The Pacific Ocean Is Polluted With Coffee

An anonymous reader writes in with this excerpt from Inhabitat:"People aren't the only ones getting a jolt from caffeine these days; in a new study published in Marine Pollution Bulletin, scientists found elevated concentrations of caffeine in the Pacific Ocean in areas off the coast of Oregon. With all those coffee drinkers in the Pacific Northwest, it should be no surprise that human waste containing caffeine would ultimately make its way through municipal water systems and out to sea – but how will the presence of caffeine in our oceans affect human health and natural ecosystems?"

Amounts

[phantomfive]

Neither the summary nor the linked article said the amounts, but they are listed in the original paper [sciencedirect.com]. In the ocean, they found 44.7 ng/L. "Caffeine concentrations in rivers and estuaries draining to the coast measured up to 152.2 ng/L." For those who like their numbers in ppm, I believe that's .0447 ppm and .1522 ppm, respectively. Sometimes I fail at math, though.

BS

[jbolden]

Not buying it.

An 8 oz cup of coffee is 236.5 ml and has 49mg of caffeine. Assume the entire thing was thrown away undrunk at all. The population of portland is about 600k. If we assume that everyone in portland throws away one full cup of coffee every day for 100 years and that every drop ends up in the ocean, that's 21.9b cups of coffee or approx 1 billion grams of caffeine.

100 years is plenty of time to diffuse. Its also plenty of times for caffeine to break down but less assume this were magic caffeine and so lasted the 100 years perfectly intact. Since they say the pacific ocean lets say none of it leaves the pacific for the other oceans. The pacific ocean is 7.721473366 × 10^21 liters. So cross multiplying (7.721473366 × 10^21× ) x (.049 g) / (.2365 l) us that that we are 1.6x10^20 grams so your billion grams falls 1.6x10^11 short. OK well lets assume that in addition to not breaking down it also doesn't diffuse. The Pacific is 361.1m kilometers in area. So lets assume that all the coffee hangs out for the entire century in the 2 kilometers nearest Portland, we still are short by 3 full orders of magnitude.

There is no way a bunch of 600k humans use enough coffee for the ocean to notice.

Re:Amounts

[NixieBunny]

I believe that you're off by a factor of a thousand. A liter is a kilogram of water, so a nanogram per liter is one part per trillion, or million million as the Brits like to say.

One hundred parts per trillion is rather difficult to measure, but these folks have found a way to do it.

The question is: will a concentration that low have any effect on sea life?

Re:How come the water don't smell like coffee?

[LordSnooty]

They say tea contains caffeine and yet I can drink one before bed and not feel any effects of insomnia. The reverse is true if i drink coffee. Are there different types of caffeine or is there a lower concentration in tea?

Re:How come the water don't smell like coffee?

[cmdr_tofu]

Green tea has less caffeine than black tea, but arguably is much healthier (http://nutritionfacts.org/video/coffee-vs-tea/). Green tea is less processed than black tea, but white tea which is even less processed has less caffeine and may have the most health promoting properties. I've swapped out my daily pot of joe with a daily pot of green/white mix and do feel a lot better! Even with a few chocolate espresso beans now and then, no insomnia :)

Re:How come the water don't smell like coffee?

[holysin]

While tea does contain tanin so does coffee. A more common reason as to why you can do this is either you're drinking a fruit /mint tea that has little to no caffeine, or more likely, your body is conditioned for coffee so that when you smell coffee and taste it your brain behaves as though it's just waking up even if there's not a lot of caffine in the cup. An example of this was a study (in england around 2011 if my memory serves) that had people drink regular coffee and decaf and then tested focus and reaction time. The people drinking decaf who were told they were drinking caffeine actually did better than the caffeinated people on (I think just on) reaction time. The brain is an annoyingly inconvenient trickster sometimes.

Re:How come the water don't smell like coffee?

[tomhath]

For many people withdrawal from caffeine means a migraine headache. I've told several coworkers who complained of severe headaches on Mondays that they need to drink the same amount on weekends as they do in the office.