Tritium is not pleasant though, but veeeeeeeeery far from anything that could do real harm: https://en.wikipedia.org/wiki/Tritium#Health_risks (you'd need to leak a lot of it continuously)
In the same way, a fusion plasma doesn't hold that much energy because of the extremely low density (4×10^-6 that of air). An explosion (a runaway/chain reaction) is also not possible: the reactor must continuously supplied with fuel or the fusion reactions will stop in a matter of seconds.
There are situations which could result in significant damage to the reactor components, but still not a public safety concern. Distruptions are events in which the plasma confinement is lost and a large amount of heat is released that could damage all components that face the plasma, but reactors are designed to withstand this.
Another drawback, if you like, are runaway electrons, which are populations of relativistic particles that become unbound and penetrare the vacuum vessel for several mm. Again, this is not a particular issue from a safety point of view, but they can do a lot of damage: if they hit a magnetic coil and cause a loss of the superconductivity state, the coil can heat very rapidily (due to the huge current that goes through it) and potentially melt. Replacing such a coil could cost years of maintenance, for this reason reactors are build with many fallback systems.
Costing hundreds or thousands of times as much as solar + storage is a more serious problem. Since it won't be built, that is a theoretical problem. But the project can absorb an unlimited amount of money first.