Reducing the Environmental Risk of Chlorpyrifos Application through Appropriate Agricultural Management: Evidence from Carbon-14 Tracking

Abstract

Chlorpyrifos (CPF) is one of the most critical insecticides in the world. However, many countries are gradually banning its use due to its reported hazardous impacts on humans. This study explored the possibility of reducing the environmental risk of CPF through appropriate agricultural management practices. Results showed that the environmental risk of CPF is lower under drainage conditions because there is more mineralization and less bound residues (BRs) than under submerged conditions. Bioaugmentation significantly enhanced the CPF mineralization and inhibited the formation of CPF-BRs. Biochar adsorbed CPF and thus reduced its bioavailability, but it could not completely eliminate the toxicity of CPF. In addition, bioaugmentation did not significantly affect the native microbial community of CPF-contaminated soil, suggesting its safety in reducing the environmental risk of CPF. The study indicated that the environmental risk of CPF could be reduced by appropriate agricultural management such as water management, bioaugmentation, soil biochar amendment, and selecting suitable soil types.

Bioaugmentation of Atrazine-Contaminated Soil With Paenarthrobacter sp. Strain AT-5 and Its Effect on the Soil Microbiome

“…Some studies have demonstrated that the persistence of inoculum in the environment is a key factor of bioaugmentation ( Chi et al, 2013 ; Yang et al, 2021 ). Our previous study showed the inoculated exogenous degrading strain could not survive well in soil, resulting in the decrease of chlorpyrifos mineralization rate ( Jia et al, 2021a ). By qRT-PCR and 16S rRNA-amplicon sequencing, we found that the inoculated strain AT-5 survived well in the soil and remained relatively stable during the incubation period of 14 days, which ensured its remediation efficiency for atrazine-contaminated soils.…”

“…By qRT-PCR and 16S rRNA-amplicon sequencing, we found that the inoculated strain AT-5 survived well in the soil and remained relatively stable during the incubation period of 14 days, which ensured its remediation efficiency for atrazine-contaminated soils. In addition, bioremediation is often subject to environmental constraints, such as soil type ( Jia et al, 2021a ). However, strain AT-5 showed good remediation effects in three different soils collected from Jining, Langfang, and Xuzhou, China ( Supplementary Figures S3 , S4 ), indicating that strain AT-5 has great potentials for the remediation of atrazine-contaminated different types of soil.…”

“…DNA Extraction, Sequencing, and Quantitative Real-Time PCR Soil total DNA was extracted from the soil sample (0.5 g, dry weight) using a Fast DNA SPIN Kit for Soil (MP Biomedicals, United States). The V4 region of the 16S rRNA gene was amplified using the primer set 515F and 806R as described previously (Jia et al, 2021a). The amplified 16S rRNA genes were sequenced by Biozeron Biological Technology Co. Ltd. (Shanghai, China) on an Illumina HiSeq 2,500 platform.…”

Mixed-Solvent Sorption and Moisture-Regime-Dependent Degradation of Chlorpyrifos in Selected Tropical Soils

“…Degradation experiments were conducted on nine soil samples obtained from Kakira, Lugazi, and Kalangala, utilizing a slightly modified procedure based on the work of Awasthi and Prakash (1997) and Jia et al (2021). Each soil sample was divided into two groups: unsterilized and sterilized soils.…”

“…By the methods outlined by Awasthi and Prakash (1997) and Jia et al (2021), three soils, namely K7, Lira, and Kitoke, were employed in this study with minor adjustments. Triplicate samples weighing 5 grams each of sterilized and unsterilized soils were carefully placed in 50 mL polycarbonate centrifuge tubes.…”