Assessment of Heavy Metal Contamination in the Industrial Region of Kanpur’s Tannery Sector and Its Removal from Water Using Biochar

Abstract

The leather tanning industry in Kanpur, India, has grown exponentially over the years, becoming one of the largest producers of leather in the country. However, this rapid industrial growth has resulted in significant environmental contamination, primarily due to heavy metals. Key pollutants like chromium, lead, cadmium, nickel, and copper are frequently found in the effluents discharged from the tanneries. This paper investigates the causes, mechanisms, and consequences of heavy metal contamination in the industrial areas of Kanpur, focusing particularly on the tannery industry in Jajmau. It assesses the effects on human health, ecosystems, and the economy while evaluating current pollution control measures and suggesting solutions to mitigate the ongoing crisis.

Introduction

Kanpur, known as the "Leather City of the World," hosts one of India’s largest tannery industries, significantly contributing to the local and national economy through leather manufacturing and exports. However, the industry has caused severe environmental pollution, especially heavy metal contamination—mainly chromium, cadmium, lead, nickel, and copper—due to untreated effluent discharge.

The tanning process uses toxic chemicals, particularly chromium salts, which lead to the release of hazardous heavy metals into the Ganges River, soil, air, and food chains. This contamination harms ecosystems, reduces agricultural productivity, and poses serious public health risks, including respiratory diseases, cancer, neurological disorders, and kidney damage—affecting tannery workers and local residents.

Heavy metals spread through multiple pathways: water pollution from direct effluent discharge, soil contamination from improper waste disposal, air pollution from chemical fumes, and biomagnification through the food chain. The persistent contamination disrupts aquatic life, agriculture, and human health.

Mitigation strategies include adopting cleaner tanning technologies (e.g., vegetable tanning), advanced wastewater treatment, and bioremediation/phytoremediation methods to reduce pollution. Improved waste management and stricter environmental controls are also necessary.

Removing heavy metal contamination would restore the Ganges and soil health, improve agricultural yields, protect biodiversity, and reduce health risks, leading to economic benefits such as safer food supplies and enhanced trade opportunities for sustainably produced leather goods.

Conclusion

The heavy metal contamination caused by Kanpur’s tannery industry is a serious environmental and public health concern. While economic factors drive the industry’s growth, the environmental damage it causes cannot be ignored. The introduction of cleaner technologies, improved waste management practices, and better enforcement of pollution control regulations will be essential in mitigating the harmful effects of the tannery industry. Immediate action is needed to safeguard the environment, public health, and the livelihoods of local communities. The tannery industry can significantly reduce its environmental footprint by adopting cleaner production technologies, such as chrome-free tanning methods and closed-loop water systems, which minimize waste and heavy metal discharge. Transitioning to eco-friendly leather processing techniques like vegetable tanning and the use of biodegradable chemicals helps reduce reliance on harmful substances such as chromium salts, while also catering to the growing global demand for sustainable products. Furthermore, embracing waste-to-resource models within a circular economy framework allows for the recycling of tannery waste—such as sludge and effluents—into non-toxic, value-added products, including treated water for agriculture or biodegradable materials for other industries, thereby promoting both ecological responsibility and economic efficiency.

References

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Copyright

Copyright © 2025 Anaya Tripathi, Jaya Pandey, Richa Khare, Smriti Kahre. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.