The csv file "Aldehydes_Raw_Data.csv" contains the aldehyde data. The
file has a header line and contains the following 5 columns:

ID: 	     Type of e-liquid or aerosol sample
No:	     Sample number
Below MDL:   Logical variable that indicates whether the measured
             concentration if below the MDL
Aldehyde:    Name of the measured aldehyde
conc:	     Measured concentration in units of ng/g

Metals_Raw_Data.csv The csv file "Metals_Raw_Data.csv" contains the
metals data. The file has a header line and contains the following 5
columns:

ID: 	     Type of e-liquid or aerosol sample
No:	     Sample number
Below MDL:   Logical variable that indicates whether the measured
             concentration if below the MDL
Metal:       Name of the measured metal
conc:	     Measured concentration in units of ng/g
