Toxic Metal Pollution in Pakistan and Its Possible Risks to Public Health

Abstract

Environmental pollution has increased many folds in recent years and in some places has reached levels that are toxic to living things. Among pollutant types, toxic heavy metals and metalloids are among the chemicals that pose the highest threat to biological systems (Jjemba 2004). Unlike organic pollutants, which are biodegradable, heavy metals are not degraded into less hazardous end products (Gupta et al. 2001). Low concentrations of some heavy metals are essential for life, but some of them like Hg, As, Pb and Cd are biologically non-essential and very toxic to living organisms. Even the essential metals may become toxic if they are present at a concentration above the permissible level (Puttaiah and Kiran 2008). For example, exposure to Zn and Fe oxides produce gastric disorder and vomiting, irritation of the skin and mucous membranes. Intake of Ni, Cr, Pb, Cd and Cu causes heart problems, leukemia and cancer, while Co and Mg can cause anemia and hypertension (Drasch et al. 2006). Similarly, various studies indicated that overexposure to heavy metals in air can cause cardiovascular disorders (Miller et al. 2007; Schwartz 2001), asthma (Wiwatanadate and Liwsrisakun 2011), bronchitis/emphysema (Pope 2000), and other respiratory diseases (Dominici et al. 2006).

Clinical and Experimental Evidences of Hydrogen Sulfide Involvement in Lead-Induced Hypertension

“…We observed that patients intoxicated with Pb presented SBP similar to control patients. However, we detected an increase in diastolic and mean blood pressure in Pb-intoxicated patients, which is in accordance with previous reports in literature showing increases in blood pressure following Pb-intoxication in humans [ 8 , 51 – 55 ]. As H 2 S has been shown to have several actions in cardiovascular system, we investigated the levels of H 2 S in plasma from patients and found decreased plasmatic H 2 S levels in patients from Pb-intoxicated group.…”

Heavy metal content and health risk assessment of commonly patronized herbal medicinal preparations from the Kumasi metropolis of Ghana

“…This indicates that long-term exposure to HPF poses a health risk due to overexposure to copper. Copper is a microelement, but overexposure to this essential mineral has been reported to predispose the consumer to gastrointestinal mucosal ulcerations and bleeding, hepatic necrosis, coma, cardiotoxicity, hypotension [44], leukaemia and cancer [45]. Cd and Hg contents, on the other hand, were well below the MRL limits for all the 6 HPs.…”

Content of chemical elements in the liver of cattle with fasciolosis and dicrocoeliosis

“…Забруднення навколишнього природного середовища важкими металами стало глобальною проблемою. До головних факторів, що спричинили загрозливий стан довкілля, відносять застарілу технологію виробництва у промисловості, несучасне обладнання, низький рівень упровадження ресурсо-та енергозаощаджувальних, екологічно чистих технологій; високий рівень концентрації промислових об'єктів; відсутність належних природоохоронних систем; низький рівень експлуатації існуючих природоохоронних об'єктів; відсутність належного правового та економічного механізмів регулювання; прогресуючу урбанізацію населення, розростання гігантських мегаполісів, відсутність належного контролю за охороною довкілля, виверження вулканів (Davydova, 2005;Shakir et al, 2017).…”