Xinbin Feng

• Professor, PhD
• Professor (Full) at Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002

The Multi-Compartment Hg (mercury) Modeling and Analysis Project (MCHgMAP) is an international multimodel research initiative intended to simulate and analyze the geospatial distributions and temporal trends of environmental Hg to inform effectiveness evaluations of two multilateral environmental agreements (MEAs): the Minamata Convention on Mercur...

Elevated methylmercury (MeHg) exposure poses significant risks to bird health, behavior, and reproduction. Still, the risk of MeHg exposure to forest birds, accounting for over 80 % of the world’s bird species, is poorly understood. This study combines Hg isotopes and video analysis, aiming to assess MeHg exposure risks to a forest riverine songbir...

Despite concerns about methylmercury (MeHg) contamination in rice, the sources and transformation mechanisms of MeHg within paddy field water, the primary source of MeHg in rice, remain unclear. Determination of the isotopic composition of MeHg in paddy water is crucial to clarify these processes. However, there is a lack of sampling and analytical...

Methylmercury (MeHg), accumulated in rice grains, is highly toxic for humans. Its production is largely driven by microbial methylation in paddy soils; however, dissolved organic matter (DOM) is a critical component of the soil biogeochemistry process, yet its interactions with microorganisms involved in MeHg production remain poorly understood. He...

Vegetative development in regions where glaciers retreated due to global warming forces mercury (Hg) cycle in the cryosphere. This study depicts the fate of Hg in a glacier-retreated chronosequence over the last 250 years recorded by signals of stable Hg isotopes. Results show that the Hg storage in surface soil increases by 3.2 times over 250 year...

PM2.5‐bound antimony (Sb) may threaten human health and sustainable development, necessitating accurate source identification for its effective control. This study pioneered the application of Sb isotope signatures to trace PM2.5‐bound Sb sources, presenting the first isotopic fingerprints of Sb in urban PM2.5. We selected two mega‐cities with cont...

Mercury is a volatile heavy element with no known biological function. It is present in trace amounts (on average, ~80 ppb) but is not geochemically well-blended in the Earth's crust. As a result, it sometimes occurs in extremely high concentrations (up to a few %) in certain locations. It is found along tectonic plate faults in deposits of sulfide...

Oceanic emission of gaseous elemental mercury (Hg⁰ or GEM) is an important source for atmospheric mercury (Hg), but existing estimates of global gross oceanic Hg⁰ emissions are highly variable (800–7,220 Mg yr⁻¹). This study measured atmospheric GEM concentrations and isotopic compositions at two coastal sites in Terengganu, Malaysia, a region that...

Atmospheric elemental mercury (Hg0) assimilation by foliage contributes prevalently to the global atmospheric Hg0 sink in forests. Today, little is known about the mechanisms of foliar Hg accumulation and how climate factors and tree physiology interact to impact it. Here, we examined meteorological factors, foliar physiological traits, and Hg accu...

Wetlands in the Qinghai-Tibet Plateau (QTP) are a unique and fragile ecosystem undergoing rapid changes. We show two unique patterns of mercury (Hg, a global pollutant) accumulation in wetland sediments. One is the ‘Surface Peak’ in monsoon-controlled regions, and the other is the ‘Subsurface Peak’ in westerly-controlled regions. The former is attr...

Transport of exogenous anthropogenic mercury (Hg) is an important source of Hg pollution in the Tibetan Plateau (TP) and its downstream water ecosystems, but the origins and contributions of Hg sources remain uncertain. Here, we investigate the concentrations and isotopic compositions of gaseous elemental mercury (GEM) at four rural sites in the TP...

Karst terrains provide drinking water for about 25% of the people on our planet, particularly in the southwest of China. Pollutants such as arsenic (As) in the soil can infiltrate groundwater through sinkholes and bedrock fractures in karst terrains. Despite this, the underlying mechanisms responsible for As release from karst soils under redox cha...

