24
Mar
Pesticides in Drinking and Irrigation Water in Floriculture Region of Ecuador, Large Exporter of Flowers
(Beyond Pesticides, March 24, 2026) Published in Environmental Pollution, study results in the floriculture region of Ecuador find detections of neonicotinoid insecticides (NNI) and the herbicide atrazine in drinking and irrigation water. The biomonitoring data reported in an earlier journal article in the same region found a total of 23 compounds used as herbicides, insecticides, and fungicides, their associated metabolites (breakdown products), which include organophosphates, pyrethroids, and neonicotinoids. (See Daily News here.) Researchers from the University of Iowa, University of California, San Diego State University, and Universidad de San Francisco in Quito, Ecuador, determined that 1 in 5 households (20.5%) have detectable levels of one or more neonicotinoids in drinking water samples surrounding floricultural agricultural operations. This builds on previous research underscoring the nontarget pesticidal effects in communities near agricultural operations where the chemicals drift through the air and move into soil and water.
Methodology and Results
The authors report that, “This study focused on household tap water in proximity to floricultural plantations and in the ESPINA [Secondary Exposures to Pesticides among Children and Adolescents] participants’ homes with a range of NNI and total pesticides in urinary metabolite samples of the children.” They continue: “Participant households in the water study were selected for household tap water sampling from the ESPINA study based on hotspot analysis for ESPINA children with high levels of pesticides in urinary metabolites together with â€coldspot’ analysis of ESPINA children who had no NNI present in urinary metabolites in 2016.” The data on drinking water for this study were derived in part from a previous study covered by Beyond Pesticides in 2025, with reference to ESPINA.
The researchers also found that 57.6 percent of irrigation water samples had detectable levels of neonic insecticides, which were based on “their proximity to selected ESPINA households.” Across two irrigation channels, there were 26 irrigation samples selected across 2022 and 2023. The older channel runs through areas with a higher concentration of intensive agriculture, with the newer channel running through more rural areas with less intensive agriculture. For further information on the approaches to pesticide analysis, please see Sections 2.4 and 2.5 of the study.
There are several additional notable takeaways from this study:
- Imidacloprid and thiamethoxam were the most frequently detected across the irrigation water samples. The following additional NNIs were detected in one or more samples: clothianidin (6), dinotefuran (1), acetamiprid (3), sulfoxaflor (3), and thiacloprid (2). Atrazine was detected in 3 samples.
- Across the six samples for the non-targeted analysis, 63 contaminants (including insecticides, herbicides, fungicides, and transformation products) were identified, with 39 of those contaminants “confirmed presence by reference standard” across water samples for drinking water and irrigation during 2022.
Previous Coverage
There are numerous examples of peer-reviewed literature that delve into the potential for pesticide drift and associated adverse health and biodiversity effects.Â
When pesticide drift is investigated, it is most often the drift from agricultural fields that is examined. A 2020 study shows that off-target drift of pesticides from greenhouses is also a reality. This research found drift of organophosphate and carbamate pesticides from crop applications in Ecuadoran floriculture greenhouses by evaluating the acetylcholinesterase enzyme (AChE) activity, necessary to the transmission of nerve impulses, in children residing nearby. The team finds that children living in homes near greenhouses in which these insecticides (widely recognized as cholinesterase inhibitors) are used exhibit reduced activity of this enzyme and abnormal functioning of the nervous system. The study analyzes both the distribution of areas of flower crops within “buffer zones” of various sizes around children’s homes, and the “correlation coefficients” (statistical measures of the strength of the relationship between two variables) between household proximity to the nearest treated greenhouse crops and to variously sized areas of flower crops within 1,000 meters of homes. (See Daily News here.)
In analyzing the data present in an article in Data in Brief, concerning levels of pesticide biomarkers present in the urine of adolescents and young adults, which are linked to numerous health implications. The biomonitoring data, collected at two time points from participants in a longitudinal cohort study in the agricultural county of Pedro Moncayo, Ecuador, encompass a total of 23 compounds used as herbicides, insecticides, and fungicides and their associated metabolites (breakdown products), which include organophosphates, pyrethroids, and neonicotinoids.  This study also relies on the ESPINA data, which was initially established in 2008 with a goal “to investigate the impacts of pesticide exposure on development from childhood to adulthood in individuals living within the agricultural community of Pedro Moncayo, Pichincha, Ecuador.” With cut flowers as one of the primary exports from Ecuador, and an emphasis on rose and flower cultivation in Pedro Moncayo, data from this region incorporates exposure to a variety of pesticides from multiple chemical classes. (See Daily News here.)
