Unless you know the source of the mulch I'd err on the side of caution and not eat the tomatoes.  Some wood mulches may use construction wood and/or pallets and other wood sources which might have been treated with chemicals or if the mulch is colored the colorant might contain harmful chemicals.  Check the bag the mulch came in.  Plain pine mulch would be OK but compost, shredded leaves or straw would be better.
More info:
https://www.canr.msu.edu/news/select_the_right_vegetable_garden_mulch
https://www.canr.msu.edu/news/mulch_for_the_vegetable_garden
https://hortnews.extension.iastate.edu/faq/what-materials-would-be-good-mulch-vegetable-garden
https://www.goodhousekeeping.com/home/gardening/a20706549/how-to-mulch-your-garden/
https://www.gardeningknowhow.com/garden-how-to/mulch/dyed-mulch-in-gardens.htm
https://extension.uga.edu/publications/detail.html?number=C984