Even an Apple charger can damage a Mac. It's far, far more rare since Apple tends to have superior QA and more motivation to make sure the adapter fails over the computer than the average knock off manufacturer.
That being said, there are many good chargers that will work just fine. The main risk is fire from a poorly constructed transformer as opposed to down stream damage to your Mac since the magsafe port delivers between 3 V and 25 V DC it's not a huge amount of power or danger to life or hardware.