A 2025 study in Environmental Entomology shows that habitat and open space near agricultural fields become a killing field of pesticides, threatening biodiversity due to contamination from toxic drift. The study detected 42 pesticides, including several neonicotinoids, which are among the most lethal threats to pollinators. The research reveals the complexity of pesticide flow through the environment and the inadequacy of current methods of protecting nontarget organisms, including honey bees, bumblebees, and hundreds of other species of native bees worldwide. The researchers on the study, from the U.S. Department of Agriculture, Cornell University, and Michigan State University, put silicone bands on fence posts in open areas adjacent to highbush blueberry fields on 15 farms in western Michigan. Silicone takes up chemicals in the atmosphere, which can then be extracted and analyzed. The fence posts were placed at seven intervals ranging from zero to 32 meters from the blueberry field edges. They were left in place for three weeks in July 2020. (See Daily News here.) In a novel, continent-wide study of soil biodiversity throughout Europe published in Nature earlier this year, researchers find 70% of the sampled sites contain pesticide residues, which “emerged as the second strongest driver of soil biodiversity patterns after soil properties,” particularly in croplands. (See Daily News here.)
In terms of waterways in the United States, pesticide drift is of concern to various researchers. One example includes a multidisciplinary team of researchers at the University of Connecticut, finding that 46% of Connecticut waterway samples are contaminated with levels of the neonicotinoid insecticide, imidacloprid, one of the most widely used insecticides in the United States on lawn and golf courses. The authors relied on federal data from the U.S. Environmental Protection Agency (EPA) and the U.S. Geological Survey (USGS), state-level data from the Connecticut Department of Energy and Environmental Protection (CT-DEEP), and a small-scale data collection study by the Clean Rivers Project funded by the nonprofit Pollinator Pathway, Inc. In their report, Neonicotinoids in Connecticut Waters: Surface Water, Groundwater, and Threats to Aquatic Ecosystems, the researchers provide the most comprehensive view to date of neonicotinoid levels in Connecticut and offer critical recommendations for future testing within the state and nationally, given glaring data gaps. (See Daily News here.)
Pesticide contamination has also been found to drift from the field into the home. A study published in Environmental Science and Technology finds that there are 47 current-use pesticides—products with active ingredients that are currently registered with the U.S. Environmental Protection Agency (EPA) —detected in samples of indoor dust, drinking water, and urine from households in Indiana. The herbicides (13) detected include 2,4-D (2,4-dichlorophenoxyacetic acid), Alachlor, Atrazine, CIAT (Desethyl-atrazine), Diuron, Metolachlor, Metolachlor OA (Oxanilic acid), OIAT (2-Hydroxy-4-isopropylamino-6-amino-s-triazine), OIET (2-Hydroxyatrazine), Prometon, Simazine, Acetochlor, and Acetochlor OA; the insecticides (20) include neonicotinoids (Acetamiprid, Clothianidin, Dinotefuran, Imidacloprid, Thiacloprid, Thiamethoxam, NDMA [N-desmethyl-acetamiprid], and 6-CNA [6-Chloronicotinic acid]), organophosphates (Diazinon, Ethoprophos, Malathion, IMPY [2-isopropyl-4-methyl-6-hydroxypyrimidine], PNP [p-nitrophenol], and TCPγ [3,5,6-trichloro-2-pyridinol]), pyrethroids (3-PBA [3-Phenoxybenzoic acid], 4-F-3-BA [4-Fluoro-3-phenoxybenzoic acid], and Fenpropathrin), and phenylpyrazoles (Fipronil, Fipronil sulfone, and Desulfinyl fipronil); and the fungicides (9) detected include azoles (Myclobutanil, Propiconazole, Tebuconazole, and Metconazole), strobilurins (Azoxystrobin and Pyraclostrobin), amides (Boscalid and Metalaxyl), and the benzimidazole Carbendazim. (See Daily News here.)
Call to Action
You can continue to stay apprised of the most pressing developments on various issues and campaigns by signing up for Weekly News Update and Action of the Week—including a call to tell your governor to adopt policies that support organic land management and ecological balance. There are also two additional actions you can take to help move practices and policy away from chemical-intensive farming in 2026:
- Petition—Tell Food Companies to Reject GMO Wheat!
- Tell Congress to instruct USDA to prohibit HB4 wheat and instruct EPA to prohibit the use of glufosinate herbicides on wheat.
It should be noted that both pesticides targeted for evaluation in this study are endocrine disruptors, which calls into question the regulatory standards that do not take into account adverse effects well below established threshold levels of exposure. Despite a Congressional mandate in 1996 under the Food Quality Protection Act (FQPA) mandating that EPA establish a protocol for endocrine-disrupting testing of pesticides, the agency has never promulgated a regulatory protocol for testing.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Environmental Pollution
