Most parent's have heard the risk of nitrates in root vegetable foods, particularly carrots, for their little sprouts. These concerns even go as far as to suggest that commercially produced baby food carrots are somehow "better" for your sprouts than the homemade version... I have always wrestled with this because that just didn't make since to me. Thanks to an article posted my Today I Ate a Rainbow! my concerns have subsided and I can confidently give my sprouts homemade carrots without the worry of nitrates. Here's the article by Dr. Greene, a well respected pediatric MD and great "eco" kid's doctor!
Also, check out Dr. Greene's book, Feeding Baby Green, which is a wonderful resource for any parent!