Mercury toxicity in human via cosmetics and associated health risks (Emphasizing on whitening creams) - Introduction

 1. INTRODUCTION

Heavy metal toxicity is a major global public health issue that has been highly neglected compared to other health issues. The term “heavy metals” refers to metals that have a relatively high density (more than 5g/cm3) which has the potential to accumulate through various routes to become toxic and cause adverse health effects in humans. A suggestion has been made by some scientists in recent times to replace the controversial term “heavy metals” with the phrase “potentially harmful elements”(Witkowska et al., 2021).

These are available naturally or industrially and are being used in many fields. Cadmium (Cd), Chromium (Cr), Lead (Pb), and Mercury (Hg) may be included in the list of heavy metals that are harmful to human health with high concern. World Health Organization (WHO) has included Cd, Pb, and Hg in the list of chemicals of public health concern (who. int), and this discussion is only built around Mercury.

Fig A: Chemicals of Major Public Health Concerns – World Health Organization (1 June 2020)

Mercury is a liquid heavy metal that naturally occurs in the earth’s crest (Wang & Fang, 2021). Mercury exists in elemental, inorganic, and organic forms (Bernhoft, 2012)(Aksoy et al., 2021). The heavy metal has been used for ages in the preparation of medicine (diuretic, antiseptic, skin ointment, laxative, and as a treatment of syphilis), poison(Broussard et al., 2002), fluorescent light bulbs, cosmetics, and medical instruments (Caza & Al-Rabadi, 2022). Further, in thermometer, battery, and barometer manufacturing, halide relay switches, high-intensity discharge lamps, and fungicides, mercury is used. During the practice of spiritist faiths such as Santeria, Esperitismo, and voodoo, mercury has been used ritualistically among Latino and African Caribbean populations. (Broussard et al., 2002)

Despite having a wide range of applications across many fields and industries, the toxicity of mercury is a threat to human health. All existing forms of mercury are toxic(Broussard et al., 2002) and that resulted in a decline in industrial usage (Aksoy et al., 2021).  Exposure to mercury will result in a wide range of adverse health conditions due to toxicity and will be discussed in the later part of this discussion.

There are major public health disasters that have been reported due to mercury toxicity in Minamata bay, Japan, and Iraq (Bernhoft, 2012). These disasters have resulted in severe public health consequences. Mercury being the third most toxic chemical has drawn attention and resulted in the emergence of the Minamata Convention on Mercury (MCM) in 2013. Over one hundred countries have ratified MCM to battle this hazard all over the world (Afzal et al., 2018a). United Nations Environment under MCM has approved many Minamata Initial Assessment (MIA) projects across the world.

Figure B: Chronic mercury poisoning and sources of exposure         

Although exposure to mercury is possible through various routes like air, gastrointestinal tract, or dermal absorption from many diverse sources, the discussion is focusing on mercury toxicity in humans by cosmetics products and the health risks associated with it. Picture B drawn from (Caza & Al-Rabadi, 2022)  shows various sources of mercury exposure and a few possible health risks.

#The remaining parts will be uploaded consecutively with relevant references.