Uncommon Heavy Metals, Metalloids and Their Plant Toxicity: A Review

Abstract

Heavy metals represent a group of dangerous pollutants, to which is paid close attention. Many heavy metals are essential as important constituents of pig-Abstract Heavy metals represent a group of dangerous pollutants, to which is paid close attention. Many heavy metals are essential as important constituents of pig-ments and enzymes—mainly zinc, nickel, and copper. However, all metals, espe- cially cadmium, lead, mercury, and copper, are toxic in high concentrations because ments and enzymes—mainly zinc, nickel, and copper. However, all metals, espe- cially cadmium, lead, mercury, and copper, are toxic in high concentrations because they disrupt enzyme functions, replacing essential metals in pigments or producing cially cadmium, lead, mercury, and copper, are toxic in high concentrations because they disrupt enzyme functions, replacing essential metals in pigments or producing reactive oxygen species. The toxicity of less common heavy metals and metalloids, such as thallium, arsenic, chromium, antimony, selenium, and bismuth has been reactive oxygen species. The toxicity of less common heavy metals and metalloids, such as thallium, arsenic, chromium, antimony, selenium, and bismuth has been investigated. Here we review the phytotoxicity of thallium, chromium, antimony, such as thallium, arsenic, chromium, antimony, selenium, and bismuth has been investigated. Here we review the phytotoxicity of thallium, chromium, antimony, selenium, bismuth; and other rare heavy metals and metalloids such as tellurium, germanium, gallium, scandium, gold, platinum group metals (palladium, platinum, selenium, bismuth; and other rare heavy metals and metalloids such as tellurium, germanium, gallium, scandium, gold, platinum group metals (palladium, platinum, and rhodium), technetium, tungsten, uranium, thorium; and rare earth elements such germanium, gallium, scandium, gold, platinum group metals (palladium, platinum, and rhodium), technetium, tungsten, uranium, thorium; and rare earth elements such as yttrium, lanthanum, and 14 lanthanides—cerium, dysprosium, erbium, europium, gadolinium, holmium, lutetium, neodymium, promethium, praseodymium, samar-as yttrium, lanthanum, and 14 lanthanides—cerium, dysprosium, erbium, europium, gadolinium, holmium, lutetium, neodymium, promethium, praseodymium, samar- ium, terbium, thulium, and ytterbium. gadolinium, holmium, lutetium, neodymium, promethium, praseodymium, samar- ium, terbium, thulium, and ytterbium.