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The assessment of residue, absorption, conduction, and degradation of agricultural organosilicon surfactants in the environment is hindered by the lack of information on active ingredients and corresponding quantitative standards for organosilicon spray adjuvants. The spray adjuvant 'Jiexiaoli,' a primary organosilicon spray agent in China, was identified as hydroxy (polyethylene) propyl‐heptamethyl trisiloxane (TSS‐H) with 3–15 ethoxy (EO) groups. Purification of TSS‐H was achieved through semi‐preparative separation using high‐performance liquid chromatography (HPLC), resulting in TSS‐H purity exceeding 96%. An accurate residual detection method for nine oligomers (4–12 EO) of TSS‐H in rice roots, stems, leaves, and culture solution samples was developed using HPLC tandem high‐resolution mass spectrometry (HPLC‐HRMS). Recoveries for nine oligomers of TSS‐H in the four matrices ranged from 80.22% to 104.01%. Foliar application experiments demonstrated that TSS‐H did not transfer from the upper to the lower parts of the rice plant. The half‐lives of each oligomer (4–12 EO) in leaves were less than 3.21 days. Root application experiments revealed a root concentration factor (RCF) ranging from 0.20 to 0.56, a biological enrichment factor (BCF) ranging from 0.36 to 0.68, a transpiration factor (TSCF) ranging from 0.069 to 0.086, and a transport factor (TF) ranging from 0.08 to 0.43. These results indicated that TSS‐H could be absorbed by rice roots and conducted to the above‐ground parts of rice plants. This study fills the data gap in the environmental risk and food safety assessment of agricultural silicone spray adjuvants. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Citrus leaf miners are a common pest harming citrus production and quality during citrus planting. During the citrus plant's growth phase, bisultap formulation was frequently used to boost yield and produce fruit of high quality. However, research on citrus's dietary risk assessment for bisultap residues, dissipation and residues is lacking. RESULTS: Liquid chromatography‐tandem mass spectrometry was used to develop an accurate and sensitive analytical method for derivatizing bisultap into nereistoxin in whole fruit, pulp and peel. At various levels of addition, the mean recovery of bisultap ranged from 84.64% to 111.09% with a reasonable relative RSD (< 20%). The half‐lives in Guangxi and Guizhou were 3.96 and 6.03 days, respectively. After 14–21 days of bisultap application, total residues (bisultap and its metabolite nereistoxin) in the whole fruit were from < 0.02 to 0.228 mg kg−1 in the four experiment sites. Total residue (bisultap and nereistoxin, expressed by bisultap) in whole fruit was approximately 1.05–7.23 times that of pulp. The washing process with tap water removed 85.71% to 98.78% of the bisultap residue in the whole fruit. Bisultap's risk assessment value in citrus was in the range 0.16–1.28%. CONCLUSION: In the whole citrus fruit, bisultap degrades rapidly. Bisultap residues primarily accumulate on citrus peels, and so washing and peeling citrus may effectively remove bisultap residues. For various age groups, the chronic dietary risk of bisultap was acceptable. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]