Each year, more than 1 million people descend on New Orleans for Mardi Gras, an organized parade of debauchery and alcohol-induced torpor that may be the closest thing modern civilization has to the excesses of ancient Rome. Saturating the scene on Bourbon Street are plastic beads, handed or tossed to partygoers as a kind of currency. Some bare their breasts or offer booze in exchange for the tokens; others catch them in the air and wear the layers around their necks. Roughly 25 million pounds of beads are in circulation annually, making them as much a part of the Fat Tuesday celebration as sugary cocktails and King Cake.

Traditions and rituals can be hard to pin down, but Mardi Gras historians believe the idea of distributing trinkets began in the 1870s or 1880s, several hundred years after French settlers introduced the celebration to Louisiana in the 1600s. Party organizers—known locally as krewes—handed out baubles and other shiny objects to revelers to help commemorate the occasion. Some of them threw chocolate-covered almonds. They were joined by more mischievous attendees, who threw dirt or flour on people in an effort to stir up a little bit of trouble.

Why beads? Tiny tokens that represent wealth, health, and other prosperity have been a part of human history for centuries. In Egypt, tokens were handed out in the hopes they would guarantee a happy afterlife; the abacus, or bead-based system of accounting, used trinkets to perform calculations; pagan pre-winter rituals had people throwing grains into fields hoping to appease gods that would nourish their crops.

Humans, argues archaeologist Laurie Wilkie, display "bead lust," or a penchant for shiny objects. It's one possible reason why Mardi Gras attracts so many people with their arms in the air, elated to receive a gift of cheap plastic.

Mario Tama, Getty Images

The early beads were made of glass before more efficient production methods overseas led to an influx of plastic beads in the 1960s. Unlike some of the more organic predecessors, these beads have come under criticism for being a source of health problems and pollution. Made from petroleum, they often harbor lead that seeps into the soil and rubs off on hands. (One estimate puts the lead deposit after a Mardi Gras celebration at 4000 pounds.) In 2017, New Orleans paid $7 million in clean-up costs to remove discarded beads from drain basins. In 2018, they installed gutter guards to prevent the necklaces from getting into the system in the first place. Meanwhile, scientists have been working to create an even more eco-friendly version of the beads—like a biodegradable version made from microalgae.

Environmental hazards aside, the beads of Mardi Gras have become as much a holiday staple as Christmas stockings or Thanksgiving turkeys. But the passion and desperate need for them is only temporary; in 2018, 46 tons of the beads were removed from just five blocks of the main parade route on Charles Street. And no bacchanal should leave that much bad juju behind.

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