BAL (Blood Alcohol Level) refers to ethanol level. BAL is indirectly obtained by multiplying the osmolar gap by 4.6 (4.6 converts from ethanol in mmol/L to ethanol in mg/dL). Notice that this gap might be due to many other substances including --but not limited to-- methanol, ehtylene glycol, etc. See for more about Osmolar gap and substances levels.
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