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First Identification of Pulmonary Asbestos Fibres in a Spanish Population

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Introduction: This study aimed to characterize, for the first time in Spain, the type of asbestos fibres (AF) in the lungs of exposed and non-exposed populations. Materials and methods: Lung samples from 38 subjects living in Barcelona and Ferrol, Spain, were studied, which were divided into three groups: Group A-five subjects without known respiratory disease; Group B-20 ex-shipyard workers and Group C-13 patients with lung cancer. After eliminating the organic material, the inorganic residue was analysed using electronic microscopy (EM). To identify the type of fibre, the samples were analysed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Results: All the fibres identified corresponded to amphiboles (crocidolite 45%, anthophyllite 22%, tremolite 16%, amosite 15% and actinolite 3%). In 14 patients (37%), a single type of asbestos was found in the lungs (amosite in two, actinolite in one, anthophyllite in four, crocidolite in five and tremolite in two). Forty-six percent of the AF analysed had a length > 5 µm and a diameter < 0.2 µm. Conclusions: The results of this study provide the first data on the type of asbestos retained in the lung of Spanish population. A particularly striking finding is the exclusive retention of amphiboles, which suggests that chrysotile is eliminated after inhalation. Our findings support estimations considering Spain and other southern European countries with similar asbestos imports and consumption at a high risk to develop asbestos-related diseases in the years to come.
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OCCUPATIONAL LUNG DISEASE
First Identification of Pulmonary Asbestos Fibres in a Spanish
Population
M. I. Velasco-Garcı
´a
1,2,3
M. J. Cruz
1,2
C. Diego
4
M. A. Montero
5
D. A
´lvarez-Simo
´n
1,2
J. Ferrer
1,2
Received: 14 January 2017 / Accepted: 29 July 2017 / Published online: 8 August 2017
ÓSpringer Science+Business Media, LLC 2017
Abstract
Introduction This study aimed to characterize, for the first
time in Spain, the type of asbestos fibres (AF) in the lungs
of exposed and non-exposed populations.
Materials and Methods Lung samples from 38 subjects
living in Barcelona and Ferrol, Spain, were studied, which
were divided into three groups: Group A—five subjects
without known respiratory disease; Group B—20 ex-
shipyard workers and Group C—13 patients with lung
cancer. After eliminating the organic material, the inor-
ganic residue was analysed using electronic microscopy
(EM). To identify the type of fibre, the samples were
analysed by scanning electron microscopy (SEM) and
energy-dispersive X-ray spectroscopy (EDX).
Results All the fibres identified corresponded to amphi-
boles (crocidolite 45%, anthophyllite 22%, tremolite 16%,
amosite 15% and actinolite 3%). In 14 patients (37%), a
single type of asbestos was found in the lungs (amosite in
two, actinolite in one, anthophyllite in four, crocidolite in
five and tremolite in two). Forty-six percent of the AF
analysed had a length [5lm and a diameter \0.2 lm.
Conclusions The results of this study provide the first data
on the type of asbestos retained in the lung of Spanish
population. A particularly striking finding is the exclusive
retention of amphiboles, which suggests that chrysotile is
eliminated after inhalation. Our findings support estima-
tions considering Spain and other southern European
countries with similar asbestos imports and consumption at
a high risk to develop asbestos-related diseases in the years
to come.
Keywords Asbestos bodies Lung cancer Asbestos fibres
Introduction
Asbestos is the generic name given to a group of silicate
minerals. The most common are amphiboles: amosite,
crocidolite, tremolite, actinolite and anthophyllite, and the
serpentine chrysotile. These forms differ in terms of their
chemical structure, their biopersistence in humans and their
toxicity. Inhaled asbestos fibres are deposited in the res-
piratory system where they interact with epithelial cells and
alveolar macrophages to produce an immune response. As
described extensively in the scientific literature, exposure
to asbestos has been associated with asbestosis, mesothe-
lioma, lung cancer and benign pleural lesions [13].
