Pesticides and nitrate in groundwater underlying citrus croplands, Lake Wales Ridge, central Florida, 1999-2005.

Choquette, Anne F.

doi:10.3133/ofr20131271

Cited by 7 publications

(9 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Laboratory studies on imidacloprid soil sorption and degradation conducted by Leiva et al [ 20 ], as well as miscible displacement experiments have shown that imidacloprid is a weakly-sorbed (K OC range 163–230) and persistent chemical (t 1/2 range 1.0–2.6 years) during transport in plants in sandy flatwoods soils of Florida [ 21 ]. Moreover, evidence of imidacloprid leaching to groundwater at μg L -1 concentrations have been found in wells located at the Florida Central Ridge [ 22 , 23 ]. In general, soil-drenched systemic pesticides need to be evaluated in the field according to formulation, application rates, and irrigation management.…”

Section: Introductionmentioning

confidence: 99%

Imidacloprid soil movement under micro-sprinkler irrigation and soil-drench applications to control Asian citrus psyllid (ACP) and citrus leafminer (CLM)

et al. 2018

View full text Add to dashboard Cite

Imidacloprid (IM) is used to control the Asian Citrus Psyllid (ACP) and citrus leafminer (CLM), which are related to the spread of huanglongbing (HLB or citrus greening) and citrus canker diseases, respectively. In Florida citrus, imidacloprid is mainly soil-drenched around the trees for proper root uptake and translocation into plant canopy to impact ACP and CLM. The objective of this study was to determine the effect of imidacloprid rate, and irrigate amount on concentration of imidacloprid in the soil following drench application to citrus trees in three age classes. The plots were established at the Southwest Florida Research and Education Center, Immokalee, using a randomized complete-block design for three age classes of trees: one-year-old trees (B1), three to five-year-old trees (B2), and eight-year-old trees (B3). The treatments were a combination of two rates each of imidacloprid (1D, 2D) and micro-sprinkling irrigation (1I, 2I). Imidacloprid and bromide (Br-) used as tracer were applied simultaneously. Soil moisture and concentrations of imidacloprid and Br were monitored using soil cores from hand held augers. Soil moisture content (θV) did not differ under two irrigation rates at any given observation day or depth, except following heavy rainfall events. Br- was lost from the observation depths (0–45 cm) about two weeks after soil-drench. Contrarily, imidacloprid persisted for a much longer time (4–8 weeks) at all soil depths, regardless of treatment combinations. The higher retardation of imidacloprid was related to the predominantly unsaturated conditions of the soil (which in turn reduced soil hydraulic conductivities by orders of magnitude), the imidacloprid sorption on soil organic matter, and the citrus root uptake.Findings of this study are important for citrus growers coping with the citrus greening and citrus canker diseases because they suggest that imidacloprid soil drenches can still be an effective control measure of ACP and CLM, and the potential for imidacloprid leaching to groundwater is minimal.

show abstract

Section: Introductionmentioning

confidence: 99%

Imidacloprid soil movement under micro-sprinkler irrigation and soil-drench applications to control Asian citrus psyllid (ACP) and citrus leafminer (CLM)

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Therefore, direct applications of IMD to the soil surface (and citrus root zone) to control the ACP generate questions about uptake efficiency by the crop, persistency within the root-zone, and potential leaching into groundwater in landscapes such as the Florida Central Ridge and Florida Flatwoods, where most citrus commodities are grown. In fact, IMD was found at μg L -1 levels in 13% of the groundwater monitoring wells, where sandy soils with low organic matter dominate the landscape in Florida [ 14 , 15 ]. It is important to understand IMD soil sorption and transport patterns in these soils to promote management practices that reduce potential for IMD leaching below the citrus root-zone.…”

Section: Introductionmentioning

confidence: 99%

Imidacloprid transport and sorption nonequilibrium in single and multilayered columns of Immokalee fine sand

