Gravitational waves (GWs) encode important information about the mass of the source. For binary black holes (BBHs), the templates that are used to retrieve the masses normally are developed under the assumption of a vacuum environment. However, theories suggest that astrophysical BBHs could form in the vicinity of supermassive black holes or in gas-rich environments. In this talk, I will highlight the effects of the aforementioned environments on the chirp signal of stellar-mass BBHs. I will show that neglecting these environmental effects would lead to a miscalculation of the true mass and distance of the LIGO/Virgo sources, as well as a possible misinterpretation of the underlying astrophysics.