In artisanal gold mining, workers collect silt from crudely dug pits and then add the element mercury to the dirt. Mercury attracts the gold, causing it to lump together. The dirt is then heated, which dissipates the mercury, leaving the gold easier to see and extract.

The method is effective but deadly. Mercury is a toxic metal known to cause brain damage and death. Artisanal miners invariably inhale the fumes. The United Nations Industrial Development Organization estimates 15 million miners and their families are affected by the fumes. Artisanal mining is just one major environmental headache, says the Blacksmith Institute, a New York City-based environmental health group, in a new Top 10 list of the world's worst pollution problems.

In alphabetical order, those problems are: artisanal gold mining; contaminated surface water; contaminated ground water; indoor air pollution; metals smelting and processing; industrial mining; radioactive waste and uranium mining; untreated sewage; urban air quality; and used lead-acid battery recycling.

In some cases, these problems have been solved or diminished in the developed world. But they remain disastrous elsewhere. And, says the Blacksmith group, they're not just problems for folks in Third World countries. The mercury used in a Ghana artisanal gold mine, for example, leaches into the environment, where it can travel through the food chain and through ecosystems until, perhaps, it winds up in a can of tuna eaten by you.

'TRUE FACTS'

Dogs are more likely than humans to yawn when people around them yawn, according to a study conducted at Birkbeck College, University of London.

PRIME NUMBERS

2,200: Amount, in dollars, to rent HAL, a mobility-enhancing robotic exoskeleton, for a month in Japan

26: Number of pearls recently found in one Lebanese oyster

2048: Year, according to a government computer model, in which every American adult will be overweight

Sources: New Scientist; Harper's; Agency for Healthcare Research and Quality

BRAIN SWEAT

In two minutes, how many words can you make out of the word "crazed?"

ELECTRON INK

Got mercury?

gotmercury.org

A service of the Turtle Island Restoration Project, this online calculator estimates your mercury exposure from seafood consumption. Type in your weight, the kind of fish eaten and amount eaten to get a percentage of the maximum mercury exposure recommended by the Environmental Protection Agency. There are also versions in Spanish and for your cell phone.

BRAIN SWEAT ANSWER

We don't have a definitive list, but here are some you might have found: raze, race, razed, raced, zed, daze, read, dare, cared, care, red, dear, ace, aced, are.

PATENTLY ABSURD

Unless, say, you're Tiger Woods, getting distance on your long shots is always a bit of a challenge. And thus, the perceived need for the "jet propulsion golf club," patented in 1999.

Its inventors describe it as "a golf club for impelling a golf ball farther with thrust force assist." We describe it this way: Imagine an ordinary driver hooked up to a high-pressure water pump and tank. You line up for the shot and press a button on the club. Pressurized water from the pump/tank flows through a hose into the club handle, down the hollow shaft and out the back of the striking head, propelling it forward at great speed.

Presumably, spectators are advised not to stand within the water-ejection field; otherwise, the golfer might make a hole in one.

QUIRKS OF NATURE

There's a new record holder for longest bug in the world: a newly discovered stick insect called Phobaeticus chani, which lives in the rain-forest canopy of Borneo. With legs fully stretched, it is 22.3 inches long.

VERBATIM

This will eventually become just another way of communicating.

— Mike D'Zmura, lead researcher on a telepathy project funded by the U.S. Army

To find out more about Scott LaFee and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.