et al. 2017

View full text Add to dashboard Cite

Imidacloprid (IMD) is a neonicotinoid pesticide soil-drenched to many crops to control piercing-sucking insects such as the Asian citrus psyllid (ACP). Neonicotinoids are persistent in the environment and transport analyses are helpful estimate leaching potential from soils that could result in groundwater pollution. The objective of this study was to analyze IMD breakthrough under saturated water flow in soil columns packed with three horizons (A, E, Bh) of Immokalee Fine Sand (IFS). Also, we used the dimensionless form of the convective-dispersive model (CD-Model) to compare the optimized transport parameters from each column experiment (retardation factor, R; fraction of instantaneous-to-total retardation, β; and mass transfer coefficient, ω) with the parameters obtained from sorption batch equilibria and sorption kinetics. The tracer (Cl-) breakthrough curves (BTCs) were symmetrical and properly described by the CD-Model. IMD BTCs from A, Bh, and multilayered [A+E+Bh] soil columns showed steep fronts and tailing that were well described by the one-site nonequilibrium (OSNE) model, which was an evidence of non-ideal transport due to IMD mass transfer into the soil organic matter. In general, IMD was weakly-sorbed in the A and Bh horizons (R values of 3.72 ± 0.04 and 3.08 ± 0.07, respectively), and almost no retardation was observed in the E horizon (R = 1.20 ± 0.02) due to its low organic matter content (0.3%). Using the HYDRUS-1D package, optimized parameters (R, β, ω) from the individual columns successfully simulated IMD transport in a multilayered column mimicking an IFS soil profile. These column studies and corresponding simulations agreed with previous findings from batch sorption equilibria and kinetics experiments, where IMD showed one-site kinetic mass transfer between soil surfaces and soil solution. Ideally, sandy soils should be maintained unsaturated by crop irrigation systems and rainfall monitoring during and after soil-drench application. The unsaturated soil will increase IMD retardation factors and residence time for plant uptake, lowering leaching potential from soil layers with low sorption capacity, such as the E horizon.

show abstract

“…Aldicarb sulfone and aldicarb sulfoxide have been detected in surficialaquifer wells, with concentrations of 6.30 μg/L and 6.85 μg/L, respectively. 39 The detected concentration was 5−6 times lower than DWEL. Previous study in rats showed that the noobserved adverse effect level (NOAEL) of aldicarb was 0.3 mg/kg/day in a reproductive bioassay and 1.0 mg/kg/day in developmental toxicity bioassay.…”

Section: ■ Discussionmentioning

confidence: 59%

“…The calculation was based on 60 kg adult, 3.7 L daily water consumption, human to mice conversion factor 12.3, and a safety factor of 10. Aldicarb sulfone and aldicarb sulfoxide have been detected in surficial-aquifer wells, with concentrations of 6.30 μg/L and 6.85 μg/L, respectively . The detected concentration was 5–6 times lower than DWEL.…”

Section: Discussionmentioning

confidence: 89%

The Carbamate Aldicarb Altered the Gut Microbiome, Metabolome, and Lipidome of C57BL/6J Mice

Gao

Chi

et al. 2018

Chem. Res. Toxicol.

View full text Add to dashboard Cite

The gut microbiome is highly involved in numerous aspects of host physiology, from energy harvest to stress response, and can confer many benefits to the host. The gut microbiome development could be affected by genetic and environmental factors, including pesticides. The carbamate insecticide aldicarb has been extensively used in agriculture, which raises serious public health concerns. However, the impact of aldicarb on the gut microbiome, host metabolome, and lipidome has not been well studied yet. Herein, we use multiomics approaches, including16S rRNA sequencing, shotgun metagenomics sequencing, metabolomics, and lipidomics, to elucidate aldicarb-induced toxicity in the gut microbiome and the host metabolic homeostasis. We demonstrated that aldicarb perturbed the gut microbiome development trajectory, enhanced gut bacterial pathogenicity, altered complex lipid profile, and induced oxidative stress, protein degradation, and DNA damage. The brain metabolism was also disturbed by the aldicarb exposure. These findings may provide a novel understanding of the toxicity of carbamate insecticides.

show abstract

Pesticides and nitrate in groundwater underlying citrus croplands, Lake Wales Ridge, central Florida, 1999-2005.

Cited by 7 publications

References 11 publications

Imidacloprid soil movement under micro-sprinkler irrigation and soil-drench applications to control Asian citrus psyllid (ACP) and citrus leafminer (CLM)

Imidacloprid soil movement under micro-sprinkler irrigation and soil-drench applications to control Asian citrus psyllid (ACP) and citrus leafminer (CLM)

Imidacloprid transport and sorption nonequilibrium in single and multilayered columns of Immokalee fine sand

The Carbamate Aldicarb Altered the Gut Microbiome, Metabolome, and Lipidome of C57BL/6J Mice

Contact Info

Product

Resources

About