2023 ACS Presentation - Soil column leaching of [14C]-Atrazine in similar soils representing three continents

The OECD 312 Guideline ‘Leaching in Soil Columns’ and the EPA Guideline OCSPP 835.1240 ‘Leaching Studies’ define the mobility of an organic chemical in soil. Laboratory-scale designs described in these guidelines and field lysimeter studies have been used successfully for years to identify potential groundwater contamination and other waterways.  Column leaching studies often use a reference compound with known mobility to establish a relative mobility factor (RMF) of the test chemical.  Atrazine is a typical reference compound used for such a measurement.  Atrazine is still one of the most  widely used herbicides to combat unwanted grasses and broad-leaf weeds globally.

This study compares the leaching potential of [¹⁴C]-atrazine in similar agricultural soils representing three different continents to highlight similarities or differences in leachability between the continents.  The soils used in the study were obtained from North Dakota, USA, Speyer, Germany, and Sao Paulo, Brazil.   Leachability was measured based on the soil column penetration depth, and Koc partition coefficients were estimated using published techniques and further compared to known Koc values for atrazine found in published literature.  These results are compared and discussed, and can be used in future studies employing similar soils.

Dr. Kalumbu Malekani presented this research at the ACS Fall Meeting in San Francisco: