Potential health risk of heavy metals in the leather manufacturing industries in Sialkot, Pakistan

Muhammad Junaid,Yu-Mei Tang,Riffat Naseem Malik,De-Sheng Pei,Muhammad Zaffar Hashmi

doi:10.1038/s41598-017-09075-7

Abstract

This is a systematical report on the potential health risk of heavy metals from the leather industries in Pakistan based on multiple biological matrices of the exposed workers and indoor dust samples. The adverse impacts of heavy metals on the oxidative enzyme and their risks to workers’ health were also explored. Our results indicated that the level of Cr in indoor industrial dust was more than twice, compared to the background household dust. Blood, urine and hair samples of exposed workers showed significantly high concentrations of heavy metals, compared to those in the control group. Superoxide dismutase (SOD) level in the blood samples expressed significant positive correlation with Cr and Ni. Total hazard quotients (HQs)/hazard index (HI) were >1, and Cr (VI) exhibited higher cancer risks than that of Cd in the exposed workers. In addition, the PCA-MLR analysis confirmed that the industrial sections; cutting, shivering/crusting, and stitching were the principal contributors of heavy metals in the biological entities of the workers. Taken together, our results highlighted the occupationally exposed groups would likely to experience the potential health risks due to excessive exposure to the heavy metals from the leather industries.

Highlights

Leather industry has substantial economic importance; it faces more and more criticism because of the toxic waste emissions as a result of leather tanning and processing
Chronic exposure to toxic metals can increase the generation of reactive oxygen species (ROS) in the body, which lead to the induction of oxidative stress and cause substantial damage to the cellular
The concentrations of heavy metals in the blood and urine samples of exposed worker and control group are presented in the Fig. 2

Summary

Introduction

Leather industry has substantial economic importance; it faces more and more criticism because of the toxic waste emissions as a result of leather tanning and processing. The dust emitted from the processing of the leather contains 0.1–4.5% of Cr(III), which can cause severe health hazards to the exposed workers[1, 2]. Occupational exposure to heavy metals other than Cr can cause enormous health impairments, such as asthma, back pains, bronchitis, chronic dermatitis, chromosomal abrasion, hypertension, hemoglobin changes, metabolic syndrome, DNA damage and even cancer[13,14,15,16]. Cells naturally activate the immune system in the form of different antioxidants such as superoxide dismutase (SOD), glutathione (GSH) and reduced glutathione (rGSH), etc These antioxidants try to balance the oxidative stress and nullify the toxic impacts of heavy metals through synergistic actions[19, 20]. The indoor dust has been proved an excellent marker of indoor heavy metal exposure in the industrial and urban settings[23, 24]

Methods

Results

Discussion

Conclusion