scispace - formally typeset
Search or ask a question
Journal ArticleDOI

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

01 Mar 2013-Safety and health at work (Occupational Safety and Health Research Institute)-Vol. 4, Iss: 1, pp 12-26
TL;DR: It is important to review the toxicological studies to improve the current understanding of the RE compounds in the field of occupational health to establish a sustainable, safe and healthy working environment for RE industries.
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.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article, the authors summarized the occurrence of rare earth elements in the Earth's crust, their mineralogy, different types of deposits both on land and oceans from the standpoint of the new data with more examples from the Indian subcontinent.
Abstract: Rare earth elements (REE) include the lanthanide series elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) plus Sc and Y. Currently these metals have become very critical to several modern technologies ranging from cell phones and televisions to LED light bulbs and wind turbines. This article summarizes the occurrence of these metals in the Earth's crust, their mineralogy, different types of deposits both on land and oceans from the standpoint of the new data with more examples from the Indian subcontinent. In addition to their utility to understand the formation of the major Earth reservoirs, multi-faceted updates on the applications of REE in agriculture and medicine including new emerging ones are presented. Environmental hazards including human health issues due to REE mining and large-scale dumping of e-waste containing significant concentrations of REE are summarized. New strategies for the future supply of REE including recent developments in the extraction of REE from coal fired ash and recycling from e-waste are presented. Recent developments in individual REE separation technologies in both metallurgical and recycling operations have been highlighted. An outline of the analytical methods for their precise and accurate determinations required in all these studies, such as, X-ray fluorescence spectrometry (XRF), laser induced breakdown spectroscopy (LIBS), instrumental neutron activation analysis (INAA), inductively coupled plasma optical emission spectrometry (ICP-OES), glow discharge mass spectrometry (GD-MS), inductively coupled plasma mass spectrometry (including ICP-MS, ICP-TOF-MS, HR-ICP-MS with laser ablation as well as solution nebulization) and other instrumental techniques, in different types of materials are presented.

709 citations

Journal ArticleDOI
TL;DR: Several studies have demonstrated that REE, like a number of other xenobiotics, follow hormetic concentration-related trends, implying stimulatory or protective effects at low levels, then adverse effects at higher concentrations, and another major role for REE-associated effects should be focused on pH-dependent REE speciation and hence toxicity.

386 citations

Journal ArticleDOI
TL;DR: A conceptual framework and possible mitigation measures to minimize health risks are highlighted and future research is needed to better understand sources, environmental behaviour, ecotoxicology, and human epidemiology.

363 citations

Journal ArticleDOI
TL;DR: Gadolinium deposition in neural tissues after GBCA administration occurs in the absence of intracranial abnormalities that might affect the permeability of the blood-brain barrier, and these findings challenge current understanding of the biodistribution of these contrast agents and their safety.
Abstract: Our findings demonstrate that gadolinium deposition in neuronal tissues occurs even in the absence of intracranial abnormalities among patients exposed to multiple gadolinium-enhanced MR examinations.

253 citations

Journal ArticleDOI
TL;DR: The state of art provides a limited definition of the health effects in occupationally or environmentally REE-exposed human populations, and research priorities should be addressed to case-control or cohort studies of REE -exposed humans and to life-long animal experiments.

217 citations


Cites background from "Toxicological Evaluations of Rare E..."

  • ...Crystal polisher 1 Dendriform pulmon production of a number of REE-containing products, such as alloys, petroleum catalysts, permanent magnets, glass and ceramics (Du and Graedel, 2011; USEPA, 2012; Rim et al., 2013; Gambogi and Cordier, 2013) (Table 1)....

    [...]

References
More filters
Journal ArticleDOI
TL;DR: The data indicate that the nanoceria particles may be effective in inhibiting the progression of ROI-induced cell death, which is thought to be involved in macular degeneration, retinitis pigmentosa and other blinding diseases, as well as the ROi-induced death of other cell types in diabetes, Alzheimer's disease, atherosclerosis, stroke and so on.
Abstract: Photoreceptor cells are incessantly bombarded with photons of light, which, along with the cells' high rate of oxygen metabolism, continuously exposes them to elevated levels of toxic reactive oxygen intermediates (ROIs). Vacancy-engineered mixed-valence-state cerium oxide nanoparticles (nanoceria particles) scavenge ROIs. Our data show that nanoceria particles prevent increases in the intracellular concentrations of ROIs in primary cell cultures of rat retina and, in vivo, prevent loss of vision due to light-induced degeneration of photoreceptor cells. These data indicate that the nanoceria particles may be effective in inhibiting the progression of ROI-induced cell death, which is thought to be involved in macular degeneration, retinitis pigmentosa and other blinding diseases, as well as the ROI-induced death of other cell types in diabetes, Alzheimer's disease, atherosclerosis, stroke and so on. The use of nanoceria particles as a direct therapy for multiple diseases represents a novel strategy and suggests that they may represent a unique platform technology.

832 citations


"Toxicological Evaluations of Rare E..." refers background in this paper

  • ...These indicate that the nanoceria particles may be effective in inhibiting the progression of ROI-induced cell death [31]....

    [...]

