Passive sampling as a tool for time-integrated analysis of
metals in marine waters using ICP-MS-MS
Jördis Petersen1,2, Daniel Pröfrock1, Jose A.C. Broekaert2, Andreas Prange1
1Helmholtz-Centre-Geesthacht,
2University
Institute of Coastal Research, Max-Planck-Str. 1, 21502 Geesthacht, Germany, joerdis.petersen@hzg.de
of Hamburg, Department of Chemistry, Inorganic and Applied Chemistry, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
Introduction
The monitoring along with the assessment of the current status of the marine environment within the context of the EU Water Framework Directive (WFD) or the Marine Strategy Framework Directive (MSFD)
requires new approaches for the accurate and sensitive determination of contaminant levels. Many contaminants show very low concentrations in the water phase. The application of time-integrating sampling
approaches namely passive and active sampling offers interesting perspectives to solve some of the difficulties related with conventional spot sampling. In comparison to conventional spot sampling passive
sampling allows the detection of very low concentrations. Furthermore passive samplers enrich the freely available dissolved fraction of pollutants in water and thus may give also information related to their
bioavailability.
Here we describe first results related to the development of a new approache for the monitoring of selected trace elements in marine waters using passive sampling. Currently the most commonly used passive
sampling devices for time-integrated analysis of metals and metal species are Chemcatcher® -Metal, as well as the so called DGT (diffusive gradients in thin films) devices.
ICP-MS-MS has been used for the first time to analyse passive sampling extracts providing the necessary sensitivity as well as some new possibilities to deal with certain interferences.
Experimental setup and conditions
Chemcatcher-Metal®
Preparation of the Chemcatcher® before exposure
Preparation of the Chemcatcher® after field deployment
Assembling of the
Chemcatcher® body
Receiving phase
Removal of the
receiving phase
Diffusion membrane
3 M HNO3
Receiving phase
Measurement of
the extracts using
ICP-MS-MS
Sampler body
Receiving phase
Conditioning of the Chelating Disk
Field deployment for a
defined exposure time
Extraction of the receiving phase with
30 mL of 3 M HNO3
Soaking of the membrane in 1 % HNO3 overnight
DGT
Preparation of the DGT before exposure
Preparation of DGT after field deployment
ESI SC-4DX Fast Autosampler
Membrane filter
Removal of the
receiving phase
Diffusive gel
Conc. HNO3
Sampler body
Resin gel
Agilent 8800 ICP-MS Triple Quad
Measurement of
the extracts using
ICP-MS-MS
Resin gel
Field deployment for a
defined exposure time
Composition of a commercially available
DGT device
Overnight extraction of the receiving
phase with 1 mL of conc. HNO3
Results
Outlook
Recovery Chemcatcher® for selected trace metals
The Chemcatcher® is suited to
accumulate the selected set of
metals as indicated by the good
recoveries that have been
measured. A recovery of nearly
100% has been found for all the
selected metals.
Next experiments will target the in deep evaluation of external influences on the uptake rate of the samplers
such as flow velocity, temperature and salinity using a flow-through exposure system, which allows to
maintain a constant metal concentration in the water phase during the whole exposure experiment.
Experimental setup for calibration of passive sampler for the accumulation of
metal and metal species
Measurement of time weighted average concentration (cw) of selected trace metals at
the station Cuxhaven
Carousel including passive sampler device
Time weighted average concentrations at different time
points of selected metals in Cuxhaven using
Chemcatcher –Metal
Time weighted average concentrations at different time
points of selected metals in Cuxhaven using DGT
Helmholtz-Zentrum Geesthacht • Max-Planck-Straße 1 • 21502 Geesthacht • Phone +49 (0)4152 87-1843 • Fax +49 (0)4152 87-1875 • joerdis.petersen@hzg.de
References :
(1)Kingston, J; Greenwood R, Mills GA, Morrison, GM and Björklund-Persson, L (2000): Development of a novel passive sampling system for the timed-averaged measurement of a range of organic pollutants in aquatic environments. J Environ Monit 2: 487–495.
(2)Zhang H, Davison W (1995): Performance Characteristics of Diffusion Gradients in Thin Films for the in Situ Measurement of Trace Metals in Aqueous Solution. Anal.Chem.67, 3391-3400.
(3)Vrana B, Mills GA, Dominiak E, Greenwood R (2006): Calibration of the Chemcatcher passive sampler for the monitoring of priority organic pollutants in water. Environ. Poll. 142, 333-343.
Plan for calibration experiments
experiment
time
1
2
3
4
5
6
7
8
9
14 d
14 d
14 d
14 d
14 d
14 d
14 d
14 d
14 d
water temperature water flow
20°C
10°C
5°C
10°C
10°C
10°C
10°C
10°C
10°C
0,5 m/s
0,5 m/s
0,5 m/s
0,25 m/s
0,8 m/s
1 m/s
0,5 m/s
0,5 m/s
0,5 m/s
salinity
pH
0
0
0
0
0
0
12 psu
25 psu
33 psu
8
8
8
8
8
8
8
8
8