1. A computer implemented method of generating olfactory cohorts, the computer implemented method comprising: receiving olfactory data from a set of chemical sensors, wherein the olfactory data describes a set of olfactory patterns associated with particles in an air sample; processing the olfactory data, by an olfactory analysis engine, to identify attributes of the particles in the air sample and generate digital olfactory data, wherein the digital olfactory data comprises metadata describing attributes of the particles in the air sample; and generating a set of olfactory cohorts using the attributes in the digital olfactory data.