Martin Tsz-Ki Tsui

I study mercury cycling in inland habitats including stream and river, lake, wetland and forest. Mercury is a highly toxic metal, but it is present in all ecosystem types due to long-range atmospheric transport and deposition. I use concentration and speciation analyses to quantify the levels of mercury present in different types of environmental matrices including water, sediment, soil and biota. I also use a newly developed technique that can measure stable isotope ratios of mercury to better understand the sources and transformation of mercury in the environment. By combining concentration/speciation and isotopic analyses, I have recently shown that it is feasible to decipher the sources of methylmercury (bioavailable form of mercury) in predatory wildlife including insects, fish, and birds, which presents a totally new approach of resolving complexities of mercury bioaccumulation as well as food web dynamics. In addition, I am interested in studying the toxicity and cycling of other pollutants such as heavy metals, pesticides and organic chemicals in the environment.

There are 9 included publications by Martin Tsz-Ki Tsui :

TitleDateViewsBrief Description
Controls of Methylmercury Bioaccumulation in Forest Floor Food Webs 2019 333 Compared to the extensive research on aquatic ecosystems, very little is known about the sources and trophic transfer of methylmercury (MeHg) in terrestrial ecosystems. In this study, we examine energy flow and trophic structure using stable carbon (...
Feasibility of Sijunzi Tang (Chinese medicine) to enhance protein disulfide isomerase activities for reactivating malate dehydrogenase deactivated by polycyclic aromatic hydrocarbons 2018 25 The objective of this research is to investigate the enzymatic activities between protein disulfide isomerase (PDI) found in animals and plants and the properties found in a commonly used Chinese medicine called Sijunzi Tang. During the investigation...
Methylmercury and methane production potentials in North Carolina Piedmont stream sediments 2017 34 Methylated mercury (MeHg) can be produced by all microbes possessing the genes hgcA and hgcB, which can include sulfate-reducing bacteria (SRB), iron-reducing bacteria (FeRB), methane-producing archaea (MPA), and other anaerobic microbes. These micro...
Microbial Pathways of Mercury Methylation During Litter Decomposition 2019 52 Tree foliage sequesters gaseous elemental mercury (Hg) through stomatal uptake, when the foliage senesces and falls into the water, Hg from leaf litter can be released into the water and/or microbially methylated into a highly toxic form, methylmercu...
New Insights on Ecosystem Mercury Cycling Revealed by Stable Isotopes of Mercury in Water Flowing from a Headwater Peatland Catchment 2018 41 Stable isotope compositions of mercury (Hg) were measured in the outlet stream and in soil cores at different landscape positions in a 9.7-ha boreal upland-peatland catchment. An acidic permanganate/persulfate digestion procedure was validated for wa...
Origin, Reactivity, and Bioavailability of Mercury in Wildfire Ash 2018 57 Wildfires are expected to become more frequent and intensive at the global scale due to climate change. Many studies have focused on the loss of mercury (Hg) from burned forests; however, little is known about the origins, concentration, reactivity, ...
Photomicrobial Visible Light-Induced Magnetic Mass Independent Fractionation of Mercury in a Marine Microalga 2018 51 Methylmercury (MeHg), a highly neurotoxic substance, accumulates in aquatic food webs, and is enriched in odd isotopes (i.e., 199Hg and 201Hg), purportedly as a result of abiotic photodegradation in surface waters. Here, we highlight the potential ro...
Understanding sources of methylmercury in songbirds with stable mercury isotopes: Challenges and future directions 2018 65 Mercury (Hg) stable isotope analysis is an emerging technique that has contributed to a better understanding of many aspects of the biogeochemical cycling of Hg in the environment. However, no study has yet evaluated its usefulness in elucidating the...
Variation in Terrestrial and Aquatic Sources of Methylmercury in Stream Predators as Revealed by Stable Mercury Isotopes 2014 929 Mercury (Hg) is widely distributed in the environment, and its organic form, methylmercury (MeHg), can extensively bioaccumulate and biomagnify in aquatic and terrestrial food webs. Concentrations of MeHg in organisms are highly variable, and the sou...