IntoxiGraph
Version 1.0
This program simulates alcohol absorption and metabolism and displays a graph of estimated Blood Alcohol Content (BAC) over time. The simulation includes multiple drinks and food items, the type and size of each drink, and the time when each drink or food item was started.
Table of Contents
Features
This program features:
- A sophisticated simulation that produces a graph of your estimated BAC for up to 16 hours before and 12 hours after the current time. The simulation uses a physics based multi-compartment model that includes the user's height, weight, and gender, and accounts for food as well as alcohol consumption.
- The ability to add multiple drinks and food items.
- The ability to add drinks and food items at a particular time, including in the past or future.
- A database of over 500 common beers, cocktails, wine types, and liquors.
- The ability to quickly and easily specify generic substitutes when the database doesn't have a particular drink.
- The ability to store data and profiles for up to 4 different people.
This program does not access the network, including for this documentation.
Safety
Do not drink and drive. There is no "safe" BAC for driving. Your risk of being involved in an accident while driving increases with any alcohol consumption. Nor is there a safe level legally; in many places (including the USA), you can still be convicted of DUI even if your BAC is under the limit.
Disclaimer
This software is for entertainment purposes only. Though the model in this software is sophisticated and may be accurate on average, it is inaccurate in some cases. It is not possible for this software to accurately calculate every individual's BAC, nor is BAC a good indicator of a person's fitness to perform any dangerous activity such as operating a motor vehicle. It is not possible for any software to accurately calculate BAC for every individual and scenario given the information that IntoxiGraph uses. In addition there may be errors in the code and data that significantly affect the results of the simulation. See the section Accuracy below for more information.
Instructions
Getting Started
- On the Profiles page, select a profile and enter information about yourself.
- On the Graph page, you can add and remove drinks and food items and the graph will show a blue line to indicate your simulated BAC.
Using The Graph Page
- The graph shows the simulated BAC curve and the food and drinks that are used as input to the simulation. The vertical axis is BAC (grams of ethanol per 100 ml of blood) and the horizontal axis is time.
- The current time is indicated on the graph by a vertical gray dashed line.
- The point where the current time intersects the blue BAC curve shows your current simulated BAC.
- The time cursor marks a particular point in time so that you can add an item at that time rather than at the current time. The time cursor is shown on the graph as a vertical blue-gray dashed line. You can set the time cursor by touching the graph in an area where there are no food or drink items. To clear the time cursor you can touch the graph title, vertical axis, or horizontal axis. Alternatively you can pan the graph until the time cursor goes off the edge, whereupon the time cursor is cleared.
- You can add drinks and food by touching the appropriate button. If the time cursor is set, the drink is added at that time. Otherwise it is added at the current time. The time of each food and drink item is the time when the item is started, not finished. The simulation assumes liquor is taken as a shot (very quickly) and all other food and drinks are consumed over 15 minutes.
- Drinks are categorized into single-serving beverages (beers, etc) indicated by a bottle, wines, mixed drinks (cocktails) and straight liquor.
- You can select and deselect a drink or food item by touching it. The selected drink or food item is indicated by a red border and a description of the item is displayed below the graph.
- You can remove a drink or food item by selecting it and pressing the delete button (trash can icon in upper toolbar).
- You can copy a drink or food item by selecting it and pressing the duplicate button (in upper toolbar). The duplicate item is added at the current time or at the time cursor time, if the time cursor is set.
- You can move a drink in time by dragging it. Once you start dragging you can move your finger vertically off the icon so it is not obscured by your finger.
- You can pan and zoom the graph. The graph only shows 16 hours before and 12 hours after the current time. You cannot view data outside of this time range.
- You can tap the graph twice quickly to pan the graph back to the current time or to the selected food or drink item if it is not currently visible.
BAC Levels
- 0.03 - Alertness, judgement, coordination, and concentration are affected.
- 0.05 - Common legal limit for driving in Europe.
- 0.06 - Reflexes, reasoning, and depth perception are affected.
- 0.08 - Common legal limit for driving in the US.
- 0.10 - Reaction time and gross motor control are affected causing staggering and slurred speech.
- 0.20 - Severe motor impairment, loss of consciousness, and memory blackout can occur.
- 0.30 - Death is possible. Breathing and heart rate can be impaired.
- 0.40 - Lethal dose for 50% of people.
Advanced Parameters
There is an Advanced page available from the Profiles page. These parameters are used in the simulation. By default the values are set based on published population averages as well as your profile information. In some cases you may be able to increase the accuracy of the simulation by tailoring it to your physiology.
The Total Body Water (TBW) method most directly affects the peak height of the BAC curve. Increasing your TBW decreases the peak BAC. The Standard method is a combination of Forrest's (Forrest 1986) and Watson's (Watson 1989) methods with obesity extrapolation using Gundersen and Shen data (Gundersen 1966). This method is BMI based and takes advantage of the fact that body fat does not absorb much alcohol and therefore is not a significant factor in BAC simulation. Widmark's method (Widmark 1932) is standard but is not included because it has been shown to be inaccurate, possibly due to outdated population statistics. Since the Forrest and Watson methods of computing TBW are based on average US demographic data, they may not be accurate for rare body types, or for other populations. Similar to the Body Mass Index (BMI) tables, broad demographic averages may not work well for body types such as bodybuilders, who have a much larger proportion of muscle mass than average. If you know your body fat percentage and you know that BMI-based statistics don't apply to you well, you can use the Body Fat method to increase the accuracy of the simulation.
