Herbicides, antibiotics, stimulants, and disinfectants in agricultural water sources

Authors: PANTHI, SURAJ - University Of Maryland; SAPKOTA, AMY - University Of Maryland; RASPANNTI, GREG - University Of Maryland; ALLARD, SARA - University Of Maryland; BUI, ANTHONY - University Of Maryland; CRADDOCK, HILLARY - University Of Maryland; MURRARY, RIANNA - University Of Maryland; ZHU, LIBIN - University Of Arizona; East, Cheryl - Roberts; Handy, Eric; CALLAHAN, MARY THERESA - University Of Maryland; HAYMAKER, JOSEPH - University Of Maryland Eastern Shore (UMES); KULKARNI, PRACHI - University Of Maryland; ANDERSON, BRIENNA - University Of Delaware; CRAIGHEAD, SHANI - University Of Delaware; GARTLEY, SAMANTHA - University Of Delaware; VANORE, ADAM - University Of Delaware; BETANCOURT, WALTER - University Of Arizona; DUNCAN, RICO - University Of Maryland Eastern Shore (UMES); FOUST, DEREK - University Of Maryland Eastern Shore (UMES); Sharma, Manan; MICALLEF, SHIRLEY - University Of Maryland; GERBA, CHARLES - University Of Arizona; PARVEEN, SALINA - University Of Maryland Eastern Shore (UMES); HASHEM, FAWZY - University Of Maryland Eastern Shore (UMES); MAY, ERIC - University Of Maryland Eastern Shore (UMES); KALMIA, KNIEL - University Of Delaware; POP, MIHAI - University Of Maryland; RAVISHANKAR, SADHANA - University Of Arizona; SAPKOTA, AMIR - University Of Maryland

Submitted to: Environmental Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/12/2019
Publication Date: 4/17/2019
Citation: Panthi, S., Sapkota, A.R., Raspannti, G., Allard, S., Bui, A., Craddock, H., Murrary, R., Zhu, L., East, C.L., Handy, E.T., Callahan, M., Haymaker, J., Kulkarni, P., Anderson, B., Craighead, S., Gartley, S., Vanore, A., Betancourt, W.Q., Duncan, R., Foust, D., Sharma, M., Micallef, S.A., Gerba, C., Parveen, S., Hashem, F., May, E., Kalmia, K., Pop, M., Ravishankar, S., Sapkota, A. 2019. Herbicides, antibiotics, stimulants, and disinfectants in agricultural water sources. Environmental Research. 174:1-8. https://doi.org/10.1016/j.envres.2019.04.011.
DOI: https://doi.org/10.1016/j.envres.2019.04.011

Interpretive Summary: The most common uses of freshwater withdrawals are for agricultural irrigation; with fresh water sources under more and usage stress, non-traditional irrigation waters NTIW) should be evaluated for agricultural use. However, although much attention has been paid to the microbiological safety of non-traditional irrigation water, the chemical safety of these types of waters is less explored. This study examined 202 samples of five different types of NTIW from the Mid-Atlantic and Southwest regions of the U.S. to determine concentrations of herbicides, antibiotics, stimulants, and disinfectants in these waters. Untreated surface water contained the highest concentrations of atrazine (herbicide), oxacillin (antibiotic), and penicillin G (antibiotic). A seasonal effect was observed, with winter months supporting higher concentrations of azithromycin (antibiotic) while high atrazine levels were observed in summer months. The knowledge of the potential chemical health risks of non-traditional irrigation water will benefit farmers by identifying chemical targets for specific mitigation treatments.

Technical Abstract: Agricultural water withdrawals account for the largest proportion of global freshwater use. Increasing municipal water demands and droughts are putting a strain on agricultural water. Therefore, alternative solutions to agricultural water crises are urgently needed, including the use of nontraditional water sources such as advanced treated wastewater or reclaimed water, brackish water, return flows, and effluent from produce processing facilities. However, it is critical to ensure that such usage is protective of public health. Here we characterized five different nontraditional water types (n= 202 samples) for herbicides, antibiotics, stimulants, and disinfectants using an ultra-high-pressure liquid chromatography tandem mass spectrometry based method (UPLC-MS/MS). We then evaluated whether levels of these contaminants were influenced by season. Untreated surface water sources had the highest concentrations of atrazine, oxacillin and penicillin G at 106.9, 188.8 and 214.5 ng/L, respectively. Reclaimed water had the highest levels of antibiotics. Produce processing plant water also tended to have higher levels of atrazine (635.7 ng/L), ciprofloxacin (38 ng/L) and tetracycline (72 ng/L). In addition, we observed seasonal variability, with the highest azithromycin concentrations observed over the winter months, while maximum atrazine levels were observed during the summer months. Further studies are needed to evaluate the effectiveness of economically feasible on-farm water treatment technologies that can effectively remove emerging chemical contaminants from nontraditional irrigation water sources.