We have been using a mixture of dried pasta and pulses for our sand tray which the children really enjoy using. Very similar qualities to liquids, great texture etc. So far we've had no problems but someone felt that possible allergy issues. I've seen lots of places using this mixture as well as rice so I assumed that so far these alternatives have not been banned. Are they considered safe (apart from the potential for eating them etc as with most materials and objects)? I been Googling and so far no mention of allergy issues.