Evaluation of Monensin Transport to Shallow Groundwater after Irrigation with Dairy Lagoon Water

Abstract

Animal waste products from concentrated animal feeding operations are a significant source of antibiotics to the environment. Monensin, an ionophore antibiotic commonly used to increase feed efficiency in livestock, is known to have varied toxicological effects on nontarget species. The current study builds on prior studies evaluating the impact of dairy management on groundwater quality by examining the transport of monensin in an agricultural field with coarse-textured soils during irrigation with lagoon wastewater. The dairy is located in California's San Joaquin Valley, where groundwater can be encountered <5 m below the surface. Groundwater samples were collected from a network of monitoring wells installed throughout the dairy and adjacent to irrigated fields before and after an irrigation event, which allowed for measurement of monensin potentially reaching the shallow groundwater as a direct result of irrigation with lagoon water. Monensin was extracted from water samples via hydrophilic-lipophilic balance solid-phase extraction and quantified with liquid chromatography-mass spectrometry. Irrigation water was found to contain up to 1.6 μg L monensin, but monensin was only detected in monitoring wells surrounding the waste storage lagoon. Water chemistry changes in the wells bordering the irrigated field suggest that up to 7% of irrigation water reached groundwater within days of irrigation. The study suggests that contamination of groundwater with monensin can occur primarily by compromised waste storage systems and that rapid transport of monensin to groundwater is not likely to occur from a single irrigation event.

Assessing biosynthetic potential of agricultural groundwater through metagenomic sequencing: A diverse anammox community dominates nitrate-rich groundwater

“…Depth to the water table for the monitoring wells was 3.4 m bgs, and the wells were sampled at a depth of 4.3 m bgs. A previous hydrologic analysis indicated that MW5 is primarily recharged from the manured corn field, MW6 receives partial recharge from the manured corn field and partial recharge from an adjacent unmanured orchard, and DOM is primarily recharged from the adjacent orchard with slight impact from the manured field [10–12]. …”

“…We made individual samples of four water sources on July 11, 2012 at a single 1500 cow dairy in Stanislaus County, California. The three wells and the surface lagoon are all located within 500 m of each other horizontally [10]. Groundwater water levels are 4.3 m below surface.…”

Occurrence of Antibiotics in an Agricultural Watershed in South‐Central Idaho

“…Like the excretion of other antibiotics by animals, monensin is readily disseminated on farm and to environments located near agricultural operations. As a result, monensin has been detected in wastewater lagoons, shallow groundwaters, river sediments, and surface waters (Bartelt‐Hunt et al, 2011; Hafner et al, 2016; Kim and Carlson, 2006; Lissemore et al, 2006). In a rainfall simulation study conducted by Davis et al (2006), monensin was reported to have the greatest runoff potential among a mixture of antibiotics (including tetracycline, chlortetracycline, sulfathiazole, sulfamethazine, erythromycin, and tylosin) that was applied to the soil surface.…”

Groundwater Pollution and Vulnerability Assessment

“…Application of wastewater generated at livestock operations facility can potentially add antibiotics to groundwater. A study conducted by Hafner et al (2016) demonstrated the vulnerability of shallow groundwater to antibiotic pollution due to land application of dairy wastewater. The authors stated that ionophore antibiotic monensin is typically used in intensive dairy operations to increase the feed efficiency.…”

“…Groundwater sampling conducted by the authors at a dairy site located in San Joaquin Valley, CA showed that water from dairy lagoon used for irrigation purposes had contaminated the shallow groundwater (depth <5 m) with monensin being detected in wells proximal to the waste storage lagoon (Hafner et al, 2016) Similar instances of occurrence of various pharmaceuticals such as antidepressants (tricyclic antidepressants and antipsychotics), antitussive agent and by-products or precursors were also reported in Olomouc, Czech Republic (Kˇresinová et al, 2016). These findings are based on the analysis of groundwater samples collected from six boreholes located in the industrial locality near Farmak a. s. in Olomouc.…”