High incidence of lung cancer and malignant mesothelioma linked to erionite fibre exposure in a rural community in Central Mexico

Our plain-English summary of High incidence of lung cancer and malignant mesothelioma linked to erionite fibre exposure in a rural community in Central Mexico, by M.A. Ortega-Guerrero, G. Carrasco-Núñez, H. Barragán-Campos, et al (Occupational and Environmental Medicine, 2015).

The study

• Authors: M.A. Ortega-Guerrero, G. Carrasco-Núñez, H. Barragán-Campos, M.R. Ortega
• Journal: Occupational and Environmental Medicine
• Published: 2015;72(3):216-8
• Cited by: 33 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Objective: To report the high incidence of lung cancer (LC) and malignant mesothelioma (MM) linked to environmental exposure to erionite fibres in a rural village of central Mexico.

Methods: This is a retrospective survey of clinical and mortality records from the years 2000-2012, accompanied by an environmental survey for nine Group-1 lung and pleura carcinogenic agents listed by the International Agency for Research on Cancer (IARC).

Results: Out of a total of 45 deaths between 2000 and 2012, 14 deaths correspond to different neoplasms of the lung, and at least four deaths to MM. The ages at diagnosis of MM were between 30 and 54 years. Annual age-standardised mortality rates per thousand due to LC and MM in the village (age >20 years) are 7.09 and 2.48 for males, and 4.75 and 1.05 for females, respectively. Erionite fibres were found in exposed rocks and soils, which can easily become airborne and be carried into streets and recreational areas near schools and homes. Other carcinogenic elements and minerals are found only in trace amounts, except for quartz dust and asbestos (chrysotile) cement sheeting, which are also present in the neighbouring villages.

Conclusions: These results indicate that environmental exposure to erionite is the main cause of the high rates of MM mortality in the Village of Tierra Blanca, supporting previous similar reports for people exposed to erionite fibres in villages in Turkey.

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In plain English

This report studied Tierra Blanca de Abajo, a Mexican village of 450 people. The authors reviewed clinical and death records from 2000 to 2012. They also collected 206 rock, soil and building-material samples; different samples were analysed for nine IARC-listed carcinogens, including erionite and asbestos. Of 45 deaths, 14 were from lung neoplasms and at least four from malignant mesothelioma (three men, one woman, aged 30 to 54 at diagnosis). Among residents over 20, age-standardised mortality rates per 1000 person-years were 7.09 for lung cancer (95% CI 2.99 to 15.24) and 2.48 for mesothelioma (0.49 to 8.90) in men, and 4.75 (1.67 to 11.34) and 1.05 (0.03 to 6.26) in women. Erionite fibres were found in zeolitic tuff, old alluvial terraces and adobe bricks. Chrysotile asbestos cement roofing was present, but similar conditions exist in nearby villages where lung cancer is not the main cause of death. Family members reported no occupational asbestos exposure. The authors concluded that environmental erionite exposure is the main cause of the high mesothelioma mortality. They believed some recorded lung cancers were actually mesothelioma.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Short report: retrospective survey of clinical and mortality records (2000 to 2012) combined with an environmental survey of rocks, soils and building materials
• Who was studied: Residents of the rural village of Tierra Blanca de Abajo, Municipality of San Miguel de Allende, Guanajuato, Mexico. The population was 450 and stable over 2000 to 2012. Rates were calculated for residents over 20 years (134 males and 120 females in 2012).
• Exposure: Environmental exposure to erionite fibres found in three places: a zeolitic tuff (about 0.1 to 1% by volume), fine-grained old-alluvial terraces (about 0.01%), and adobe house bricks. Chrysotile asbestos cement roofing sheets were also present. The authors collected 206 samples; different samples were analysed for nine IARC-listed carcinogens.
• Main results:
  • There were 45 deaths in the village from 2000 to 2012. Of these, 14 were from different neoplasms of the lung and at least four were from malignant mesothelioma.
  • Of the four confirmed mesothelioma cases, three were male and one was female. Their ages at diagnosis were 30 to 54 years.
  • Annual age-standardised mortality rates per 1000 among village residents over 20 years were 7.09 for lung cancer and 2.48 for malignant mesothelioma in males, and 4.75 for lung cancer and 1.05 for malignant mesothelioma in females.
  • The 95% confidence intervals for the mesothelioma rates were 0.49 to 8.90 for males and 0.03 to 6.26 for females.
  • The 95% confidence intervals for the lung cancer rates were 2.99 to 15.24 for males and 1.67 to 11.34 for females.
  • For comparison, the article gives national lung cancer rates for Mexico per 100 000 inhabitants: 13.2 for males and 5.4 for females. These are in different units from the village rates, which are per 1000.
  • Arsenic, beryllium, cadmium, chromium and nickel were below concentrations deemed harmful to humans.
  • Chrysotile asbestos cement roofing was the only asbestos source identified in the village. The authors noted that similar conditions exist in nearby villages where lung cancer is not the main cause of death.
  • Individual erionite fibres measured 0.5 to 2 micrometres in diameter and 50 to 100 micrometres in length.
  • There was no occupational exposure to asbestos; this information came from family members. Smoking in the village was slightly lower than in the state, with about 5% smoking more than 10 cigarettes per day. Women were exposed to wood smoke in kitchens.
• The authors' conclusion: The authors concluded that environmental exposure to erionite is the main cause of the high malignant mesothelioma mortality in Tierra Blanca. They said this supports earlier reports from erionite-exposed villages in Turkey, and that the population needs heightened surveillance and efforts to reduce exposure.
• Limitations the authors state:
  • The study lacked more detailed diagnoses of malignant mesothelioma.
  • The authors believe some cases recorded as lung cancer were actually mesothelioma.
  • Medical information was widely dispersed across various hospitals in the country.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Lung Cancer, Mesothelioma, erionite, Environmental Exposure, Pleura, Carcinogenic, IARC, Neoplasm.

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