Aqueous photochemistry of neonicotinoids unveils a major source of atmospheric reactive nitrogen impacting global climate
Year: 2025
Type: article
Abstract: Neonicotinoid insecticides (NNs), widely deployed in agriculture, are now recognized as pervasive environmental contaminants. This study reveals that the photochemical degradation of nitenpyram (NPM), a prominent NN, in the aqueous phase generates substantial fluxes of gaseous reactive nitrogen species, including nitrous acid (HONO) and nitrogen oxides (NOx = NO + NO 2 ). Reaction pathways, elucidated through aqueous and gas-phase product analysis and density functional theory (DFT) calculations, demonstrate that HONO, NO 2 , and NO arise directly from the excited triplet state of NPM. Global modeling, parameterized by laboratory-derived kinetics, estimates annual emissions of 71.2 Gg N yr −1 (NOx) and 40.7 Gg N yr −1 (HONO) from NPM photodegradation. These emissions elevate boundary-layer concentrations of HONO, ozone (O 3 ), and OH by 0.54%, 0.11%, and 0.20%, respectively, globally. Our findings uncover a significant, yet overlooked, source of reactive nitrogen that perturbs global nitrogen cycling, amplifies atmospheric oxidative capacity, and influences climate dynamics.
Authors: Jiangping Liu, Zhu Ran, Yanan Hu, Dedong He, Can Ye, Keding Lu, Haichao Wang, Shuai Li, Xiao Lu, Jingwei Zhang, Zhijiong Huang, Junyu Zheng, Xinming Wang, Yongming Luo, Sasho Gligorovski
Institutions: Kunming University of Science and Technology, Peking University, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Yunnan University, Jinan University, The Hong Kong University of Science and Technology (Guangzhou), Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Guangdong Technion-Israel Institute of Technology
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $3,590
OpenAlex ID: W4417456093