The presence of erionite in North American geologies and the estimated mesothelioma potency by region

Abstract

Objective

Erionite is a naturally occurring fibrous mineral found in soils in some geographical regions. Known for its potency for causing mesothelioma in the Cappadocia region of Turkey, the erionite fiber has attracted interest in the United States due to its presence in a band of rock that extends from Mexico to Montana. There are few toxicology studies of erionite, but all show it to have unusually high chronic toxicity. Despite its high potency compared to asbestos fibers, erionite has no occupational or environmental exposure limits. This paper takes what has been learned about the chemical and physical characteristics of the various forms of asbestos (chrysotile, amosite, anthophyllite, and crocidolite) and predicts the potency of North American erionite fibers.

Materials and Methods

Based on the fiber potency model in Korchevskiy et al. (2019) and the available published information on erionite, the estimated mesothelioma potency factors (the proportion of mesothelioma mortality per unit cumulative exposure (f/cc-year)) for erionites in the western United States were determined.

Results and Discussion

The model predicted potency factors ranged from 0.19 to 11.25 (average ∼3.5), depending on the region. For reference, crocidolite (the most potent commercial form of asbestos) is assigned a potency factor ∼0.5.

Conclusion

The model predicted mesothelioma potency of Turkish erionite (4.53) falls in this same range of potencies as erionite found in North America. Although it can vary by region, a reasonable ratio of average mesothelioma potency based on this model is 3,000:500:100:1 comparing North American erionite, crocidolite, amosite, and chrysotile (from most potent to least potent).

Keywords:

• Asbestos
• carcinogens
• environmental exposures
• erionite
• inhalation toxicology
• mesothelioma

Disclosure statement

The purpose of this article was to share information regarding the estimated mesothelioma potencies of various erionites found in North America. The data were obtained from various published sources. Dr. Paustenbach has served as an expert in asbestos litigation for various clients since 2000. No lawyers, nor the companies they represent, asked us to prepare this article, and none were involved in the analysis of the data or conclusions of the article. Nobody other than the author’s read it prior to submission. The authors are solely responsible for the content of this article.

Data availability statement

All data came from published and publicly available literature. All calculations are presented within the article or its Supplementary materials.