Glyphosate and AMPA concentrations in wind‐blown material under field conditions

Abstract

Agricultural intensification in fragile arid and semiarid environments has led to an increase in soil degradation, mainly through wind erosion. Argentina is an agricultural and cattle‐farming country, which has increased its productivity in the last few decades, widening the boundaries of farm land and the use of herbicides to control weeds. Glyphosate, which accounts for 65% of the Argentinian pesticides market, is strongly retained in soil. The World Health Organization concluded that there was evidence to classify glyphosate as ‘probably carcinogenic to humans.’ In this context, the objective of this study was to determine the presence and concentration of glyphosate and aminomethylphosphonic acid (AMPA) in wind‐blown material in 3 areas in Argentine semiarid regions (Chaco, La Pampa, and San Luis). In 1‐ha2 plots, left uncovered and levelled, the wind‐blown material was collected at heights of 13.5, 50, and 150 cm during 18 erosion events. The wind‐blown material carried by the wind at a height of 150 cm had concentrations of 247 and 218 μg kg−1 of glyphosate and AMPA, respectively. This material was enriched 60 times in glyphosate and 3 times in AMPA as compared with the original soil. This shows that the eroded material can, potentially, have a negative impact on the ecosystem and also on human health, depending on the proportion of this material released into the atmosphere in suspension as particulate matter. This study is, to our knowledge, the first to report concentrations of glyphosate and AMPA in wind‐blown material under field conditions.

Pesticides in water sources used for human consumption in the semiarid region of Argentina

“…Additionally, during the second and third sampling year a larger area of wheat was sown: the increase was greater than 100% between the first season and the next two. This crop implies a lower use of herbicides than winter fallow and reduces the environmental movement of pesticides by reducing erosion since it generates coverage in the season of stronger winds and decreases wind erosion, which is responsible for displacing soil particles enriched with glyphosate and AMPA [32]. Finally, due to the emergence of resistant weeds and spot spray systems, there is a downward trend of applied doses although the number of applications per year remains constant.…”

“…In semiarid areas, wind erosion plays an important role since the risk of transporting glyphosate and AMPA with suspended dust is very high and they hardly decompose under dry soil conditions [38]. Aparicio et al [32] analyzed sediments collected in the province of Chaco, Argentina, and found 0.66-313 µg kg −1 of glyphosate and 1.3-83 µg kg −1 of AMPA, confirming that wind-eroded material can contribute to water pollution. Furthermore, glyphosate reaching the atmosphere through drift or wind erosion can be washed away by rain.…”

Glyphosate and aminomethylphosphonic acid (AMPA) behavior in loess soils and off‐site transport risk assessment

“…Glyphosate and AMPA are frequently reported to occur in surface water (Okada et al, 2018;Primost et al, 2017;Jayasumana et al, 2015;Battaglin et al, 2014;Aparicio et al, 2013;Hanke et al, 2010;Battaglin et al, 2009;Botta et al, 2009;Struger et al, 2008;Scribner et al, 2007;Kolpin et al, 2006;Battaglin et al, 2005;Humphries et al, 2005;Scribner et al, 2003), streambed sediment (Primost et al, 2017;Battaglin et al, 2014;Aparicio et al, 2013;Peruzzo et al, 2008) and suspended matter (Okada et al, 2018;Primost et al, 2017;Aparicio et al, 2013). Despite their low potential for leaching and low volatility, they have also been reported to occur in groundwater (Okada et al, 2018;Jayasumana et al, 2015;Battaglin et al, 2014;van Stempvoort et al, 2014;Sanchís et al, 2012;Scribner et al, 2007;Brüsch, 2006), rainwater (Battaglin et al, 2014;Chang et al, 2011;Scribner et al, 2007;Humphries et al, 2005;Quaghebeur et al, 2004) and atmospheric dust (Aparicio et al, 2018;Chang et al, 2011;Humphries et al, 2005).…”

“…Although the atmospheric transport of glyphosate and AMPA associated to the particle phase seems extremely likely, studies focusing on their transport with wind erosion are lacking. In fact, just very recently one study was published on the transport of glyphosate and AMPA with wind-blown material under field conditions, indicating high concentrations of these compounds in the dust of agricultural regions of Argentina (Aparicio et al, 2018).…”

“…Besides, the loess region of Córdoba province is prone to wind and water erosion (Apezteguía et al, 2009). However, except for the very recent study of Aparicio et al (2018) on the transport of glyphosate and AMPA with wind-blown sediment, studies on these transport pathways in Argentina are missing. 3 Location of Córdoba province, Córdoba city and study area, and characterization of the province and study area by soil type, geomorphology, hydrography, agricultural use, mean annual precipitation and mean annual temperature in the summer (January) and winter (July) (adapted from Cruzate et al, 2008) 2.…”