**3. Mercury in medicine**

Mercury is used in dental amalgam fillings to increase its strength and longevity; yet it plays a negative role in increasing human toxicity [18, 19]. Although this type of pollution is going down as the number of medical waste incinerators is reduced, the health community is concerned about patients and other vulnerable groups who are exposed to in healthcare products [20]. Thiomersal is an organic compound used as a preservative in vaccines, and Merbromin (Mercurochrome) is a topical antiseptic used for minor cuts and scrapes and is still in use in some countries [21]. Mercury compounds are found in some over-the-counter drugs, including topical antiseptics, stimulant laxatives, diaper-rash ointment, eye drops, and nasal sprays [22]. The skin-whitening cosmetic products can also be a source of Hg pollution [23]. Even some traditional medicines in China as Siddha and Ayurveda may contain mercury that causes chronic poisoning [24]. Overall, air, water, food, cosmetics, and even vaccines are potential sources of human pollution with Hg [25]. Mercury and most of its compounds are extremely toxic and must be handled with care.
