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PloS One 2013The topical toxicities of five commercial grade pesticides commonly sprayed in apple orchards were estimated on adult worker honey bees, Apis mellifera (L.)... (Comparative Study)
Comparative Study
The topical toxicities of five commercial grade pesticides commonly sprayed in apple orchards were estimated on adult worker honey bees, Apis mellifera (L.) (Hymenoptera: Apidae) and Japanese orchard bees, Osmia cornifrons (Radoszkowski) (Hymenoptera: Megachilidae). The pesticides were acetamiprid (Assail 30SG), λ-cyhalothrin (Warrior II), dimethoate (Dimethoate 4EC), phosmet (Imidan 70W), and imidacloprid (Provado 1.6F). At least 5 doses of each chemical, diluted in distilled water, were applied to freshly-eclosed adult bees. Mortality was assessed after 48 hr. Dose-mortality regressions were analyzed by probit analysis to test the hypotheses of parallelism and equality by likelihood ratio tests. For A. mellifera, the decreasing order of toxicity at LD₅₀ was imidacloprid, λ-cyhalothrin, dimethoate, phosmet, and acetamiprid. For O. cornifrons, the decreasing order of toxicity at LD₅₀ was dimethoate, λ-cyhalothrin, imidacloprid, acetamiprid, and phosmet. Interaction of imidacloprid or acetamiprid with the fungicide fenbuconazole (Indar 2F) was also tested in a 1∶1 proportion for each species. Estimates of response parameters for each mixture component applied to each species were compared with dose-response data for each mixture in statistical tests of the hypothesis of independent joint action. For each mixture, the interaction of fenbuconazole (a material non-toxic to both species) was significant and positive along the entire line for the pesticide. Our results clearly show that responses of A. mellifera cannot be extrapolated to responses of O.cornifrons, and that synergism of neonicotinoid insecticides and fungicides occurs using formulated product in mixtures as they are commonly applied in apple orchards.
Topics: Animals; Bees; Dimethoate; Drug Synergism; Fungicides, Industrial; Imidazoles; Insecticides; Lethal Dose 50; Malus; Neonicotinoids; Nitriles; Nitro Compounds; Phosmet; Pyrethrins; Pyridines; Triazoles
PubMed: 24039783
DOI: 10.1371/journal.pone.0072587 -
Acta Crystallographica. Section E,... Jul 2010In the title compound, C(11)H(12)NO(4)PS(2), the dihedral angle between the phthalimidyl ring plane and the PS(2) plane of the phospho-rodithio-ate group is...
In the title compound, C(11)H(12)NO(4)PS(2), the dihedral angle between the phthalimidyl ring plane and the PS(2) plane of the phospho-rodithio-ate group is 60.41 (3)°. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds and S⋯S inter-actions [3.3825 (9) Å] contribute to the stabilization of the packing.
PubMed: 21588425
DOI: 10.1107/S1600536810029338 -
Journal of Exposure Science &... Apr 2019Reducing residential pesticide exposure requires identification of exposure pathways. Compared to the agriculture worker 'take-home' and residential use pathways,...
Reducing residential pesticide exposure requires identification of exposure pathways. Compared to the agriculture worker 'take-home' and residential use pathways, evidence of the 'drift' pathway to pesticide exposure has been inconsistent. Questionnaire data from individuals (n = 99) and dust samples (n = 418) from households across three growing seasons in 2011 were from the For Healthy Kids! study. Summed dimethyl organophosphate pesticide (OP) (Azinphos-Methyl, Phosmet, and Malathion) concentrations were quantified from house dust samples. Spatially-weighted orchard densities surrounding households were calculated based on various distances from homes. Regression models tested associations between orchard density, residential pesticide use, agriculture worker residents, and summed dimethyl OP house dust concentrations. Estimated relationships between orchard density and dimethyl OP in house dust were mixed: a 5% increase in orchard density resulted in 0.3 and 0.5% decreases in dimethyl OP house dust concentrations when considering land-cover 750 m or 1250 m away from households, respectively, but null associations with land-cover 60 m or 200 m away. Dimethyl OP house dust concentrations were 400% higher within homes where at least two residents were agriculture workers. Despite inconclusive evidence for the drift pathway due to potential for bias, relationships between number of agriculture workers and dimethyl OP house dust concentration underscores the take-home pathway.
