Suppression of Chlorantraniliprole Sorption on Biochar in Soil-Biochar Systems.

The sorption behavior of chlorantraniliprole (CAP) by biochar and effect of soil extracts on sorptivity in soil-biochar systems were examined. The results showed that biochar amendment could enhance the sorption of CAP in soils. The values of K F increased significantly when the soils were amended with 0.5 % BC850, which were from 1.54 to 196.5. The indigenous sorptivity of biochar was suppressed after it was applied to the soils. The degree of biochar sorptivity attenuation in different soil-biochar systems varied with the properties of soil water soluble matters. Sorption of CAP by biochar from the five soil extracts was found to be lower than that from a CaCl2 solution. The calculated K d values at C w of 0.01 mg kg(-1) for biochar sorption of CAP from CaCl2 solution were 21.4-26.6 times of that from soil extracts. Aging of biochar in soil extract reduced CAP sorption by up to 85 %.

Persistence and dissipation of chlorpyrifos in Brassica chinensis, lettuce, celery, asparagus lettuce, eggplant, and pepper in a greenhouse.

The residue behavior of chlorpyrifos, which is one of the extensively used insecticides all around the world, in six vegetable crops was assessed under greenhouse conditions. Each of the vegetables was subjected to a foliar treatment with chlorpyrifos. Two analytical methods were developed using gas chromatography equipped with a micro-ECD detector (LOQ = 0.05 mg kg(-1)) and liquid chromatography with a tandem mass spectrometry (LOQ = 0.01 mg kg(-1)). The initial foliar deposited concentration of chlorpyrifos (mg kg(-1)) on the six vegetables followed the increasing order of brassica chinensis