A 13-Week Comparison of Passive and Continuous Ozone Monitors at Forested Sites in North-Central Pennsylvania

Abstract

Ogawa passive O 3 samplers were used in a 13-week study (June 1-September 1, 1999) involving 11 forested and mountaintop sites in north-central Pennsylvania. Four of the sites were collocated with TECO model 49 O 3 analyzers. A significant correlation (p < 0.0001) was found for 24-hr average weekly O 3 concentrations between the two methodologies at the four sites with collocated monitors. As expected, there were positive relationships between increasing elevation of the sites and increasing O 3 concentrations. No O 3 exposure patterns were found on a west-to-east or south-to-north basis; however, the area known for lower O 3 exposures within a smaller subsection of the study area showed consistently lower O 3 exposures. Preliminary results regarding relationships of symptom responses within O 3 -sensitive bioindicators are also presented with black cherry (Prunus serotina, Ehrh.) and common milkweed (Asclepias syriaca, L.) showing clear evidence of increasing injury with increasing O 3 exposures. Due to the extremely dry conditions encountered in north-central Pennsylvania during the 1999 growing season, O 3 -induced symptoms were sporadic and quite delayed until late-season rains during the latter portion of the observation period.

Estimation of Ozone Concentration in a Valley of the Alps Mountains Based on Bel-W3 Tobacco Leaf Injury

“…Tobacco plants can be used either with a sufficient development (approximately 2 months old) (Toncelli and Lorenzini 1999;Vergé et al 2002) for several weeks exposure or at young developmental stage and with every week plant change (Lorenzini's miniaturized ozone biomonitoring kits) (Lorenzini 1994;Toncelli and Lorenzini 1999). Some authors have recently turned to passive samplers for measuring ambient ozone concentrations in ecological assessments Smith 1991;Hewitt and Terry 1992;Bytnerowicz et al 1993;Lefohn and Foley 1993;Grosjean et al 1995;Manning et al 1996;Blum et al 1997;Grünhage et al 1997;Bytnerowicz et al 1998;Cox and Malcolm 1999;Krupa and Legge 2000;Krupa et al 2001;Skelly et al 2001;Gerosa et al 2007). In addition to yielding real concentrations of pollutants in ambient air, this method offers several other advantages.…”

Field comparison of passive samplers versus UV-photometric analyser to measure surface ozone in a Mediterranean area

“…This methodology has been successfully employed for assessing exposure to ambient ozone levels. [4][5][6] The lack of field studies validating the Radiello passive sampling methodology in a Mediterranean area makes it convenient to validate the methodology in such an area before employing the passive samplers in future studies. The validation of a method has to consider method-inherent criteria, which are precision, bias, accuracy, selectivity and detection limit.…”