The Poison Oak Defense

by Deborah Blum

Let’s start this story on the last day of May, on a sunny afternoon when 32-year-old James Robinson was arrested in Ogden, Utah for exposing himself in front of an elementary school classroom.

The police report, claimed that he was standing in front of a window, “with genitalia fulling exposed, performing a sexual act.” As he was apparently standing there unaccompanied, I think we can take a guess at what the, um, act involved.

But according to Mr. Robinson, we would be wrong in that speculation. Instead, he insisted, he was merely suffering from a nasty poison oak rash on his private parts. He thought, perhaps, that he’d brushed into some bushes and then perhaps failed to wash his hands before engaging in the, um, act suggested earlier. In private, of course. In front of the school, his defense was that he was stricken by an uncontrollable poison-oak itching frenzy.

I have to admit that this is my favorite such story of the summer. My second favorite was far better publicized but less, I’d have to say, entertaining: High School Musical actor Zac Efron’s encounter with poison oak while cliff-diving in May. This apparently affected the, um, same region of his body as that claimed by Mr. Robinson. 

In other words, “Zac Efron Reveals Poison Oak on Penis”, according to a headline on The Count. In the story, Efron compares his appearance to a zombie from the movie Dawn of the Dead. The journalist telling the story uses a more everyday description, comparing Efron’s skin to a crust made of swollen cornflakes.

I have to say – ick. And also ick – although in a different way – to Mr. Robinson. But if you’re wondering why I’m following this summer’s bizarre poison oak theatricals it’s mostly because I’ve been rather fascinated by the bigger itchy plant story of the season. It turns out that poison oak – and its evil ilk – poison ivy (photo right) are causing a record number of problems this summer for some very interesting reasons. In the last few weeks alone, I’ve tracked story after story after story to that effect.

Why? Well, the simple answer is that the recent cold winter and wet spring, at least on the east coast, made for an ideal growing season for these tough and invasive members of the Toxicodendron genus. For most of us that would mean T. diversilobum (Poison Oak), T. radicans (Poison Ivy) and T. Vernix (Poison Sumac).

Let’s agree that putting “toxic” at the start of a plant’s name, even in Latin, is pretty much a giveaway that this will be troubling vegetation. But the other more complicated explanation for this summer’s uptick in Toxicodedron rash stories is that new evidence suggests that our changing climate is making these plants more poisonous, stimulating their growth in a way that concentrates their uniquely painful chemistry.

The problem substance in poison oak and ivy is an oily resinous substance called urushiol, which oozes between the plants’ cells. Urushiol (the name comes from a tree in Japan whose resin has long been used in lacquers) has a consistency which causes it to stubbornly cling to skin, clothes, picnic blankets, backpacks, just about anything. People can be exposed to it by merely brushing through a patch of poison ivy or oak but the greater the damage to the plant, obviously, the more urushiol is released.

About 85 percent of people tested have an allergic reaction to urushiol and this set obviously includes Mr. Efron. What’s the reason? This yellowish ooze is packed with catechols – benzene rings that trail woven tails embedded with oxygen and hydrogen atoms – which are neatly designed to induce an immune response. Essentially, they stick to cell proteins in a way that makes them so mishapen, that the body mistakes them for alien substances. The result is such a potent auto-immune response that in most people it creates a havoc of swelling, blisters, and painfully reddened skin. 

It hardly seems possible, but research suggests that scenario is likely to get worse. In recent years, scientists have found that the Toxicodenrons happily adapt to rising levels of carbon dioxide in the atmosphere – a major industrial gases associated with global climate change. And among the adapations appear to be an even more virulent form of urushiol forming in the plant structures. At the same time, these particular species thrive in a carbon dioxide rich atmosphere; scientists say their growth rate has increased by some 50 percent or more.

Is this summer’s boom in plant-induced rashes directly related to the increasingly vigorous Toxicodendrons? Certainly, even researchers are speculating about that. Can we blame Zac Efron’s discomfort on global climate change? Let’s call that a stretch (yes, I know, a spectacular stretch). Could our Utah indecent exposure suspect have based his poison oak defense on the well-publicized Efron case? The actor did, apparently, “air” himself out in front of a journalist, explaining that he had to because of the itching.

Still, another stretch. And if so, it didn’t work for Utah prosecutors, who dismissed the idea as “an unusual way to respond to poison oak. They did offer to reduce the charges from a felony to a misdemeanor if he would plead guilty. But that wasn’t because of the poison oak argument. That was because – as it turned out – school had let out for the day when Robinson positioned himself in front of the window and so no children were there to see.

Which raises another possibility – maybe all of these problems could be avoided if we just paid a little more attention to the world in which we stand.

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