POM (polyoxymethylene) is a plastic material which establishes equilibrium with the organic pollutants in the water phase when exposed over time, typically 30-90 days. It is therefore suitable as an adsorption media for passive sampling.
The concentration of organic pollutants in water are calculated using the measured level of organic contaminants in the POM and established equilibrium coefficients between POM and water. It is possible to quantify very low concentrations of PAHs and PCBs, with lower detection limit down to 0.1-pg / l for PCB and 0.1 ng / l for PAH. This has been documented with extensive testing in the laboratory and a number of field trials. Recent research has confirmed the suitability of POM for dioxins and furans, as well as detection limits down to pg/m3
Two formats are available:
- POM-76 (sheet) for deployment in the POM cage sampler, or for use in laboratory shake tests
- POM-55 (strips) for flexible deployment options
Applications and benefits
POM is suitable for fresh water, sea water, leachate, wastewater and groundwater; and it can be used for various applications, for example:
- Verification of water quality according to the water framework directive (Vanndirektivet) and discharge permits
- Mapping of water quality monitoring programs for risk assessment and documentation of measures efficiency
Validation and analysis
Validation studies have previously been performed to establish the equilibrium distribution of the compounds between the POM and the aqueous phase. After a suitable deployment period, the samplers are retrieved and the POM analyzed on high-resolution gas chromatograph (GC-MS). The GC-MS results together with the equilibrium distribution coefficients provide the concentration of free dissolved PAHs and PCBs in water.
Laboratory analysis of the POM membranes for PAH-16 og PCB-7 in water is available from a commercial laboratory service in Norway.
Research at NGI on POM for passive sampling applications is done by
Gerard Cornelissen • Amy Oen • Hans Peter Arp • Sarah Hale
To purchase these materials, contact WAG: Commercial inquiries
Contact the reseachers regarding related R & D: Related research