Lead contamination could increase cataracts, blindness risk
By Kathleen Fackelmann, USA TODAY

http://www.usatoday.com/news/health/...ataracts_x.htm

A scientific report released today suggests that older men with high
lead concentrations in their bodies have a much higher risk of
developing cataracts, the leading cause of blindness.

This is the first large study to show that lifetime exposure to lead in
the environment might play a role in the formation of cataracts, a
clouding of the eye's lens.

The findings suggest that there might be ways to reduce the risk of
cataracts, a condition once thought to be an inevitable part of growing
older, says Howard Hu, one author of the study. The report appears in
today's Journal of the American Medical Association.

In the USA, that reduction would not only preserve the vision of many
older Americans, but it also would reduce the burden on the federal
Medicare program, which already pays a huge amount for the treatment of
cataracts, says George Cioffi, a spokesman for Prevent Blindness America.

The effect would be greater in developing nations, where manufacturing
plants still spew lead into the environment — and where people often
don't have access to a vision-sparing cataract operation, Cioffi says.

Since the late 1970s, the United States has phased out or banned lead in
gasoline and in many household products. But adults who grew up from the
1950s through the 1970s were exposed to lead in the environment.

Lead was stored away in the bodies of people who ingested or inhaled it,
and now, decades later, that lead is still there, says Hu, an
environmental medicine expert at the Harvard School of Public Health.

Those stores of lead in the bone and in other tissues are thought to
leak out over time, which can damage the body's organs. But lead's
effect on the eye was not known.

Hu, Debra Schaumberg of the Brigham and Women's Hospital and their
colleagues studied 642 men ages 60 and older. The researchers first
measured the amount of lead in the bones and then conducted periodic eye
examinations.

They discovered that men with the highest levels of lead had a nearly
threefold risk of developing cataracts. "Lead may contribute to 42% of
cataract cases," Hu says. "That's huge."

Although the study focused only on men, the researchers believe that the
risk applies to women as well. Schaumberg said the team will conduct a
study involving women soon.

More than half of all people age 80 and older have cataracts. But the
researchers believe that lead might make this age-related problem worse.
Lead could exacerbate the age-related oxidative damage that afflicts the
body, including cells of the eye, Hu says. As time goes on, that damage
can lead to a clouding of the lens and loss of vision.

The findings suggest that more can be done in the USA to reduce exposure
to lead, Hu says. He notes that people still drink water drawn from
leaded pipes and are exposed to deteriorating paint in older homes.
Homes built before 1980 often have lead-based paint.

People, especially children, can ingest or inhale lead when the paint
flakes off and mixes with dust, Hu says.

Older Americans can't get rid of the lead their bodies have stored over
a lifetime, but they might be able to reduce lead's damaging effects
with a diet heavy in fruits and vegetables. Fruits and vegetables
contain nutrients that might help reduce oxidative damage to the eye, Hu
says.