Dermatologists Have Bad News to Share About Climate Change

If you’ve been avoiding making your annual skin screening appointment for, like, years, rest assured that some things never change: Dermatologists are still obsessed with telling you to wear sunscreen, and your mole probably isn't cancerous (you should get it tested, anyway). But while paper robes with confusing openings aren’t going anywhere, conversations about climate change don’t typically make it into the examination room.

Some doctors think maybe they should. Our skin is our largest organ as well as the one that interacts most immediately with our environment, serving as the first line of defense against harmful microbes; a barrier against UV radiation and pollution; and a regulator of our body temperature via sweat glands. It is, as a result, on the frontline of how our bodies handle their increasingly extreme environments.

Though the International Journal of Women’s Dermatology devoted an entire 2020 issue to climate change, which ran over 120 pages, looking at dermatology through a climate lens is still gaining traction in the medical community.

“When I lecture about climate change, I invariably get lower grades and more negative comments, including hate mail,” Dr. Misha Rosenbach, an associate professor of dermatology at the University of Pennsylvania, co-founder of the American Academy of Dermatology’s climate change and environmental issues expert resource group, and the co-author of the Women's Dermatology introduction told me, speaking in the capacity as an individual. “And every time I give a lecture, someone will stand up and say it’s a hoax from China — like literally, without fail, no matter what venue, some doctor says it’s a hoax.”

At the same time, the dermatologic response shouldn’t be limited to “wear more sunscreen” and “limit your time in wildfire smoke.” Since our skin is our primary defense against the external world, it is also being impacted in as many ways as there are expressions of climate change. Here are just a few, broken down loosely by American geography.

In the East

The northeastern United States is warming faster than the rest of the country, and unlike the southern U.S., where climbing temperatures will make regions far less habitable, winters and shoulder seasons in the East are becoming, well, pretty pleasant!

But the good weather also means people are spending more time outside. And remember the ozone layer? Though the Montreal Protocol in 1987 helped eliminate the chemicals that were causing its depletion and consequently exposing people to higher levels of UV radiation, its full recovery isn’t expected “until 2050,” the World Health Organization warns. Skin cancer rates, partially as a result, have been rising: Between 2000 and 2010, the overall rates of basal cell carcinoma rose 145 percent and squamous cell carcinoma rose 263 percent, the American Academy of Dermatology reports.

More time outside also means more exposure to pollutants generally. “I grew up in Harlem,” Dr. Lynn McKinley-Grant, the current president of the Skin of Color Society and an associate professor of dermatology at Howard University College of Medicine, told me. “The people who grew up there have a lot of these diseases that affect the skin like sarcoidosis and lupus” — an inflammatory disease that can cause small growths on the skin, and an autoimmune disease that can cause rashes — and “there are some people who have had mycosis fungoides,” a skin cancer that often begins its presentation with a rash. “It’s something we’ve seen for a while,” McKinley-Grant went on, “unrelated to the sun but related environmentally to things that affect us.”

“Urban air stagnation events” — four or more days of low wind speeds and little precipitation, when pollutants can settle — are also a risk, the International Journal of Women’s Dermatology’s introduction adds. Those pollutants can trigger autoimmune skin diseases like lupus, and a blistering disease called pemphigus vulgaris also has “increased hospitalizations if there’s high pollution in the environment,” Rosenbach told me.

There are small annoyances, too: Apparently more CO₂ also means more poison ivy.

In the North

Pollen seasons across the country are getting worse due to climate change, but particularly so in places like Wisconsin, Minnesota, North Dakota, and parts of Canada — something any sufferer of seasonal hay fever will tell you can quickly develop into a nasty dermatology concern.

Speaking of nasty, research also shows that increased rainfall in the Great Lakes region due to climate change is resulting in a runoff of “metals, pesticides, pathogens, and fecal indicator bacteria” into recreational waters. “Summertime bacteria concentrations in an inland lake in Wisconsin,” for example, exhibited “positive, significant correlations” with the amount and duration of seasonal rainfall. Swimmer’s itch also appears to be on the rise due to warming temperatures. Fun!

Then there’s Lyme disease, which causes a rash that, if addressed quickly with antibiotics, can head off the development of more serious post-treatment Lyme disease syndrome. The concern is, ticks are now moving into areas where they haven’t been seen before — “dermatologists in Canada went their whole careers without ever encountering Lyme disease,” Rosenbach said — as well as emerging earlier in the season and hanging around through the late fall. “And that ... can mean that you’re not expecting Lyme disease [when] it walks in the door,” Rosenbach said. “And if you don’t recognize that, you can have severe consequences.”

Alaska, meanwhile, gets to enjoy thinking about a “worst-case scenario” of smallpox re-emerging from the melting permafrost.

