Environmental monitoring of hydrogen fluoride using passive samplers

Publikations-Art

Zeitschriftenbeitrag

Autoren

Franzaring, J., Grass, H., Diehlmann, A., Fangmeier, A.

Erscheinungsjahr

2008

Veröffentlicht in

Gefahrstoffe - Reinhaltung der Luft

Band/Volume

68/

Seite (von - bis)

499-502

Hydrogen fluoride (HF) is one of the most phytotoxic air pollutants and even concentrations below 10 ppb may cause visible injury in sensitive plant species. Due to the uptake of atmosphreic fluorides by the vegetation and the accumulation of fluorine in the food chain, environmental monitoring in the vicinity of large emitters has often been performed relying on plants as bioindicators only. However, there are currently no approved devices available to determine atmospheric levels of HF in the lower concentration range. In this paper results from a study are presented in which passive samplers were applied for more than one year to monitor ambient levels of HF at various locations around a large chemical factory. Generally, mean HF levels were only slightly above the limit of detection and remained well below the environmental threshold level for this air pollutant. Although the results from the passive sampler study well represented the spatial dispersion pattern of HF, high standard deviations were observed between the three replicates. Reasons for the high variability were presumably the hygroscopy of the adsorber matreial triethanolamine (TEA) and the water films which formed on diffusive bodies at moist weather leading to the wash-off of adsorbed fluorides. In conclusion, advanced methods for passive sampling of HF with less hydroscopic adsorbents and high sampling rates will have to be elaborated for the relaible monitoring of gaseous fluorides.