Analysis of toxic air contaminant data containing concentrations below the limit of detection

Journal Article · Mon Apr 01 00:00:00 EST 1991 · Journal of the Air and Waste Management Association; (United States)

DOI:https://doi.org/10.1080/10473289.1991.10466856· OSTI ID:6059615

Rao, S T; Jia-Yeong, Ku ^[1]; Rao, K S ^[2]

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1. New York State Dept. of Environmental Conservation, Albany (United States)
2. NOAA, Oak Ridge, TN (United States)

Air quality data often contain several observations reported only as below the analytical limit of detection (LOD), resulting in censored data sets. Such censored and/or truncated data sets tend to complicate statistifcal analysis. This paper discusses various procedures for estimating mean concentration and its 95% confidence bounds from air contaminant data sets which contain values that are reported as below the LOD. A quantitative approach for assessing the uncertainty inherent in the estimated mean concentration due to (a) presence of values below the LOD in the data set, and (b) natural variability of atmospheric concentration data, is described. The utility of this approach in the analysis and interpretation of ambient pollutant concentration data is demonstrated for both hypothetical and observed singly-censored data sets, and for a multiply-censored, multi-pollutant observed concentration data set. The methodologies discussed here should be particularly useful in varifying compliance with environmental regulations, and in estimating the risks associated with long-term exposure of populations to toxic air contaminants and assessing the uncertainty associated with these estimates.

• OSTI ID: 6059615
• Journal Information: Journal of the Air and Waste Management Association; (United States), Vol. 41:4; ISSN 1047-3289
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AIR QUALITY
DATA ANALYSIS
AIR POLLUTION
CALCULATION METHODS
COMPLIANCE
ENVIRONMENTAL EXPOSURE
HEALTH HAZARDS
POLLUTANTS
POLLUTION REGULATIONS
RISK ASSESSMENT
ENVIRONMENTAL QUALITY
HAZARDS
POLLUTION
REGULATIONS
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)