Move? 

:Dioxin (disambiguation) → Dioxin —
 Dioxin (disambiguation) →  — it has a number of meanings so it needs "dioxin" as prim dab page. —   (talk) - 
This was moved in the opposite direction just 2 weeks ago. Perhaps you should talk with the original mover to see why he thinks there's a primary topic. If you can't come to an agreement, then file a full move request here.