Comparison of ethanol concentration in saliva and blood from police controlled persons

The salivary ethanol concentration correlates very well with the serum level (r = 0.98) in samples which are obtained almost simultaneously from persons undergoing a traffic control. If ethanol was referred to the aqueous compartment the saliva/plasma ratio was about 0.85; this ratio was about 11% less than the theoretical one and remained constant over the entire concentration range applied. Saliva could be taken together with breath samples from traffic participants which are controlled for ethanol consumption. The advantage of saliva in favour of blood is that it can be obtained nearly simultaneously with the breath sample without the intervention of a physician and does not hurt the person under suspicion. Furthermore saliva is suited for the voluntary surveillance of former alcoholics who are willing to prove that they are able to live abstinently.