Gardening in greenhouses as a risk factor for silicosis

Silicosis is a typical occupational disease, although some cases caused by non-industrial exposure have also been reported. We saw a 53-year-old male gardener with recurrent non-productive cough. A routine radiograph of the chest showed bilateral pulmonary nodules and subsequent computed tomography suggested that the infiltrates could be metastases. Open lung biopsy revealed nodules consisting of fibrotic tissue while the presence of birefringent silica particles was observed by polarised light microscopy. Mineralogical analysis of the substrata from the patient’s workplace revealed an SiO2 concentration of 31%. This case indicates that the inhalation of siliceous particles in a closed environment such as a greenhouse is a risk factor for silicosis.