Organophosphate acaricides have extensive use in livestock to manage Ticks and Tick borne diseases, environmental pollution arise due intensive use. The study was aimed at detection and quantification of Chlorpyrifos in soil, dip wash, spray race residues, milk and milk products from Kilifi, Nakuru and Kajiado Counties. A baseline survey was conducted using questionnaire, formal interview and personal observation to collect data on use and type of acaricides. Soil, dip wash, spray race residues, milk and milk products from farmers, analyzed and quantified for presence of Chlorpyrifos using HPLC. Data obtained was analyzed using SPSS. The 7 spray race and dip wash, 9 milk and milk products, 6 soil and 5 water samples were Chlorpyrifos positive. Milk and milk products concentration ranged 1.000?0.242 mgL-1 - 2.854?0.149 mgL-1 (Nakuru), 1.930±0.106 mgL-1 - 2.017±0.049 mgL-1 (Kilifi), 0.915?0.048 mgL-1 - 8.556?0.549 mgL-1 (soil), 0.888?0.180 mgL-1 - 1.870?0.0243 mgL-1 (water), 0.918?0.217 mgL-1 - 3.282?0.140 mgL-1 (dip wash and spray race). It can be concluded that Chlorpyrifos accumulated beyond WHO acceptable limit of 0 to 0.01 mgL-1 body weight. Concentration was higher in Nakuru than Kilifi and Kajiado Counties. Surveillance, monitoring and regulation on use of Chlorpyrifos in manufacturing acaricides are highly recommended.

Keywords: Chlorpyrifos; HPLC; Acaricides; Accumulation; Milk