You Are What You Pee: Estimating Alcohol Consumption from Community Wastewater Samples

One downside to collecting self-reported data on alcohol consumption is that people might underestimate their drinking habits for a variety of reasons.  Additionally, these types of data collection methods, coupled with other methods such as collecting census data or other sources, can be time consuming and expensive, so alternative methods for collecting alcohol consumption data might be beneficial for tracking various alcohol-related public health concerns in a given community.

Community wastewater is one method for tracking various indicators of public health in many parts of the globe, from alcohol and tobacco to recreational and illegal drugs and everything in between.  While there have been studies in Europe using wastewater to estimate community alcohol consumption, to date there haven’t been any studies in the United States on the specific subject (with the exception of the short study presented today).  Those studies

Photo courtesy Flickr user Montgomery County Planning Commission

tracking alcohol consumption through wastewater in Europe have been found to be well-correlated with alcohol consumption data collected through more traditional methods, indicating that it might be a viable approach for collecting alcohol consumption data in other parts of the globe as well.

Currently, to estimate community alcohol consumption from wastewater, ethyl sulfate (EtS) is the primary compound that has been measured. It is a minor phase-II metabolite of alcohol, and has been shown to be relatively stable in the wastewater environment. Ethyl glucuronide (EtG) has also been measured in the past, however, this compound isn’t as reliable due to its relative instability in wastewater.

The goals of the study presented today were to; 1) be the first study to use wastewater to estimate alcohol consumption in U.S. communities; 2) estimate alcohol (and tobacco, which I’m not covering today) consumption over a years’ time; and 3) compare these results to WHO, CDC, STATE, and NIAAA data from the same period.  This study is currently available online and is in the March 2019 issue of the journal Science of The Total Environment.

Note: this is going to be just a quick summary, so if you want more details, just ask and I’ll see if I can dig up the answers.

BRIEF METHODS

24-hour composites of raw wastewater were collected one weekday per month for 11 months at three different communities in the United States.  Two communities (A & B) were located in the Midwest, while the third community (C) was located in the Northeast. The total population represented in these three locals was approximately 222,000 people.

Ethyl sulfate (EtS) was chosen as the marker for alcohol consumption for this study, and was evaluated in wastewater samples using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS).

Mathmateical analysis calculated the estimate alcohol consumption habits of each community based on the EtS in wastewater data, and compared with data collected by the WHO, CDC, STATE, and NIAAA.

SELECTED RESULTS

  • Mean estimated weekly alcohol consumption for each community was:
    • Community A: 24.7mL/day/capita (range: 15.5-43.3mL/day/capita)
    • Community B: 17.9mL/day/capita (range: 5.7-46.4mL/day/capita)
    • Community C: 49.8mL/day/capita (range: 21.5-92.9mL/day/capita)
  • Photo courtesy Flickr user Damien D.

    Weighted population average weekly alcohol consumption for the three communities was 29.4mL/day/capita.

  • Annual alcohol consumption for all three communities was calculated to be:
    • Community A: 13.3L/year
    • Community B: 9.6L/year
    • Community C: 26.8L/year
  • Weighted population average yearly alcohol consumption for the three communities was 15.8L/year.
  • There were no significant differences in alcohol consumption levels between Community A and Community B, however, Community C exhibited significantly higher levels of alcohol consumption than the other two communities.
  • WHO data pegged alcohol consumption levels for the three communities at:
    • Community A: 30.9mL/day/capita
    • Community B: 22.3mL/day/capita
    • Community C: 62.2mL/day/capita

CONCLUSIONS

Overall, this study is assumed to be the first study estimating alcohol consumption habits in US communities using wastewater. Focusing on EtS and comparing with data collected from other organizations from more traditional methods, the researchers found many similarities between the two data sets.  Comparing the wastewater data with WHO data for the three communities, the values were relatively similar.

On the community level, it was noted that Community C was significantly higher in regards to their alcohol consumption, which the researchers attributed to the fact that this community was a known tourist area, so alcohol data could very well be skewed by the tourists and is not actually representative of the alcohol consumption habits of the local community alone (it could be an overestimation).

Lots of limitations to this study (I won’t go into all of them but will briefly touch on a couple).  One of the biggest ones is probably when the samples were taken. Only weekday samples of wastewater were taken, thus leaving out potential data from the weekend that might influence EtS levels (and thus overall alcohol consumption levels).  Of course, taking samples one day per week could still potentially capture some weekend data if 1) EtS was stable enough and 2) the wastewater sample included some wastewater from the previous days including weekend days.

The only compound used to estimate alcohol consumption in this study was EtS.  While it is known to be relatively stable, it is still possible to have some degradation in the wastewater system. To the researchers’ credit, however, there really isn’t a standard method for determining alcohol consumption in wastewater, so it’s all still highly experimental in nature.

The choice of which community to examine may have also influenced results slightly.  Specifically, Community C is a known tourist area, while the other two communities were not, so it makes it difficult to compare between them.  Additionally, traditional data collection

Photo courtesy Flickr user Johnn

methods like censusing and surveying may render the comparison to wastewater data difficult, since the more traditional methods do not generally include information from tourists.

Overall, the estimations of alcohol consumption based on EtS levels in wastewater appear to be consistent with other studies conducted in Europe and elsewhere. These levels also seem to correlate relatively well with traditional census/survey data, indicating that using wastewater data to estimate alcohol consumption at the community level could be a viable methodology worthy of further study.

SOURCE:

Chen, J., Venkatesan, A.K., and Halden, R.U. 2019. Alcohol and nicotine consumption trends in three U.S. communities determined by wastewater-based epidemiology. Science of The Total Environment 656: 174-183.