Today lets dive into a PLoS One publication from April 2018 titled "Anthropogenic contamination of tap water, beer, and sea salt. It's not brand new, but I noticed that it has been getting some traction on other social media platforms so it might be advantageous to give the article itself a break down.
This Article Concerns Anthropogenic (Human Caused) Plastic Contamination
We have known for over 40 years that consuming plastic isn't healthy for our planet. Over those decades a whole host of studies have been performed looking at all of the places that plastic ends up. The studies found that from our lakes [2] to our oceans [3] to our air {4] our environment is ubiquitously filled with plastics. Some of the more pervasive of plastics are the smallest, known as 'micropastics.' Microplastics are plastic pieces that are less than or equal two 5 microns (that is 0.00004 inches for the imperialistic Americans or 0.0005 cm for everyone else) in diameter and their study poses a challenge for researchers due both to the fact that there are so many different compounds from which they can be made. [5, 6]
Part of the reason why plastics are such a problem is due to the fact that they are able to absorb a variety of other hydrophobic compounds (I am sure you have heard about the problems of BPA in water bottles!) and that these compounds, and as a result, plastics can cause cancer among other diseases. [7, 8] Knowing this, and taking into consideration the pervasiveness of plastics in the environment it should come as no surprise to you that plastic contamination has been found in human consumer goods. But how far reaching is this contamination?
This is just the question the authors of today's subject study wanted to find out. And to begin they focused here on three consumer goods: beer, sea salt and tap water. As these are three things which prior studies had identified plastic contamination in the past, however those studies focused only on a particular product or water from a specific region and don't address how wide spread the issues really are.
Water Contamination
To get a widespread view the authors used 159 water samples sourced from 14 different countries: Cuba (n = 1), Ecuador (n = 24), England (n = 3), France (n = 1), Germany (n = 2), India (n = 17), Indonesia (n = 21), Ireland (n = 1), Italy (n = 1), Lebanon (n = 16), Slovakia (n = 8), Switzerland (n = 2), Uganda (n = 26), and the US (n = 36); and explored the number of plastic particles which were present per liter of the water sample. They did this by filtering water through a 0.25 micrometer pore containing filter that would catch any of these small plastic particles and then using a Rose Bengal stain to be able to see the plastic against the stained fibers of the filter.
Plotted Data From [1] Table 4
The results from the tap water samples they report I have plotted above for you in excel. The authors state that they found plastic particles in 81% of the samples they tested. With the highest concentration of plastics found in water from the US (damn it) and the lowest in countries from the EU (good job Europe). The majority (over 98%) of the plastics they observed were fibers (like what we see below on the right hand side). However there were also a few chunkarinos in there too (like the blue blob below on the left).
Municipal Water Plastic Contaminant Colors; reproduced from [1] Figure 2
The authors also tabulated what colors the plastics were in the samples, which is also morbidly interesting. As you can see from the image to the right, the majority of the plastic contamination was Blue, Pink or Brown. I am sort of surprised there wasn't more clear plastics.. just due to the sheer volume of clear plastic bottles I see in stores! However that ranks forth most prevalent. Makes one wonder where all the blue plastic pieces are coming from!
Beer and Salt Contamination
Similar to water the authors tested some beer. They didn't specify the brand of the beers but they did state that they were all US breweries and all sourced the water for their beer production from the US Great Lakes (oh no...). The beers were all in aluminum cans or glass bottles.
The authors found that all but one of the beers were full of plastics.
Even more interestingly, they ran water samples from the same location as the breweries and compared the amount of plastics from the water vs the respective beer. The authors identified no correlation between the water and the beer, meaning that the plastics which were found in the beer were due to the brewing process and weren't just carried along in the water from which the beer was sourced. In case you are curious I included the color profile of the plastics in the beer, by and large it mirrors the plastics found in the water samples with blue plastic being the most common again (weird!).
Finally the authors looked at sea salt, where the authors tested 12 different brands and you guessed it.. found plastic particles in ALL OF THEM. The salt samples had plastic concentrations of around 7-51 particles per 50 grams. The average serving size of sea salt is around 400 miligrams, thus you would end up with 0.056 - 0.41 particles of plastic per serving depending on the brand of salt you choose. I won't list all of the locations that the salts were sourced, but they appear to be across the globe (Pacific, Hawaiian, Celtic, Himalayan) however I suspect that the processing of the salt samples has more relevance to the plastic content, then the sourcing location (much like the beer).
We got our plastic color on for all the rest of the samples, so lets not stop now (to the right)! Looks like Blue wins again for salt contamination, followed closely by pink.
Brief Conclusions
There is quite a bit of variation in the amounts of plastics found in water samples between countries/locations! However generally most 'developed' nations have microplastics contaminating their municipal water supplies. Beer brewed in the US is also seemingly contaminated with plastic, and at rates which exceed municipal tap water. Even sea salt is contaminated. So it is very likely that most things that we drink or eat have at least a high likelihood of microplastic contamination.
What can be done?
Given how pervasive the plastic is, I don't think there is an answer. You can't escape the plastic as basically everything we could do to purify things involves plastic yet again. You can't exactly avoid drinking water, since it is essential to ...living.
Should I be worried?
No, you shouldn't, but you should at least be informed. We do know that the chemicals which can leach from plastics are not healthy for us, however these plastic concentrations are still very low, so the concentrations of exposure of the chemicals would be infinitesimally small. Clearly this illustrates the importance of environmental plastic removal efforts, hopefully in the future we can work to better reduce our exposure to these tini plastic particles.
Other Cited Materials
Images
Text Sources
- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0194970
- https://www.ncbi.nlm.nih.gov/pubmed/24449922
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5812987/
- http://www.publish.csiro.au/en/en14167
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873019/
- https://oceanservice.noaa.gov/facts/microplastics.html
- https://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=26
- https://www.ncbi.nlm.nih.gov/pubmed/25813067