A method and near field communications (NFC) system for sensing at least one of an environmental condition or a composition of media in a proximity of the NFC system are provided. In the method and system, a first antenna irradiates an electromagnetic field during a sensor mode. A second antenna detects the electromagnetic field and outputs a voltage representative of the detected electromagnetic field. An NFC controller receives a signal representative of the voltage. The NFC controller determines at least one of the environmental condition or the composition of media based on an association stored in memory between the voltage and the at least one of the environmental condition or the composition of media.