Toxic Heavy Metals Distributed In Environment Through Processes Such As Volcanic Eruptions, Spring Waters, Erosion, & Bacterial Activity.

Metals Are Natural Constituents That Exist In The Ecosystem. They Are Substances With High Electrical Conductivity Which Voluntarily Lose Their Electrons To Form Cations. Metals are found all over the earth including the atmosphere, earth crust, water bodies, and can also accumulate in biological organisms including plants and animals. Among the 35 natural existing metals, 23 possess high specific density above 5 g/cm3 with atomic weight greater than 40.04 and are generally termed heavy metals.

Theses metals generally termed heavy metals include: antimony, tellurium, bismuth, tin, thallium, gold, arsenic, cerium, gallium, cadmium, chromium, cobalt, copper, iron, lead, mercury, manganese, nickel, platinum, silver, uranium, vanadium, and zinc. These categories of metals termed heavy metals have not only been known for their high density but most importantly for their adverse effects to the ecosystem and living organisms. Some of these heavy metals such as cobalt, chromium, copper, magnesium, iron, molybdenum, manganese, selenium, nickel and zinc are essential nutrients that are required for various physiological and biochemical functions in the body and may result to deficiency diseases or syndromes if not in adequate amounts but in large doses they may cause acute or chronic toxicities.

These heavy metals are distributed in the environment through several natural processes such as volcanic eruptions, spring waters, erosion, and bacterial activity, and through anthropogenic activities which include fossil fuel combustion, industrial processes, agricultural activities as well as feeding. These heavy metals do bio-accumulate in living organisms and the human body through various processes causing adverse effects. Some heavy metals are known to have carcinogenic effect.

Several signaling proteins or cellular regulatory proteins that participate in apoptosis, cell cycle regulation, DNA repair, DNA methylation, cell growth and differentiation are targets of heavy metals. Thus, heavy metals may induce carcinogenic effect by targeting a number of these proteins. More so, the carcinogenic effects of certain heavy metals have been related to the activation of redox-sensitive transcription factors such as AP-1, NF-κB and p53 through the recycling of electrons by antioxidant network. These transcription factors control the expression of protective genes that induce apoptosis, arrest the proliferation of damaged cells, repair damaged DNA and power the immune system.

In the human body, these heavy metals are transported and compartmentalized into body cells and tissues binding to proteins, nucleic acids destroying these macromolecules and disrupting their cellular functions. As such, heavy metal toxicity can have several consequences in the human body. It can affect the central nervous function leading to mental disorder, damage the blood constituents and may damage the lungs, liver, kidneys and other vital organs promoting several disease conditions.

Also, long term accumulation of heavy metals in the body may result in slowing the progression of physical, muscular and neurological degenerative processes that mimic certain diseases such as Parkinson’s disease and Alzheimer’s disease. More so, repeated long-term contact with some heavy metals or their compounds may even damage nucleic acids, cause mutation, mimic hormones thereby disrupting the endocrine and reproductive system and eventually lead to cancer. This article was also compiled with the help of my immediate boss SP Waqar Shoaib Qureshi, currently posted at capital city police officer office Lahore as Sr. superintendent of Police administration.