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Kuttanad is a unique wetland agriculture system featuring polder-based rice cultivation below sea level. Facing increasing pollution threats from agrochemicals, this FAO-recognized Globally Important Agricultural Heritage System (GIAHS) needs constant monitoring and risk assessment. The present study investigated the seasonal dynamics of agricultural pesticide residues in fish cultured in the wetland system. A total of 217 fish samples were analyzed, spanning three different sampling stations of Kuttanad, viz., Vaikom, Ramankari, and Edathua, during pre-monsoon, monsoon, and post-monsoon seasons. The results revealed the presence of 14 pesticides across locations and seasons. The pesticides found in the highest concentrations were propetamphos (54.64 mg L−1), thiacloprid (46.78 mg L−1), and diphenylamine (24.70 mg L−1). The most frequently detected pesticides were propoxur, fenuron, and thiacloprid. Contaminants were detected more frequently during the post-monsoon season (49%) compared to the monsoon (38%) and pre-monsoon (13%) seasons, with imidacloprid being present in all three seasons. The target hazard quotients (THQ) for propetamphos, thiacloprid, and diphenylamine were determined to be 0.04, 0.004, and 0.0002, respectively. The hazard index (HI) calculated as the sum of THQ of quantified pesticides was 0.056, indicating a low to moderate risk. However, consistent monitoring of pesticides in the Kuttanad wetland agriculture system is important to ensure timely intervention to protect biodiversity and human health. [ABSTRACT FROM AUTHOR]

Global male infertility correlated to the rise of endocrine-disrupting chemicals, including insecticides, has grown into a pressing problem. Thiacloprid is one of the most commonly used neonicotinoids that accounts for more than 25% of the global pesticide industry. However, its impact on the reproductive system and male fertility has not been fully elucidated. The object of this study was to explore the adverse effects of thiacloprid on male Wistar rats' reproductive system. Thirty healthy male rats were separated into one of three groups: control group, and two groups that were orally administered with low (22.5 mg/kg) and high dose (62.1 mg/kg) of thiacloprid for 56 days. Thiacloprid significantly (p<0.05) reduced body weight and relative testicular weight, as well as sperm quality (count, motility, viability, and morphology), in a dose-dependent manner. THIA-treated groups revealed a large effect (d > 0.8) on semen quality with Cohen's d of (6.57, 8.82), (20.14, 23.54), and (2.81, 9.10) for count, motility, and viability respectively. Meanwhile, the serum testosterone level dropped while the levels of luteinizing and follicle-stimulating hormones increased. 17ꞵ-hydroxy steroid dehydrogenase and 3ꞵ-hydroxy steroid dehydrogenase levels were significantly decreased in a dose-dependent manner. The activity of the tested antioxidant enzymes catalase (CAT), glutathione reduced (GSH), and superoxide dismutase (SOD) exhibited a considerable decrease compared to the control group with a significant elevation in the lipid peroxidation activity as indicated by malondialdehyde (MDA) level. The testicular histology revealed degenerative changes in spermatogenic cells and interstitial tissue. Comet assay revealed DNA fragmentation in treated groups' testicular tissue. Thiacloprid exposure interferes with reproductive function and impairs male Wistar rat fertility. Such harmful consequences may also develop in humans frequently exposed to thiacloprid. [ABSTRACT FROM AUTHOR]

Background: Neonicotinoids are a group of synthetic insecticides that are highly effective and have a wide range of insecticidal activities. This group includes acetamiprid, dinotefuran, clothianidin, imidacloprid, sulfoxaflor, nitenpyram, thiamethoxam, and thiacloprid. They are extensively used worldwide, both in rural and urban environments. However, the widespread use of neonicotinoids has led to their accumulation and biomagnification in the environment due to their long half-life. This has resulted in the emergence of toxicological and hazardous pollutants, posing significant risks to humans and non-target animals. Neonicotinoids are a type of insecticides that bind to neuronal nicotinic acetylcholine receptors (nAChRs). This mechanism allows them to effectively activate insect nAChRs while having minimal impact on vertebrate nAChRs. This reduces the risk of toxicity and makes them safer for non-target species. However, the presence of neonicotinoids in the environment can still increase the risk of toxicity and exposure. Although they have low affinity for mammalian nAChRs, concerns arise due to the abundance, diversity, and widespread presence of these receptors, as well as their various functions. These factors raise concerns about the potential impact of these pesticides on unintended species. Therefore, it is crucial to remove neonicotinoids from the environment in a sustainable and methodical manner. Various techniques can be employed to eliminate neonicotinoid residues in soil and aquatic habitats. These techniques include physiochemical remediation methods such as advanced oxidation processes, adsorption, oxidation, Fenton technology, photocatalysis, and activated persulfate-based oxidation. Additionally, microbial remediation techniques involving bacteria, fungi, and microalgae can also be utilized. This review aims to focus on the scientific foundation, advancements, and key topics related to microbial remediation technologies for neonicotinoids. Proper implementation of bioremediation techniques can significantly reduce the harmful effects of neonicotinoids on the environment and human health. Short conclusion: The main focus of this review is the new studies on the bioremediation of neonicotinoids by bacteria, fungi, and microalgae, and the role of their enzymes. This topic is gaining importance as pesticide bioremediation techniques become increasingly significant. [ABSTRACT FROM AUTHOR]

The persistence in the environment and possible harmful effects of neonicotinoid insecticides have raised some concerns, which have led to the proposal of various measures for their remediation. The aim of this work was to study the elimination of five neonicotinoids (thiamethoxam (THM), imidacloprid (IMI), clothianidin (CLO), thiacloprid (THC), and acetamiprid (ACE)) using ferrate (Fe(VI)) as the oxidizing agent. Firstly, second-order rate constants for the reactions of neonicotinoids with Fe(VI) were determined at different pHs. The most reactive compound was THC, with a rate constant of 400 ± 43 M−1 s−1 at pH 8 (the optimum pH considering the predominance of the most reactive species (HFeO4−) and the decreasing self-decomposition of Fe(VI) with pH), followed by CLO (10.7 ± 1.7 M−1 s−1), THM (9.7 ± 0.7 M−1 s−1), and IMI (2.5 ± 0.6 M−1 s−1). ACE did not significantly react with Fe(VI). The oxidation of the selected pollutants in secondary effluents by Fe(VI) was rather slow, and only THC could be efficiently removed. The presence of natural organic matter (NOM) exerted a negative influence on the removal of the neonicotinoids of moderate reactivity with Fe(VI) (CLO, THM, and IMI). The additional presence of peroxymonosulfate (Fe(VI)/PMS system) slightly increased the removal of neonicotinoids due to the formation of hydroxyl and sulfate radicals. Finally, the application of the Fe(VI)/sulfite system considerably increased the oxidation rate of the selected pollutants, with enhanced formation of hydroxyl and, especially, sulfate radicals. Overall, these results suggest that the Fe(VI)/sulfite system has significant potential to address environmental and health concerns associated with neonicotinoids in water sources with low NOM content. [ABSTRACT FROM AUTHOR]

