Why it's so hard to end the use of toxic lead

Pollution from lead battery recycling has led to widespread contamination

Many small-scale operations worldwide remain unregulated, bypassing environmental regulations and causing increasing health threats, primarily to children. A 2020 report by UNICEF found that one-third of the world's children are being poisoned by lead from recycled batteries, among other sources.

Rare earth elements may be extracted from mine waste and coal ash

Rather than focusing solely on new mining operations, which can take decades to establish, some startups are developing methods to extract these metals from the toxic waste of existing operations and thereby minimize environmental impacts. (Some readers may experience a paywall.)

What the research says about the link between lead pollution and crime

The lead-crime hypothesis links childhood lead exposure to impulsivity and aggression as an adult, traits typically associated with higher crime risk. A 2022 meta-analysis found that reducing lead may explain up to 28% of the US homicide decline, but not the broader crime drop.

The widespread need for rechargeable batteries has fueled surging lithium demand

As of 2025, the average person uses 27 times more mined lithium than they did in the 1990s, with the US ranking second globally in consumption despite producing less than 1% of global supply. However, potential alternative materials and boom-and-bust cycles have challenged the profitability of mines and future demand for the mineral.

The history of metallurgy: an interactive timeline

Humans have long been shaping metals into useful tools and aesthetic accessories. By 8,700 BCE, humans already had mastered four types of casting copper. Within a few thousand years, people were combining metals to make the alloy bronze and had...

Supplements often have issues with impurities, toxins, and inaccurate labels

Consumer Reports' tests of more than 20 supplement powders and shakes in 2025 found that more than two-thirds of them contain unsafe levels of lead. Some contained 10 times the amount of lead that's considered acceptable to ingest in a day. The levels they found, in some cases, were even higher than when they tested the products 15 years earlier.

Gold's electrical conductivity, reflectivity, and catalytic capabilities make it scientifically valuable

Although gold has been prized since its use in 40,000 BCE for decorative purposes, it has more recently served as a replacement for mercury in the production of PVC plastic. Because gold does not react with air or corrode, it has remained in circulation and reused in electronics and biomaterials.

The ancient Romans invented the first known artificial sweetener—it involved lead

The product was known as "sugar of lead." It was made by boiling wine in lead pots, concentrating the grapes' natural sugars and adding sweetness from the lead that leached into the grapes. The substance was used until roughly the 1880s for medicinal purposes and also to sweeten wine. (Some users may encounter a paywall.)

The prevalence of microplastics came from plastic’s affordability and versatility

Microplastics' durability and overuse have led to massive pollution that overwhelms the planet's ecosystems. Avian, terrestrial, and marine life have been observed to contain microplastics in their bodies, but reverting to paper, cotton, and other materials in manufacturing also brings environmental challenges.

Stainless steel and cast-iron pans should be used over older nonstick cookware

Although modern nonstick pans avoid forever chemicals like PFOA, they were previously used in the manufacturing of Teflon coatings and have been linked with certain types of cancer, infertility, and other adverse health outcomes. Vintage plastic utensils should also be avoided due to the leeching of contaminants in early formulations of plastic.

The story of the Radium Girls, who exposed the dangers of radioactive paint

After radium was discovered in 1898, companies began using radium-based paints on watch and clock dials to create a glow-in-the-dark effect. Women who worked to apply the paint were encouraged to use their lips and tongues to help create the fine point needed to draw small numbers, unknowingly poisoning themselves.

An overview of helium, the nonrenewable resource that's lighter than air

The second element in the periodic table naturally forms deep underground over the course of billions of years through the decay of radioactive elements, but it is used and lost to space at rates faster than it is generated. Because of this and its extensive applications in scientific technologies, scientists continue to seek avenues for its exploration, storage, and recycling.

25 million pounds of beads are distributed every Mardi Gras, leading to environmental concerns

The necklaces—which are mostly made from cheap, often toxic, plastic—are believed to be harmful to New Orleans and its residents. Dr. Howard Mielke, an environmental scientist at Tulane University, found that the majority of lead in the city's soil can be found along Mardi Gras parade routes.

The world's biggest silver producers, mapped

Mexico, with its deep history of silver mining, is the dominant leader in silver production, with over 200 million ounces (as of 2023), with China and Peru in second and third place. The precious metal is increasingly important for the electronics industry, and its price is expected to keep rising. See a chart of the biggest silver miners here.

