In some Chinese shoe factories, winter is glue poisoning season. With the windows shut, benzene, and other toxic volatile chemicals in glue are more likely to make people sick. Even with adequate ventilation, spending too much time glueing shoes can lead to leukemia and other diseases over the long-term. That’s why a Dutch designer is introducing shoes that are made without glue at all. The added benefit: “It should be normal to replace your sole or upper, like replacing a tire on your bike.”