Neonicotinoids (NEOs) have been designed to act selectively on insect nicotinic acetylcholine receptors (nAChRs). However, nAChRs are also expressed in vertebrate immune cells, so NEOs may interfere with the immune system in exposed non-target animals. The present study shows that NEOs: imidacloprid and thiacloprid, and their main metabolites: desnitro-imidacloprid and thiacloprid amide, at sub-micromolar concentrations ranging from 2.25 to 20 μM, affect the immune cells of fish. This was found both in primary cultures of leukocytes isolated from the carp head kidney and in the continuous adherent carp monocyte/macrophage cell line. Moreover, the results revealed that the studied pesticides and metabolites generate oxidative stress in carp immune cells and that this is one of the most important mechanisms of neonicotinoid immunotoxicity. Significant increases were observed in the formation of ROS and malondialdehyde (MDA). The antioxidant status alteration was linked with decrease in antioxidant enzyme activity: superoxide dismutase (SOD), catalase (CAT), and non-enzymatic antioxidant glutathione (GSH). Importantly, the metabolites: desnitro-imidacloprid and thiacloprid amide showed significantly higher cytotoxicity towards fish leukocytes than their parent compounds, imidacloprid and thiacloprid, which emphasizes the importance of including intermediate metabolites in toxicology studies. [ABSTRACT FROM AUTHOR]

Indonesia as a megadiverse country and the third largest rice producer in the world utilizes neonicotinoids, a group of systemic insecticides reported to have polluted environmental waters and reduced the abundance of aquatic invertebrates mostly in sub-tropical and temperate countries. To date, no study and regulation on neonicotinoid pollution have been established in Indonesian environmental waters which situates in tropical zone. This research investigated neonicotinoid pollution in seven types of environmental waters of Indramayu Regency (one of the largest rice-producing areas in Indonesia), and assessed the potential risk and toxicity level of detected neonicotinoids to the tropical aquatic environment. Data collections included water sampling and analysis using LC/MS/MS. Results showed that the detection frequency of neonicotinoids was 53% (in 17 out of 32 samples), with imidacloprid and thiamethoxam being the most common compounds detected. The highest total concentration (140.26 ng/L) and the highest concentrations of imidacloprid, thiamethoxam, thiacloprid, dinotefuran, and acetamiprid (48.98 ng/L, 65.14 ng/L, 16.66 ng/L, 23.12 ng/L, and 25.04 ng/L, respectively) were detected in estuaries and mangrove areas. No sample was found to have neonicotinoid concentration above the acute and chronic toxicities of several tropical aquatic organisms assessed. About 19% of the samples contained imidacloprid exceeding the chronic thresholds regulated by The Netherlands, while 6% were also above The United States' regulation, thus encouraging the establishment of necessary actions to prevent unwanted disturbance to the aquatic ecosystem. This study delivered the first report of the occurrence of seven neonicotinoid compounds in seven types of Indonesian environmental waters. [ABSTRACT FROM AUTHOR]

Although pesticides are often discharged into surface waters in pulses as opposed to a sustained release, the effect of episodic pollution events on freshwater crayfish is largely unknown. We monitored change in heart rate and distance moved to assess the response of signal crayfish Pacifastacus leniusculus to short-term exposure to environmentally relevant concentrations of metazachlor (MTZ), terbuthylazine (TER), and thiacloprid (TCL). Crayfish exposed to 20 µg/L of MTZ exhibited a significant increase in mean heart rate and distance moved. Increased heart rate was detected at 118 ± 74 s post-exposure to MTZ. There were no significant differences in mean heart rate and distance moved in crayfish exposed to 6 µg/L of TCL and 4 µg/L of TER. A significant correlation between heart rate and distance moved was found in all exposed groups. These results suggest that pulse exposure to MTZ impact crayfish physiology and behavior during short-term period. With pulse exposure to TCL and TER, crayfish not exhibiting a locomotor response may continue to be exposed to lower, but potentially harmful, levels of pollutants. Evidence of the impacts of pesticide pulse at environmentally relevant concentrations on crayfish is scarce. Further study is required to determine the ecological effects of such events on freshwater crayfish. [ABSTRACT FROM AUTHOR]

Thiacloprid (TH) is a neurotoxic agricultural insecticide and potential food contaminant. The purpose of this study was to investigate the relationship between TH exposure and memory dysfunction in rats, as well as the potential protective effect of piracetam and piracetam-loaded magnetic chitosan nanoparticles (PMC NPs). Rats were divided into five equal groups (six rats/group). The control group received saline. Group II was treated with PMC NPs at a dose level of 200 mg/kg body weight (Bwt); Group III was treated with 1/10 LD50 of TH (65 mg/kg Bwt); Group IV was treated with TH (65 mg/kg Bwt) and piracetam (200 mg/kg Bwt); Group V was co-treated with TH (65 mg/kg Bwt) and PMC NPs (200 mg/kg Bwt). All animal groups were dosed daily for 6 weeks by oral gavage. Footprint analysis, hanging wire test, open field test, and Y-maze test were employed to assess behavioral deficits. Animals were euthanized, and brain tissues were analyzed for oxidative stress biomarkers, proinflammatory cytokines, and gene expression levels of glial fibrillary acidic protein (GFAP), amyloid-beta precursor protein (APP), B-cell lymphoma 2 (Bcl-2), and caspase-3. Brain and sciatic nerve tissues were used for the evaluation of histopathological changes and immunohistochemical expression of tau protein and nuclear factor kappa B (NF-κB), respectively. The results revealed that TH-treated rats suffered from oxidative damage and inflammatory effect on the central and peripheral nerves. The administration of PMC NPs considerably protected against TH-induced neuronal damage, increased antioxidant enzyme activity, decreased inflammatory markers, and improved behavioral performance than the group treated with piracetam. The neuroprotective effect of PMC NPs was mediated through the inhibition of GFAP, APP, caspase-3, Tau, and NF-κB gene expression with induction of Bcl-2 expression. In conclusion, TH could induce oxidative stress, inflammatory and neurobehavior impairment in rats. However, PMC NPs administration markedly mitigated TH-induced brain toxicity, possibly via oxidative and inflammatory modulation rather than using piracetam alone. [ABSTRACT FROM AUTHOR]

