Investigation of Heavy Metals Pollution and Their Removal Methods: A Review

Abstract

The progress of the industry and the increase in the production of pollutants have caused the environment to be exposed to pollution. Among pollutants, heavy metals (HMs) cause irreparable hazards due to their accumulation and non-biodegradability. Contamination of water and soil with HMs causes them to accumulate in plants and animals, and finally, they enter the food chain and have irreparable effects on human health. The nature of HMs is toxic, so even trace amounts of them can cause problems. Many factors cause the release of heavy metals, such as improper waste disposal, sewage, agricultural fertilizers, pesticides, automobiles, coal mines, and thermal power plants. Therefore, the most important method is to properly manage the sources of pollution and then remove the HMs that have caused soil and water pollution. In this study, HMs pollution and their removal methods have been investigated. For this purpose, the contamination of heavy metals in water (river, fish, and shrimp), street dust, surface soil, vegetables, and vegetable oils were investigated. Also, some removal methods (phytoremediation, use of nanoparticles and polymers) and adsorbent materials (such as zeolites, clay minerals, and activated carbons) of HMs are investigated.