Mercury is widely used in medicine, agriculture, and industry. Meanwhile, according to the World Health Organization, it has been ranked as one of the ten most hazardous substances in the world, with the Agency for Toxic Substances and Disease Registry ranking it third. It has no known positive functionality in the human body, and even at low concentrations, it can have harmful long-term health effects, seriously affecting the healthcare system as well as posing a serious public health threat. This review focuses on the health effects of mercury and its major sources in the environment. We highlight its major toxic role in almost every possible aspect. Mercury and its forms, even in the smallest doses, cause numerous disorders to the body, including to the nervous system, the respiratory system, and the cardiovascular system. It can cause disorders such as various cancers
endothelial dysfunction
gastric and vascular disorders
liver, kidney, and brain damage
hormonal imbalances, miscarriages, and reproductive disorders
skin lesions
vision damage
and even death. The fact of such widespread use as well as its toxicity to the human body prompts further and in-depth research in populations of both low and moderate exposure. The constant controlling and monitoring of mercury use is a serious public health problem, requiring urgent attention and attentiveness from the governments of all countries and, in the long run, a rapid and concerted response. Thus, it is important to analyze in depth the impact of this highly toxic metal on the human body and to prepare the most precisely targeted public health interventions among all decision- and policy-makers.