Dynamics In Paddy And Adsorption In Soil Of Triazphos

The residue dynamics of triazphos were studied in paddy,water and soil.The residue dynamics accumulation and ultimately residue of triazphos were detected by HPLC.The limit of detection of HPLC was 1.39×10¹⁰g,The limit of quantification of triazphos by HPLC was 0.005mg·kg^-1,the recovery of the method was 80-110.0%;When high dosage 480a.i.g.hm^-2 20%triazphos EC was applied in paddy and soil,Two years' field test showed that residue of triazphos in paddy plant were 7.15-10.56mg·kg^-1original respectively,the half-life of triazphos was 1.5-18.3h.The residue of triazphos in soil were 0.28-0.30 mg·kg^-1 original respectively,the half-life of triazphos was 4.2-6.6d.The residue of triazphos in water were 0.45-0.47mg·kg^-1,the half-life of triazphos was 0.4-0.5d in water.The degradation procedure oftriazphos scribed by first-order kinetics equation, C=C₀e^-kt.In plant of paddy,the dynamic equation in 2006 and in 2007 were C=5.1676e^-0.3407tand C=5.1676e^-0.3407t.In soil,the dynamic equation in 2006 and in 2007 were C=0.2066e^-0.0588t and C=0.1915e^-0.0626t.In water,the dynamic equation in 2006 and in 2007 were C=0.1737e^-0.602t and C=0.1737e^-0.602t.The degradation rate was more than 90%in plants of paddy and water after 5 days,the results showed that triazphos is easy to degrade in plant of paddy and soil.The final residual concentration oftriazphos in plant of paddy,soil,paddy and rice was determined.Two years' field test showed that,when 20%480a.i.g.hm^-2triazphos EC was applied in paddy;the final residue of triazphos in plant of paddy,soil,paddy and rice fell below detectable limit.But when 20%480a.i.g·hm^-2 triazphos EC was applied in paddy,the final residue of triazphos in plant of paddy,soil,paddy and rice can be detected a little.The adsorption of triazphos by soil was studied by equilibrium method.Four different types of soil were used in the study triazphos solutions(20mL) of different density were added to soil(lg) and were shaken at 25℃,A HPLC method was carried out to detect the triazphos in water after 24 hours.The result showed that the adsorption oftriazphos was mainly influenced by organic carbon content.