Assessment of the Estrogenic Activity of Flue Gases from Burning Processes by Means of the Yeast Based Human Estrogen Receptor (hER) Bioassay

Abstract

Combustion processes are known to produce organic micro-pollutants in the flue gas at concentrations ranging over several orders of magnitude. Some organic micro-pollutants are suspected of being pseudo-estrogens and as such they can affect the public health. In this study, the possible application of the yeast based human estrogen receptor (hER) bioassay to screen flue gas streams for the presence of estrogenic active micro-pollutants was explored. Specifically, the protocol was modified to allow the detection and quantification of the potential estrogenic active non-polar organic micro-pollutants contained in the flue gas matrix. The modified assay was calibrated using a model estrogenic compound (17-alpha-ethinylestradiol (EE2)) dissolved in methylene chloride at concentrations ranging from 3 ng l(-1) to 3000 ng l(-1). The effective concentration to elucidate a 50% response (EC50) was 87 ng l(-1) of equivalent dissolved in methylene chloride. Samples of methylene chloride used to trap non-polar micro-pollutants in flue gas from combustion of pine wood were found to clearly register estrogenic activity by the bioassay under certain conditions. The combustion tests were performed with pinewood alone and with pine wood in the presence of both Copper-naphthenate and copper(II)chloride at 600 degrees C and 1000 degrees C. These conditions must be considered as experimental rather than practical. Overall, the results suggest that, by means of this modified assay, it is possible and warranted to screen systematically for estrogens in flue gas combustion processes.

Polycyclic Aromatic Hydrocarbons (PAHs) and Estrogenic Compounds in Experimental Flue Gas Streams

“…A major aspect to consider in this respect is the sorption efficiency of the polyurethane foam. Indeed, in a previous study (Muthumbi et al, 2002), the flue gases were scrubbed by means of methylene chloride solvent. Such an approach, although limited to small volumes of flue gas samples, yielded stronger signals of estrogenic activity.…”

“…For example, in flue gases from combustion of wood chips, 142 different compounds, which included aliphatic hydrocarbons, PAHs, carboxylic acids, alcohols, ketones, phenols, and steroids, were isolated and characterized (Simoneit et al, 2001). Incomplete combustion of wood produces estrogenic compounds (Muthumbi et al, 2002). Incomplete combustion processes occur in uncontrolled burning of domestic waste or animal carcasses and domestic heating systems operated on biomass fuels such as bark, sawdust, wood chips, charcoal, straw, whole‐plant cereals, or hay (Obernberger, 1998; Launhardt and Thoma, 2000; Gullett et al, 2001).…”

Anaerobic digestion as a core technology in sustainable management of organic matter

“…The in-depth studies over the past decades on anaerobic microbial communities and their delicate interactions and balances have given rise to a number of unexpected findings. The advances in sulphur bio-transformation, specifically with respect to sulphate reducing bacteria and their use to clean polluted groundwater and flue gases has been most startling (Sipma et al, 2000;Muthumbi et al, 2001;Muthumbi et al, 2002;Muthumbi et al, 2003). The fact that AD generates significant amounts of bicarbonate-based alkalinity has been exploited in processes to remove calcium from water (Van Langerak et al, 1997;Hammes et al, 2003a;Hammes et al, 2003b).…”