Is JSON safe to use as a command line argument or does it need to be sanitized first?

Is the following dangerous?

$ myscript '<somejsoncreatedfromuserdata>'

If so, what can I do to make it not dangerous?

I realize that this can depend on the shell, OS, utility used for making system calls (if being done inside a programming language), etc. However, I'd just like to know what kind of things I should watch out for.