Topics: Adult; Agriculture; Dust; Environmental Exposure; Female; Housing; Humans; Male; Occupational Exposure; Organophosphorus Compounds; Pesticide Residues
PubMed: 30254255
DOI: 10.1038/s41370-018-0074-5 -
Applied and Environmental Microbiology Jul 2002We isolated a bacterial strain, Agrobacterium radiobacter P230, which can hydrolyze a wide range of organophosphate (OP) insecticides. A gene encoding a protein involved...
We isolated a bacterial strain, Agrobacterium radiobacter P230, which can hydrolyze a wide range of organophosphate (OP) insecticides. A gene encoding a protein involved in OP hydrolysis was cloned from A. radiobacter P230 and sequenced. This gene (called opdA) had sequence similarity to opd, a gene previously shown to encode an OP-hydrolyzing enzyme in Flavobacterium sp. strain ATCC 27551 and Brevundimonas diminuta MG. Insertional mutation of the opdA gene produced a strain lacking the ability to hydrolyze OPs, suggesting that this is the only gene encoding an OP-hydrolyzing enzyme in A. radiobacter P230. The OPH and OpdA proteins, encoded by opd and opdA, respectively, were overexpressed and purified as maltose-binding proteins, and the maltose-binding protein moiety was cleaved and removed. Neither protein was able to hydrolyze the aliphatic OP malathion. The kinetics of the two proteins for diethyl OPs were comparable. For dimethyl OPs, OpdA had a higher k(cat) than OPH. It was also capable of hydrolyzing the dimethyl OPs phosmet and fenthion, which were not hydrolyzed at detectable levels by OPH.
Topics: Amino Acid Sequence; Aryldialkylphosphatase; Cloning, Molecular; Coumaphos; Esterases; Molecular Sequence Data; Phosphoric Monoester Hydrolases; Rhizobium; Sequence Homology, Amino Acid; Structure-Activity Relationship; Substrate Specificity
PubMed: 12089017
DOI: 10.1128/AEM.68.7.3371-3376.2002 -
Plants (Basel, Switzerland) Feb 2024The spotted-wing drosophila, (Matsumura) (Diptera: Drosophilidae), is a pest that reduces the productivity of small fruits. Entomopathogenic nematodes (EPNs) and...
The spotted-wing drosophila, (Matsumura) (Diptera: Drosophilidae), is a pest that reduces the productivity of small fruits. Entomopathogenic nematodes (EPNs) and chemical insecticides can suppress this pest, but the compatibility of the two approaches together requires further examination. This laboratory study evaluated the compatibility of IBCBn 06, IBCBn 02, IBCBn 24, and HB with ten chemical insecticides registered for managing pupae. In the first study, most insecticides at the recommended rate did not reduce the viability (% of living infective juveniles (IJs)) of and both species. The viability of was lowered by exposure to spinetoram, malathion, abamectin, azadirachtin, deltamethrin, lambda-cyhalothrin, malathion, and spinetoram after 48 h. During infectivity bioassays, phosmet was compatible with all the EPNs, causing minimal changes in infectivity (% pupal mortality) and efficiency relative to EPN-only controls, whereas lambda-cyhalothrin generally reduced infectivity of EPNs on pupae the most, with a 53, 75, 57, and 13% reduction in infectivity efficiency among , and , respectively. The second study compared pupal mortality caused by the two most compatible nematode species and five insecticides in various combinations. Both species caused 78-79% mortality among pupae when used alone, and were tested in combination with spinetoram, malathion, azadirachtin, phosmet, or novaluron at a one-quarter rate. Notably, caused 79% mortality on pupae when used alone, and 89% mortality when combined with spinetoram, showing an additive effect. Novaluron drastically reduced the number of progeny IJs when combined with by 270 IJs and by 218. Any adult flies that emerged from EPN-insecticide-treated pupae had a shorter lifespan than from untreated pupae. The combined use of and compatible chemical insecticides was promising, except for novaluron.
PubMed: 38475479
DOI: 10.3390/plants13050632 -
PloS One 2013Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens...
Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee colonies. Such findings are of great concern given the large numbers and high levels of pesticides found in honey bee colonies. Thus it is crucial to determine how field-relevant combinations and loads of pesticides affect bee health. We collected pollen from bee hives in seven major crops to determine 1) what types of pesticides bees are exposed to when rented for pollination of various crops and 2) how field-relevant pesticide blends affect bees' susceptibility to the gut parasite Nosema ceranae. Our samples represent pollen collected by foragers for use by the colony, and do not necessarily indicate foragers' roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and watermelon bees collected pollen almost exclusively from weeds and wildflowers during our sampling. Thus more attention must be paid to how honey bees are exposed to pesticides outside of the field in which they are placed. We detected 35 different pesticides in the sampled pollen, and found high fungicide loads. The insecticides esfenvalerate and phosmet were at a concentration higher than their median lethal dose in at least one pollen sample. While fungicides are typically seen as fairly safe for honey bees, we found an increased probability of Nosema infection in bees that consumed pollen with a higher fungicide load. Our results highlight a need for research on sub-lethal effects of fungicides and other chemicals that bees placed in an agricultural setting are exposed to.
Topics: Animals; Bees; Disease Susceptibility; Fungicides, Industrial; Nosema; Pesticides; Pollination
PubMed: 23894612
DOI: 10.1371/journal.pone.0070182 -
Nanomaterials (Basel, Switzerland) Jun 2018Trace detection of common pesticide residue is necessary to assure safety of fruit and vegetables, given that the potential health risk to consumers is attributed to the...
Trace detection of common pesticide residue is necessary to assure safety of fruit and vegetables, given that the potential health risk to consumers is attributed to the contamination of the sources. A simple, rapid and effective means of finding the residue is however required for household purposes. In recent years, the technique in association with surface-enhanced Raman scattering (SERS) has been well developed in particular for trace detection of target molecules. Herein, gold nanoparticles (Au NPs) were integrated with sol-gel spin-coated Zirconia nanofibers (ZrO₂ NFs) as a chemically stable substrate and used for SERS application. The morphologies of Au NPs/ZrO₂ NFs were adjusted by the precursor concentrations (_X, X = 0.05⁻0.5 M) and the effect of SERS on Au NPs/ZrO₂ NFs_X was evaluated by different Raman laser wavelengths using rhodamine 6G as the probe molecule at low concentrations. The target pesticides, phosmet (P1), carbaryl (C1), permethrin (P2) and cypermethrin (C2) were thereafter tested and analyzed. Au NPs/ZrO₂ NFs_0.3 exhibited an enhancement factor of 2.1 × 10⁷, which could detect P1, C1, P2 and C2 at the concentrations down to 10, 10, 10 and 10 M, respectively. High selectivity to the organophosphates was also found. As the pesticides were dip-coated on an apple and then measured on the diluted juice containing sliced apple peels, the characteristic peaks of each pesticide could be clearly identified. It is thus promising to use NPs/ZrO₂ NFs_0.3 as a novel SERS-active substrate for trace detection of pesticide residue upon, for example, fruits or vegetables.
PubMed: 29865286
DOI: 10.3390/nano8060402 -
Journal of Insect Science (Online) 2003A series of compounds representing four major pesticide groups were tested for toxicity to beneficial insects representing four different insect orders: Coleoptera...
