Graphite paste electrodes were modified by addn. of various amts. (up to 100% by mass) of corm powdered activated C and used for detection of m-CIC6H4OH in aq. soln. (0.5 mmol/L) in presence of Na2SO4 (0.1 mol/L) by differential pulse voltammetry. The detection limit for the paste electrode without activated C was 0.048 mmol/L, while for the electrode with optimum compn. (60% addn. of activated C) was 0.006 mmol/L.