Neonicotinoids (NEOs) are a class of insecticides that have high insecticidal activity and are extensively used worldwide. However, increasing evidence suggests their long-term residues in the environment and toxic effects on nontarget organisms. NEO residues are frequently detected in water and consequently have created increasing levels of pollution and pose significant risks to humans. Many studies have focused on NEO concentrations in water; however, few studies have focused on global systematic reviews or meta-analyses of NEO concentrations in water. The purpose of this review is to conduct a meta-analysis on the concentration of NEOs in global waters based on published detections from several countries to extend knowledge on the application of NEOs. In the present study, 43 published papers from 10 countries were indexed for a meta-analysis of the global NEO distribution in water. Most of these studies focus on the intensive agricultural area, such as eastern Asia and North America. The order of mean concentrations is identified as imidacloprid (119.542 ± 15.656 ng L−1) > nitenpyram (88.076 ± 27.144 ng L−1) > thiamethoxam (59.752 ± 9.068 ng L−1) > dinotefuran (31.086 ± 9.275 ng L−1) > imidaclothiz (24.542 ± 2.906 ng L−1) > acetamiprid (23.360 ± 4.015 ng L−1) > thiacloprid (11.493 ± 5.095 ng L−1). Moreover, the relationships between NEO concentrations and some environmental factors are analyzed. NEO concentrations increase with temperature, oxidation–reduction potential, and the percentage of cultivated crops but decrease with stream discharge, pH, dissolved oxygen, and precipitation. NEO concentrations show no significant relations to turbidity and conductivity. [ABSTRACT FROM AUTHOR]

Insecticide applications against the cabbage seedpod weevil, Ceutorhynchus obstrictus Marsham (Coleoptera: Curculionidae), in oilseed rape are conducted during the flowering of the crop. During the flowering period, many parasitoids of pest species are abundant in the crop, and therefore, the preservation of natural pest regulation mechanism is especially important. Parasitism often has a substantial mortality factor in pest populations and as far as possible, parasitoids need to be protected from harmful non-target effects of insecticides. In the present study, the effects of three different insecticidal products on the parasitism of cabbage seedpod weevil larvae were investigated. Additionally, the effects of a spatial targeting of insecticides, using conventional and dropleg application technique, were compared. This was done in field trials within a completely randomized block design and four replications at one trial site in 2019 and two sites in 2020. The parasitoid species Trichomalus perfectus Walker and Mesopolobus morys Walker (both Hymenoptera: Pteromalidae) were abundant in almost equal shares in 2019, whereas M. morys was the most important species in 2020. Only in 2019 were harmful effects of the insecticide Biscaya (a.i. thiacloprid) on parasitism rates of C. obstrictus larvae observed. Clear benefits, due to spatial targeting of insecticides using the dropleg technique on parasitoids, were not found. The harmfulness of insecticides is probably affected by properties of different insecticidal products and the temporal coincidence of parasitoid occurrence and insecticide application. [ABSTRACT FROM AUTHOR]

Pesticide toxicity is typically assessed by exposing model organisms to individual compounds and measuring effects on survival and reproduction. These tests are time-consuming, labor-intensive, and do not accurately capture the effect of pesticide mixtures. Moreover, it is unfeasible to screen the nearly infinite combinations of mixtures for synergistic effects on model organisms. Therefore, reliable molecular indicators of pesticide exposure have to be identified, i.e., biomarkers. These biomarkers can form the basis of rapid and economical screening procedures to assess the toxicity of pesticides even under synergistic interaction with other pollutants. In this study, we screened the expression patterns of eight genes for suitability as a biomarker for neonicotinoid exposure in the soil ecotoxicological model Folsomia candida (springtails). Springtails were exposed to the neonicotinoids imidacloprid and thiacloprid either alone or with various levels of piperonyl butoxide (PBO), which inhibits cytochrome P450 enzymes (CYPs): a common point of synergistic interaction between neonicotinoid and other pesticides. First, we confirmed PBO as a potency enhancer for neonicotinoid toxicity to springtail fecundity, and then used it as a tool to confirm biomarker robustness. We identified two genes that are reliably indicative for neonicotinoid exposure even under metabolic inhibition of CYPs by PBO, nicotinic acetylcholine receptor–subunit alpha 1 (nAchR) and sodium-coupled monocarboxylate transporter (SMCT). These results can form the basis for developing high-throughput screening procedures for neonicotinoid exposure in varying mixture compositions. [ABSTRACT FROM AUTHOR]

The present study assessed the residue levels of six parent neonicotinoids (p-NEOs) and four metabolites (m-NEOs) in indoor dust collected from 12 cities of China. Acetamiprid (ACE) and imidacloprid (IMI) were the predominated p-NEOs (detection rates: 98%) with the median values at 4.54 and 7.48 ng/g dry weight (dw), respectively. N-demethyl-acetamiprid (N-dm-ACE) was the most important m-NEO with the median value at 0.69 ng/g dw, while other m-NEOs were rarely detected (detection rates: < 15%). Significant correlation between ACE and thiacloprid (THD) was observed (p < 0.01), indicating their probably concurrent applications. ACE was significantly correlated to N-dm-ACE (p < 0.01), implicating the degradation of ACE in indoor environment. The estimated daily intake (EDIing) of NEOs via dust ingestion were far lower than the acceptable daily intake for NEOs. To our knowledge, this study provided a baseline nationwide investigation on the occurrence of NEOs in indoor dust of China. [ABSTRACT FROM AUTHOR]

