Antibiotic-Resistent Genes Increase

Union of Concerned Scientists, Food & Environment Electronic Digest - February 2010. Read FEED online.

3. Antibiotic-resistance genes in environment are increasing. The number of genes for antibiotic resistance in soil microbes has significantly increased over the past 70 years. A team of British scientists tested samples of benign and disease-causing bacteria from a soil archive in the Netherlands that dates back to 1940, the era when antibiotic use became common. Genes that confer resistance significantly increased over time, for every antibiotic drug class they tested. Genes that confer resistance to tetracycline antibiotics are 15 times more abundant in current-day soil samples than in samples even from the 1970s. Levels of resistance rose in spite of improved waste management practices and the Dutch policy restricting nontherapeutic antibiotic use in agriculture, which is tougher than that of many other countries including the United States. The team concluded that environmental levels of antibiotic-resistance genes are probably still increasing in similar locations worldwide. Read the study abstract in Environmental Science and Technology.