What is the fine-grained topic of the following text: Acting Det Ch Supt Ray Howard, head of Intelligence and Specialist Operations, said: "I am pleased that Thames Valley Police will now be able to take action to prevent the sale and distribution of these substances, which can be highly addictive and have many associated risks, including negative consequences to a person's mental health. Only return the topic.
Prevention of sale and distribution of addictive substances by Thames Valley Police