News
Scroll down to read summaries of recent news related to
chemicals, human health, and the environment. Different stories
relate to different units of CHEM-2.
Safety in Your Community
Do you know if there is a chemical
plant in your community? Has there been a chemical
accident in your community
within the last five years? Do you know what to do
if an accident
occurs? If you answered "no" to these questions,
you are like the majority of people in the United States,
according to a study done in 2003 by the State of Texas’ Engineering
Experiment Station's Process Safety Center.
The study
found the top five most released chemicals in the United
States in the last 10 years were: ammonia,
chlorine,
hydrogen, propane and formaldehyde. It said chemical
spills with related injuries and fatalities are probably
declining,
but no one knows for sure because the information is
not nationally tracked.
"
We need to have a better informed public—where
the public trusts the information coming out of the
chemical
industry—so people are better able to deal with
emergencies such as chemical incidents," said
Dr. Sam Mannan, director of the study. "Public
trust is essential for improved safety."
Is Noise
Affecting Your Brain?
Scientists have found
that noise affects the brain development of infant
rats. Researchers at the University
of California,
San Francisco, exposed infant rats to continuous "white
noise." White noise refers to the relatively low-level
continuous sounds in the environment, such as the sound
of electronic equipment or traffic. The noise level
was not
high enough to cause hearing loss, but it did prevent
the rats from hearing normal sounds from the environment
early
in life.
Using electrical probes, researchers were
able to map the organization of the auditory parts
of the rat’s
brain. They found that rats exposed to white noise
early in life
did not have the normal brain organization for sound
that other rats did. However, if the rats were exposed
to normal
sounds later, their brain was able to compensate and
reorganize itself normally. Researchers say the increasing
amount of
white noise in the environment may be why more and
more children are language-delayed or have speech problems
when they are
young.
New Polymer Makes Better Batteries
Everyone uses batteries,
and it can be expensive and time-consuming to replace them
when they run down.
Even rechargeable lithium
batteries only hold their charge for a few days.
Researchers think they have a solution. Chemist Thomas
Luther developed
a polymer membrane he calls "an inorganic
version of plastic kitchen wrap." It allows
the positively-charged ions in a lithium battery
to create an electrical
circuit, but it won’t let the negative ions
pass through. It is the negative ions that are
responsible for batteries
running
down. He estimates his batteries will be able to
sit for 500 hours with no loss of power.
His battery
doesn’t yet generate enough power to
be competitive with regular batteries, but he is
confident that
the problem will soon be solved. The polymer membrane
can be modeled into any shape. It is also very
tolerant of temperature
extremes, so it could be used at temperatures below
freezing, like in space.
Looks Like Sugar,
Tastes Like Sugar…
A new no-calorie sweetener may
be in the food you eat. It sold under the brand
name of Splenda®. It was first discovered
in 1976 and approved for limited use in the United
States in 1998. In July 1999, it received approval
for unlimited
use. Splenda®, or sucralose, is made from sugar.
It is made by replacing three hydrogen–oxygen
groups on the sugar molecule with three chlorine
atoms. This
slight chemical
change means that the human body cannot break it
down. As a result, a person would not get calories
from it.
Since its discovery, there have been more
than 100 scientific studies on it. Causing virtually
no side
effects, it
has been proven to be safe in animal and human
trials. Unlike
other artificial sweeteners, it can be measured
in quantities similar to sugar and stored for long
periods
of time.
It also holds up to heat, which means that it doesn’t
lose its sweetness in cooking.
Some "Experts" Would
Throw Mercury Out with the Trash
In 2001, the American
Academy of Pediatrics recommended that health professionals
and consumers stop using
thermometers or other devices containing mercury.
Mercury is a toxic
element
that can be absorbed through the skin or inhaled
as it vaporizes. The ingestion of even small
amounts can
cause
neurological
damage, particularly in infants and small children.
In
May 2002, researchers at Rutgers University College of
Pharmacy and the University of Medicine
and Dentistry
of
New Jersey asked 80 different groups, including
public health agencies, how mercury thermometers
should
be disposed of.
Only a third of the groups
who might be contacted about or responsible for disposing
of mercury
responded correctly.
Thirty-six groups recommended throwing them
into the trash; 19 said they didn't know
and suggested
calling
someone
else;
and 19 suggested taking the device to a specific
site, such as a hazardous waste center. As
a hazardous waste
that could
contaminate water and food supplies or be
ingested by wildlife, mercury should always be taken
to hazardous waste disposal
facilities.
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