Toxicological Evaluations of Rare Earths and Their Health Impacts to Workers: A Literature Review

Abstract

In concert with the development of new materials in the last decade, the need for toxicological studies of these materials has been increasing. These new materials include a group of rare earths (RE). The use of RE nanotechnology is being considered in some green applications, to increase their efficiency by using nano-sized RE compounds, and therefore hazard evaluation and risk assessment are highly recommended. This review was conducted through an extensive contemplation of the literatures in toxicology with in vitro and in vivo studies. Major aspects reviewed were the toxicological evaluations of these elements and metallic compounds at the molecular and cellular level, animal and human epidemiological studies and environmental and occupational health impacts on workers. We also discuss the future prospect of industries with appliances using RE together with the significance of preventive efforts for workers' health. To establish a safe and healthy working environment for RE industries, the use of biomarkers is increasing to provide sustainable measure, due to demand for information about the health risks from unfavorable exposures. Given the recent toxicological results on the exposure of cells, animals and workers to RE compounds, it is important to review the toxicological studies to improve the current understanding of the RE compounds in the field of occupational health. This will help to establish a sustainable, safe and healthy working environment for RE industries.

Using Local Moran's I to identify contamination hotspots of rare earth elements in urban soils of London

“…For instance, REEs can accumulate in human brains via blood circulation, which may induce neurotoxic effects (Hollriegl et al, 2010 andRim et al, 2013), cause lung diseases when inhaling dust and metal fumes (USEPA, 2012), and afflict patients with diseases such as leukemia, cancer, and birth defects of children (Ismail et al, 2001;Liang et al, 2014;Rim et al, 2013). In addition, high exposure levels of REEs may lead to liver function decline (Wei et al 2013).…”

Rare Earth Elements in the Soil Environment

“…The main spots for accumulation are the bones, liver, and lungs [156,159,160]. Some damage can be mentioned, such as cardiac, hepatic, hematological, and renal problems, besides effects in the gastrointestinal tract, in bones, in the central nervous system, and in the pulmonary and cytogenetic systems [79,156,[159][160][161][162]. Despite this, the current information is not enough to determine the safe levels of exposure in humans [160], with values found being described as temporary [163].…”

“…Several studies involving effects of REE in experimental animals have reported an accumulation of these elements with time. The main spots for accumulation are the bones, liver, and lungs [156,159,160]. Some damage can be mentioned, such as cardiac, hepatic, hematological, and renal problems, besides effects in the gastrointestinal tract, in bones, in the central nervous system, and in the pulmonary and cytogenetic systems [79,156,[159][160][161][162].…”

Influence of Dy3+ and Tb3+ doping on 13C dynamic nuclear polarization

“…38 While the use of these lanthanides may lead to significant polarization gains, the free ion form of these lanthanides may lead to greater toxicity of the DNP sample, which must be considered prior to in vivo biomedical application. 39 One method used to combat the toxicity of rare earth metals is to encage these lanthanide ions with a chelating agent, thus rendering them relatively inert in the body. 40 Among the more prominent ligands used in gadolinium contrast agents are DTPA, 40,41 HP-DO3A, 42,43 and DOTA.…”