Proceedings

There has been increasing interest in perfluorinated chemicals such as perfluorooctane sulphonate
(PFOS). PFOS has been shown to be toxic, persistent and bioaccumulative in the environment and is a
focus for restriction within the European Union.

Monitoring was conducted in raw and treated drinking water at 20 sites in England, covering 4 seasonal
periods. Sites were selected which treat surface and groundwater in rural or industrial areas and near
airfields. The method used was LCMS/MS in negative ion electrospray (ESI) mode which achieved an LOD of 0.011 µg/l for PFOS.

The results of the monitoring indicate that PFOS does not appear to be a widespread contaminant of raw
and treated drinking water in England. When detected, the water course was considered at higher risk
due to a specific incident, or the presence of a local potential source of contamination such as an airfield.
In all cases, concentrations were very low and below the current Drinking Water Inspectorate drinking
water guidance levels for England and Wales.

Key Words
Drinking water, England, Method development, Monitoring, Perfluorooctane sulphonate, PFOS, Raw
water