Airborne Concentrations of Chrysotile Asbestos in Serpentine Quarries and Stone Processing Facilities in Valmalenco, Italy

Abstract

Asbestos may be naturally present in rocks and soils. In some cases, there is the possibility of releasing asbestos fibres into the atmosphere from the rock or soil, subsequently exposing workers and the general population, which can lead to an increased risk of developing asbestos-related diseases. In the present study, air contaminated with asbestos fibres released from serpentinites was investigated in occupational settings (quarries and processing factories) and in the environment close to working facilities and at urban sites. The only naturally occurrence of asbestos found in Valmalenco area was chrysotile; amphibole fibres were never detected. An experimental cut-off diameter of 0.25 μm was established for distinguishing between Valmalenco chrysotile and antigorite single fibres using selected area electron diffraction analyses. Air contamination from chrysotile fibres in the examined occupational settings was site-dependent as the degree of asbestos contamination of Valmalenco serpentinites is highly variable from place to place. Block cutting of massive serpentinites with multiple blades or discs and drilling at the quarry sites that had the highest levels of asbestos contamination generated the highest exposures to (i.e. over the occupational exposure limits) asbestos. Conversely, working activities on foliated serpentinites produced airborne chrysotile concentrations comparable with ambient levels. Environmental chrysotile concentrations were always below the Italian limit for life environments (0.002 f ml(-1)), except for one sample collected at a quarry property boundary. The present exposure assessment study should encourage the development of an effective and concordant policy for proper use of asbestos-bearing rocks and soils as well as for the protection of public health.

Impact of Naturally Occurring Asbestos on Asbestos Ban: Regulations and Experience of the Republic of Korea

“…The number of chrysotile fibers present at the lowest level of detection by XRD can be about 10 9 fibers per milligram of talc powders when analyzed by TEM, which might lead to significant exposure to users of talc end products [ 50 ]. Several studies reported that workers who mine or process minerals containing NOA as impurities or those who use them as raw materials can be exposed to concentrations that exceed the occupational exposure limit of asbestos [ 53 , 54 , 55 ]. In 2011, the serpentinite produced from NOA-contaminated serpentine mines in Korea exhibited an asbestos content far less than the 1% criterion, although the maximum concentration of asbestos in the air to which workers were exposed was 0.076 f/cc, which was 76% of the exposure limit [ 43 ].…”

Using GIS to Estimate Population at Risk Because of Residence Proximity to Asbestos Processing Facilities in Colombia

“…This analysis, as rigorous as it was, should be read only as an estimation exercise, considering that it was based on distances at which an increased risk of ARD has been observed in other locations of the world, but no asbestos exposure campaigns have been conducted in Colombia in the surroundings of asbestos facilities or the mine, similarly to what happens in most low-and middle-income countries. Only sampling campaigns could prove if the real exposure to asbestos fibers in these areas occurred, as it has been exemplified by several cases, including serpentine quarries in Italy [40], an asbestos textile factory in Indonesia [41], and an asbestos cement sheet manufacturing plant in India [42]. However, since asbestos has already been banned in Colombia, the opportunity to measure asbestos concentrations in the air surrounding asbestos processing facilities and the mine is no longer available.…”

RoB-SPEO: A tool for assessing risk of bias in studies estimating the prevalence of exposure to occupational risk factors from the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury

“…For each systematic review, we generated one random number between 1 and the highest number allocated to any study record for the systematic review using an online tool ( https://www.random.org/ ) and then selected the study record with this number for pilot tests. This ensured pilot testing on a sample of five randomly drawn study records of prevalence studies of exposure with ergonomic, physical, chemical and psychosocial occupational risk factors ( Cattaneo et al, 2012 ; Gies et al, 2009 ; Strauss et al, 2014 ; Kim et al, 2016 ; Hartling et al, 2013 ).…”