Abstract: Objective To develop a detection method for simultaneous determination of eight herbicides（including 2,4-D,fosamine,aminomethylphosphonic acid,glufosinate,ethephon,glyphosate,glyphosine,and bentazone） and plant growth regulators in drinking water by ion chromatography,which has a simple pretreatment process and only requires common reagents. Methods The water sample is sequentially filtered through a 0.2 μm microporous membrane and a Ba/Ag/H cartridge before being introduced into the system. The effective separation is achieved on an IonPac AS19 chromatographic column using a 2-60 mmol/L potassium hydroxide gradient elution program. After the background signal is reduced by a suppressor,the analytes are detected by a conductivity detector. Results The eight analytes exhibit excellent linearity within the concentration range of 0.002-0.200 mg/L（0.005-0.200mg/L）,with correlation coefficients（r） all >0.999. The method demonstrates detection limits ranging 0.000 2-0.003 6 mg/L and quantification limits ranging 0.000 6-0.011 1 mg/L. At low,medium,and high spiked concentration levels,the recovery rates range from 94.3% to 108.6%,with relative standard deviations（RSD） between 0.592% and 4.425%（n=7）. Compared with the national standard method,the detection results showed no statistically significant difference（P>0.05）. Conclusion This method is characterized by its simplicity of operation,effective separation,and satisfactory accuracy,precision and sensitivity,making it suitable for routine monitoring of drinking water.

Key words: Ion chromatography, Drinking water, Herbicide, Plant growth regulators, Simultaneous determination