Effects of minimal arsenic, lead, and cadmium exposure on biological pathways in Brazilian informal workers welding fashion jewelry

Introduction

This study complements previous research about informal workers occupational exposure by investigating the whole blood transcriptome of women engaged in informal home-based jewelry production in the city of Limeira, Sao Paulo, Brazil, focusing on associations between gene expression and arsenic (As), cadmium (Cd), and lead (Pb) concentrations in blood, as well as on identifying transcriptome profiles linked to self-reported health outcomes.

Methods

Participants were divided into two groups: an exposed group comprising informal workers engaged in domestic jewelry welding activities (n = 22) and a control group composed of neighbors without occupational exposures (n = 19). Linear regression modeling assessed the association between the blood concentration of toxic elements, gene expression, and reported health outcomes. Pathway analysis was performed using ConsensusPathDB.

Results

269 differentially expressed genes (DEGs) associated with As exposure and 43 with Cd exposure were found in this study, revealing significant health impacts on these workers. DEGs were also significantly associated with respiratory illness (bronchitis and asthma), neurological manifestations (sleep problems, migraines, or frequent headaches), shortness of breath, blood glucose, cholesterol, and triglyceride levels. Pathway analysis indicates genes related to inflammatory processes, alterations in intestinal permeability, and neurological outcomes.

Conclusion

The results shed light on the transcriptomic changes in this occupational context and contribute to a better understanding of the challenges faced by informal workers. Even with low doses of toxic elements in the blood, it was possible to observe differences in gene expression linked to self-reported outcomes. Additional studies should clarify the biological processes associated with toxic elements exposure.