Toxic effects due to exposure heavy metals and increased health risk assessment (leukemia).

Heavy metals (HM) are among the elements that are rare in nature and threaten human health, animals, and the environment. Fix sources including (power plants, industries, homes) and mobile sources include (cars and motorcycles) are the main sources production and emission of HM. It is important to understand the main information about sources of emission, chemical processes (reactions, oxidation, and leaching), and how they precipitate. The aim of this study was to evaluation an increased risk of leukemia due to exposure to HM. In this article narrative, the first literature search was performed with 580 articles according to different databases: Elsevier, PubMed, Web of science, Spring, and Google Scholar databases. 70 articles were included in the analysis process. Finally, 8 full-text articles were selected in this research. The search was restricted to English-language papers published between 2000 and 2021. In final stage literature, there is a notable health effect (carcinogenic) because of exposure to heavy metals. According to the results of this research natural procedures and human activities (industrial processes, car exhaust, and cigarette smoke) are the most important of ways that heavy metals can enter the natural cycle. Air, food, soil, water, and groundwater are the main sources of heavy metals that can cause severe disorders in the human body. After entering the body through ingestion heavy metals produce stable bio-toxic compounds. These compounds by disrupting biological processes, interrupt the body's functions and cause various cancers in the human body. The results of this study can help to politicians for make comprehensive decisions to solve the problem and increase public awareness of the use of protective equipment.