The internal consistency of the 'analyst' diffusive sampler - A long-term field test

A recently developed diffusive sampler, intended for use in long-term ambient measurements of volatile aromatic hydrocarbons, has been tested to determine the upper limits of its Sampling capacity A test has been performed over 12-month period to evaluate these limits in terms of its 'internal consistency (i.e. checking if the sum of the amounts of a given pollutant, determined over shorter consecutive periods, matches the amount determined from a single long-term exposure). Results demonstrate that the uptake rate of the device, in a real (indoor) atmosphere, is constant for approximately 8 months for benzene and for approximately 10 months for toluene. The upper limit for higher homologous species was not reached after exposure for a year to typical ambient concentrations. This means the device can be successfully used for several months, thereby enabling low-cost determinations of ambient BTX concentrations.