A scrubbing agent includes activated carbon having a spherical shape, a median particle size of 100 to 800 μm, a peak pore diameter of 0.7 nm to 1.2 nm, and a micropore volume of not less than 0.5 cm3/g. The activated carbon satisfies Condition (1). Condition (1): when a sample activated carbon in an amount of one gram is distributed on the surface of 100 g pure water having a temperature of 20° C. and placed in a beaker with a depth of 5 cm； the beaker is placed in a vacuum desiccator； the vacuum desiccator is evacuated with a vacuum pump for 20 minutes； the pure water in the beaker is stirred with a stirring bar at 100 rpm for one minute； and the beaker is left to stand for 30 minutes, not less than 95% by mass of the sample precipitates on the bottom of the beaker.
