sentences:  Because they fall into these two categories, extensive opportunities for complex interactions and varied sites of action as well as multiple molecular targets are open for consideration.Changing dose ranges tend to result in varying phenotypes and timing of exposure, gender, and gender predisposition introduce even more levels of complexity in how these substances effect the human body.Because the mechanisms behind the different effects of obesogens are so complex and not well understood, the extent to which they play in the current obesity epidemic may be greater than once thought.