Environment/Exposome-wide association studies (EWAS) is an analytic approach, similar to Genome-wide association studies (GWAS), which is to identify the assoociation between exposures and disease/disease related traits (Patel. 2014). There are several advantages to perform EWAS: 1) This approach allows to search the environmental data at large scale and adjust them accordingly; 2) Results from EWAS are all the probed associatiions.