Chromium exists in two main forms, trivalent chromium [Cr(III)] and hexavalent chromium [Cr(VI)]. Cr(III) is essential for balancing blood sugar in humans but Cr(VI) is carcinogenic and contaminates groundwater. Chromium enters the environment and causes pollution through various industrial applications like steel manufacturing, electroplating, and chemical production. Exposure to chromium through industrial practices can cause health issues like lung cancer, skin allergies, and damage to organs. Lack of enforcement of environmental regulations has led to widespread chromium contamination globally, impacting millions of people, especially in South Asia where 75% of high-risk sites exist and groundwater in places like Kanpur, India has been contaminated

1. I. Introduction
Chromium is a hard metal and heavily used in “stainless steel and noniron alloy
production for plating metals, development of pigments, leather processing, and production of
catalysts, surface treatments, and in refractories” (Jacobs & Testa, 2004). Chromium is primarily
found in two common oxidation states: trivalent chromium [Cr(III)] and hexavalent chromium
[Cr(VI)]. Cr(III) has an essential role in balancing blood sugar in the human body (Jacobs &
Testa, 2004). Increments in Cr(III) are produced “due to leather, textile, and steel
manufacturing” (Sneddon, 2012). Cr(VI) is a carcinogen and a groundwater contaminant (Jacobs
& Testa, 2004). Cr(VI) enters the environment through similar industrial applications; “but also
due to electro-painting and chemical manufacturing” (Sneddon, 2012). Groundwater pollution
“may occur due to seepage from chromate mines or improper disposal of mining tools and
supplies, or improper disposal of industrial manufacturing equipment” (Sneddon, 2012).
Cr(VI) requires electrons to reach a stable oxidation state [Cr(III)], the production of
“free radicals, superoxide anions, and hydroxyl free radicals” eventuates as Cr(VI) enters “into
the cells in the form of chromate which may cause cellular damage” (Zhang et al, 2014). The
exposure of chromium from the industrial practices is accountable for several pathological
changes on human beings such as “pulmonary carcinomas, allergic dermatitis, and tissue
damage, especially to the central nervous and reproductive systems” (Dlugosz et al, 2011).
The application of chromium without proper follow-up treatment and the lack of
appropriate enforcement of the environmental regulations have resulted in various
contaminations in natural resources. Approximately 13 million people in the world are impacted
by chromium pollution and 75% of the Cr risk sites have been identified in South Asia
(Blacksmith Institute’s Report, 2012). For example, it was reported that the groundwater in
Kanpur, India, has been contaminated with wastes disposed by leather tanneries (Blacksmith
Institute, 2015). South Asia has been considered as the most impacted region by the chromium