Editing Blood alcohol content (section)

=== Direct measurement ===
Blood samples for BAC analysis are typically obtained by taking a venous blood sample from the arm. A variety of methods exist for determining blood-alcohol concentration in a blood sample.<ref name="Dubowski">{{cite journal |last1=Dubowski |first1=Kurt M. |title=Alcohol Determination in the Clinical Laboratory |journal=American Journal of Clinical Pathology |date=1 November 1980 |volume=74 |issue=5 |pages=747–750 |doi=10.1093/ajcp/74.5.747 |pmid=7446484 |url=https://www.researchgate.net/publication/15751585}}</ref> Forensic laboratories typically use [[Headspace gas chromatography for dissolved gas measurement|headspace-gas chromatography]] combined with mass spectrometry or flame ionization detection,<ref>{{cite journal |last1=Zamengo |first1=Luca |last2=Tedeschi |first2=Gianpaola |last3=Frison |first3=Giampietro |last4=Griffoni |first4=Carlo |last5=Ponzin |first5=Diego |last6=Jones |first6=Alan Wayne |title=Inter-laboratory proficiency results of blood alcohol determinations at clinical and forensic laboratories in Italy |journal=Forensic Science International |date=1 February 2019 |volume=295 |pages=213–218 |doi=10.1016/j.forsciint.2018.12.018 |pmid=30611561 |s2cid=58591654 |issn=0379-0738}}</ref> as this method is accurate and efficient.<ref name="Dubowski"/> Hospitals typically use [[enzyme multiplied immunoassay technique|enzyme multiplied immunoassay]], which measures the co-enzyme [[NADH]]. This method is more subject to error but may be performed rapidly in parallel with other blood sample measurements.<ref>{{cite web |title=Hospital Blood Alcohol Lab Results: Are They Forensically Reliable? |url=https://www.new-jersey-dui-defense.com/hospital-blood-alcohol-lab-results-are-they-forensically-reliable.aspx |website=Law Offices of Christopher L. Baxter |date=30 April 2020}}</ref>

In Germany, BAC is determined by measuring the serum level and then converting to whole blood by dividing by the factor 1.236. This calculation underestimates BAC by 4% to 10% compared to other methods.<ref>{{cite journal |last1=Jones |first1=Alan Wayne |title=Concentration units used to report blood- and breath-alcohol concentration for legal purposes differ between countries which is important to consider when blood/breath ratios of alcohol are compared and contrasted |journal=Journal of Forensic Sciences |date=22 March 2024 |volume=69 |issue=4 |pages=1473–1480 |doi=10.1111/1556-4029.15511|pmid=38520069 }}</ref>