Exposure to numerous chemicals disrupts the spiders' locomotion. Spiders, particularly epigeic spiders, are dependent on their locomotory activities to search for prey, hide from their enemies, and perform sexual reproduction and subsequent parental care. Among the best-known compounds that inhibit the locomotion of arthropods are neonicotinoids. Despite spiders are less affected by the neonicotinoids than insects due to the sequence differences in their acetylcholine receptors, they are not resistant to these compounds. We hypothesized that acute exposure to a broad spectrum of neonicotinoids suppresses the traveled distance, mean velocity, and maximum velocity in epigeic spiders. As a model species, we used adults of Pardosa lugubris. We tested commercial formulations of thiamethoxam, acetamiprid, and thiacloprid. We tested each of the neonicotinoids in the maximum and minimum concentrations recommended for foliar applications. We applied them under controlled conditions dorsally by spraying them directly on the spiders or exposing the spiders to the tarsal contact with neonicotinoid residues. Control groups consisted of 31 individuals; treated groups consisted of 10–21 individuals. We found that a broad spectrum of neonicotinoids temporarily suppresses the traveled distance in epigeic spiders. At 1 h after application, all the three tested neonicotinoid insecticides induced declines in the traveled distance, but this effect mostly disappeared when tested at 24 h after the application. The decrease in the traveled distance was associated with substantial temporary decreases in the mean and maximum velocities. Despite differences among modalities, all three insecticides caused multiple adverse effects on the locomotory parameters in any tested concentrations. It remains to test what would be the lowest safe concentration for the chronic exposure to neonicotinoids in epigeic spiders. [ABSTRACT FROM AUTHOR]

Researchers globally identify pesticides as one of the main reasons for pollinator decline. In the European Union (EU), extensive legislation is implemented to protect pollinators from harmful pesticide exposure. The aim of our study was to discover whether the pesticide residue levels in honeybee matrices, such as nectar and pollen, exceeded the chronic or acute toxicity levels when beehives were located next to fields treated with specific insecticides. The insecticides were used according to the EU legislation and its national implementation. The experiments were conducted in turnip rape, oilseed rape, and caraway fields in southern Finland during the years 2019 and 2020. The pesticides used in the experiments contained the active substances lambda-cyhalothrin (2019), esfenvalerate (2020), and tau-fluvalinate (2020). However, the honeybee-collected pollen and nectar were analyzed for residues of more than 100 active substances. The results showed that the pesticide residue levels clearly remained under the oral acute toxicity for honeybees, although we found high levels of thiacloprid residues in the pollen collected in 2019. The pesticide residues in nectar were below LOQ values, which was most likely due to the rainy weather conditions together with the chosen sampling method. No statistically significant differences were observed between the insecticide-treated and untreated fields. In light of our research, the EU legislation protected honeybees from oral acute toxicity during the years 2019 and 2020. However, potential sublethal effects of thiacloprid and other pesticide compounds found in the collected pollen cannot be ruled out. In the future, constant monitoring of pesticide exposure of honeybees and wild pollinators should be established to ensure that pesticide legislation, and its implementation across the EU successfully protects pollinators and their services in agricultural environments. [ABSTRACT FROM AUTHOR]

The dissipation and residue levels of thiacloprid, spirotetramat and its four metabolites residues in cowpeas were investigated under field conditions. The QuEChERS technique with high-performance liquid chromatography tandem mass spectrometry (HPLC–MS/MS) was used to detect thiacloprid, spirotetramat and its four metabolites residues content in cowpeas. The recoveries were 81.3–95.1% at a spike level of 0.005–0.5 mg/kg, the relative standard deviations (RSDs) were 2.1–9.5%. The dissipation kinetics data showed that thiacloprid and spirotetramat in cowpeas were degraded with the half-lives of 1.14–1.54 days and 1.25–2.79 days. The terminal residues of thiacloprid and spirotetramat were 0.0255–0.4570 mg kg−1 and 0.0314–0.3070 mg kg−1 after application 2 times with a pre-harvest interval (PHI) of 3 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiacloprid in cowpeas for different consumers were 2.44–4.41% and 8.72–15.78%, respectively, and those of spirotetramat were 1.03–1.87% and 0.18–0.32%, respectively, all of the RQ values were lower than 100%. The dietary risk of thiacloprid through cowpeas to consumers was higher than spirotetramat. The results from this study are important reference for Chinese governments to develop criteria for the safe and rational use of thiacloprid and spirotetramat, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. [ABSTRACT FROM AUTHOR]

Pistachio is an economically valuable crop, and Iran is among the biggest producers, exporters, and consumers of this product in the world. During the growing season, pistachios are subjected to multiple sprayings with various pesticides, which result in the accumulation of their residues in nuts. These residues have raised concerns regarding consumers' health. In this research, uptake and dissipation kinetics of insecticides imidacloprid (IMI), thiacloprid (THI), thiamethoxam (THX), and abamectin (ABA) were investigated in pistachio nuts. Field experiments were conducted in a pistachio orchard. Pistachio trees were sprayed with the recommended dose of each insecticide formulation and water as the control. Samplings were performed for up to 49 days. Based on the results, pesticides uptake and dissipation kinetics were best fitted to first-order exponential growth (FOEG) and single first-order kinetic (SFOK) models, respectively. Variations in pesticides uptake/dissipation rates were mostly related to their water solubility, pKa, and log Kow. THX showed a higher uptake rate (0.16 ± 0.04) compared to IMI (0.10 ± 0.01) and THI (0.06 ± 0.01). The fastest dissipation rates were observed for IMI (0.04 ± 0.002 day−1) and THX (0.03 ± 0.001 day−1), while the slowest belonged to THI (0.02 ± 0.003 day−1). ABA residues were below the quantification limit (LOQ) throughout the experiment. Based on FOEG and SFOK model predictions, multiple sprayings with THI and THX resulted in final concentrations exceeding the maximum residue limit (MRL). Hazard quotients for all pesticides were <1, indicating no risk to humans via consumption of the pistachio nut. [ABSTRACT FROM AUTHOR]

Aiming to evaluate the efficacy of constructed floating wetlands (CFW) in removing agrochemicals (nutrients and pesticides), a series of experiments were run continuously for a 16-week period in pilot-scale CFW systems to study the effect of two aquatic plant species (duckweed and water hyacinth) and climatic parameters. The CFW systems were loaded daily with agricultural polluted water containing a fertilizer and five pesticides, whose concentrations and removal efficiencies were measured in the experiments. Average nutrient and pesticide reductions varied from 27.4% to 83.6% and from 12.4% to 42.7%, respectively. The two plants performed almost equally well. High temperatures and increased solar radiation significantly contributed to increased removal performance. The results suggest the use of CFW systems as effective and low-cost agricultural pollution control technologies. [ABSTRACT FROM AUTHOR]

