Ultratrace Portable Mercury Vapor Analyzer Gardis-7
Although, gold amalgamation and cold vapor atomic absorption spectrometry (CVAAS) method has been well-introduced and features sufficient sensitivity for the atmospheric background - level gaseous mercury monitoring, sometimes it is suspected for positive interference, and at certain point this may be the case.
Actually, some of the VOCs (volatile organic compounds) contained in ambient air may be adsorbed at the surface of the gold trap, then thermally desorbed and thus cause some UV light absorption at the 253.7 nm mercury spectral feature due to the broad absorption bands of the organic molecules, and this UV light absorption may interfere (overlap) with the small absorption signal of the background-level atmospheric mercury vapor.
The above mentioned drawbacks can be the case with many of the „gold amalgamation + CVAAS“ systems but not with the newest generation mercury analyzer Gardis-7.
Our proprietary gold trap system (EU patent pending, invention novelty confirmed), allows to avoid interference and we have tested it in the atmosphere under hard conditions, including simulated tropical forest in a closed room space, featuring high humidity and high concentration of VOCs, at the orangery of University of Vytautas Magnus in Kaunas, to make sure to obtain ideally clean thermograms of the atmospheric background level gaseous elemental mercury under these unfavorable conditions.