Minnesota Taconite Workers Health Study: Environmental Study of Airborne Particulate Matter in Mesabi Iron Range Communities and Taconite Processing Plants - Development of Standard Operating Procedures for Particulate Collection and Gravimetric Analysis

Abstract

The Minnesota Taconite Workers Health Study (MTWHS) was initiated in 2008 and included a multicomponent study to further understand taconite worker health issues on the Mesabi Iron Range (MIR) in northeastern Minnesota. Approximately $4.9 million funding was provided by the Minnesota Legislature to conduct five separate studies related to this initiative, including:  An Occupational Exposure Assessment, conducted by the University of Minnesota School of Public Health (SPH);  A Mortality (Cause of Death) study, conducted by the University of Minnesota SPH;  Incidence studies, conducted by the University of Minnesota SPH;  A Respiratory Survey of Taconite Workers and Spouses, conducted by the University of Minnesota SPH; and  An Environmental Study of Airborne Particulate Matter, conducted by the Natural Resources Research Institute (NRRI) at the University of Minnesota Duluth (UMD). NRRI’s “Environmental Study of Airborne Particulate Matter” comprises a multi-faceted characterization of size-fractionated airborne particulate matter (PM) from MIR community “rooftop” locations, background sites, and all taconite processing facilities active between 2008 and 2014. Characterization includes gravimetric determinations, chemical characterization, mineralogical characterization, and morphological characterization. This report discusses the standard operating procedures for particle collection and gravimetric analysis. The methodology and practices that have been developed and performed have been completed in conjunction with NRRI’s Science Advisory Board and in collaboration with aerosol scientists at the University of Minnesota Department of Mechanical Engineering and University of Florida-Gainesville. As well, this report outlines the development of the sampling methodology and the history of in-house experiments conducted throughout the project to strengthen the sampling design that ultimately resulted in the development of the standard operating procedures adopted by, and practiced in, this portion of the study. Definitions for specific terms used in this document are consistent with terminology described in Appendix G.