Malnutrition and pesticide exposure are severe factors contributing to the current losses of honeybee colonies. As these stressors often occur combined, we studied the synergistic effects of different diets and pesticide exposure on food choice and mobility of Apis mellifera. We fed beehives with different food sources and exposed the bees to sublethal doses of thiacloprid. After that three different types of honey and pollen were offered in separate choice assays and behaviour towards food was recorded. Thiacloprid significantly affected the food choice in the honey assay, increasing the bees' preference of polyfloral honey, while pre-pesticide diet had no influence. The pollen choice remained similar regardless of treatments, as bees always preferred polyfloral pollen. Interestingly, pesticide exposure affected bee mobility differently, depending on the previous diet. These results indicate that the diet is an important factor influencing the susceptibility to pesticides. [ABSTRACT FROM AUTHOR]

Cyprodinil and thiacloprid are two of the most commonly used pesticides in Turkey. It is more likely to reach humans or animals due to their widespread use. This study aims to investigate whether there is a DNA damage risk due to cyprodinil and thiacloprid exposure. Zebrafish, which is used as a model organism in health and environmental research, and comet assay were chosen to demonstrate this damage. Ten zebrafish per group were exposed to 2 different concentrations for each pesticides (0.31 and 0.155 mg/L for cyprodinil and 1.64 and 0.82 mg/L for thiacloprid) for 21 days. After, gills were excised and comet assay was performed. Photos of an average of 50 cells per slide were taken and were analyzed with visual evaluation program. DNA damage was found to be increased in the 0.31 mg/L cyprodinil, 0.82 mg/L thiacloprid, and 1.64 mg/L thiacloprid treatment groups when compared to the control group (p < 0.001). Average tail DNA percentage parameter values were 9.45 ± 0.51, 10.30 ± 0.34, 11.17 ± 0.33, and 2.47 ± 0.06 respectively. Cyprodinil and thiacloprid were identified as genotoxic agents that should be investigated further. [ABSTRACT FROM AUTHOR]

Samples of leaves, flowers, soil, pollen, bee workers, bee brood, honey, and beeswax were collected to assess the possibility of a transfer of captan, thiacloprid, penthiopyrad, and λ-cyhalothrin from apple trees of Idared variety to honey bee (Apis mellifera) hives. Chemical analyses were performed using the Agilent 7890 Gas Chromatograph equipped with the Micro-cell Electron Capture Detector. It was found that significant amounts of penthiopyrad, the active ingredient of Fontelis 200 SC, were present in leaves, flowers, pollen, bee workers, and beeswax. Simultaneously, captan was present in the brood, worker bees, and honey samples. Significant levels of the captan residues were also detected on the soil surface. In honey samples, captan residue levels exceeded the acceptable standard, reaching 160% of its maximum residue level. However, in no case the amounts of captan, thiacloprid, penthiopyrad, and λ-cyhalothrin ingested with honey by an adult consumer exceeded the level of 0.02% of the acceptable daily intake. Despite the trace amounts of pesticide residues in honey samples collected during the field trial, bee honey consumption can be considered safe. An adult consumer can safely consume about 16 kg of honey. [ABSTRACT FROM AUTHOR]

Whether and to which extent the effects of chemicals in the environment interact with other factors remains a scientific challenge. Here we assess the combined effects of temperature (16 vs. 20°C), light conditions (darkness vs. 400 lx), dissolved organic matter (DOM; 0 vs. 6 mg/L) and the model insecticide thiacloprid (0 vs. 3 µg/L) in a full-factorial experiment on molting and leaf consumption of Gammarus fossarum. Thiacloprid was the only factor significantly affecting gammarids' molting. While DOM had low effects on leaf consumption, temperature, light and thiacloprid significantly affected this response variable. The various interactions among these factors were not significant suggesting additivity. Only the interaction of the factors temperature and thiacloprid suggested a tendency for antagonism. As most stressors interacted additively, their joint effects may be predictable with available models. However, synergistic interactions are difficult to capture while being central for securing ecosystem integrity. [ABSTRACT FROM AUTHOR]

Recent studies have reported interspecific differences in how bee species respond to various stressors. Evaluating the exposure and responses of different bee species to plant protection products is considered an essential part of their risk assessment. This study was conducted to assess the impacts of thiacloprid-prochloraz mixture on buff-tailed bumblebees (Bombus terrestris) and red mason bees (Osmia bicornis) in a worst-case scenario under semi-field conditions. Bumblebee colonies or solitary bee trap nests were confined in tunnels with flowering oilseed rape. The recommended maximum application rates of 72 g thiacloprid/ha and 675 g prochloraz/ha were applied as a tank mixture during bee flight in full flowering oilseed rape. Several parameters such as flight and foraging activity, population parameters, and exposure level were investigated. Our results show adverse effects of the combination of thiacloprid and prochloraz on the reproductive performance of red mason bees. The number of cocoons produced by O. bicornis was significantly reduced in the treatment compared to the control group. Regarding bumblebees, we found no effects of the thiacloprid-prochloraz mixture on any observed parameters of colony development. The maximum detected concentrations of both active substances three days after application were higher in O. bicornis pollen mass compared to B. terrestris stored pollen. We conclude that this worst-case scenario of thiacloprid-prochloraz exposure poses a high risk to solitary bees and thus the use of such mixture should be restricted. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) with cysteamine modified silver-coated gold nanoparticles (Au@Ag-CysNPs) was presented for fast screening of oxamyl and thiacloprid in liquid samples of milk. Concentrations at different levels were detected ranging from 0.5 to 10 ppm by choosing 500–1600 cm−1 spectral range. A strongest Raman peak at 679 cm−1 was ascribed to oxamyl, whereas a band at 1095 cm−1 was associated with thiacloprid in milk samples. The morphology and average size of core-shell nanoparticles (Au@AgNPs) and Au@Ag-CysNPs were acquired by High-resolution transition electron microscopy images and dynamic light scattering. Images showed that Au@AgNPs which had a core size of 28 nm and a shell of 6 nm thickness was modified with 6 nm cysteamine hydrochloride successfully. High coefficient of determination (R2) values of 0.9968 and 0.9875 was calculated for oxamyl and thiacloprid with the limits of detection of 0.031 ppm and 0.023 ppm, respectively. The current novel nanoparticle was easy to prepare and was suitable to serve as a sensitive substrate for SERS detection applications, which could be employed for assessing other accidental contaminants in other food matrices in future studies. [ABSTRACT FROM AUTHOR]

