Journal of Occupational
Health and Epidemiology
Rafsanjan university Of medical sciences
Volume 13, Issue 4 (Autumn 2024)
J Occup Health Epidemiol 2024, 13(4): 269-279 |
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Yavar Z, Kargar-Shouroki F, Halvani G, Sefidkar R, Dehghani F. The Association between Blood Lead Level and Cognitive Functions among the Workers of a Lead Mine in Iran. J Occup Health Epidemiol 2024; 13 (4) :269-279
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Zahra Yavar1 
, Fatemeh Kargar-Shouroki *2 , Gholamhossein Halvani3 , Reyhane Sefidkar4 , Fahimeh Dehghani5
, Fatemeh Kargar-Shouroki *2 , Gholamhossein Halvani3 , Reyhane Sefidkar4 , Fahimeh Dehghani5
1- M.Sc. in Occupational Health Engineering, Industrial Diseases Research Center, Dept. of Occupational Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
2- Assistant Prof, Industrial Diseases Research Center, Dept. of Occupational Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. ,kargar_st@yahoo.com
3- Assistant Prof, Industrial Diseases Research Center, Dept. of Occupational Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
4- Assistant Prof, Center for Healthcare Data Modeling, Dept. of Biostatistics and Epidemiology, School of public health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
5- Assistant Prof, Dept. of Psychology and Educational Sciences, Yazd University, Yazd, Iran
2- Assistant Prof, Industrial Diseases Research Center, Dept. of Occupational Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. ,
3- Assistant Prof, Industrial Diseases Research Center, Dept. of Occupational Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
4- Assistant Prof, Center for Healthcare Data Modeling, Dept. of Biostatistics and Epidemiology, School of public health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
5- Assistant Prof, Dept. of Psychology and Educational Sciences, Yazd University, Yazd, Iran
Article history
Received: 2024/06/8
Accepted: 2024/09/10
ePublished: 2025/03/12
Accepted: 2024/09/10
ePublished: 2025/03/12
Subject:
Occupational Health
Abstract: (251 Views)
Background: Workers are exposed to lead in many industries and mines. The present study aimed to determine lead levels and cognitive functions among workers of a lead mine in Iran.
Materials and Methods: This cross-sectional study was conducted in Nain city in Isfahan Province, center of Iran, in 2022. The studied population consisted of 76 miners as the lead exposed group as well as a group of 76 office workers, working in the same mine, without any history of exposure to lead as the non-exposed group. Demographic information was collected using a questionnaire. The samples were analyzed using NIOSH techniques 8003 and 7082 to detect lead in the blood and breathing zone, respectively. The cognitive functions of the exposed and non-exposed groups were compared using the Wisconsin Card Sorting Test, digit span, Corsi block-tapping, Tower of London, and continuous performance tests.
Results: The mean lead levels in the breathing zone and blood were significantly higher in the exposed group (0.08 ± 0.06 mg/m3, 37.41 ± 10.28 µg/dl, respectively), compared to the non-exposed group (0.02 ± 0.01 mg/m3, 12.57 ± 4.27 µg/dl, respectively). The total scores for all cognitive tests in the exposed group were significantly worse than those in the non-exposed group. Even after controlling for age, work history, smoking, education, and body mass index, there were still significant correlations between blood lead levels and cognitive abilities (p<0.05).
Conclusion: According to the current study's findings, exposure to lead was associated with cognitive disorders.
Materials and Methods: This cross-sectional study was conducted in Nain city in Isfahan Province, center of Iran, in 2022. The studied population consisted of 76 miners as the lead exposed group as well as a group of 76 office workers, working in the same mine, without any history of exposure to lead as the non-exposed group. Demographic information was collected using a questionnaire. The samples were analyzed using NIOSH techniques 8003 and 7082 to detect lead in the blood and breathing zone, respectively. The cognitive functions of the exposed and non-exposed groups were compared using the Wisconsin Card Sorting Test, digit span, Corsi block-tapping, Tower of London, and continuous performance tests.
Results: The mean lead levels in the breathing zone and blood were significantly higher in the exposed group (0.08 ± 0.06 mg/m3, 37.41 ± 10.28 µg/dl, respectively), compared to the non-exposed group (0.02 ± 0.01 mg/m3, 12.57 ± 4.27 µg/dl, respectively). The total scores for all cognitive tests in the exposed group were significantly worse than those in the non-exposed group. Even after controlling for age, work history, smoking, education, and body mass index, there were still significant correlations between blood lead levels and cognitive abilities (p<0.05).
Conclusion: According to the current study's findings, exposure to lead was associated with cognitive disorders.
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