In the past decade, China has motivated proactive emission control measures that have successfully reduced emissions of many air pollutants. For atmospheric mercury, which is a globally transported neurotoxin, much less is known about the long-term changes in its concentrations and anthropogenic emissions in China. In this study, over a decade of c...

Isotope data of key pollutants are needed for source apportionment analysis in natural ecosystems. Isotope data for cadmium (Cd), a rare and dispersed but toxic element, are very limited mainly due to its low contents in the natural environment. In this study, for samples with low Cd content but high organic matter content, a dry ashing pre-treatme...

The effect of seafloor cold seeps on the biogeochemical cycling of mercury (Hg) remains enigmatic. Here we demonstrate substantial enrichments of mercury and methylmercury, along with the presence of microbes capable of metabolizing mercury in sediments of the Haima cold seep, South China Sea, by analyzing mercury and methylmercury concentrations,...

Methylmercury (MeHg), accumulated in rice grain, is highly toxic for human. Its production is largely driven by microbial methylation in paddy soils; however, dissolved organic matter (DOM) represents a hotspot for soil biogeochemistry, resulting in MeHg production, remain poorly understood. Here, we conducted hgcA gene sequencing and genome-resolv...

Mercury (Hg) is a globally distributed heavy metal. Here, we study Hg concentration and isotopic composition to understand the status of Hg pollution and its sources in Pakistan’s paddy soil. The collected paddy soils (n = 500) across the country have an average THg concentration of 22.30 ± 21.74 ng/g. This low mean concentration suggests Hg pollut...

The Multi-Compartment Hg (mercury) Modeling and Analysis Project (MCHgMAP) is an international multi-model research initiative intended to simulate and analyze the geospatial distributions and temporal trends of environmental Hg to inform the effectiveness evaluations of two multilateral environmental agreements (MEAs): the Minamata Convention on M...

Geothermal fields emit remarkable amounts of mercury (Hg) to the environment. To address the source, fate and geochemical cycling of Hg in geothermal fields, we investigated Hg concentrations and isotopic compositions of hot spring water and fumarole gases from Rehai and Dagejia in SW‐China. Elevated Hg concentrations in fumarole gases (10.0–167 ng...

Knowledge gaps in mercury (Hg) biomagnification in forest birds, especially in the most species-rich tropical and subtropical forests, limit our understanding of the ecological risks of Hg deposition to forest birds. This study aimed to quantify Hg bioaccumulation and transfer in the food chains of forest birds in a subtropical montane forest using...

Selenium (Se) serves as a natural detoxifier for the typical toxic heavy metal of mercury (Hg) and the interactions between Se and Hg have attracted considerable scholarly attention in the field of Se and Hg. However, there is currently a lack of systematic summaries and discussions of Se-Hg interactions in soil-plant systems. This study summarizes...

The re-emission and subsurface migration of legacy mercury (Hg) are not well understood due to limited knowledge of the driving processes. To investigate these processes at a decommissioned chlor-alkali plant, we used mercury stable isotopes and chemical speciation analysis. The isotopic composition of volatilized Hg(0) was lighter compared to the...

Knowledge gaps of mercury (Hg) biogeochemical processes in the tropical rainforest limit our understanding of the global Hg mass budget. In this study, we applied Hg stable isotope tracing techniques to quantitatively understand the Hg fate and transport during the waterflows in a tropical rainforest including open-field precipitation, throughfall,...

The karst forest is one of the extremely sensitive and fragile ecosystems in southwest China, where the biogeochemical cycling of mercury (Hg) is largely unknown. In this study, we investigated the litterfall deposition, accumulation, and soil migration of Hg in an evergreen-deciduous broadleaf karst forest using high-resolution sampling and stable...

Understanding mercury (Hg) complexation with soil organic matter is important in assessing atmospheric Hg accumulation and sequestration processes in forest ecosystems. Separating soil organic matter into particulate organic matter (POM) and mineral-associated organic matter (MAOM) can help in the understanding of Hg dynamics and cycling due to the...

