Core Viewpoint - The implementation of two new national ecological environment standards, HJ 1413-2025 and HJ 1414-2025, on August 1, 2025, will standardize the measurement of specific polysaccharides in particulate matter, enhancing the scientific and precise analysis of air quality in China [1][9]. Group 1: Ion Chromatography Method (HJ 1413-2025) - The HJ 1413-2025 standard specifies the technical requirements for measuring left-handed dextran, mannan, and galactan in particulate matter using ion chromatography [2]. - The method involves ultrasonic extraction of the sample, purification through organic and heavy metal purification columns, followed by separation using an ion chromatography column and detection via amperometric detector [2]. - Detection limits for left-handed dextran, mannan, and galactan are 0.09 mg, 0.08 mg, and 0.08 mg respectively, with measurement limits of 0.36 mg, 0.32 mg, and 0.32 mg [3]. Group 2: Derivatization/Gas Chromatography-Mass Spectrometry Method (HJ 1414-2025) - The HJ 1414-2025 standard utilizes derivatization-GC-MS technology for ultra-trace detection of the same polysaccharides in particulate matter [5]. - The method includes ultrasonic extraction or pressurized fluid extraction, followed by concentration and derivatization with methylsilyl reagent, and detection using GC-MS based on retention time and characteristic ions [5]. - Detection limits for left-handed dextran, mannan, and galactan are significantly lower, at 0.02 mg, 0.01 mg, and 0.007 mg respectively, showcasing a reduction of 1-2 orders of magnitude compared to ion chromatography [7]. Group 3: Technical Collaboration and Environmental Impact - The two standards will enhance monitoring capabilities and support precise air pollution prevention efforts by providing critical data for biomass combustion source analysis [9]. - The unified detection methods will standardize data quality across regions, improving comparability of monitoring results [9]. - The implementation of these standards is expected to contribute to the development of targeted emission reduction policies, aiding in the fight against air pollution [9].

Core Viewpoint - The Ministry of Ecology and Environment has approved four national ecological environment standards aimed at regulating the analysis of particulate matter sources in the air, effective from August 1, 2025 [2][3]. Group 1: Standards Overview - The first standard, "Technical Specification for Open Source Dust Sampling of Ambient Air Particulate Matter" (HJ 1411-2025), is the first release and outlines the technical requirements for sampling open source dust, including soil, road, construction, stockpile, and mixed dust [4]. - The second standard, "Technical Specification for Automatic Weighing of Particulate Matter Filter Membranes" (HJ 1412-2025), also marks its first release and specifies the basic requirements and operational norms for using automatic weighing systems for filter membranes [6][8]. - The third standard, "Ion Chromatography Method for Determining Levoglucosan, Mannan, and Galactomannan in Particulate Matter" (HJ 1413-2025), introduces a method for measuring specific sugars in particulate matter, with detection limits detailed for various sample volumes [10][12][13]. - The fourth standard, "Derivatization/Gas Chromatography-Mass Spectrometry Method for Determining Levoglucosan, Mannan, and Galactomannan in Particulate Matter" (HJ 1414-2025), specifies a method for measuring the same sugars using gas chromatography-mass spectrometry, with detection limits provided for different sample conditions [15][18][20].