PRESENCE OF THE tetA GENE IN BACTERIA FROM SOIL IRRIGATED WITH GREYWATER CONTAINING TRICLOSAN

Open Access
Author:
Felker, Jill Marie
Graduate Program:
Environmental Pollution Control
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 23, 2011
Committee Members:
  • Dr Katherine Baker, Thesis Advisor
  • Katherine H Baker, Thesis Advisor
Keywords:
  • triclosan
  • greywater
  • tetA gene
Abstract:
Products with triclosan are being used in great amounts. The overuse and misuse of triclosan products may be influencing bacteria to have cross-resistance to antibiotics, such as tetracycline. Hand soaps and toothpastes are common triclosan-laced products with residues that are discharged into household greywater. Environmental studies are needed to assess the effects of triclosan on microbial soil communities, when the soil is irrigated with greywater containing triclosan. This study helps fulfill missing environmental data, by determining if the presence of the tetA gene in bacteria in soil is influenced by triclosan. This study may be the first to examine the possible increase of antibiotic resistant microorganisms associated with the use of greywater used for irrigation. The tetA gene in soil bacteria was isolated, amplified by PCR, and detected by electrophoresis, in this study. There was a significant increase in the presence of the tetA gene in samples irrigated with greywater containing triclosan. This finding suggests that soil bacteria are succumbing to selective pressures and incorporating life sustaining tetA into their genome. Additional testing should be done with larger sample sizes and additional tet gene sequences.