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LEFT: AUGUSTO ZAMBONATO. RIGHT: SCHANKZ/SHUTTERSTOCK

Does This Dust

Make Me Look Fat?

❯ 

DUST BUNNIES may be more than a nuisance that

irritates your allergies and adds to your chore list

— they may also be making you chubby.

House dust is full of pollutants, including industrial

chemicals such as bisphenol A (BPA), that can leach

from containers of household products. Researchers

tested 40 substances commonly found in the home

that they “suspected have some sort of impact on

metabolic health,” says Duke University’s Christopher

Kassotis, a co-author of the study, published in July

in Environmental Science & Technology. Although the

research was limited to mouse cells in a petri dish,

Kassotis says the team found that two-thirds of the

chemicals tested drove fat cells to develop and proliferate.

However, researchers need more testing before we

know the effect on humans — and if we can trade in our

gym memberships for a dust mop.  STEVEN POTTER

❯ 

RUTGERS UNIVERSITY

NEUROSCIENTIST John

McGann, an olfaction researcher,

has long been puzzled by claims that

people have a feeble sense of smell.

In his lab, humans perform as well as

rodents and dogs in some tests. Research

by his colleagues suggests our species

can distinguish a trillion different odors.

In a May review published in Science,

McGann finally sniffed out the source of

the foul-smelling rumor.

The main culprit is Paul Broca, a

leading 19th-century anatomist, who

observed that the brain’s olfactory

bulb — where we detect smells — is

proportionally puny compared with

other mammals. “He accepted the near-

universal belief in human exceptionalism

and looked in the brain for evidence

of it,” says McGann. For Broca, a weak

sense of smell elevated us above brute

animal instinct. His beliefs were adopted

by others — even Sigmund Freud.

What Broca missed, McGann points

out, is that relative bulb size doesn’t

matter. Bigger animals have bigger

noses, but that doesn’t mean they also

need bigger olfactory systems.

When it comes to smell, we’re animals.

And knowing that could help scientists

better understand human behavior,

emotion and even memory.

 JONATHON KEATS

Sniffing Out

the Truth