This is a summary of how your data is processed if you sign up for the newsletter, or buy from my store. I don't manage the data personally as it's not my area of expertise, but instead use two trusted and secure services which are described below. The bottom line is that the minimum amount of data is held, to fulfil only the purposes you provided it for, only as long as is needed. Your data is kept securely, and will not be sold to any other parties.
If you choose to sign up for my infrequent newsletter; I need to store your email address to get in touch about artibiotics news, articles, or products. I use Mailchimp for this service, who are a global leader in managing mailing lists securely, and running email campaigns. They keep individuals like me right, for example by offering unsubscribe options in every email, and holding these lists securely, only for as long as you wish to remain subscribed.
My website (including online store) is built on the Squarespace platform. They securely hold information about purchases made, so that I can fulfil orders, e.g. who bought what and when, and manage taxes.
Remember, you can unsubscribe at any time via the link in every email.