Health Issues and Heavy Metals

Special Article - Heavy Metal Pollution

Austin J Environ Toxicol. 2017; 3(1): 1018.

Health Issues and Heavy Metals

Bhargava P1, Gupta N1, Vats S1 and Goel R2*

1Institute of Biosciences and Technology, Sri Ramswaroop Memorial University, India

2Department of Microbiology, G.B.Pant University of Agriculture and Technology, India

*Corresponding author: Goel Reeta, Department of Microbiology, G.B.Pant University of Agriculture and Technology, India

Received: August 02, 2017; Accepted: October 09, 2017; Published: October 16, 2017


Several health hazards have been associated with heavy metals for a long time. The risk is continuously increasing though emissions have declined in developed countries over the last century. It is because of the fact that the heavy metals are very difficult to recycle and the new therapies used for treatment of many neurogenetic disorders involve the intake of heavy metals. Cigarette smoking whether active or passive is also an important source of exposure to these metals. The process of biomagnifications has given fatal diseases to many people where the pregnant women and the foetus are at maximum risk. They sometimes act as a pseudo element of the body while at certain times they interfere with the basic metabolic processes. Various measures have been taken by different countries at policy level and public level to control, prevent and treat metal toxicity occurring at various levels, such as occupational exposure, accidents and environmental factors. However, metal toxicity depends upon the amount of absorbed dose, the route of exposure and duration of exposure, i.e. acute or chronic. This can lead to various disorders and can also result in excessive damage due to oxidative stress induced by free radical formation. This review gives details about some heavy metals and their toxicity mechanisms, along with their health effects.


One of the most negative consequences of the industrialization is the proliferation of the heavy metal pollution in air, water and land. Rising pollution, changing life style, and disturbed circadian cycles has led to rise in health-related disorders. There are phenotypic and genotypic factors which affects the health of an individual. And environment is the most important phenotypic effect affecting genotypes also. Environmental exposure of air, water and land contaminated with heavy metals like Lead (Pb), Cadmium (Cd), Arsenic (As), Mercury (Hg), Manganese (Mn), Nickel (Ni), Zinc (Zn), Chromium (Cr), Cobalt (Co), Copper (Cu), Molybdenum (Mo), Antinomy (Sb), etc have posed serious threat to the well being of humans. According to the U.S geological survey 1133, 1995 heavy metals were classified into various categories like nontoxic, low toxic moderate and highly toxic. Below is the (Table 1) depicting the classification of heavy metals based on their toxicity? Heavy metals are essential only as trace elements for normal metabolic functioning but, at higher concentration, heavy metals are toxic [1]. Once the heavy metals are consumed they persist for indefinite time and cannot be biodegraded. They keep on accumulating and at higher concentration they form complex compounds within the cells and tissues, leading to diseases. There are number of diseases outcome of heavy metals exposure. But it is also important to keep in mind that diagnosis is not always the disease [2].

Heavy metals and immune system

One of the important aspect related to the immune system is that exposure to heavy metals can suppress the immune system and increase production of toxic products in the body [3].

Heavy metals are stable, xenobiotic and are non-biodegradable, once taken they persist in the body, tissues and cells. Exposure to the toxic environment is done by inhalation of air contaminated with metal dusts, fumes and small particle generated by combustions, intake of contaminated food, eating at contaminated site, eating without washing hands. On intake, the heavy metals become integral part of some body parts like bones. Kidney, liver, brain and accumulate with many years half-life [4]. Toxic metals are thrown out of the body by kidney and gastrointestinal tract. There are some proteins which play an important role in their detoxification. Metallothionein (MT) a cysteine rich protein, MW ranging from 500-14000 Da, exist in ten closely related expressed proteins form in human body (Table 2 and Figure 1).