Action 2: Laboratory analytical techniques

Present activities & status

The analytical laboratory sections of INRaSTES possess complementary skills to the field-measurement sections, since these two topics are highly interrelated. An equally large number of personnel are involved in analytical laboratory techniques, who receive constant training in new protocols and analysis techniques. The INRaSTES laboratory infrastructure features several rare and unique facilities on a regional and National level for the analysis of Environmental samples and characterization of air pollution. Present infrastructure includes: gas and liquid chromatography, spectrometry, low total-beta counting and absorption systems for gas and aerosol characterization, thermal/optical system for particulate EC/OC quantification, instrumentation for the determination of radon and radon daughters in air and water, in-situ instruments for detection of ionizing radiation, aerosol spectrometer calibration system, polydisperse aerosol generation system, as well as controlled environmental chambers.

The Institute is also involved in the design and development of aerosol instrumentation and provides technology transfer services for Local Authorities and Industry in the field and in line with EU directives for environmental protection and compliance with limit values legislation, including Calibration and validation of aerosol/particulate matter measurement infrastructure according to EN12341 standard for fine and coarse aerosol mass fraction measurement (PM10 PM2.5 PM1).

 

Research Vision and Associated Actions in EnTeC

The analytical laboratory facilities will be disaggregated into five complementary analytical facilities, but with distinct role and functionality. The output of the analytical laboratories will be placed to the INRaSTES repository (Action 5) and also be used for scientific dissemination.

The Gas Sampling Facility

The main functionality will be to build a central flask sample facility for gases to condition flasks for use in the field, and will direct the sample flow for the diverse analyses. A standardised glass flask design (1L, two tap, Kel-F seals) will be combined with a flask treatment facility to condition the flask for use in the field. It will be designed to work together with the sampling set ups of the field stations and the diverse analytical facilities in the laboratories.

The Gas Analysis Facility

This facility will measure trace gases in unattended operation for high-precision concentration measurements of CO2, CO, CH4, N2O, SF6, and H2. A system for Greenhouse Gas analysis will be configured using a GC-FID/ECD with EPC coupled with pneumatic control modules and automated port valves. It will consist of two parallel channels with simultaneous detection of methane, carbon dioxide and nitrous oxide in air. As far as the sampling system is concerned, canisters will be used for the air sample collection. The sampling to the system will be through gas sampling valve. Autodilution system will be used for the calibration.

The Chemical Aerosol Analysis Laboratory

Over the years INRaSTES laboratories have developed extensive knowledge for chemical analysis and characterization of fine and ultra-fine particles that have been awarded accreditation according to EN 17025. The chemical speciation of aerosol on filter samples from the urban and backgrounds stations will be analysed for the Organic and Elemental Carbon fraction OC/EC. The instrument is used to analyze aerosol particles collected on quartz-fiber filters for both organic carbon and elemental carbon (OC/EC).

Complementary to the organic fraction the sources of particles can be identified by measurements of their chemical composition by ion chromatography (DIONEX IC1100). Salts such as NaCl, CaCO3, Ca2NO3, (NH4)2SO4, and NH4NO3 comprise a large fraction of aerosol particles. The various salts are often found as solutions in particles, where the salts dissociate and form cations and anions. This existing technique will be also expanded to a real time measurement by means of a PILS (particle-into-Liquid-sampler) GC/MS.

X-ray Fluorescence spectrometry has been described by the EPA Compendium Method IO-3.3 as a an appropriate chemical analysis technique that provides quantification of 44 elements in the ng/cm2 range in PM2.5 and PM10 airborne particulate matter deposited on Teflon air filters. Instrumental XRF developments utilizing high energy excitation and polarizing optical path already introduced in commercial instruments allow full compliance of XRF sensitivity limits with respect to European Union current limits values required for urban environment; Air Quality Daughter Directive (2004/107/EC), Reported sensitivities attained with a commercial high energy, polarizing geometry energy dispersive XRF spectrometer also fulfil the requirements given in EN14902 for As, Ni and Pb. The purchase of a high throughoutput commercial XRF energy dispersive spectrometer would allow:

• Monitoring of airborne particulate matter (APM) composition in a non destructive manner for almost half of periodic table elements in one run.
 
• Characterrization of APM samples in daily basis due to automated procedure.

Determination of Polycyclic hydrocarbons in particles could significantly contribute to the determination of their origin. Samples are collected in filters using a high volume pump and through a chemical procedure the extract is analyzed for the determination of PAHs in a GC-MS chromatographic system.

The physical aerosol analysis laboratory

Aerosol tracers relevant to transport pattern in the troposphere and residence time of air masses can be derived from gamma spectrometry analysis on aerosol filters combined with Rn222 measurements from the field stations for radioactive aerosol tracers relevant to Boundary layer Dynamics and processes such as Be7, Pb210 and Po210. The laboratory will be also upgraded with an extra Particle generation, Electrostatic Classifier and Condensation Particle Counter (CPC) setup in order to establish a permanent aerosol size calibration facility so that field aerosol instruments can periodically be calibrated.