A wide range of household sources may potentially contribute to contaminant loads in domestic wastewater. Typically domestic wastewater is combined and transported as a single waste stream, however, there is considerable variation in the pollutant and pathogen content of wastewater derived from different activities within the home (e.g. toilet flushing, dish washing, bathing etc.). In Ireland, the issue of unsewered wastewater treatment systems often located in rural areas and estimated to number over 400,000, constitutes a significant diffuse risk to both surface & groundwater. DCU & CIT have teamed up with DkIT and their project partners to carry out a preliminary investigation into the levels of priority & hazardous substances in domestic wastewater from a number of single dwelling houses within the Lough Muckno Catchment, Co. Monaghan and an integrated constructed wetland (ICW) on the grounds of the Castle Leslie Estate in Glaslough, Co. Monaghan.