Anthropogenic Pollution Determining Chlorpyrifos residue in apples case study: Damavand orchards Volume 7 (2023) Issue 2, November 2023 2023 12 10 Determining Chlorpyrifos residue in apples case study: Damavand orchards 10.57647/j.jap.2023.0702.14 EN Zahra Haddadnezhad Department of Environment, Damavand branch, Islamic Azad University, Damavand, Iran Omid Mohammadalikhan Persian Blue Rose Tourism Company, Tehran, Iran Shahrzad Khoramnejadian Department of Environment, Damavand branch, Islamic Azad University, Damavand, Iran 0000-0002-9637-9988 Journal Article 2023 12 10 This study was conducted with the purpose of measuring the remaining of Chlorpyrifos insecticide in apples produced in Ahmadabad region of Damavand at the beginning of crop spraying and after its currency period over two periods of the second and third crop spraying in September and October, 2016 and also June, 2017. Samples were collected from three selected stations during September and October, 2016 and also June, 2017. Afterwards, there were some laboratory stages to measure the concentration chlorpyrifos in each sample by means of GC-MASS. According to the calculations made by SPSS software, chlorpyrifos with an average of 1.6917 has a higher level than EPA, ISIRI, CODEX and EFSA standards. Also, in the tests of September and October, chlorpyrifos in all stations has values lower than the EFSA CODEX standard, but in station 1 it is higher than the EPA and ISIRI standards; other stations have values lower than all standards. During the calculations made by SPSS software, it shows that chlorpyrifos with an average of 0.123 has a lower level than CODEX and EFSA standards, but it has a higher level than EPA and ISIRI standards.