Bacteria in lead contaminated soil.
Reichard, Larry
Lead is a serious hazard to health, seeing as it is able to
interfere with enzyme activity. Lead may accumulate in soil, posing as a
hazard for children who come in contact. If a child is exposed to high,
bioavailable levels, mental retardation can occur. Missouri has a
problem with lead as a result of mining and smelting. The lead from
these activities may be in several forms, some more toxic than the
others. Land that is left untreated will continue to be hazardous for
many years. Bacterial populations are also susceptible to lead. By
looking at the populations of contaminated soil, we hope to see the
effect of mining and smelting waste on living organisms. We looked at
soil from near a lead mining activity. Lead contamination was 4,000
parts per million. We used several methods to assess the bacterial
populations. After isolating single bacterial colonies on several kinds
of compatible agar, we were able to gram stain all samples. Then we
classified each bacterial sample under the microscope and found several
different cocci, rods, and spirochetes. One bacterial strain we were
able to decipher was Pseudomonas fluorescens. Although other bacteria
were more difficult to identify, some other methods used to aid in
classifying each bacterial sample were performed, including the oxidase
test, catalase test, and stab cultures.
* Laflamme, C.L., L. Kulhanek, and T. Giblin. Department of Natural
Sciences, Stephens College.
