[3] Harkup was inspired to write A Is For Arsenic because of her interest in Christie's mystery novels as a teenager, particularly those involving Hercule Poirot.

As a science communicator, she noticed that young students were generally interested in "anything dangerous or disgusting", which further inspired the work.

[6] She subsequently wrote Making the Monster: The Science Behind Mary Shelley’s Frankenstein in 2018.

[7] In 2020, Harkup published Death by Shakespeare: Snakebites, Stabbings and Broken Hearts.

[8] The book dealt with the portrayal of death in William Shakespeare's plays and the scientific understanding that went into his work.