Present Knowledge and Future Perspectives of Atmospheric Emission Inventories of Toxic Trace Elements: A Critical Review

Abstract

Toxic trace elements (TEs) can pose serious risks to ecosystems and human health. However, a comprehensive understanding of atmospheric emission inventories for several concerning TEs has not yet been developed. In this study, we systematically reviewed the status and progress of existing research in developing atmospheric emission inventories of TEs focusing on global, regional, and sectoral scales. Multiple studies have strengthened our understanding of the global emission of TEs, despite attention being mainly focused on Hg and source classification in different studies showing large discrepancies. In contrast to those of developed countries and regions, the officially published emission inventory is still lacking in developing countries, despite the fact that studies on evaluating the emissions of TEs on a national scale or one specific source category have been numerous in recent years. Additionally, emissions of TEs emitted from waste incineration and traffic-related sources have produced growing concern with worldwide rapid urbanization. Although several studies attempt to estimate the emissions of TEs based on PM emissions and its source-specific chemical profiles, the emission factor approach is still the universal method. We call for more extensive and in-depth studies to establish a precise localization national emission inventory of TEs based on adequate field measurements and comprehensive investigation to reduce uncertainty.

Analysis of the Coupled Assessment of Ecosystem Health and Its Spatial and Temporal Evolution in Fujian China

“…Due to the complexity of ecosystems, a single index often does not provide a comprehensive and effective assessment and description of ecosystems [13]. Remote sensing technology has the advantages of wide-scale monitoring, periodicity and real-time assessment, and is widely used for ecosystem health degree evaluation, while remote sensing-based ecological index methods use principal component analysis coupled with NDVI [14,15], Wetness Index (WET) [16], dryness (the Normalized Difference Based built and Impervious Surface Index, NDBSI) [17,18] and heat (Land Surface Temperature, LST) four ecological indicators, which can systematically evaluate the health of regional ecosystems [19,20]. The biggest problem in the Anthropocene is how to deal with the coupling of "society-economy-environment", and society, economy and environment have become an inseparable research whole.…”

Variable Valence State of Trace Elements Regulating Toxic Potencies of Inorganic Particulate Matter

“…3−5 The toxic potency of particulate TEs relies on the chemical composition elements, as well as their oxidation states. 6,7 Owing to the spatiotemporal heterogeneity of PM 2.5 in the atmosphere and the discrepancies in their toxicity, 8,9 exposure to particulate TEs could cause unequal health risks across different regions. 10−12 Although the toxic assessment of each TE treated as a single substance has been intensively investigated via various methods, 10−14 limited knowledge on the valence state of particulate TEs and their associated toxicities makes it challenging to accurately evaluate their toxic potencies.…”

“…Exposure to airborne particulate matter (PM), which contains various toxic components, is widely recognized to be associated with a variety of adverse health impacts. , Inorganic toxic constituents bonded in PM with a diameter of less than 2.5 μm (PM 2.5 ) have already been revealed to be dominated by trace elements (TEs). − The toxic potency of particulate TEs relies on the chemical composition elements, as well as their oxidation states. , Owing to the spatiotemporal heterogeneity of PM 2.5 in the atmosphere and the discrepancies in their toxicity, , exposure to particulate TEs could cause unequal health risks across different regions. − Although the toxic assessment of each TE treated as a single substance has been intensively investigated via various methods, − limited knowledge on the valence state of particulate TEs and their associated toxicities makes it challenging to accurately evaluate their toxic potencies.…”

Improved Anthropogenic Mercury Emission Inventories for China from 1980 to 2020: Toward More Accurate Effectiveness Evaluation for the Minamata Convention

“…To reduce global Hg pollution, the Minamata Convention on Mercury has entered into force with five point source categories addressed, including coal-fired power plants (CFPPs), coal-fired industrial boilers (CFIBs), non-ferrous metal smelters (NFMSs), cement clinker plants (CCPs), and waste incineration facilities (WIFs). A series of air pollution control devices (APCDs) have been installed in various industries to reduce NO x , SO 2 , and particulate matter (PM) in recent years, leading to co-benefits of atmospheric Hg emission reduction. − As the largest anthropogenic Hg emitter, China shall establish accurate inventories of Hg emissions from key sources and evaluate the effectiveness of Hg emission control.…”