Distribution of manganese soil concentrations surrounding ferromanganese plants in Brescia, Italy
Abstract
Over the past 170 years, scientists have hypothesized that exposure to manganese in both environmental and occupational settings is linked with neurological disorders similar to Parkinson’s Disease, including disturbances of gait, dystonia, bradyknesia, and tremor. Ferromanganese plants produce large amounts of iron and manganese particulate that are released into the air and expose the surrounding communities. The objective of this study is to determine manganese concentrations in soils surrounding ferromanganese plants in Brescia, Italy. A further study will then investigate the use of these soil levels as a surrogate for the air concentrations resulting from pollution released to the air and deposited on the ground. This will allow future correlations between manganese air levels and soil deposition rates for exposure profiling. The hypotheses for this study are that: (1) X-ray fluorescence (XRF) can distinguish between background levels of manganese and levels of pollution deposition, (2) Levels of manganese decrease with distance plant where wind direction and topographical features affect the distance and direction of deposition. Surface soil metal concentrations were measured using a portable XRF gun and locations recorded using a Global Positioning System (GPS). The GPS and metal concentration data were then manipulated with a variety of Geographical Information System (GIS) techniques. Inverse Distance Weighted spatial interpolations were performed on manganese concentrations. Spatial statistics were performed on Digital Elevation Models and manganese interpolations to determine manganese concentrations at specified elevations. Our results showed that XRF distinguished between manganese polluted areas and non-polluted areas. Surface manganese levels decrease as the distance from the plant increases. These concentration gradients orient with wind direction and are influenced by local topographical features such as local mountains and valleys of the pre-Alps. Our research demonstrates a successful combination of environmental exposure assessment with GIS/GPS which will help investigators determine exposure profiles for individuals who live in the vicinity of manganese air pollution point sources from simple soil characterization.
Degree
M.S.
Advisors
Zimmerman, Purdue University.
Subject Area
Toxicology|Surgery|Biogeochemistry|Soil sciences
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.