Methylmercury (MeHg) produced in rice paddies is the main source of MeHg accumulation in rice, resulting in high risk of MeHg exposure to humans and wildlife. Net MeHg production is affected by Hg(II) reduction and MeHg demethylation, but it remains unclear to what extent these processes influence net MeHg production, as well as the role of the mic...

The production of methylmercury (MeHg) in flooded paddy fields determines its accumulation in rice grains; this, in turn, results in MeHg exposure risks for not only rice-eating humans but also wildlife. Nitrogen (N) fertilizers have been widely applied in rice cultivation fields to supply essential nutrients. However, the effects of N fertilizer a...

Selenium (Se) elevates the antioxidant ability of rice against cadmium (Cd) stress, but previous studies only focused on the variation in antioxidant enzymes or nonenzymatic substances induced by Se under Cd stress and ignored the relationships between different antioxidant parameters during the interaction. Here, hydroponic experiments with rice w...

Foliage uptake of atmospheric elemental mercury (Hg0) and subsequent translocation by the phloem is the main pathway for Hg accumulation in tree rings. Tree rings have been used as the emerging natural archive to directly reconstruct centennial trends of atmospheric Hg0 level. The tree-ring Hg records in remote regions have successfully reconstruct...

Measuring the isotopic composition of Hg in natural waters is challenging due to the ultratrace level of aqueous Hg (ng L-1). At least 5 ng of Hg mass is required for Hg isotopic analysis. Given the low Hg concentration in natural waters, a large volume of water (>10 L) is typically needed. The conventional grab sampling method is time-consuming an...

Methylmercury (MeHg) is a microbially produced neurotoxin derived from inorganic mercury (Hg), which accumulation in rice represents a major health concern to humans. However, the microbial control of MeHg dynamics in the environment remains elusive. Here, leveraging three rice paddy fields with distinct concentrations of Hg (Total Hg (THg): 0.21−5...

Significant knowledge gaps exist regarding the emission of elemental mercury (Hg0) from the tropical forest floor, which limit our understanding of the Hg mass budget in forest ecosystems. In this study, biogeochemical processes of Hg0 deposition to and evasion from soil in a Chinese tropical rainforest were investigated using Hg stable isotopic te...

In this study, exchange fluxes and Hg isotope fractionation during water-atmosphere Hg(0) exchange were investigated at three lakes in China. Water-atmosphere exchange was overall characterized by net Hg(0) emissions, with lake-specific mean exchange fluxes ranging from 0.9 to 1.8 ng m-2 h-1, which produced negative δ202Hg (mean: -1.61 to -0.03‰) a...

A lack of knowledge about antimony (Sb) isotope fractionation mechanisms in key geochemical processes has limited its environmental applications as a tracer. Naturally widespread iron (Fe) (oxyhydr)oxides play a key role in Sb migration due to strong adsorption, but the behavior and mechanisms of Sb isotopic fractionation on Fe (oxyhydr)oxides are...

Anthropogenic activities and climate change have significantly increased mercury (Hg) levels in seawater. However, the processes and sources of Hg in differing marine compartments (e.g. estuary, marine continental shelf (MCS) or pelagic area) have not been well studied, which makes it difficult to understand Hg cycling in marine ecosystems. To addr...

China is the largest contributor to the global total anthropogenic mercury (Hg) emissions. However, the trend in anthropogenic Hg emissions in recent years in China has not been effectively evaluated due to the lack of long‐term atmospheric Hg observations. This study documents the changes in atmospheric gaseous elemental mercury (GEM) concentratio...

Methylmercury (MeHg) contamination in rice via paddy soils is an emerging global environmental issue. An understanding of mercury (Hg) transformation processes in paddy soils is urgently needed in order to control Hg contamination of human food and related health impacts. Sulfur (S)-regulated Hg transformation is one important process that controls...

