Nickel, a transition element widely distributed in the environment, can derive from natural sources and anthropogenic activities. Despite its ubiquitous presence, its functional role as a trace element for animals and humans remains unclear. Environmental pollution from nickel is primarily due to industry, fuel use, and municipal and industrial waste. Contact with nickel can cause various health issues, including allergies, cardiovascular and kidney diseases, lung fibrosis, and cancer. The molecular mechanisms of nickel-induced toxicity are not fully understood, but mitochondrial dysfunctions and oxidative stress are thought to play a crucial role. Recent studies have also found that epigenetic alterations induced by nickel exposure can perturb the genome. This review aims to describe the chemical features of nickel in humans, its mechanisms of toxicity, and strategies for removing nickel from the environment, such as phytoremediation and phytomining. The article discusses the chemical properties, sources, and industrial uses of nickel, as well as its toxic effects on human health, including cancer, allergy, and teratogenicity. It also explores the epigenetic effects of nickel and its role in apoptosis. Finally, the potential of phytoremediation and phytomining in removing nickel from the environment is highlighted.Nickel, a transition element widely distributed in the environment, can derive from natural sources and anthropogenic activities. Despite its ubiquitous presence, its functional role as a trace element for animals and humans remains unclear. Environmental pollution from nickel is primarily due to industry, fuel use, and municipal and industrial waste. Contact with nickel can cause various health issues, including allergies, cardiovascular and kidney diseases, lung fibrosis, and cancer. The molecular mechanisms of nickel-induced toxicity are not fully understood, but mitochondrial dysfunctions and oxidative stress are thought to play a crucial role. Recent studies have also found that epigenetic alterations induced by nickel exposure can perturb the genome. This review aims to describe the chemical features of nickel in humans, its mechanisms of toxicity, and strategies for removing nickel from the environment, such as phytoremediation and phytomining. The article discusses the chemical properties, sources, and industrial uses of nickel, as well as its toxic effects on human health, including cancer, allergy, and teratogenicity. It also explores the epigenetic effects of nickel and its role in apoptosis. Finally, the potential of phytoremediation and phytomining in removing nickel from the environment is highlighted.