ADDITIONAL: If you're scrubbing a figure that's been in something toxic, wear rubber/latex gloves.
If you find any areas that the toothbrush won't reach (Areas like beneath the chin, or around a fine detail) then use a fine-tipped tool to pry the paint loose.
You CAN use a toothpick, although they are quite fragile and may not have a fine enough tip. Using a sculpting tool or a needle will work, but you risk scratching your figure.
A decent article - would've liked to see a photo halfway through, showing the paint dissolved.