WeLLLL, there are always multiple risks of participating in an ICO. The first is that the project might not go well and the coins that are delivered in exchange for money will not worth anything. The biggest problems with the ICO is , that your money can be stoled.

The security of the crypto currency is not correct and someone manages to steal all the money. The most recent case is that of DAO, where more than $150 million were stolen, money that investors lost.

Another risk is that these type of operations are not regulated, and are outside the conventional financial system. This does not appeal to governments for several reasons. On the one hand because they lose control of money and taxes; on the other, because these ICOs can be used for criminal activities.