Mercury (Hg) was reported to accumulate in rice grains, and, together with the selenium (Se) was found in rice, the co-exposure of Hg-Se via rice consumption may present significant health effects to human. This research collected rice samples containing high Hg:high Se and high Se:low Hg concentrations from high Hg and high Se background areas. Th...

The colonization and expansion of plants on land is considered one of the most profound ecological revolutions, yet the precise timing remains controversial. Because land vegetation can enhance weathering intensity and affect terrigenous input to the ocean, changes in terrestrial plant biomass with distinct negative Δ199Hg and Δ200Hg signatures may...

Litterfall, typically referring to needles/leaves, may stand for >50% of the total mercury (Hg) deposition in forest ecosystems. By detailed categorisation, we reveal for the first time that the contributions through lichens and fine litter, together 9.98 μg Hg m-2 yr-1, could be as high as that in needle litter (9.96 μg m-2 yr-1) to the annual tot...

Long-range transport and atmospheric deposition of gaseous mercury (Hg0) result in significant accumulation of Hg in the Qinghai-Tibetan Plateau (QTP). However, there are significant knowledge gaps in understanding the spatial distribution and source contribution of Hg in the surface soil of the QTP and factors influencing Hg accumulation. In this...

Anthropogenic mercury (Hg) emissions have increased significantly since the Industrial Revolution, resulting in severe health impacts to humans. The consumptions of fish and rice were primary human methylmercury (MeHg) exposure pathways in Asia. However, the lifecycle from anthropogenic Hg emissions to human MeHg exposure is not fully understood. I...

Indian monsoon circulation is the primary driver of the long‐range transboundary mercury (Hg) pollution from South Asia to the Himalayas and Tibet Plateau region, yet the northward extent of this transport remains unknown. In this study, a strong δ²⁰²Hg signature overlapping was found between Lake Gokyo and Indian anthropogenic sources, which is an...

Mine waste (MW) in historical mercury (Hg) mining areas continuously emits Hg into local environment, including aquatic ecosystems. Tracing Hg migration process from MW and determining its relative contribution to Hg pollution is critical for understanding the environmental impact of MW remediation. In this study, we combined data of Hg concentrati...

Rice paddies provide optimum conditions for Hg methylation, and paddy soil is a hot spot for Hg methylation and the predominant source of methylmercury (MeHg) accumulated in rice grains. The role of dissolved organic matter (DOM) in controlling Hg bioavailability and methylation in rice paddy systems remains unclear. Paddy soils from eight various...

Aquatic systems play a key role in the global antimony (Sb) cycle, but studies on the isotopic ratio of Sb in freshwater are very rare due to the low Sb...

Mercury (Hg) is a toxic metal that can be released from natural and anthropogenic processes. Gaseous elemental Hg is the main form of Hg in the atmosphere with a long residence time, allowing its long-range transport and deposition at a global scale. The deposited Hg can be transformed into methylmercuy (MeHg), which bioaccumulates and biomagnifies...

Cardamine violifolia belongs to the Brassicaceae family and is a selenium (Se) hyperaccumulator found in Enshi, China. In this study, C. violifolia was found to accumulate mercury (Hg) in its roots and aboveground parts at concentrations up to 6000 μg/g. In the seedling and mature stages, the bioaccumulation factors (BAFS) of Hg reached 1.8-223, wh...

Mercury (Hg) is an important element in seafloor cold seeps that might govern methane emission. However, so far, the knowledge of biogeochemical Hg cycle in it remains poorly understood. In this study, Hg geochemical characteristics and microorganisms involved in Hg biogeochemical cycling were examined in three (active, inactive seep vs reference)...

Uptake of atmospheric elemental mercury via foliage is thought to be the dominant pathway of mercury accumulation in terrestrial ecosystems, including those in the Arctic permafrost regions. Whether a similar process operates in alpine permafrost regions remains unknown. Here we report mercury concentrations and stable isotopic signatures in a larg...