An N2-fixing bacterium, Ensifer meliloti CGMCC 7333, has been reported to degrade the cyano-containing neonicotinoid insecticides acetamiprid and thiacloprid using a nitrile hydratase (NHase). Here, the bioconversion of indole-3-acetonitrile (IAN) by E. meliloti, Escherichia coli overexpressing the NHase, and purified recombinant NHase was studied. E. meliloti converted IAN to the product indole-3-acetamide (IAM), and no nitrilase or amidase activities, or indole-3-acetic acid formation, were detected. Whole cells of E. meliloti converted IAN from the initial content of 6.41 to 0.06 mmol/L in 48 h. Meanwhile, forming 5.99 mmol/L IAM, the molar conversion of 94.4%. E. coli Rosetta overexpressing the NHase from E. meliloti produced 4.46 mmol/L IAM in 5 min, with a conversion rate of 91.1%. The purified NHase had a Vmax for IAN conversion of 294.28 U/mg. Adding 2% and 10% (v/v) dichloromethane to 50 mmol/L sodium phosphate buffer containing 200 mg/L IAN increased the NHase activity by 26.8% and 11.5% respectively, while the addition of 20% hexane had no inhibitory effect on IAN bioconversion. E. meliloti shows high NHase activity without forming a byproduct carboxylic acid, and its tolerance of dichloromethane and hexane increases its potential for application in the green biosynthesis of high-value amide compounds. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are increasingly recognized for their role as information disruptors by modifying the chemical communication system of insects and therefore decreasing the chances of reproduction in target insects. However, data from spiders are lacking. In the present study, we tested the responses of males of a common agrobiont spider, Pardosa agrestis, to the application of field-realistic concentration of acetamiprid, which was formulated as Mospilan, and trace amounts of thiacloprid, which was formulated as Biscaya. We applied fresh or 24-h-old residues of Mospilan or Biscaya to the males just prior to the experiment or treated only the surface of a tunnel containing female draglines. We evaluated the ability of the males to recognize female cues from female dragline silk in a Y-maze. The field-realistic, sublethal doses of Mospilan altered pheromone-guided behavior. The choice of the tunnel with female draglines by males was hampered by tarsal treatment of the males with 24 h-old residues of Mospilan. The mating dance display was commonly initiated in control males that came into contact with female draglines and was suppressed by the Mospilan treatments in all three experimental settings. Some males only initiated the mating dance but did not manage to complete it; this was particularly true for males that were treated tarsally with fresh Mospilan residues, as none of these males managed to complete the mating dance. All three experimental settings with Mospilan decreased the frequency of males that managed to both select the tunnel with female draglines and complete the mating dance. The responses to the low-dose Biscaya were much milder and the study was not sufficiently powered to confirm the effects of Biscaya; however, the surprisingly observed trends in responses to very low Biscaya concentrations call for further analyses of long-term effects of trace amounts of neonicotinoids on the pheromone-guided behavior of spiders. These are the first conclusive data regarding the effects of commercially available formulations of neonicotinoid insecticides on the intraspecific chemical communication of spiders. [ABSTRACT FROM AUTHOR]

The insect repellent IR3535 is one of the important alternative in the fight against mosquito-borne disease such as malaria, dengue, chikungunya, yellow fever and Zika. Using a multidisciplinary approach, we propose the development of an innovative insecticide-based vector control strategy using an unexplored property of IR3535. We have demonstrated that in insect neurosecretory cells, very low concentration of IR3535 induces intracellular calcium rise through cellular mechanisms involving orthosteric/allosteric sites of the M1-muscarinic receptor subtype, G protein βγ subunits, background potassium channel inhibition generating depolarization, which induces voltage-gated calcium channel activation. The resulting internal calcium concentration elevation increases nicotinic receptor sensitivity to the neonicotinoid insecticide thiacloprid. The synergistic interaction between IR3535 and thiacloprid contributes to significantly increase the efficacy of the treatment while reducing concentrations. In this context, IR3535, used as a synergistic agent, seems to promise a new approach in the optimization of the integrated vector management for vector control. [ABSTRACT FROM AUTHOR]

Solitary bees are frequently exposed to pesticides, which are considered as one of the main stress factors that may lead to population declines. A strong immune defence is vital for the fitness of bees. However, the immune system can be weakened by environmental factors that may render bees more vulnerable to parasites and pathogens. Here we demonstrate for the first time that field-realistic concentrations of the commonly used neonicotinoid insecticide thiacloprid can severely affect the immunocompetence of Osmia bicornis. In detail, males exposed to thiacloprid solutions of 200 and 555 µg/kg showed a reduction in hemocyte density. Moreover, functional aspects of the immune defence - the antimicrobial activity of the hemolymph - were impaired in males. In females, however, only a concentration of 555 µg/kg elicited similar immunosuppressive effects. Although males are smaller than females, they consumed more food solution. This leads to a 2.77 times higher exposure in males, probably explaining the different concentration thresholds observed between the sexes. In contrast to honeybees, dietary exposure to thiacloprid did not affect melanisation or wound healing in O. bicornis. Our results demonstrate that neonicotinoid insecticides can negatively affect the immunocompetence of O. bicornis, possibly leading to an impaired disease resistance capacity. [ABSTRACT FROM AUTHOR]

A rapid and sensitive immunoassay for the simultaneous detection of imidacloprid and thiacloprid was developed by using magnetic nanoparticles (MNPs) and upconversion nanoparticles (UCNPs). The UCNPs of NaYF4:Yb, Er and NaYF4:Yb, Tm were synthesized and conjugated with anti-imidacloprid monoclonal antibody (mAb) and anti-thiacloprid mAb as signal labels, while the MNPs were conjugated with antigens of thiacloprid and imidacloprid as separation elements. The fluorescence intensities of Yb/Er- and Yb/Tm-doped UCNPs were detected simultaneously in 544 nm and 477 nm under the excitation of NIR light (980 nm). The amounts of mAb-conjugated UCNPs that were separated by antigen-conjugated MNPs were determined based on competitive immunoassays. Under the optimal conditions, the 50% inhibiting concentration (IC50) and limit of detection (LOD, IC10) were 5.80 and 0.32 ng/mL for imidacloprid and 6.45 and 0.61 ng/mL for thiacloprid, respectively. The immunoassay exhibited negligible cross-reactivity with analogs of imidacloprid and thiacloprid except imidaclothiz (86.2%). The average recoveries of imidacloprid and thiacloprid in environmental and agricultural samples, including paddy water, soil, pears, oranges, cucumbers, and wheat, ranged from 78.4 to 105.9% with relative standard deviations (RSDs) of 2.1–11.9% for imidacloprid and ranged from 82.5 to 102.3% with RSDs of 1.0–16.5% for thiacloprid. In addition, the results of the immunoassay correlated well with high-performance liquid chromatography for the detection of the authentic samples. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to evaluate the presence of five neonicotinoid pesticides, acetamiprid, imidacloprid, clothianidin, thiacloprid, and thiamethoxam, in sheep and cow milk samples collected from animals bred in the Jordan Valley. In this area, numerous citrus plantations are present, and these insecticides are commonly used to protect plants from pests and diseases. Thirty-seven sheep milk samples and 31 cow milk samples were analysed. The analytical method, based on a single cleanup extraction step with SPE cartridges packed with diatomaceous earth material, together with analysis by LC-MS/MS, has guaranteed average recoveries between 75.1% and 88.3%, limits of detection (LOD) and quantification (LOQ) of 0.5 and 1 µg/kg, respectively, for all the five neonicotinoids. LOQ was much lower than the codex maximum residues limits for these pesticides in milks. No residues of the five neonicotinoids were found in any sample at a concentration level above LOD. [ABSTRACT FROM AUTHOR]

