There are the Frosted Pop Tarts and the Unfrosted Pop Tarts. The unfrosted kind is a type of toaster pastry that is definitely vegan. As for the frosted ones, it has whey, gelatin and glaze which may contain some animal products.
It is better to limit your intake of pop tarts, in general. This toaster pastry is processed food and it is laden in sugar too. You know what that means, right?