Toxicity, mechanism and health effects of some heavy metals

Abstract

Heavy metal toxicity has proven to be a major threat and there are several health risks associated with it. The toxic effects of these metals, even though they do not have any biological role, remain present in some or the other form harmful for the human body and its proper functioning. They sometimes act as a pseudo element of the body while at certain times they may even interfere with metabolic processes. Few metals, such as aluminium, can be removed through elimination activities, while some metals get accumulated in the body and food chain, exhibiting a chronic nature. Various public health measures have been undertaken to control, prevent and treat metal toxicity occurring at various levels, such as occupational exposure, accidents and environmental factors. Metal toxicity depends upon the 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.

Review: Nutritional ecology of heavy metals

“…At higher doses, heavy metals can cause irreversible brain damage (Jaishankar et al, 2014). It is also very important to consider that children receive higher doses of metals from food than adults, as they consume more food in relation to their BW (Thirulogachandar et al, 2014).…”

Heavy metals and their general toxicity for plants

“…Besides the fact that antioxidant systems composed of antioxidants and specific enzymes, are being studied extensively, still some important intrinsic mechanisms and characteristics about this network remain unknown (47)(48)(49)(50). The stress that heavy metals have on antioxidant system and plant cell is presented on Fig.…”

Non Typical Risk Factors in Atherosclerosis and Coronary Disease. It Is Time to Open the Box and Look Outside

“…Heavy metal toxicity can lower energy levels and damage the functioning of the brain, lungs, heart, blood vessels, kidney, liver, blood composition and other important organs. Repeated long-term exposure of some metals and their compounds may even cause cancer [5].…”

“…In vivo and in vitro studies have shown that chronic lead exposure causes HTN and cardiovascular disease by promoting oxidative stress, limiting nitric oxide availability, impairing nitric oxide signalling, augmenting adrenergic activity, increasing endothelin production, altering the renin-angiotensin system, raising vasoconstrictor prostaglandins, lowering vasodilator prostaglandins, promoting inflammation, disturbing vascular smooth muscle Ca(2+) signalling, diminishing endotheliumdependent vasorelaxation, and modifying the vascular response to vasoactive agonists [5]. Moreover, lead has been shown to cause endothelial injury, impede endothelial repair, inhibit angiogenesis, reduce endothelial cell growth, suppress proteoglycan production, stimulate vascular smooth muscle cell proliferation and phenotypic transformation, reduce tissue plasminogen activator, and raise plasminogen activator inhibitor-1 production [6][7][8][9].…”