is toxic. It’s the dose that makes the poison” says
Dr. Jay Gandolfi to his toxicology class. As Program Director
of the Superfund Basic Research Program at The University of
Arizona, he is interested in finding out exactly when the chemicals
we use become poisons, how we can best live with the poisons
we have created for ourselves, and how we can get rid of them.
There are 15
universities across the United States that have been awarded
Research grants by the U.S. Environmental
Protection Agency. The research done at The University of Arizona
is tailored to address problems associated with the Southwest.
One focus is Arsenic, a major contaminant of drinking water and
dust as a result of its presence in mine tailings throughout the
region. Jay coordinates a number of projects, which work concertedly
to assess the risk posed by environmental Arsenic to people living
in the Southwest; to develop ways of preventing illness and environmental
damage where risks are present; and to repair damage by removing
the contaminant. The scientists of the Superfund are a multidisciplinary
team of biomedical scientists, environmental scientists, and environmental
when contaminants become toxicants Jay is looking at how the
body processes Arsenic.
People have known for centuries
large doses of Arsenic is deadly. The Superfund is investigating
the long-term effects of Arsenic found in drinking water at or
near the federally accepted levels of ten parts-per-billion. Some
forms of arsenic are more toxic than others and some people respond
differently to Arsenic. Jay’s interest in this area is how
the body metabolizes and excretes Arsenic, discovering that once
inside the body Arsenic is chemically modified in a variety of
ways. His research has shown the different compounds and chemical
forms of Arsenic affect organs and cells through a number of ways.
In a study
conducted in the Yaqui Valley in Sonora, Mexico, his team was
able to show
children aged seven to 11 years process Arsenic
in a different way than adults. They think the reason for the difference
adults and children metabolize Arsenic differently is due to a
change that happens with age, in how a particular gene affects
the body’s processing of Arsenic. Importantly this gene variation
is correlated with a high proportion of one of the most toxic forms
of Arsenic in the body. This evidence suggests children may be
particularly sensitive to Arsenic. Simply knowing who is at the
most risk is one of the ways we can prevent the effects of exposure
to a toxin.
Of course Jay is not content to stop here, once he knows that
a danger exists, his interest is in removing it. Bio-engineers
working under the Superfund grant are exploring ways of removing
Arsenic from the mine tailings littered around the Southwest. Knowing
that certain plants can store Arsenic in their roots, the engineers
are exploring ways that plants might be able to prevent Arsenic
from escaping into the watershed. Once Arsenic enters the watershed
it can be consumed by animals and people and become part of the
food chain. Engineers in the project are searching for desert plants
that will grow in the environmental conditions of the Southwest
and can sequester Arsenic. They had planned to grow these plants
on the mine tailings, a source of much of the Arsenic. However,
plants have a symbiotic relationship with the microorganisms in
the soil where they grow, and since the mine tailings contain toxic
Arsenic, the soil there are few microorganisms that can live there.
The challenge faced by the engineers on the project is to come
up with a method to seed the ground with the right microorganisms
so that the plants will survive.
A toxic contaminant is a complicated problem. To identify the
problem, understand its complexities and develop a solution Dr.
Jay Gandolfi must coordinate research scientists and engineers
from different disciplines, working on separate, but related facets
of a grander task. Working together the Superfund multidisciplinary
team has a good chance of overcoming environmental and health problems,
which are important in the Southwest and other parts of the world.