Smokin’ hot: the effect of climate change on tobacco

Last week in the blog, I wrote about the effect of climate change on coca plants. In it, I related a story of a high elevation trip to Peru which had my friend passing out in a hotel lobby and me barely able to walk up the front steps due to altitude sickness – both of us requiring the medicinal powers of coca tea.

What I didn’t tell you about this story, was that when my friend was set up with an oxygen tank to help relieve her altitude sickness, I plunked down right next to her and lit up a cigarette. Now I know you are probably thinking, smoking right next to an oxygen tank is up there with other wise decisions 20-somethings make like starting literary magazines and wearing tiny hats. I’d like to pretend it was my own altitude ailments that were clouding my judgment, but unfortunately it was something far more nefarious – nicotine addiction. Like every good smoker, I adored nicotine, and not even a thin-aired, potentially explosive environment was going to keep me from lighting up.

Now living in California, smoking cigarettes is about as popular as eating conventionally grown vegetables (you horrible monster!!!), so the smoking has ended. But it doesn’t change me from wanting to know how climate change will effect tobacco, specifically nicotine. Fortunately tobacco as a model agricultural organism (and until recently, major cash crop) has ample research associated with it.

As I mentioned last week, increased atmospheric carbon dioxide is going to increase the growth of tobacco plants (smokers say “yeah!”) while decreasing nicotine concentration (smokers say “boo!”). Meanwhile increasing temperature will have no effect on nicotine levels (1). Ok, so all the smokers are now wondering “WTF?”, because in the future there will be both higher carbon dioxide and temperatures – so, will they just cancel each other out? Sorry smokers, but the combination of the two will still decrease nicotine concentrations. This would make your cigarettes less potent if you were just smoking straight tobacco, but fortunately(?) it has been suggested that tobacco companies closely monitor and adjust nicotine levels in cigarettes, so you may not notice the difference (Phillip Morris, please don’t sue me for mentioning this!).

Though people have taken on nicotine as a beloved alkaloid, it isn’t really meant for us. Nicotine is a defensive compound plants use against insects. When insects munch on a tobacco plant stocked with nicotine, they either flat out die or grow slower and smaller (2). Let’s just say that even insects that are well-equipped to handle nicotine, are not well-treated by the stuff (3)—much like humans. So if a plant is larger, juicier and has less nicotine, it is going to be more pleasant for the insects to munch on, requiring greater amounts of pesticides to combat the herbivory.

But nicotine isn’t all about defense, it’s also used to promote reproduction. Wild tobacco plants actually use nicotine (and it’s gnarly, bitter taste) to get hummingbird pollinators to hop from flower to flower (“ew, this one tastes gross”; “oh, this one tastes slightly better!”) (4). The researchers on this study seemed to think that the hummingbirds weren’t addicted to the nicotine, so they must have been slow learners because who keeps going back to food that tastes terrible. In any case, there does not seem to be any studies on how climate change will influence nicotine in tobacco flowers, but if it follows a similar pattern as the leaves, then there will also be a reduction in nicotine. This could reduce cross-pollination as there wouldn’t be as many gnarly tasting flowers keeping the hummingbirds moving.

So suddenly the effect of climate change on tobacco has less and less to do with smokers and industry (and how I gave myself asthma), and everything to do with the birds and the bees (or at least the tobacco hornworms)! With all things climate related, it isn’t just about us people, it turns out that when it comes to having a love affair with tobacco, other animals may be just as dumb.

Minda Berbeco has a PhD in Biology from Tufts University and is a science blogger in the Bay area. Though she had a brief love affair with nicotine, she is now happily married to sunshine, lollypops and other healthy California addictions (plastic surgery??). She would like to note that the relationship between tobacco and climate change goes beyond nicotine levels. An excellent Union of Concerned Scientists report found that the same “scientists” and “researchers” who promoted the safety of cigarettes in the 1990’s are now disputing climate change. Check it out, it will disturb you.

For your reading enjoyment:
(1) Alterations in the production and concentration of selected alkaloids as a function of rising atmospheric carbon dioxide and air temperature: implications for ethno-pharmacology
(2) Effects of dietary nicotine on the development of an insect herbivore, its parasitoid and secondary hyperparasitoid over four trophic levels
(3) Nicotine Keeps Leaf-Loving Herbivores at Bay
(4) Unpredictability of nectar nicotine promotes outcrossing by hummingbirds in Nicotiana attenuata