Arsenic compounds

Arsenic powder has been the poisoner's choice since Nero's day. Yet chemists through the ages have formulated less toxic arsenic compounds into artist's colors and dyes, glass, alloys of lead, copper and brass, pesticides, cosmetics, tonics and even medicines.

But no arsenic concoction is without risk. Some scholars theorize that Paris green, a once-popular arsenic-based wallpaper pigment, caused Napoleon's mysterious demise in 1821. In the late 19th century, Italian scientist Bartolomeo Gosio linked the deaths of more than 1,000 children to arsenic vapors from moldy green wallpaper. In 1887, British physician Jonathan Hutchinson reported that arsenic-based medications for syphilis, asthma and psoriasis caused skin cancer.

In 1980, the National Toxicology Program's first Report on Carcinogens listed inorganic arsenic compounds as known human carcinogens. Inorganic arsenic-based pesticides were banned in the years that followed. By 1985, the U.S. had stopped producing arsenic.

Still, America remained the world's leading arsenic consumer, with imports soaring from 14,200 metric tons in 1985 to 25,000 tons by 2001, according to the U.S. Geological Survey.

Some 86 to 90 percent of imports were being made into chromated copper arsenate (CCA), a wood preservative for "pressure-treated" decking, landscaping, walkways, picnic tables and playground equipment. The rest went into semiconductors, specialized metal, a few remaining pesticides and treatments for acute leukemia and other cancers.

In 2001, the Environmental Working Group launched its Poisoned Playgrounds initiative to build support for a ban on arsenic in all consumer products. In November 2001, an EWG analysis entitled The Poisonwood Rivals found that pressure treated wood sold by The Home Depot and Lowe's Home Improvement Warehouse leached as much as1,020 micrograms of pure arsenic -- 100 times the U.S. Environmental Protection Agency's 10 microgram "allowable daily exposure level" for drinking water -- onto a moistened wipe the size of a four-year-old's hand.

On February 12, 2002, under pressure by consumers, members of congress and the EPA, the wood industry agreed to stop using arsenic-based wood preservatives as of December 2003. By 2006, US consumption of arsenic had dropped more than 300 percent. That year, the EPA attempted to ban all arsenic-based pesticides. The proposed regulation is still tied up in regulatory wrangles. Consequently, organic arsenic herbicides are still in use on cotton and turf, including golf courses, lawns, school yards, athletic fields, and rights-of-way.

Many older outdoor wooden structures still contain arsenic. To find out if your wooden deck, picnic table, or playset is leaching the chemical, click here for a test kit order form.