Poison Ivy, Sunscreen, and Ingestible Thermometers

Poison ivy produces an oily sap called urushiol throughout the plant. Exposure to that oil causes an allergic reaction in about 85% of people. Urushiol is extremely durable and can remain on clothing, fur, or tools for long periods after initial exposure. If you're exposed to it, wash thoroughly with cool water and a degreasing soap, then use rubbing alcohol and scrub under the fingernails with a brush, and wash all the exposed clothing. Poison ivy can also be extremely toxic if inhaled, so the plant should never be burned.

> See if you know how to recognize poison ivy. (More, w/quiz) 
> Urushiol can remain allergenic on clothing for up to five years—or longer. (More)

When urushiol comes into contact with our skin, it binds to skin proteins, ultimately triggering an immune system response as if the body's under attack. The resulting inflammatory response leads to the rash and other uncomfortable symptoms.

> Poison ivy is in the same family as mangoes, cashews, and pistachios—see why we (usually) don't get sick from encountering or eating them. (More)

> Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity. (More)

> Experiments in the 1990s simulated potential 2050 conditions—learn how poison ivy fared. (More)

The plant typically has three leaves but can otherwise look highly variable. It can grow as a ground shrub or a vine, and it can vary in color and even in its leaf shapes—though generally the leaves are broad. Urushiol can cause itching and a red rash within a few days of contact. Fluids from resulting blisters are not contagious. Poison ivy's effects may be seen at different times depending on the area of the body and the thickness of the skin there.

> Sensitivity to urushiol seems to have a genetic component. (More)

> See how climate change is poised to affect poison ivy. (More)

Discover more: 

> During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians. (More, w/audio)

> After being exposed to poison ivy for the first time, for some people, it can take several weeks to develop a rash. (More)

 News in Context 

1440 brings you the knowledge and context behind intriguing news stories:

FDA approved a new sunscreen ingredient, making it better and lighter. (More)

> A massive exoplanet seems to have snow with a major sunscreen ingredient.

> How do mineral and chemical sunscreens work?

Since 2025, the massive US measles resurgence has included more than 900 confirmed cases in Utah and Arizona alone. (More)

> Measles is extremely contagious—it can remain in the air for two hours.

> Measles evolved from an ancient cattle disease.

A National Geographic cruise had a norovirus outbreak last month, sickening 12 of 89 people aboard. (More)

> There were at least 23 gastrointestinal illness outbreaks on cruises last year.

> The first reported norovirus outbreak sickened half an elementary school—and the illness is named as a nod to the Ohio town where that occurred.

This month, two researchers were charged with smuggling mpox into the US. (More)

> Mpox, formerly known as monkeypox, doesn't come from monkeys. 

> See an image of mpox virus particles, taken at a biosecure facility.

Medical Developments Spotlight

We love spending time learning about the latest medical breakthroughs and spotlighting research that piques our interest, may influence future research directions, or inform healthcare conversations. Here's what we found this week.

Scientists have invented an ingestible body thermometer

MIT News | Anne Trafton. The tiny blueberry-shaped sensor was tested in pigs, though it's designed to one day continuously send temperature updates from the human GI tract to help doctors stay abreast of potential infections in vulnerable populations, such as those who are immunocompromised. It may also help monitor people during anesthesia or assist with fertility tracking. (More)
 

> The normal human body temperature isn't 98.6 F—now it's commonly 97.9 F.

Climate change is tied to growing drug resistance genes in Salmonella

The Guardian | Andrew Gregory. Recent analysis of 480,000 Salmonella genome samples collected over more than eight decades, compared with average temperatures and rainfall over that period, suggests that about 10% of the increase in Salmonella antibiotic resistance genes may be attributable to climate change. Rising temperatures and changing rainfall distributions can influence how the pathogen survives, mutates, and spreads. (More)
 

 > Some researchers suspect US President Zachary Taylor died from eating food contaminated with Salmonella in 1850.

Secondhand smoke linked to worrisome elevated cadmium levels in the body

Texas A&M University School of Public Health | Ann Kellett. Heavy secondhand cigarette smoke exposure is associated with elevated levels of toxic cadmium in adults' blood, with new analysis indicating the exposures led to levels about 1.5 times higher than what's found in adults' bodies in smoke-free environments. Women had particularly higher levels. Children's levels remained unchanged, potentially because the metal accumulates over time, and aging bodies may also be less efficient at clearing the substance. (More)
 

> Smoking is the biggest modifiable risk factor for macular degeneration.

 Etcetera 

> The pandemic boosted supplement sales, and the trend endured.

> Could goose bump research lead to new ways to restore hair growth?

> World records are often broken later in the day—are muscle clocks the difference?

> Good news: Pollen allergies rarely cause anaphylaxis. 

> Q-tips were originally designed to clean babies.

> Mosquitoes are the world's deadliest animals; see what others make the list. 

> Yes, many animals can get malaria, often with symptoms similar to ill humans. 

> Our gut microbiome may affect our heatstroke risk. 
 

> Too little stress can cause health problems, too. 

> Antidepressants alone may fail as many as half of depressed patients.

> Learn why loneliness is more dangerous to your overall health than smoking.