National Physical Laboratory

Heavy Metals Network

This Network measures ambient levels of arsenic, cadmium, chromium, cobalt, copper, iron, manganese, nickel, lead, platinum, selenium, vanadium, zinc, and mercury, in particulate matter, at 25 sites around the UK. Vapour phase mercury is also measured at 13 sites. Accurately measured concentrations of the most toxic metals: arsenic, cadmium, nickel, mercury and lead are requirements of the new EC Air Quality Directive and the Fourth Air Quality Daughter Directives. Sites are predominantly located downwind of large metals processing facilities and in centres of population.

Particulate samples are taken using Partisol 2000 instruments (fitted with PM10 heads), for a period of one week, onto filters. Vapour-phase mercury sampling takes place by pumping air at a constant rate through gold-coated silica absorption tubes.

Analysis for particulate-phase metals is carried out at NPL by ICP-MS. Analysis of vapour-phase mercury samples takes place at NPL by thermal desorption and atomic fluorescence. Both procedures are UKAS-accredited. More information on the operation of the Network is described in the publications listed below:

  • Interlaboratory comparison exercise for the determination of As, Cd, Ni and Pb in PM10 in Europe
    Gerboles, M; Brown, R J C; et al
    Atmospheric Environment, 2011, 45, 3488-3499
  • Comparison of estimated annual emissions and measured annual ambient concentrations of metals in the United Kingdom 1980-2007
    Brown, R J C
    Journal of Environmental Monitoring, 2010, 12, 665-671
  • Twenty-five years of nationwide ambient metals measurement in the United Kingdom: concentration levels and trends
    Brown, R J C, Yardley, R E, Muhunthan, D, Butterfield, D M, Williams, M, Woods, P T, Brown, A S, Goddard S L
    Environmental Monitoring and Assessment, 2008, 142, (1-3), 127-140
  • Accurate calibration of mercury vapour measurements
    Brown, R J C, Brown, A S
    Analyst, 2008, 133, 1611-1618
  • Establishing SI traceability for measurements of mercury vapour
    Brown, A S, Brown, R J C, Corns, W T, Stockwell, P B
    Analyst, 2008, 133, (6), 946 - 953
  • On the Optimum Sampling Time for the Measurement of Pollutants in Ambient Air
    Brown, R J C, Hood, D, Brown, A S
    Journal of Automated Methods and Management in Chemistry, 2008, Volume 2008, Article ID 814715, 6 pages
  • A practical uncertainty budget for ambient mercury vapour measurement
    Brown, R J C, Brown, A S, Yardley, R E, Corns, W T, Stockwell, P B
    Atmospheric Environment, 2008, 42, (10), 2504–2517
UK Heavy Metals Monitoring Network

Location of sites on the UK Heavy Metals Monitoring Network
(image courtesy of Defra)
Last Updated: 24 Nov 2011
Created: 17 Apr 2007


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