In the West

When a fire burns through the West, it doesn’t just burn trees — there are cars, houses, and other not-great-to-breathe-in materials being incinerated and ending up in the air. Our skin doesn’t love that. Last year, a study that looked at the 2018 Camp Fire near San Francisco found that instances of eczema rose in local health clinics compared to 2015 and 2016. “Fully 89% of the patients that had itch during the time of the Camp Fire did not have a known diagnosis of [eczema], suggesting that folks with normal skin also experienced irritation and/or absorption of toxins within a very short period of time,” one of the authors said.

Skin is also affected by pollution, which disproportionately affects Black and Latino neighborhoods. Due to historic redlining, these areas are often “low-income, densely populated urban areas adjacent to industrial activities and lacking green spaces,” conditions that compound “health impacts such as chronic dermatitis exacerbations and carcinogenic skin damage,” the International Journal of Women’s Dermatology found. One study that looked at pemphigus flares — that’s the blistering autoimmune disease — “found an association between UV index and hospital admissions only in the subset of Hispanic/Latino patients,” despite using a representative U.S. sample.

The high heat in the West is also a concern since being unable to properly cool off via sweat can cause heat-related illnesses, currently the leading cause of death from extreme climate events in the United States. “The laborers who are out there working in the sun, not only do they get skin cancer, but they end up getting very dehydrated,” McKinley-Grant said, citing studies that have found high rates of kidney failure in agricultural workers and construction workers who labor in high heat conditions.

In the South

If you’re taking a dermatology board exam and the question mentions that a patient went camping in Costa Rica, “everyone knows the answer is leishmaniasis,” Rosenbach said. “The key word is ‘Costa Rica.’”

Leishmaniasis is a parasitic disease spread by sand flies that can cause skin sores and impact internal organs, but it’s taught to aspiring doctors as being a tropical and subtropical disease. Yet parts of the United States are now subtropical too, including Texas and Oklahoma — where, indeed, endemic leishmaniasis cases have begun to appear. But if dermatologists aren’t looking for leishmaniasis in patients with no travel history, they could miss a crucial diagnosis.

Speaking of new diseases, “chikungunya and dengue are now reported within the southern United States, with Zika on the horizon,” one of the papers in the Women’s Dermatology special issue found. And with more powerful storms and flooding slamming southern coasts, “there is terrible dermatitis,” said McKinley-Grant, who has seen firsthand how unidentified infections arose in patients in North Carolina after they waded through waters up to their waists. In extreme environmental conditions such as we live in now, infections of any kind “need to be addressed immediately,” McKinley-Grant went on to stress, even if they seem as innocuous as a bug bite.

Skin problems are actually the “most common issues” medics see after major storms, Rosenbach said. Part of the reason is simple things, “like laceration from flying debris,” he went on. Part of it is that when water rises, “humans and animals are in closer contact, you get animal bites and things like that.” And part of it is that when “you get standing water [...] it releases some of these vector-borne things.”

Oh yeah, and then there are jellyfish. Seabather eruption, an itchy skin reaction caused by jellyfish larvae, “has become increasingly common potentially because of increased ocean temperatures,” the Women’s Dermatology paper found. “This eruption can occur in up to 16% of patients swimming during peak seasons in southeast Florida.”

So where do we go from here?

If you go to the hospital for a broken hip, a doctor might suggest a home safety search. Someone will come to your house, tape down your carpets, and move low-hanging objects in order to prevent future trips and falls.

Rosenbach envisions a future where doctors would do the same for something like repeated childhood asthma hospitalizations. “What if someone at your house was like, ‘Hey, you have a gas-burning stove, and you have mold here, and you’re actually losing a lot of heat through these single pane windows and no insulation. And what we should do is, get rid of your gas stove, rip out this mold, and make your environment better and have some air filters, or whatever,” he mused. “Imagine you could go and make these changes, and suddenly this kid never had asthma anymore, never [needed to be] admitted to the hospital.”

Rather than play whack-a-mole with medical symptoms, then, Rosenbach is thinking like a dermatologist — that is, we ought to cut out the real cancer, which is our dependence on fossil fuels.

Admittedly, that’s daunting to tackle if you’re more immediately concerned with the weird rash you keep getting at the beach. But beyond “eating less meat, flying less, electrifying everything,” from a health-care standpoint, “I don’t think a lot of people think about talking about climate change with their medical team,” Rosenbach said. “And if they do, it pushes the medical team to educate themselves and educate the field.”

Good news for oversharers — talking about your weird rash with friends and acquaintances is also praxis. “No one should be afraid to say, ‘I saw my doctor and they said I got Lyme. I got bit by the tick in February, because of climate change! That’s kind of crazy!’” Rosenbach added. “Just having those conversations and showing people that these are real-time impacts that they’re experiencing I think is important.”