In Spain, asbestos was widely used in industry for many
years. Its use in this country reached its peak between 1970
and 1990. In 1992, Spain was the second largest European
importer with 25,428 tons [4], and the total ban on the use
of the mineral did not come until 2002. This means that a
large number of workers have been exposed to asbestos
and will remain exposed in the future, given its
&M. J. Cruz
mj.cruz@vhir.org
1
Pulmonology Department, Hospital Universitari Vall
d’Hebron, Passeig Vall d’Hebron, 119-129, 08035 Barcelona,
Spain
2
Ciber Enfermedades Respiratorias (CibeRes), Barcelona,
Spain
3
Departament de Medicina, Universitat Auto
`noma de
Barcelona, Barcelona, Spain
4
Pulmonology Department Hospital Arquitecto Marcide,
Ferrol, Spain
5
Pathology Department, Hospital Universitario Vall d’Hebron,
Barcelona, Spain
123
Lung (2017) 195:671–677
DOI 10.1007/s00408-017-0042-1
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Velasco-Garcia et al. [35] recently analysed lung tissues of 20 Spanish ex-shipyard workers by means of scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX); no chrysotile fibres were found although chrysotile was the predominant asbestos type used. ...
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Although there is no dispute among independent scientists about the carcinogenic and fibrogenic effects of chrysotile, the asbestos industry has been continuously and success-fully acting to cast doubts on its harm. Another approach including asbestos insurance entities is to refuse compensa-tion by raising the bar and fight criminal prosecution for asbestos-related diseases by the help of paid scientists. A recent publication on asbestos fibre burden in human lungs fits well in this context. The claim that chrysotile fibres are biopersistent in human lung is not based on the data provided by these authors, and, additionally, exhibits ser-ious inconsistencies and obvious mismeasurements and significant methodological problems. The conclusion of the authors that fibre analysis of workersʼ lungs “is of high significance for differential diagnosis, risk assessment and occupational compensation” is unfounded and reprehensi-ble. Also the available literature, the statements of the WHO, IARC, other decisive independent international orga-nizations, and all our experience provide abundant evi-dence to the contrary. Note, the method is generally re-stricted to research only and is not recognized for diagnostic purpose and compensation in any other country. In conclusion, fibre counting in lung tissues should not be used to estimate former exposure to chrysotile comprising c. 94 %of applied asbestos in Germany. The authors claim that the analyses can improve the compensation rates in Germany. However, the opposite has been the case; it significantly worsens the non-justified denial of well-substantiated com-pensation claims.
... Velasco-Garcia et al. [35] recently analysed lung tissues of 20 Spanish ex-shipyard workers by means of scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX); no chrysotile fibres were found although chrysotile was the predominant asbestos type used. ...
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Although there is no dispute among independent scientists about the carcinogenic and fibrogenic effects of chrysotile, the asbestos industry has been continuously and successfully acting to cast doubts on its harm. Another approach including asbestos insurance entities is to refuse compensation by raising the bar and fight criminal prosecution for asbestos-related diseases by the help of paid scientists. A recent publication on asbestos fibre burden in human lungs fits well in this context. The claim that chrysotile fibres are biopersistent in human lung is not based on the data provided by these authors, and, additionally, exhibits serious inconsistencies and obvious mismeasurements and significant methodological problems. The conclusion of the authors that fibre analysis of workers' lungs "is of high significance for differential diagnosis, risk assessment and occupational compensation" is unfounded and reprehensible. Also the available literature, the statements of the WHO, IARC, other decisive independent international organizations, and all our experience provide abundant evidence to the contrary. Note, the method is generally restricted to research only and is not recognized for diagnostic purpose and compensation in any other country. In conclusion, fibre counting in lung tissues should not be used to estimate former exposure to chrysotile comprising c. 94 % of applied asbestos in Germany. The authors claim that the analyses can improve the compensation rates in Germany. However, the opposite has been the case; it significantly worsens the non-justified denial of well-substantiated compensation claims. © Georg Thieme Verlag KG Stuttgart · New York.
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