Paper Money is poison: Worldwide it Contains Bisphenol A

The cash register receipts that people place near paper money in billfolds, purses, and pockets has led to a worldwide contamination of paper money with bisphenol A (BPA),a potentially toxic substance found in some plastics, thermal paper and other products.

The amounts of BPA on dollars, Euros, rubles, yuans, and other currencies, are higher than in house dust, but human intake from currency is at least 10 times less than those from house dust.

That's the conclusion of a new study in the ACS' journal Environmental Science & Technology.

Kurunthachalam Kannan and Chunyang Liao point out that manufacturers use BPA to make polycarbonate plastics used in some consumer products, including water bottles, sports equipment, and household electronics.

Studies indicate that BPA acts as an endocrine disruptor -- meaning it mimics the action of the sex hormone estrogen. Exposure to BPA has been linked to a variety of health problems. Although a recent study found traces of BPA in U.S. currency, nobody knew until now about BPA in paper money worldwide.

The scientists' analysis of 156 pieces of paper money from 21 countries found that all contained traces of BPA. The report notes, however, that "estimated daily intake from paper currencies were 10-fold lower than those reported from exposures due to [indoor] dust ingestion in the United States."

The highest BPA levels were in paper money from Brazil, the Czech Republic and Australia, while the lowest occurred in paper money from the Philippines, Thailand, and Vietnam. Levels in U.S. notes were about average.

Kannan and Liao also found that the most likely source of the BPA in the currency is the thermal paper used in cash register receipts. They showed that receipts can transfer BPA onto cash when placed next to it or when a receipt is touched before handling currency.

"Although high levels of BPA were measured in paper currencies, human exposure through dermal [skin] absorption appears to be minor," the article notes.

Synthetics and Biology: Is it a working Partnership?

"Plastics" may have been the Baby Boomer watchword, but "synthetic" rules today.

That's "synthetic" as in synthetic biology, the hottest biomedical buzzword, promising new drugs, new fuel and someday, new life.

"If we can make life, then we understand it," says molecular biologist Steven Benner of the Foundation for Applied Molecular Evolution in Gainesville, Fla.

Starting with the building blocks of animal and plant cells, synthetic biologists are reengineering living things today and hope to create synthetic life tomorrow. The ultimate goal, Benner says, is "synthesizing life from scratch."

That makes experts, including human genome pioneers Craig Venter of Rockville, Md., and Jay Keasling of the University of California-Berkeley, hopeful and cautious at the same time about the promise and peril of the field.

In July, a team led by Carole Lartigue of the J. Craig Venter Institute in Rockville, Md., reported the field's latest advance in the journal Science: a way to genetically engineer bacteria, previously considered impossible. "Nobody else has done anything remotely like this before," Venter says.

The immediate application is engineering defanged vaccine strains for use against the bacteria family chosen for the study. But a lot of other ideas are cooking, from saving the planet from global warming to figuring out just how life started in the first place.

The promise

In 1974, oncologist Wac{lstrok}aw Szybalski of the University of Wisconsin Medical School in Madison coined the term "synthetic biology" as a way to describe biologists shuffling genes among organisms. The term has taken on multiple meanings since then in science, says David Rejeski of the Synthetic Biology Project at the Woodrow Wilson International Center for Scholars in Washington, D.C. The public largely has no clue, he says: "Nobody really knows what it is."

One popular definition championed by MIT's Drew Endy, who founded the non-profit Biobrick Foundation, is an engineering one, in which the parts of cells act as the screws, bolts, bricks and mortar of future biology. Others, such as Venter and Harvard's George Church, talk of building completely man-made cells, with parts all made from scratch.

Some recent innovations:

• Last year, Keasling's lab unveiled bacteria that make the anti-malaria drug artemisinin by transferring 14 genes into a microbe.

• Benner's lab has created an artificial form of DNA that uses six chemicals for the "bases" of a genetic code, unlike the four found in human DNA.

• In March, Church announced the creation of artificial "ribosomes," cellular factories that take messenger genes and make proteins that keep cells alive.

"Over the next 25 years, synthetic biologically engineered antibiotics could be developed which monitor the adaptation of the bacteria they are designed to kill, and modify their response accordingly," says Richard Kitney of the United Kingdom's Imperial College. "Similarly, synthetically engineered T-cell (immune cell) components could be used to develop a device which is capable of finding and killing cancerous cells."