Scientists turn alchemists, transforming transform lead into gold

Fulfilling alchemists' dreams, scientists at the Large Hadron Collider (LHC) transmute lead into gold. While the 86 billion gold nuclei produced were short-lived, the experiment sheds light on how electromagnetic fields can play a critical role in nuclear transmutation.

Many chemicals used in fracking fluid have been classified as toxic

Although the fluid has been known to leach into drinking water supplies, raising health concerns, fracking is exempt from federal clean water regulations due to a loophole in the Energy Policy Act of 2005 championed by former US Vice President Dick Cheney.

Learn about historical uses of bioremediation, the oldest cleanup method on Earth

Biochemical reactions that decompose complex molecules into simpler ones have occurred on Earth for as long as life has existed and have gradually transformed the planet into a celestial body that is increasingly habitable to greater biodiversity. Along the way, modern, human-made bioremediation techniques began to take shape in Santa Maria, California, in the 1960s.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Chromium contaminants in a ruby crystal gave the world's first laser its red color

The red light originates from a long-lasting excited electron state in the element's atomic structure. The brittle gray metal has historically been used in pigment production, the manufacturing of rust-resistant stainless steel, and the creation of durable coatings with long-lasting shine for metals, wood, and leather.

The case against the penny

It takes roughly three cents to produce a single penny, with an annual price tag of nearly $100M. The ubiquitous copper coin is scarcely used, ending up in jars or lost in couches, necessitating even more replacement coins, perpetuating a vicious circle. Studies suggest eliminating the coin would not cost consumers money. See a quick overview of the problem here.

How a single company hooked the world on herbicides

How harmful are today’s herbicides for us humans, and for the environments they’re seeping into? And do we really need weedkillers to feed the world?

See examples of hyperaccumulators, the plants that can harvest heavy metals

These ideal species for phytoremediation possess biochemistry that allows them to absorb and store these elements without being poisoned by their accumulation. Pycnandra acuminata, one such plant, has blue-green sap due to an abundance of nickel, which it captures from the nickel-rich soil in which it grows.

How a Scottish island became awash in forever chemicals—and what it means for other coastal areas

Utility data from 2024 indicates that Fair Isle, Britain's most remote inhabited island, has Scotland's highest level of toxic PFAS—forever chemicals—in its public drinking water. The level is still below Scotland's safety threshold, yet the high levels have confounded scientists and communities because there are no obvious industrial sources on the island. An investigation by The Guardian suggests those chemicals are arriving from thousands of miles away via seaspray and foam. PFAS are persistent pollutants that are chemically attracted to the interface between water and air—meaning there will likely be more of them in seafoam than there may be in the seawater itself.

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

The federal government allowed toxic chemicals into alcohol during Prohibition

Industrial alcohol was still legal during Prohibition, and was often used by bootleggers. In an attempt to disrupt the black market, the government required toxic additives to be included in industrial alcohol, leading to more than one death.

The centuries-old history of titanium white goes back to the Inca

Titanium white can be found in items ranging from paint to pills. Though it was created in New York in 1908, the pigment was first used hundreds of years earlier by the Inca, according to this article.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

The strange endurance of consuming blood for health

Blood's importance to humanity is best summarized this way: without it, we die. This importance naturally begets assumptions about its medicinal properties, many of which appear accessible through drinking or eating the fluid connective tissue. This article details the history of blood drinking, from ancient Roman gladiators to modern-day sanguinarians.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Frank Lloyd Wright's houses are historically hard to sell because they're old, subject to local landmark commissions, and often unfashionable

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

Poison ivy is in the same family as mangoes, cashews, and pistachios—and they all produce oily urushiol in their raw, unprocessed state—but they are typically prepared in ways to avoid causing human discomfort.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Despite being favored by 87% of Americans, Congress does not have term limits.

Cultural norms about how to handle the bodies of loved ones in communities in West Africa have hampered Ebola responses.

The original copy of the Declaration of Independence is not a pristine document, and even features a smudged anonymous handprint in the bottom left corner.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

Double world record holder Hunter Ewen helped conquer his fear of balloons, called globophobia, by training to win Guinness World Record titles for balloon inflation.