Larval parasitoids can substantially reduce the population density of the pollen beetle [Brassicogethes aeneus (Fabricius), syn. Meligethes aeneus (Fabricius)]. The most abundant tersilochine parasitoids of pollen beetle are Tersilochus heterocerus, Phradis interstitialis and P. morionellus. The main activity of these parasitoids was observed in the period shortly before flowering to full flowering of oilseed rape. Insecticide applications during this period may have negative effects on parasitoids. In the present study, the effects of the insecticides Biscaya (a.i. thiacloprid), Mavrik (a.i. tau-fluvalinate) and Karate Zeon (a.i. lambda-cyhalothrin) applied during the bud or flowering stage of winter oilseed rape on parasitization of pollen beetle larvae by T. heterocerus were studied in 12 field trials at different locations in Germany in 2013-2015. The effects on parasitism by Phradis spp. were assessed in 2015. Parasitism of pollen beetle larvae by T. heterocerus was found in all field trials in all experimental years, but in most trials not before full flowering. Maximum percentage of parasitized larvae at different locations ranged between 3.4 and 16.8% in 2013, 8.3 and 22.4% in 2014 and from 11.1 to 29.1% in 2015. Levels of parasitism were not significantly different between the untreated control and insecticide treatments within each location. In contrast to T. heterocerus, Phradis spp. was not detected at all locations and not before flowering declining. In field trials at Lucklum and Puch, the maximum level of parasitism by Phradis spp. was 9.4 and 18.3%, respectively. No significant effect of insecticide application on parasitism by Phradis spp. was observed between the treatments. The results of this study showed that the insecticides used in the field trials did not affect parasitization of pollen beetle larvae by T. heterocerus and Phradis spp., regardless whether applied at the bud stage, at the beginning of flowering or full flowering. [ABSTRACT FROM AUTHOR]

One of the main insect pests in oilseed rape is the pollen beetle (Brassicogethes aeneus (Fabricius), syn. Meligethes aeneus). To maximize efficiency of control of this pest, insecticides are required that ideally, not just prevent yield losses by bud feeding of overwintered pollen beetles, but simultaneously minimize the reproduction of the pest, thereby reducing the size of the following generation infesting next year’s oilseed rape. The neonicotinoid active substance thiacloprid is known to reduce bud infestation with eggs and larvae. However, the mechanisms by which this occurs as well as the effects of other active substances are not known. In this study, the effects of the neonicotinoid insecticide Biscaya (a.i. thiacloprid) and the pyrethroids Mavrik (tau-fluvalinate) and Karate Zeon (lambda-cyhalothrin) applied at the bud stage of winter oilseed rape with recommended field rates on infestation of buds with eggs and larvae of pollen beetles were tested in field trials in Germany in 2013-2015. In additional greenhouse experiments, it was investigated whether effects on bud infestation were caused by lethal effects on pollen beetle or by insecticidal residues on plants causing sublethal effects. In the field trials, application of Biscaya and Mavrik significantly reduced the percentage of buds containing eggs and larvae in contrast to Karate Zeon. In 2014 and 2015, 14 days after application, bud infestation on the main raceme was reduced by 86 and 82%, respectively, in Biscaya-treated plots and by 51 and 71%, respectively, in Mavrik-treated plots compared to the untreated plots. In the greenhouse experiments, the lowest percentage of bud infestation with eggs and larvae was recorded on Biscaya-treated plants whereas on Mavrik-treated plants, there was no significant difference compared with the control. The results of the field trials show that Biscaya and Mavrik reduced oilseed rape bud infestation with eggs and larvae of pollen beetles primarily by lethal effects on overwintered pollen beetles or by repellency. However, Biscaya had additional effects on egg laying, which was supported by the greenhouse experiments. [ABSTRACT FROM AUTHOR]

Field and lab trials took place in Crete (July to September 2016), concerning the residual degradation and toxicity of seven active ingredients applied as bait sprays against the olive fruit fly. Highest residues were recorded in olive leaves for dimethoate and phosmet (~ 60 mg/kg) immediately after application (day 1+), while a threefold and fivefold reduction was observed 1 week later, respectively. Residues of pyrethroids were determined at lower levels (< 10 mg/kg) but remained almost stable for a longer period of time. Finally, thiacloprid and spinosad residues were determined at 5.81 and 0.19 mg/kg respectively (day 1+), and rapidly decreased below the LOQ. Highest toxicity against the olive fruit fly was observed just right after the application of dimethoate (100%), a-cypermethrin (80%), and l-cyhalothrin (72.92%). Although the toxicity of dimethoate was significantly reduced 1 week after the application (80%) and then minimized, toxicity of pyrethroids remained almost stable (> 60%) for the first 2 weeks and then decreased to 30-40%, which remained stable up to the end of the study (8 weeks). Concerning phosmet, its toxicity ranged from 35 to 56% for 3 weeks with no significant reduction, while spinosad presented a lower toxicity profile (50% only for 1 week). The benefits of these results in the knowledge of insecticide residues and their toxicity against olive fruit fly can be used for improving olive fruit fly control. [ABSTRACT FROM AUTHOR]