Journal ArticleDOI
18 Dec 2009-Small
TL;DR: It is suggested that cerium oxide nanoparticles are well tolerated in mice and are incorporated into cellular tissues and therefore serve as a novel therapy for chronic inflammation.
Abstract: The valence and oxygen defect properties of cerium oxide nanoparticles (nanoceria) suggest that they may act as auto-regenerative free radical scavengers. Overproduction of the free radical nitric oxide (NO) by the enzyme inducible nitric oxide synthase (iNOS) has been implicated as a critical mediator of inflammation. NO is correlated with disease activity and contributes to tissue destruction. The ability of nanoceria to scavenge free radicals, or reactive oxygen species (ROS), and inhibit inflammatory mediator production in J774A.1 murine macrophages is investigated. Cells internalize nanoceria, the treatment is nontoxic, and oxidative stress and pro-inflammatory iNOS protein expression are abated with stimulation. In vivo studies show nanoceria deposition in mouse tissues with no pathogenicity. Taken together, it is suggested that cerium oxide nanoparticles are well tolerated in mice and are incorporated into cellular tissues. Furthermore, nanoceria may have the potential to reduce ROS production in states of inflammation and therefore serve as a novel therapy for chronic inflammation.

631 citations


"Toxicological Evaluations of Rare E..." refers background in this paper

  • ...In particular, CeO2 nanoparticles, considered one of the most interesting nanomaterials for their catalytic properties, show a promise for application in therapy [35]....

    [...]

  • ...It is suggested that CeO2 nanoparticles are well tolerated in mice, and are incorporated into cellular tissues [35]....

    [...]

Journal ArticleDOI
TL;DR: The cytotoxicity and oxidative stress caused by 20-nm cerium oxide (CeO2) nanoparticles in cultured human lung cancer cells was investigated and it was concluded that free radicals generated by exposure to 3.5 to 23.3 μg/ml CeO2 nanoparticles produce significant oxidative stress in the cells.
Abstract: With the fast development of nanotechnology, the nanomaterials start to cause people's attention for potential toxic effect. In this paper, the cytotoxicity and oxidative stress caused by 20-nm cerium oxide (CeO2) nanoparticles in cultured human lung cancer cells was investigated. The sulforhodamine B method was employed to assess cell viability after exposure to 3.5, 10.5, and 23.3 microg/ml of CeO2 nanoparticles for 24, 48, and 72 h. Cell viability decreased significantly as a function of nanoparticle dose and exposure time. Indicators of oxidative stress and cytotoxicity, including total reactive oxygen species, glutathione, malondialdehyde, alpha-tocopherol, and lactate dehydrogenase, were quantitatively assessed. It is concluded from the results that free radicals generated by exposure to 3.5 to 23.3 microg/ml CeO2 nanoparticles produce significant oxidative stress in the cells, as reflected by reduced glutathione and alpha-tocopherol levels; the toxic effects of CeO2 nanoparticles are dose dependent and time dependent; elevated oxidative stress increases the production of malondialdehyde and lactate dehydrogenase, which are indicators of lipid peroxidation and cell membrane damage, respectively.

492 citations


"Toxicological Evaluations of Rare E..." refers background in this paper

  • ...It is concluded that free radicals generated by exposure to CeO2 nanoparticles produce significant oxidative stress in the cells, as reflected by reduced glutathione (GSH) and alphatocopherol levels; the toxic effects of CeO2 nanoparticles are dose dependent and time dependent [32]....

    [...]

Journal ArticleDOI
TL;DR: Of the elements with high solubility in magnesium alloys, Gd and Dy seem to be more suitable than Y, and La and Ce showed the highest cytotoxicity of the analysed elements.

487 citations


"Toxicological Evaluations of Rare E..." refers background in this paper

  • ...The focus of alloy development for biomedical applications should include most defined alloy compositions, with well-known tissue-specific and systemic effects [30]....

    [...]

Journal ArticleDOI
TL;DR: There is an absolute critical need for integrated exposure and toxicological studies in order to accurately assess the environmental, ecological and health implications of nanotechnology enabled diesel fuel additives with existing as well as new engine designs and fuel formulations.
Abstract: Advances of nanoscale science have produced nanomaterials with unique physical and chemical properties at commercial levels which are now incorporated into over 1000 products. Nanoscale cerium (di) oxide (CeO(2)) has recently gained a wide range of applications which includes coatings, electronics, biomedical, energy and fuel additives. Many applications of engineered CeO(2) nanoparticles are dispersive in nature increasing the risk of exposure and interactions with a variety of environmental media with unknown health, safety and environmental implications. As evident from a risk assessment perspective, the health effects of CeO(2) nanoparticles are not only dependent on their intrinsic toxicity but also on the level of exposure to these novel materials. Although this may seem logical, numerous studies have assessed the health effects of nanoparticles without this simple but critical risk assessment perspective. This review extends previous exposure and toxicological assessments for CeO(2) particles by summarizing the current state of micro and nano-scale cerium exposure and health risks derived from epidemiology, air quality monitoring, fuel combustion and toxicological studies to serve as a contemporary comprehensive and integrated toxicological assessment. Based on the new information presented in this review there is an ongoing exposure to a large population to new diesel emissions generated using fuel additives containing CeO2 nanoparticles for which the environmental (air quality and climate change) and public health impacts of this new technology are not known. Therefore, there is an absolute critical need for integrated exposure and toxicological studies in order to accurately assess the environmental, ecological and health implications of nanotechnology enabled diesel fuel additives with existing as well as new engine designs and fuel formulations.

339 citations


"Toxicological Evaluations of Rare E..." refers background in this paper

  • ...Therefore, there is an absolutely critical need to investigate integrated exposure and to conduct toxicological studies, in order to accurately assess the environmental, ecological and health implications of nano-RE [19]....

    [...]