A series of compounds representing four major pesticide groups were tested for toxicity to beneficial insects representing four different insect orders: Coleoptera (Coccinellidae), Hemiptera (Anthocoridae), Hymenoptera (Aphelinidae), and Neuroptera (Chrysopidae). These materials included organophosphates (methidathion, esfenvalerate and phosmet), carbamates (carbofuran, methomyl and carbaryl), pyrethroids (bifenthrin, fenpropathrin, zeta-cypermethrin, cyfluthrin and permethrin) and the oxadiazine indoxacarb. Toxicity to coccinellid and lacewing species was assessed by treating 1st instar larvae with the recommended field rate of commercial products, and two 10 fold dilutions of these materials, in topical spray applications. Adult Aphytis melinus Debach and 2nd instar Orius insidiosus (Say) were exposed to leaf residues of the same concentrations for 24 h. ANOVA performed on composite survival indices derived from these data resolved significant differences among materials with respect to their overall toxicity to beneficial insects. Cyfluthrin, fenpropathrin and zeta-cypermethrin all increased the developmental time of the lacewing and one or more coccinellid species for larvae that survived topical applications. Bifenthrin increased developmental time for two coccinellid species and decreased it in a third. Indoxacarb (Avaunt WG, DuPont Corp.) ranked highest overall for safety to beneficial insects, largely because of its low dermal toxicity to all species tested. Zeta-cypermethrin (Super Fury), FMC Corporation) received the second best safety rating, largely because of its low toxicity as a leaf residue to A. melinus and O. insidiosus. Phosmet (Imidan 70W, Gowan Co.) and methidathion (Supracide 25W, Gowan Co.) ranked high for safety to coccinellid species, but compounds currently recommended for use in citrus such as fenpropathrin (Danitol 2.4EC, Sumimoto Chem. Co.) and carbaryl (Sevin XLR EC, Rhone Poulenc Ag. Co.) ranked very low for IPM-compatibility based on their relatively high toxicity to all species tested.
Topics: Animals; Carbamates; Citrus; Dose-Response Relationship, Drug; Insecta; Insecticides; Larva; Organophosphates; Oxazines; Pest Control, Biological; Pyrethrins
PubMed: 15841234
DOI: 10.1093/jis/3.1.18 -
Journal of Biomedical Research Sep 2011Pesticides have the potential to leave harmful effects on humans, animals, other living organisms, and the environment. Several human metabolic proteins inhibited after...
Pesticides have the potential to leave harmful effects on humans, animals, other living organisms, and the environment. Several human metabolic proteins inhibited after exposure to organophosphorus pesticides absorbed through the skin, inhalation, eyes and oral mucosa, are most important targets for this interaction study. The crystal structure of five different proteins, PDBIDs: 3LII, 3NXU, 4GTU, 2XJ1 and 1YXA in Homo sapiens (H. sapiens), interact with organophosphorus pesticides at the molecular level. The 3-D structures were found to be of good quality and validated through PROCHECK, ERRAT and ProSA servers. The results show that the binding energy is maximum -45.21 relative units of cytochrome P450 protein with phosmet pesticide. In terms of H-bonding, methyl parathion and parathion with acetylcholinesterase protein, parathion, methylparathion and phosmet with protein kinase C show the highest interaction. We conclude that these organophosphorus pesticides are more toxic and inhibit enzymatic activity by interrupting the metabolic pathways in H. sapiens.
PubMed: 23554709
DOI: 10.1016/S1674-8301(11)60045-6 -
Insects Sep 2021Field-based residual bioassays and residue analysis were conducted to assess the field performance and toxicity longevity of different insecticides that had previously...
Field-based residual bioassays and residue analysis were conducted to assess the field performance and toxicity longevity of different insecticides that had previously been associated with resistance of populations collected from apple and cherry orchards. In this study, 12-24 h-old larvae of apple and cherry populations were exposed to apple and cherry leaf samples, respectively, at post-application intervals and a susceptible population served as a reference of each. In the apple and cherry trials, the order of residual longevity of insecticides that effectively controlled the tested populations was as follows: bifenthrin and spinetoram (apple: 14, cherry 21-day post-application), phosmet (apple: 7, cherry 14-day post-application), chlorantraniliprole (apple: 7-day post-application), and indoxacarb and emamectin benzoate (apple: 1, cherry 7-day post-application). Compared to the susceptible population, the resistant populations resulted in a measurable loss of field performance, or "practical resistance", for the insecticides emamectin benzoate (at 7-day post-application), chlorantraniliprole (at 21-day post-application), and indoxacarb (at all post-application intervals) in the apple trials, while in cherry trial just indoxacarb at 7-day post-application showed a reduced efficacy. In terms of long-lasting residues, only chlorantraniliprole and indoxacarb maintained measurable leaf residues over all post-application intervals while the leaf residues of the other compounds had largely degraded within the first 7 days. These findings can help fruit growers make adjustments to their spray/re-application intervals and optimally utilize important chemical tools in their integrated pest management programs.
PubMed: 34564286
DOI: 10.3390/insects12090846