By now most people are aware of the links between smoking and lung cancer, but they probably don’t know that cigarettes may contribute to breast cancer too.

Since August, fourth-year biology student Samantha Richardson has been feeding lab mice a mixture of corn oil, sesame oil and benzopyrene – just one of 50 carcinogenic chemicals found in cigarette smoke – and monitoring the effect on the animals’ mammary glands.

“The lungs are really the interface for blood supply in your body, so these chemicals are capable of getting out of the lungs and circulating through your body and getting into all kinds of organs,” explains biology professor Lisa Porter, who is supervising Richardson’s research.

“These chemicals can do the same things that they do in the lungs,” said Dr. Porter, who spoke last night at Trash the Ash, an event in the Schulich Windsor Health Lecture Series. “They can get to the cells, and all of these carcinogens bind to the DNA in your cells and damage them. As your cell that gets damaged makes new cells, it continues to pass on that damage, and that’s really how cancer initiates.”

Richardson, who is completing a double major in psychology, is trying to understand the effects of low doses of benzopyrene on the mice over long periods of time. Some of the mice get the chemical mixture, while the control group simply gets the oil. She studies the mammary glands of the female mice throughout the stages of giving birth, lactation and then return to their “virgin” state – a process known as “involution” – to track changes the chemical has on the natural process of development.

“Surprisingly, this isn’t a question that’s been asked before,” said Porter, “whether different stages of development make people more susceptible to the cancers caused by cigarette smoke.”

Richardson said she will continue collecting data throughout the rest of the academic year and present her results in a thesis next spring. She said she loves doing the research and thinks it may contribute to an existing body of knowledge on the subject, or perhaps even get published on its own in an academic journal.

“It’s really fascinating research,” said Richardson, who is considering the possibility of pursuing a master’s degree.

Porter, who is trying to convince her to do just that, says she can see the project expanding to learn more about what other kinds of diseases to which the chemicals may contribute.

Watch a video on Richardson's work: