A backpack alone isn't heavy -- but pile 5 thick schoolbooks into it and it becomes a possible health hazard for kids.
HealthDay reported on the potential risks of backpacks, which actually resulted in 7,300 emergency room visits in 2006.
According to Paula Kramer, from the University of the Sciences occupational therapy department in Philadelphia, backpacks that are worn incorrectly can "strain muscles and joints and cause serious back pain."
Kramer's tips for a safer backpack? The size should fit the child wearing it, as smaller children should carry smaller bags. Padded shoulder straps are also something to look out for -- and making sure they are fitted snugly against the body is important as well. Another option is the triangular sling-style bag, which goes over only one shoulder and across the body. A backpack should also weigh less that 10 to 15 percent of the child's body weight.