Good morning, Quartz readers!
You may have never heard of PM2.5. But if you plan to continue breathing, it should at the top of your vocab list.
PM2.5 is the technical term for fine particulate matter measuring 2.5 micrometers or less in diameter. It’s the smallest unit of air pollution, the kind spewed out of wildfires, car exhaust, and power plants that burn fossil fuels. It’s small enough to invade human airways and slip into the bloodstream.
Exposure to PM2.5 air pollution has detrimental effects on the heart and lungs. It hits babies and the elderly hardest, and exposure in the womb has long been associated with an array of adverse outcomes that include preterm birth and low birth weight.
There’s also mounting evidence that PM2.5 can penetrate our brains. In the US, scientists found that counties with higher levels of PM2.5 had higher rates of dementia—and that when PM2.5 levels fell, dementia prevalence decreased.
There are still many unanswered questions, including how long it takes for the particulate matter to damage our cells, or if it’s possible to recover by breathing cleaner air later on. But scientists estimate that, globally, PM2.5 exposure caused 4.2 million deaths in 2015. They can also calculate the health impact increases in particulate matter will have on a population. For example, we know that the Trump administration’s proposed rollback of Obama-era coal regulations could lead to up to 1,400 more premature deaths a year in the US.
A recent World Health Organization (WHO) report postulated that bringing global PM2.5 exposure down to levels it says are protective of human health would eliminate the same number of deaths as globally eradicating breast and lung cancer in terms of life spans.
However, right now 95% of the global population is exposed to PM2.5 levels exceeding the WHO’s recommended levels—and that pollution has steadily increased in the past decade.
As the science on what these tiny particles can do to us matures, checking local air quality conditions—and transitioning to cleaner fuel sources—will hold more and more meaning for our health.—Zoë Schlanger and Katherine Ellen Foley
Five things on Quartz we especially liked
The rise of “stochastic terrorism.” The term refers to “the use of mass communication to incite random actors to carry out violent or terrorist acts that are statistically predictable but individually unpredictable.” As Heather Timmons writes—following bombs being mailed to prominent Democrats this week—the increasingly hostile nature of political discourse in the US (and beyond) makes such attacks more likely.
The story of a Nigerian migrant. It’s one thing to know that many young Africans try to reach Europe for a better life and get exploited by smugglers along the way. It’s another to become immersed in the painful story of one such migrant. Yomi Kazeem details the tortuous path taken by one young man from Nigeria to Italy through Libya and across the Mediterranean.
A US city’s blueprint for fighting the opioid epidemic. The community of Winchester, Virginia has united to form a uniquely compassionate approach, establishing a drug court, a “Church of Addicts” for people in recovery, and a hospital program that invites volunteers to cuddle babies born dependent on opioids. The city, as Annabelle Timsit writes, “seems to have created a system that pushes treatment over incarceration, and support over judgment.”
The global banana wars have begun. Super-cheap grocery stores have taken hold in Europe and are now spreading to North America. But how do they keep costs so low? As Chase Purdy reports, one method is hostile negotiation. The German brand Aldi has demanded that its Colombian suppliers of bananas drop their prices ASAP—or Aldi will drop them. The tactic could lead to lower-quality bananas throughout Europe.
What makes music scary? Played in sequence or together, the notes F and B clash in a way that feels twitchy, unnatural, and foreboding. As Gwynn Guilford explains in time for Halloween, the demonic combo was taboo in medieval Europe and referred to as diablous in musica—literally, ”Satan in music.” But it was later embraced by the likes of Berlioz and Beethoven—and, much later, by Black Sabbath and Metallica.
Five things elsewhere that made us smarter
India’s electric-rickshaw revolution. Drivers of the ubiquitous three-wheelers have discovered that e-rickshaws are cheaper to maintain than the traditional variety, not to mention faster, quieter, and cleaner. As Jill Ward and Anindya Upadhyay write for Bloomberg, India’s fleet of e-rickshaws has grown to about 1.5 million—bigger than the total number of electric passenger cars sold in China since 2011—despite little help from the government.
A quarter of the women in America identify as Republican. To outside (particularly liberal) observers, they might be a mystery: Why support a party that increasingly seems to work toward their detriment? Yet research by Christine A. Kray, Hinda Mandell, and Tamar Carroll finds such women equate protecting the interests of their family (and of the men in them) with furthering their own.
The story behind a body found in Manhattan. In a city under the constant gaze of security cameras, where residents have long been urged to report anything suspicious, a corpse sat behind the wheel of a car for a week—on a busy street during a heat wave. For the New York Times, Michael Wilson tells the tumultuous life story (paywall) of the man who parked and never left.
China’s AI ambitions. Artificial intelligence in China is already a powerful enabler of authoritarian rule, with the government facing few legal constraints while accessing the enormous amounts of personal data generated by consumer tech services. But as Nicholas Thompson and Ian Bremmer write for Wired, China aims to become much more: an AI superpower exporting its techno-authoritarian revolution to the world.
The humanification of pet food is nearly complete. Pet food—particularly the high-end variety—is edging ever closer to human food, and the overlaps between the two categories can be uncanny, writes Joe Pinsker for the Atlantic. Look no further than non-GMO, American-made goat’s-milk pumpkin-spice lattes for dogs—a real product sold by a real company.
Our best wishes for a relaxing but thought-filled weekend. Please send any news, comments, air filters, and fancy dog food to hi@qz.com. You can follow us on Twitter here for updates throughout the day, or download our apps for iPhone and Android. Today’s Weekend Brief was edited by Steve Mollman.