From the Occupational and Environmental Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt.

ORCID ID: https://orcid.org/0000-0003-3698-9343.

ORCID ID: https://orcid.org/0000-0003-1798-6331.

Scopus Author ID: 57208981046

Funding source: None.

Conflict of Interest: None declared.

Patient consent: A written informed consent for sharing in the study was voluntarily obtained from each individual after proper explanation of the objectives of the current study.

Ethics approval: The study was approved by the Ethical Committee of the Occupational and Environmental Medicine Department, Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt (122019). Approval was taken from the Chief Executive Officer (CEO) of the studied smelter.

Laboratory investigations: All laboratory investigations were performed in the laboratory of the Medical Biochemistry Department, Faculty of Medicine, Cairo University (Cairo, Egypt).

Address correspondence to: Basma Hussein Mourad, MD, Lecturer of Occupational and Environmental Medicine, Faculty of Medicine, Cairo University, 124 El-Baher Al-Aazam St, Giza, Egypt ([email protected]; [email protected]; [email protected]).