Who - a company, a government, or even an individual - paid for a research study? How much were the researchers paid to conduct the study in question? Were their methods or findings influenced by the concerns of their funding body?
Can you put a cash value on a human life? How much should a civilised society be prepared to spend to save a life? What damages should be paid if someone is injured? Should other forms of life, such as apes or trees or a whole landscape, be valued equally?
When does the financial cost of a science project make it not worth the benefits that the knowledge gained would give us? If gaining the knowledge requires great risk to the health or wellbeing of a person or place, how much risk is too much?