Respiratory Toxicity of Nano Airborne Particulate Matter

Background and aim: toxicological studies of atmospheric nano particles (nps) showed that nps consistently induced mild yet significant pulmonary inflammatory responses and extrapulmonary organs. it was reported that nps are inhaled deep into the body leading to high deposition in the alveolar and respiratory tract regions. reliable characterization of nanoparticles in the air is vital for developing toxicological assessments. the aims of this study are characterization of atmospheric airborne particles (from micro to nano) by a new device sampler and investigation of cytotoxicity of one of the main natural elements in ultra-fine section.methods: a simulation device was manufactured based on the mechanisms of sedimentation of suspended particles in the lungs. atmospheric particles were collected by size (from 10µm to 50nm) in 8.5 l/m flow rate. samples from each stage was analyzed by sem-edx. elemental content and particle size distribution were investigated. cytotoxicity of silica nanoparticles as one of the main elements investigated in human lung epithelial (a549) cells by cell viability (mtt assay).results: nanoparticles are mainly in the agglomeration and aggregation forms. some elements such as: si, ti, mg, p, s, al, fe, pb, v were detected (in a sand mine atmosphere) in alveolar parts by the lung simulation method. the half maximal inhibitory concentration of sio2 nps on (a549) cells is 1.6 mg/ml.conclusion: toxic elements in nanometer size can penetrate into alveolar parts of the lung and characterizations and further studied are very essentials.