In addition, local inflammation in acute silicosis
is closely associated with various biological pathways, including abnormal cell signaling, increased oxidative stress, protease-antiprotease imbalance and induction of apoptosis (13), among others (Figure 2).
In exceptional cases, silicosis develops after as little as 5-10 years (accelerated silicosis), or even faster after weeks to years following very high silica concentrations (acute silicosis
or silicoproteinosis) .
Accelerated silicosis occurs after 5-10 years of exposure to higher silica levels, and acute silicosis
can occur after only weeks or months of exposure to extremely high silica concentrations.
Following exposure to exceedingly high silica concentrations, acute silicosis
may develop in weeks or months, whereas accelerated silicosis may develop after 5-10 years exposure to higher silica levels (1).
Falcao et al., "Apoptosis underlies immunopathogenic mechanisms in acute silicosis
," American Journal of Respiratory Cell and Molecular Biology, vol.
The onset of symptoms takes longer than in acute silicosis
Silicosis is a disease that affects the tissue and space around the air sacs of the lungs due to inhalation of mixed dusts containing silicates.4 It occurs in three ways chronic silicosis which is progressive lung disease characterized by development of scar in response to inhalation of silicates bearing dusts; acute silicosis
is the destruction of airways in order for the lungs to become heavy and rigid as air spaces are filled with granular silicate particles and accelerated silicosis which is exposure to silica dusts of almost pure quartz in which the victims show no clinical abnormalities until the condition becomes acute resulting in a decrease of lung function.5
Accelerated silicosis may occur within two years of initial exposure while 'acute silicosis
develops rapidly after intense exposure generally to fine particles of freshly fractured crystalline silica' (2), the very work experience that killed Sydney's rockchoppers and sewer miners a century ago.
Because apoptosis is believed to play an essential role in the inflammation associated with one pneumoconiosis, acute silicosis
, and because inflammation increased as CYP1A1 activity decreased in the rat model of coal workers' pneumoconiosis (Ghanem et al.
But acute silicosis
can occur after only a few months of extremely high concentrations of respirable silica.
Sand blasters, rock drillers, and silica-flour millers all face a high risk of acute silicosis
, a life-threatening inflammatory disease that disables its victims--sometimes in as little as 5 years--by killing lung cells and letting their liquids leak out.