In animal studies, they have been shown to cause cancer, liver toxicity andThe list is set up as parallel items that attach to "cause": "... cause cancer, (cause) liver toxicity ..." But the third item in the list has its own verb, meaning it doesn't attach right: "... to cause cancer, (cause) liver toxicity and (cause) interfere with growth ..."
interfere with growth and development.
Best solution is to break up the list form:
In animal studies, they have been shown to cause cancer and liver toxicity and(Side note: Sorry I've been absent lately. Crazy, crazy schedule stuff.)
to interfere with growth and development.