The photodegradation of lambda-cyhalothrin in various solvents under xenon lamp was studied.At a concentration of 10 mg/L,the half-lives of lambda-cyhalothrin in hexane,methanol,acetonitrile and acetone were 2.95,3.88,5.27 and 50.6 hours,respectively.At a concentration of 20 mg/L,the half-lives of lambda-cyhalothrin in hexane,methanol,acetonitrile and acetone were 2.77,4.32,4.67 and 36.9 hours,respectively.The photolytic rates of lambda-cyhalothrin under xenon lamp in different organic solvents showed the f...