Alkaline earth silicate wools – A new generation of high temperature insulation

Brown, R. C.; Harrison, Paul

doi:10.1016/j.yrtph.2012.08.020

Cited by 25 publications

(17 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The toxicity of inhaled fibres is described by the so called '3Ds' paradigm which recognises that the most important parameters are dose, dimension (fibre length and diameter, which determine both respirability and pathogenicity in the lung) and durability (or, more properly, biopersistence) (Bernstein et al, 2001a;Bernstein et al, 2001b;Brown & Harrison, 2012;.…”

Section: Introductionmentioning

confidence: 99%

A comparison of the results from intra-pleural and intra-peritoneal studies with those from inhalation and intratracheal tests for the assessment of pulmonary responses to inhalable dusts and fibres

Drummond

Bevan²,

Harrison³

2016

Regulatory Toxicology and Pharmacology

View full text Add to dashboard Cite

The aim of this paper is to compare results from inhalation studies with those from intraperitoneal and intrapleural tests, where available, for a number of fibrous and particulate test materials. The objective is to determine how well intraperitoneal/intrapleural studies predict the pathological responses observed in more standard in vivo studies of pulmonary toxicity, with a particular focus on carcinogenicity. Published toxicity data was obtained for a number of materials including asbestos, wollastonite, MMVFs (including glass fibres, stone wools and RCF), silicon carbide whiskers, potassium octatitanate, quartz, kevlar, polypropylene and titanium dioxide. For some of the fibrous material reviewed, there is conformity between the results of intraperitoneal and inhalation tests such that they are either consistently positive or consistently negative. For the remaining fibrous materials reviewed, intraperitoneal and inhalation tests give different results, with positive results in the intraperitoneal test not being reflected by positive inhalation results. It is suggested that the intraperitoneal test can be used to exonerate a dust or fibre (because if negative in the intraperitoneal test it is extremely unlikely to be positive in either inhalation or intratracheal tests) but should not be used to positively determine that a dust or fibre is carcinogenic by inhalation. We would argue against the use of intraperitoneal tests for human health risk assessment except perhaps for the purpose of exoneration of a material from classification as a carcinogen.

show abstract

Section: Introductionmentioning

confidence: 99%

A comparison of the results from intra-pleural and intra-peritoneal studies with those from inhalation and intratracheal tests for the assessment of pulmonary responses to inhalable dusts and fibres

Drummond

Bevan²,

Harrison³

2016

Regulatory Toxicology and Pharmacology

View full text Add to dashboard Cite

show abstract

“…AES wools are less biopersistent fibers capable of substituting for RCF in some (but not all) applications. Brown & Harrison (2012) published an article describing these materials and the history of their development. Greim et al (2014) explored analogies (e.g.…”

Section: Other Analysesmentioning

confidence: 99%

Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure

Maxim¹,

Utell

2018

Inhalation Toxicology

View full text Add to dashboard Cite

This literature review on refractory ceramic fibers (RCF) summarizes relevant information on manufacturing, processing, applications, occupational exposure, toxicology and epidemiology studies. Rodent toxicology studies conducted in the 1980s showed that RCF caused fibrosis, lung cancer and mesothelioma. Interpretation of these studies was difficult for various reasons (e.g. overload in chronic inhalation bioassays), but spurred the development of a comprehensive product stewardship program under EPA and later OSHA oversight. Epidemiology studies (both morbidity and mortality) were undertaken to learn more about possible health effects resulting from occupational exposure. No chronic animal bioassay studies on RCF have been conducted since the 1980s. The results of the ongoing epidemiology studies confirm that occupational exposure to RCF is associated with the development of pleural plaques and minor decrements in lung function, but no interstitial fibrosis or incremental lung cancer. Evidence supporting a finding that urinary tumors are associated with RCF exposure remains, but is weaker. One reported, but unconfirmed, mesothelioma was found in an individual with prior occupational asbestos exposure. An elevated SMR for leukemia was found, but was absent in the highly exposed group and has not been observed in studies of other mineral fibers. The industry will continue the product stewardship program including the mortality study.

show abstract

“…The use of AES is growing globally and accounts for an increasing proportion of total HTIW used by industry. As of 2012, AES production was about 20,000 tons per year for the European market, equal to the market size of RCF (Brown and Harrison 2012).…”

Section: Introductionmentioning

confidence: 99%

“…Where animal studies have been conducted, AES wools have shown little cause for concern, which is likely to be attributed to their low biopersistence in vivo (Bernstein et al., 1996). The reduced biopersistence of AES is due to the incorporation of soluble alkaline earth oxides, such as calcium and magnesium, into the vitreous silicate structure (Brown and Harrison, 2012; IARC, 2002), decreasing the half-life retention of fibers in the lung (Bellmann et al., 2010). Nose-only subchronic inhalation studies in rodents, demonstrated that long (>20 μm) AES fibers (150 fibers/ml, 6 h/day, 5 days/week for 90 days) induced no inflammation and had considerably lower retention times than RCF.…”

Section: Introductionmentioning

confidence: 99%

Assessing the bioactivity of crystalline silica in heated high-temperature insulation wools

Boyles

Brown

Knox

et al. 2018

Inhalation Toxicology

View full text Add to dashboard Cite

High-Temperature Insulation Wools (HTIW), such as alumino silicate wools (Refractory Ceramic Fibers) and Alkaline Earth Silicate wools, are used in high-temperature industries for thermal insulation. These materials have an amorphous glass-like structure. In some applications, exposure to high temperatures causes devitrification resulting in the formation of crystalline species including crystalline silica. The formation of this potentially carcinogenic material raises safety concerns regarding after-use handling and disposal. This study aims to determine whether cristobalite formed in HTIW is bioactive in vitro. Mouse macrophage (J774A.1) and human alveolar epithelial (A549) cell lines were exposed to pristine HTIW of different compositions, and corresponding heat-treated samples. Cell death, cytokine release, and reactive oxygen species (ROS) formation were assessed in both cell types. Cell responses to aluminum lactate-coated fibers were assessed to determine if responses were caused by crystalline silica. DQ12 α-quartz was used as positive control, and TiO2 as negative control. HTIW did not induce cell death or intracellular ROS, and their ability to induce pro-inflammatory mediator release was low. In contrast, DQ12 induced cytotoxicity, a strong pro-inflammatory response and ROS generation. The modest pro-inflammatory mediator responses of HTIW did not always coincide with the formation of cristobalite in heated fibers; therefore, we cannot confirm that devitrification of HTIW results in bioactive cristobalite in vitro. In conclusion, the biological responses to HTIW observed were not attributable to a single physicochemical characteristic; instead, a combination of physicochemical characteristics (cristobalite content, fiber chemistry, dimensions and material solubility) appear to contribute to induction of cellular responses.

show abstract

Alkaline earth silicate wools – A new generation of high temperature insulation

Cited by 25 publications

References 38 publications

A comparison of the results from intra-pleural and intra-peritoneal studies with those from inhalation and intratracheal tests for the assessment of pulmonary responses to inhalable dusts and fibres

A comparison of the results from intra-pleural and intra-peritoneal studies with those from inhalation and intratracheal tests for the assessment of pulmonary responses to inhalable dusts and fibres

Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure

Assessing the bioactivity of crystalline silica in heated high-temperature insulation wools

Contact Info

Product

Resources

About