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Lung Dust Loads Monitored by Non-invasive Magnetometric Method

In the contaminated environment and particularly in some working environments, exposed persons inhale polluting substances for a long time. In special but not unusual cases, the contaminating substances are particles with magnetic properties. They can be present in foundry dust and fumes, welding fumes and partially in the coil powder or as microparticles arising during cutting the iron workpieces. The lung contamination with these magnetic particles occurs at welders, miners, iron industry workers or special professions of machine industry (grinders, milling cutters, etc.).

The principle of the noninvasive magnetometric monitoring of the particles with ferro- or ferrimagnetic properties in the lungs is based on measurement of the magnetic field changes at proximity of the chest. Within the framework of cooperation with Clinic for Occupational Diseases (Medical Faculty of the Comenius University, Bratislava) the selected subjects have been magnetized in an uniform magnetic field 2mT during 1minute and then measured 30 seconds after finishing the magnetization. The remanent magnetic field Bn at the chest produced by the particles in the lungs after removing the applied field was measured. The equivalent spectral sensitivity of the measuring RF SQUID system is 20x10^-15 T Hz^-1/2 in the unit frequency range. The whole measuring system is placed in the RF shielded environment, unbalancing of the gradiometer is of the order of 10^-4. The final sensitivity of the system for magnetizing field given above was estimated at 80-120mg of Fe or ferrite in the lungs.

... to Lab. of Magnetometry ... to Institute of Measurement Science ... to Slovak Academy of Sciences

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Last updated: March 17, 1997