In order to assess the danger you need to monitor realtime exposure to radioactive particles. There is no measurements here. It seems the data exists in Europe but not publicly accessible which is a shame.

The Tchernobyl accident released a lot of radioactivity in the air.

The soil contamination is twofold :

- spotty : some rocks that blew thru the explosion highly contaminated some spots.

- distributed : the plume contaminated the soil with material of different half-lifes.

The problem here is that trees are recycling organic matter that was tainted by radioactivity and so, if they burn they release it in floating materials.

We cannot infer something meaningful from the plume's direction as the atmosphere has high-flowing air currents in upper atmosphere that redistribute the pollution.

Only a raise of radioactivity in realtime measurements will tell. I'm sure the effect can be seen in Europe currently, yet no one wants to scare people so information is hidden.