Investigation of magnetic particulate matter inside animals’ lung tissue: preliminary results

Abstract

In this preliminary study I investigate the possibility of using magnetic techniques to analyse particulate matter trapped within the lung tissue from four deceased animals from in and near Munich, Germany. This is the first in vitro magnetic analysis of animal lung tissue. The four animals were three cats and a dog. The animals had not been studied in any previous laboratory experiments, and it is assumed that the magnetic signature was from particulate matter trapped within the lungs; however, the bulk analysis in this study did not discriminate between a biogenic or inorganic origin of the magnetic signal. Magnetic measurements were made on sub-samples of each lung. To fix the magnetic minerals within the lung tissue, the samples were cooled to 77 K, and their saturation isothermal remanence measured. For a few select samples the isothermal remanence acquisition curves were measured, plus thermomagnetic warming curves. The findings suggest that the main magnetic mineral is magnetite-like, in small concentrations (∼100s ppb) and likely consists of particles <100 nm in size. This is consistent with the magnetic signature of urban particulate matter thought to be of vehicular origin The cat from the countryside was found to have a magnetic concentration ∼50% that of the two urban cats, however, this cat was also significantly younger. The countryside dog had a concentration slightly higher than that of the two urban cats; however, the data set is too small to be statistically significant.