To cause cancer it would be exposure to chemotherapy treatment drugs or the fluids of people who have been treated with those drugs.
For example, pee from people who have been treated with chemotherapy drugs contains (eventually) the full dose of those drugs in slightly different forms that are still toxic.
Yup, that or maybe exposure to medical chemicals in amounts that are not intended.
To cause cancer it would be exposure to chemotherapy treatment drugs or the fluids of people who have been treated with those drugs.
For example, pee from people who have been treated with chemotherapy drugs contains (eventually) the full dose of those drugs in slightly different forms that are still toxic.