Nickel in the environment

Abstract

The importance of nickel (Ni) in the environment is an issue that is gaining broader recognition. While nickel is an element essential for plants, it is also a heavy metal. Nickel is a component of nine metalloenzymes, including urease, which participates in urea hydrolysis. It also helps some plants to protect themselves against pathogens and herbivorous insects. There are many sources of Ni in the environment, which can be a problem because at higher concentrations this element is toxic to plants and other living organisms. Therefore, standards have been defined for the Ni content in air, water, soil and plants. Its content is monitored in the air. More and more frequently, attention is paid to this element as an allergen in humans. In the world, attempts have been made to phytoextract nickel from contaminated soils using nickelphilous plants, the so-called hyperaccumulators, and even to recover the metal from these plants by so-called phytomining. On the other hand, nickel-containing fertilizers are marketed and used in cases of nickel deficiency in plants. In industry, this element is primarily used for the production of steel and alloys. The most recent application of nickel is related to graphene, which was invented 10 years ago. Although nickel contamination does not occur in Poland, we cannot rule out this risk in the future. Thus, it is important to monitor the fate of nickel in the environment.

Molecular Biology-Based Analysis of the Interactive Effect of Nickel and Xanthates on Soil Bacterial Community Diversity and Structure

“…(2) Ni is a micronutrient, essentially involved in the metabolism of nitrogen, hydrogen, and other physiologically important elements. It is involved as a component or cofactor of several metalloenzymes, including acireductone dioxygenase, Ni-superoxide dismutase, methyl coenzyme M reductase, acetyl-CoA synthetase/decarboxylase, carbon monoxide dehydrogenase, and urease [6,51,53]. However, above a certain concentration limit, metals become deleterious, with different toxic mechanisms, including inhibiting cell division, enzyme activity and transcription, denaturing proteins, disrupting the cell membrane [8,54], etc., which result in the reduction of the diversity and size of a given exposed microbial population.…”

“…In addition to Ni mining and processing which are the main anthropogenic sources of Ni pollution, Ni is released into the environment from various anthropogenic sources, including transportation, oil combustion, and municipal and industrial wastes [6]. High Ni concentrations in the soil, more than 300 µg·g −1 soil [6][7][8], were reported in the soils from various sites, including rural areas of various countries. This is well above the permissible limit (less than 50 µg·g −1 soil for agricultural and non-industrialized soil and less than 100 µg·g −1 soil for commercial and industrial lands) [9].…”

“…The remaining part and the unrecovered metals are discharged into the environment, with no treatment in general [12]. In addition, the reported increase in Ni demand [6] and the gradual depletion of high-grade ore reserves leads to the exploitation of complex and low-grade ore [13]. This results in an increased amount of ore processed and xanthates consumed, by 2-3% per year [12], leading to higher Ni and xanthates released into the environment.…”

Effect of 24-epibrassinolide on ROS content, antioxidant system, lipid peroxidation and Ni uptake in Solanum nigrum L. under Ni stress

“…It is well documented that Ni is an essential micronutrient and plants cannot complete their life cycle without adequate levels of this metal (0.01 to 10 µg g -1 dry wt) (Gratão et al, 2008). Ni is a component of nine metalloenzymes and it is associated with nitrogen metabolism due to the presence of two Ni atoms in the active center of urease; it also promotes root nodule growth and hydrogenase activation (Harasim and Filipek, 2015;Khoshgoftarmanesh et al, 2014;Polacco et al, 2013). The fact that several enzyme activities depend on the presence of Ni may explain the benefit effects of this ion on plant growth and development (Dalton et al, 1985;Kazemi, 2012).…”

Microorganisms in Soils with High Nickel and Chromium Concentrations in Western Serbia

“…Although nickel is one of the essential trace metals for microorganisms, plants, and animals, constant exposure to excessive nickel in soils could strongly affect the inhabitant microorganisms, resulting in adverse effects on ecosystem functioning [20][21][22]. Chromium is not considered essential for microorganisms and plants, but it is a micronutrient in humans and can be highly toxic when accumulated [23].…”