Steven N. Chillrud, PhD
I am a Senior Doherty Research Scientist at Lamont-Doherty Earth Observatory and co-Director of the Exposure Assessment Facility Core of Columbia University's Center for Environmental Health in Northern Manhattan. I describe myself as an environmental geochemist interested in public health research.
Much of my research is focused on the role of particles in the transport, behavior and fate of chemical contaminants. These particles can be fine-grained sediments in surface water bodies such as the Hudson River, sandy particles in groundwater aquifers, or airborne particles in indoor and outdoor settings. My air pollution work includes understanding the sources, behavior and exposure pathways of airborne contaminants as well as designing and testing new air monitoring devices, either to be used at fixed indoor and outdoor locations or to be worn by people. Much of my work is done in collaboration with public health investigators to work on both local and international health issues.
Air Pollution and Exposure Assessment
My research on air pollution focuses on methods for identifying sources and exposure pathways as well as defining the levels of exposures for individuals, which is critical for studies focused on understanding the health effects of the respiration of different compounds and complex mixtures. [more...]
In collaboration with a number of other investigators at Columbia University, I also carry out research on the behavior and cycling of arsenic species at anthropogenically impacted sites. Arsenic is of particular concern due to its prevalence, both at US Superfund Sites, where it is the second most common contaminant of concern, and globally, as approximately 40 million people drink water with dangerously elevated levels of dissolved As. In our work, we have been studying arsenic cycling at a former biocide manufacturing plant in southern NJ (Vineland Superfund Site) and at a number of old unlined landfills in Maine and New York. At the chemical site, our primary aims include lab and field experiments to investigate the use of subsurface additions of chemical amendments to mobilize arsenic and thus accelerate remediation at Vineland and potentially other sites that are already using pump and treat remediation strategies. Interestingly, unlined landfills do not need to have any arsenical wastes to be able to mobilize naturally occurring arsenic from aquifer sediments into downgradient groundwaters. [more...]
Contaminant Transport in the Hudson River Basin
Interpretation of the sediment record depends on an accurate determination of an age vs. depth relationship within the sediment column, most often achieved by the use of radionuclide indicators such as 137Cs, 210Pb, and 7Be. [more...]
World Trade Center Environmental Contaminant Database
I was part of the development team for the World Trade Center Environmental Contaminant Database (WTCECD), a publicly-available repository of air monitoring data in the New York/New Jersey area. The WTCECD includes over three decades of ambient air quality data from fixed-site monitoring stations in New York City and the state of New Jersey. [more...]