Ultra-trace determination of mercury in river waters after online UV digestion of humic matter

Abstract

A fully automated online ultraviolet (UV) digestion method for subsequent mercury (Hg) quantification in humic matter containing river waters is reported. The new developed flow injection analysis system (FIAS) consists basically of a UV lamp, a meander-form quartz glass reaction tube for online irradiation of the sample, and a nano-gold collector for preconcentration of dissolved mercury species. The FIAS is coupled to an atomic fluorescence spectrometer (AFS) for Hg detection. The optimized procedure allows accurate mercury quantification in water samples with up to 15 mg CL(-1) as dissolved organic carbon by addition of only 1% (v/v) of hydrogen peroxide solution and online UV irradiation for 6 min. Addition of strong oxidants and any other reagents is avoided due to the use of the catalytic active nano-gold collector. Here, preconcentration of Hg species, release of mercury as Hg(0), and AFS measurement are performed without addition of any reagents. Hence, the proposed approach offers significant advantages over existing methods. Analytical figures of merit showed the good performance of the developed method: The limit of quantification was found to be as low as 0.14 ng Hg L(-1). The linear working range is from 0.1 to 200 ng Hg L(-1) and relative standard deviation is <6.0% (n = 9). The system was successfully validated by comparison of the mercury concentrations found in model and real water samples obtained by the reference method EPA 1631 and the proposed method. Furthermore, application to six real river waters confirmed the feasibility of the proposed approach.

Analysis of Sources and Sinks of Mercury in the Urban Water Cycle of Frankfurt am Main, Germany

“…The monitoring program of the Hessian Agency for the Environment and Geology (HLUG) on THg concentrations in hessian rivers provided highest concentrations of 38 ng/L with an average value of 8 ng/L (n = 51) in river Main at the sampling point Bischofsheim (12 km downstream from M7) [14]. From other German rivers (Isar and Danube) THg concentrations ranging from 0.41 to 0.64 ng/L have been reported [15]. In comparison to these data, Figure 3c.…”

Global Meta‐Analysis on the Relationship Between Mercury and Dissolved Organic Carbon in Freshwater Environments

“…In total, 108 studies were excluded through that screening process. A total of 44 studies were kept from this search (Bergman & Bump, 2014;Berndt et al, 2016;Berndt & Bavin, 2012;Braaten et al, 2014;Bravo et al, 2017;Brazeau et al, 2013;Burns et al, 2012Burns et al, , 2013Burns et al, , 2014Burton et al, 2013;Chaves-Ulloa et al, 2016;de Wit et al, 2014;Demers et al, 2013;Denkenberger et al, 2014;Dranguet et al, 2017;Eckley et al, 2015;Eklöf et al, 2013;Ekstrom et al, 2016;Fagnani et al, 2012;Gerson & Driscoll, 2016;Girard et al, 2016;Guedron et al, 2014;Hamelin et al, 2015;Haverstock et al, 2012;Houben et al, 2016;Jeremiason et al, 2016;Leopold et al, 2012;Loftin et al, 2012;Luo et al, 2014;MacMillan et al, 2015;Moreno et al, 2016;Navratil et al, 2015;Noh et al, 2016;Oswald & Branfireun, 2014;Painter et al, 2015;Picado & Bengtsson, 2012;Poste et al, 2015;Pyhtila et al, 2012;Riscassi et al, 2016;Sherman & Blum, 2013;…”

Low picomolar, instrument-free visual detection of mercury and silver ions using low-cost programmable nanoprobes

“…This could be circumvented by either nitrification or a UV digestion procedure prior to detection. 48,49 …”