Diazinon　is　an　organophosphorus　pesticide　widely　used　in　agriculture　and　household　pest　control,　and　its　use　also　poses　several　environmental　and　health　hazards.　In　this　study,　we　investigated　the　spatial　and　temporal　distribution　of　diazinon　in　Baiyangdian,　evaluated　its　potential　ecological　risk　and　toxicity　to　aquatic　organisms　based　on　RQ　(Risk　quotient)　and　TU　(Toxic　unit)　analysis,　and　assessed　the　potential　effects　of　diazinon　accumulation　on　probiotics　and　pathogens　based　on　statistical　analysis　of　high-throughput　sequencing　data.　The　results　showed　that　diazinon　in　Baiyangdian　posed　a　low　to　moderate　chronic　risk　to　sediment-dwelling　organisms　and　a　low　toxicity　effect　on　aquatic　invertebrates,　which　was　mainly　concentrated　in　October　and　human-intensive　areas.　Meanwhile,　increases　in　sediment　electrical　conductivity　(EC),　amorphous　iron　oxides　content　and　phenol　oxidase　activity　favored　diazinon　accumulation　in　sediments,　whereas　the　opposite　was　the　case　for　sediment　organic　carbon,　β-1,4-glucosidase,　phosphatase,　catalase　and　pH,　suggesting　that　environmental　indicators　play　a　key　role　in　the　behavior　and　distribution　of　diazinon.　In　addition,　diazinon　in　heavily　contaminated　areas　seem　to　inhibit　the　rare　probiotics　(Bifidobacterium　adolescentis　and　Serratia　sp.),　while　promoted　dominant　pathogens　(e.g.,　Burkholderia　cenocepacia),　which　can　lead　to　increased　disease　risk　to　humans　and　ecosystems,　disruption　of　ecological　balance　and　potential　health　problems.　However,　probiotic　Streptomyces　xiamenensis　resist　to　diazinon　would　be　a　potential　degrader　for　diazinon　remove.　In　conclusion,　this　study　unveiled　the　effects　of　diazinon　pollution　on　wetland　ecosystems,　emphasizing　ecological　impacts　and　potential　health　concerns.　In　addition,　the　discovery　of　diazinon　resistant　probiotics　provided　new　insights　into　wetland　ecological　restoration.　©　2024　Elsevier　Ltd