Earth from space.
Credit: © Vadimsadovski / Fotolia
Humans have so profoundly altered Earth that, some scientists argue, our current geologic epoch requires a new name: the Anthropocene. But defining the precise start of the era is tricky. Would it begin with the spread of domesticated farm animals or the appearance of radioactive elements from nuclear bomb tests? Scientists report in ACS’ Environmental Science & Technology a method to measure levels of human-made contaminants in sediments that could help pinpoint the Anthropocene’s onset.
The researchers applied high-resolution mass spectrometry to investigate synthetic chemical contamination in two lakes in Central Europe. They examined 1-meter long cores from each lake bottom, capturing the past 100 years of sediment layers. According to the analysis, the lakes’ sediments contained few synthetic contaminants before the 1950s. But during the 1950s, concentrations of industrial chemicals started to appear in the samples, which is consistent with the boom in industrial activities post-World War II. The researchers say this record clearly demonstrates the beginning of large-scale human impact on the environment. It also shows a decline in contamination following the installation of wastewater treatment plants in the 1970s, providing evidence for successful mitigation measures. Additionally, the introduction of new pollutants that are now finding their way into surface waters can be discovered.
Story Source: Materials provided byUniversity of Chicago Original written by Whitney Clavin.Note: Content may be edited for style and length.
Journal Reference:
Aurea C. Chiaia-Hernández, Barbara F. Günthardt, Martin P. Frey, Juliane Hollender. Unravelling Contaminants in the Anthropocene Using Statistical Analysis of Liquid Chromatography–High-Resolution Mass Spectrometry Nontarget Screening Data Recorded in Lake Sediments. Environmental Science & Technology, 2017; DOI: 10.1021/acs.est.7b03357