If found this interesting FAQ in the link EZ provided:
I forgot to rinse out the equipment. Will my beer/wine be OK?
All equipment should be rinsed before use. Anything left in a fermenting vessel will affect the taste. Any active bacteria feft may kill the yeast.
So, they don't mention that is poisonous, but the taste and yeast may be affected. Two or three drops might not have such a big impact. I would continue the process and taste it before bottling.
According to this link, you will probably be fine: http://www.thehomebrewforum.co.uk/showthread.php?t=25587