When visiting an outpatient clinic, there are always mothers of children with congenital hand and foot deformities who ask why her child has this condition. This is a good question, but not an easy one to answer well. The simple answer is genetics, environmental influences, and that’s what’s called a good answer. But when explored more closely, it is not so simple to give an answer. There has always been a clear genetic expression of hand and foot deformities. Some parents will naturally say, “My child’s hands are the same as his brother’s, and so is his father’s, they are all the same. This is obviously a genetic problem. However, there is also a large percentage of children who do not have a history of deformity in their family. Parents may wonder why this child has multiple fingers on his hand when the family is fine. In fact, as hand surgeons, we are asking the same question: why is the incidence of children with hand and foot deformities increasing so rapidly? Ten years ago, our department did a dozen cases of congenital hand and foot deformities a year. Now, I alone do a dozen malformations a month, and the number of children is exploding. To answer this question, we did a survey to try to find out if the parents of the affected children had been exposed to any specific substances before or during pregnancy. Unfortunately, it was difficult for many parents to accurately recall which suspicious substances they had been exposed to at the time. But interestingly, most of the suspicious substances that could be accurately recalled were paints. Either one of the parents was a painter, or they were in a hurry to move into a new home that had just been freshly painted. One couple was even more clearly suspicious of paint because they hadn’t moved anywhere in their home, just the floors had been painted. Because of the lack of good cross-referencing, and the fact that recollection alone is not sufficiently convincing, the results of the survey we obtained will not be published in the end. However, at least this is a relatively obvious hint. Now that the second child is open, I believe more parents will be preparing for a new family member. Hopefully, they will avoid exposure to some toxic and harmful chemicals before and during pregnancy, or some suspicious substances that are now highly suspected, and eventually welcome a healthy and active baby.