The Alcohol Clearance Rate is historically known as "beta" and is the rate at which the body metabolizes/clears alcohol. Here it is measured in grams per liter per hour, though typically it is grams per 100ml per hour. Beta is the slope of the decline of the BAC curve (when there is no alcohol still entering your blood) at moderate BAC levels. The average beta values work relatively well on average, but do not work well for everyone. If you have another source of information about your beta, for example from an experiment with an accurate breath alcohol tester, then you can increase the accuracy of the simulation by specifing your measured beta here.
Breath vs Blood Alcohol
Note that breath alcohol concentration is not the same as blood alcohol concentration. Breath alcohol testers are of varying quality and may not be very accurate (Hlastala 1998). There can apparently be wide variation between different breath alcohol testers (MPH Magazine, March 2005).
Accuracy
This model has been developed using published data by Wilkinson (Wilkinson et al. 1977) and with many trials using a top-of-the-line commercially available breath alcohol tester, the Alco-Sensor FST from Intoximeters Inc. To the best of our knowledge, the model in IntoxiGraph is one of the most sophisticated models available for human alcohol consumption and clearance simulation. The model is a multi-compartment simulation with both diffusion and physical transfer vectors. Given accurate inputs (including advanced parameters) this may be more accurate than some breath alcohol testers.
- The information provided to the simulation may not be accurate. Every manufactured drink (or batch of drinks) has alcohol content that differs somewhat from the published value. Every mixed drink has different volumes of each liquor in it because the person making the drink usually doesn't measure accurately.
- This software allows the user to override the default Total Body Water computation method and alcohol clearance rate. If the user enters incorrect values the simulation will be accordingly inaccurate.
- By default this software uses a BMI-based method of computing Total Body Water. This method is an estimate that works on average but may be significantly inaccurate for some individuals.
- Every individual is different and therefore a general model cannot be perfectly accurate for any particular individual. People absorb and clear ethanol at different rates, yet by default this model uses standard rates.
- The database in this program may be incorrect about the amount of alcohol in any particular drink or liquor.
- This program may not implement the intended model correctly due to software coding errors.
Credits
The following images are used in this software:
- The Gears image (Settings tab) is public domain from Wikimedia Commons and was created by Xander.
- The Red Wine Glass image was created by Andre Karwath and is used under the Creative Commons ShareAlike 2.5 license.
References
Forrest, A. R. W.; "Commentary: Estimation of Widmark's factor," Journal of the Forensic Sciences Society (1986), 26 (4): 249-252.
Hlastala MP. (1998) The alcohol breath test - a review. Journal of Applied Physiology, 84(2): 401-408.
Gundersen K, Shen G. (1966) Total Body Water in Obesity. The American Journal of Clinical Nutrition Vol 19, No 2, 77-83.
Jackson AS, Stanforth PR, Gagnon J, et al (2002), The effect of sex, age and race on estimating percentage body fat from body mass index: the Heritage Family Study. Int J Obes Relat Metab Disord, Jun 2002;26(6):789-96.
Oneta CM, Simanowski UA, Martinez M, Allali-Hassani A, Pares A, Homann N, Conradt C, Waldherr R, Fiehn W, Coutelle C, Seitz HK (1998) First pass metabolism of ethanol is strikingly influenced by the speed of gastric emptying. Gut, 1998; 43:612-619.
Smith GD, Shaw LJ, Maini PK, Ward RJ, Peters TJ, Murray JD, (1993) Mathematical modelling of ethanol metabolism in normal subjects and chronic alcohol misusers. Alcohol & Alcoholism Vol 28, No 1, 25-32.
Umulis David M., Gurmen Nihat M., Singh Prashant, Fogler H. Scott. (2005) "A physiologically based model for ethanol and acetaldehyde metabolism in human beings". Alcohol. 2006 Jan, 35:3-12.
Watson, P. E., Watson, I. D. and Batt, R. D. (1980) Total body water volumes for adult males and females estimated from simple anthropomorphic measurements. Am. J. Clin. Nutr. 33: 27-39.
Watson PE, Watson ID and Batt RD. (1989) Prediction of blood alcohol concentrations in human subjects: updating the Widmark equation. Journal of Studies on Alcohol, 42, 547-56.
Widmark, E. M. P. (1932) Die theoretischen Grundlagen und die praktische Verwendbarkeit der gerichtlich-medizinischen Alkoholbestimmung. Berlin; Urban & Schwarzenberg.
Wilkinson PK, Sedman AJ, Sakmar E, Kay DR, Wagner JG. (1977) Pharmacokinetics of Ethanol After Oral Administration in the Fasting State. Journal of Pharmacokinetics and Biopharmaceutics Vol 5, No 3, 207-224.