, indicated by increased MDA and decreased GSH levels, underscores the potential health risks associated with prolonged exposure to lead, highlighting the need for improved protective measures and monitoring in industrial settings.

Join the Roundtable

Contribute to published consensus reports, connect with top clinicians and researchers, and receive exclusive invitations to roundtable conferences.