Airborne Hexavalent Chromium Concentration and Particle Size Distribution in NJ Meadowlands District-A Pilot Study

Zhi-Hua Tina Fan1, Chang-Ho Yu1, Jin Young Shin2, Christine Hobble2, Francisco Artigas2

1Exposure Science Division, Department of Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School and Environmental and Occupational Health Sciences Institute, 170 Frelinghuysen Road, Piscataway, NJ 08854 2Meadowlands Environmental Research Institute,,New Jersey Meadowlands Commission,2 DeKorte Park Plaza, Lyndhurst NJ 07071

     Abstract Number: 873
     Last modified: August 10, 2010

Abstract
Airborne hexavalent chromium (Cr-VI) is a known pulmonary carcinogen and can be emitted from both natural and anthropogenic sources, including diesel emission. New Jersey Meadowlands (NJ ML) district is located close to NJ Turnpike (NJTPK), which has high truck traffic volume, and only several miles away from Kearny and Jersey City, areas with more than 200 historic chromium waste sites. The Cr-VI contaminated particles may be transported to Meadowlands area and contribute to Cr-VI air pollution. However, Cr-VI was not measured in air quality monitoring programs in ML area. Also, the particle size distribution of Cr-VI in ambient air was not characterized. This pilot study measured the Cr-VI concentration in PM2.5 for 2 weeks simultaneously at two sites, MERI site (~ 700 m from NJTPK) and William site (~ 50 m from NJTPK), during one winter and summer season. Cr-VI was detected in all of the field samples, with a mean±SD (median) of 0.52±0.32 (0.47) ng/m3 at the MERI site and 0.40±0.20 (0.35) ng/m3 at the William site. These values are marginal higher than Cr-VI in other NJ urban areas, but the difference in Cr-VI concentrations between the two sites were not significant. The Cr-VI distribution as a function of particle size at the William site was also determined by using a MOUDI sampler with 8 particle sizes, ranging from 0.18 to 18 micro-m. It was found that the Cr-VI was enriched in the particles with diameter less than 2.5 micro-m. The diesel powered vehicles, ozone and precipitation were found to be significant variables contributing to the variability of Cr-VI concentration in the NJ Meadowlands area.