Short answer is no. The board review course comes with access to a question bank and there is a homebrewed app floating around but there is nothing on the level of the major question banks used in medical school. Olson's Poisoning and Drug overdose is a good reference to check on shift and briefly dig a little deeper into an overdose. Goldfrank's is the major regularly updated textbook, they used to make a smaller handbook but I don't think it's been updated in over a decade. There are some good podcasts and a lot of the FOAM websites do a decent job on toxicology. The Tox & the Hound sub-site on EMCrit puts out some great articles.
So plenty to read and listen too but no great question banks.