Winter oilseed rape is an important crop in agriculture, where it plays an essential role in cereal-based crop rotations. The main pest in this crop is the pollen beetle which feeds on developing buds. Since 1999, pyrethroid resistance in the pollen beetle has spread throughout Europe. Denmark and Sweden are of interest due to the early detection of pyrethroid-resistant pollen beetle and because of the presence of both target-site and metabolic resistance in the populations. For almost ten years, neonicotinoid insecticides have been used in oilseed rape as well. In this study, the current resistance situation in Danish pollen beetle populations was conducted. The susceptibility of pollen beetle to the synthetic pyrethroid λ-cyhalothrin as well as the neonicotinoid thiacloprid was investigated. Sixty-eight Danish, as well as 6 Swedish and 10 German populations collected between 2014 and 2016 were tested with λ-cyhalothrin. Two-thirds of the Danish populations collected were classified as pyrethroid resistant, whereas Swedish populations were mostly susceptible and all German populations tested were resistant, mostly at higher levels than those detected in Danish strains. Toxicological parameters were calculated by a two-parameter log-logistic model and showed up to 58-fold variation at LC for λ-cyhalothrin and up to 17-fold variation at LC for thiacloprid. However, almost all Danish populations were susceptible against thiacloprid and the German populations showed up to sevenfold variation in thiacloprid bioassay. In conclusion, pyrethroid resistance is widespread in Danish pollen beetle populations with regional differences, whereas Danish populations are susceptible to thiacloprid in all regions. [ABSTRACT FROM AUTHOR]

In moths, sexual behavior combines female sex pheromone production and calling behavior. The normal functioning of these periodic events requires an intact nervous system. Neurotoxic insecticide residues in the agroecosystem could impact the normal functioning of pheromone communication through alteration of the nervous system. In this study we assess whether sublethal concentrations of the neonicotinoid insecticide thiacloprid, that competitively modulates nicotinic acetylcholine receptors at the dendrite, affect pheromone production and calling behavior in adults of three economically important tortricid moth pests; Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). Thiacloprid significantly reduced the amount of calling in C. pomonella females at LC (a lethal concentration that kills only 1 in 10 individuals), and altered its calling period at LC, and in both cases the effect was dose-dependent. In the other two species the effect was similar but started at higher LCs, and the effect was relatively small in L. botrana. Pheromone production was altered only in C. pomonella, with a reduction of the major compound, codlemone, and one minor component, starting at LC. Since sex pheromones and neonicotinoids are used together in the management of these three species, our results could have implications regarding the interaction between these two pest control methods. [ABSTRACT FROM AUTHOR]

This study investigated the neurological effects of residual ground-water levels of thiacloprid on the non-target organism Caenorhabditis elegans. Nematodes treated with thiacloprid showed a dose-dependent and significantly increased twitch response at concentrations above 50 ng mL that disabled their forward locomotion in liquid culture. In comparison with untreated controls, 10 ng mL thiacloprid perturbed the chemosensory ability of C. elegans such that the nematodes no longer demonstrated positive chemotaxis towards a NaCl chemo-attractant, reducing their chemotaxis index from +0.48 to near to zero. Nematodes also exhibited a locomotion characteristic of those devoid of chemo-attraction, making significantly more pirouetting turns of ≥90° than the untreated controls. Compared to the untreated controls, expression of the endocytosis-associated gene, Rab-10, was also increased in C. elegans that had developed to adulthood in the presence of 10 ng mL thiacloprid, suggesting their active engagement in increased recycling of affected cellular components, such as their nAChRs. Thus, even residual, low levels of this less potent neonicotinoid that may be found in field ground-water had measurable effects on a beneficial soil organism which may have environmental and ecological implications that are currently poorly understood. [ABSTRACT FROM AUTHOR]

Purpose: In mine soils, especially from arid or semiarid areas, the use of low-quality water for irrigation is a usual practice. Therefore to fill this gap, different experiments have been carried out to evaluate the effect of compost, pesticide and wastewater on the growth of tomato plants in a mine soil located at an iron extraction area. Materials and methods: Soils proceeded from Alquife mine wastes whose most outstanding characteristics are alkaline conditions, low organic matter and electrical conductivity and high As concentration. The compost of sewage sludge (CSL) used to amend this soil had a slightly acid pH (6.8), EC 3.0 ± 0.07 dS m (1/10 ratio, m/V) and 10 % organic carbon (OC) content. Irrigation was performed with distilled water (DW) or wastewater (WW) and two pesticides, the insecticide thiacloprid and the fungicide fenarimol, were applied to the soil. Tomato was grown directly from seeds on each pot. Four treatments with addition of pesticides were considered. For comparison purposes, two additional treatments without pesticides were also included. Results and discussion: Addition of compost of sewage sludge led to a significant and sustained increase of soil OC content and dehydrogenase activity, while irrigation with wastewater had a slight or negligible effect on both properties. The plant species responded negatively to wastewater irrigation when this practice was undertaken with the application of both pesticides. No detectable amounts of thiacloprid, a relatively unstable and polar insecticide, were found in soil. The concentration of fenarimol in soil was higher after amendment with compost, but was not modified by irrigation with wastewater. In tomato shoots, the amounts of both pesticides were inversely correlated with final soil organic carbon, indicating that this soil property is relevant for their plant uptake. Besides, fenarimol concentrations in the soil and the tomato shoots were inversely related ( r = −0.836). Conclusions: Tomato was not able to grow healthy in Alquife mine soil without compost addition. The irrigation with wastewater only reduced plant growth when used in combination with pesticides. Uptake of both pesticides by tomato plants was negligible according to the low bioaccumulation factor values, but was almost doubled for wastewater irrigation. Caution should be taken with the use of treated wastewater, because it may reduce plant growth in tomato that is a species sensitive to salinity. [ABSTRACT FROM AUTHOR]

In a recent study, we showed that the springtail Folsomia candida was quite sensitive the neonicotinoid insecticides imidacloprid and thiacloprid. This study aimed at determining the toxicity of both compounds to F. candida following exposure over three generations, in natural LUFA 2.2 standard soil. In the first generation, imidacloprid was more toxic than thiacloprid, with LCs of 0.44 and 9.0 mg/kg dry soil, respectively and ECs of 0.29 and 1.5 mg/kg dry soil, respectively. The higher LC/EC ratio suggests that thiacloprid has more effects on reproduction, while imidacloprid shows lethal toxicity to the springtails. In the multigeneration tests, using soil spiked at the start of the first generation exposures, imidacloprid had a consistent effect on survival and reproduction in all three generations, with LCs and ECs of 0.21-0.44 and 0.12-0.29 mg/kg dry soil, respectively, while thiacloprid-exposed animals showed clear recovery in the second and third generations (LC and EC > 3.33 mg/kg dry soil). The latter finding is in agreement with the persistence of imidacloprid and the fast degradation of thiacloprid in the test soil. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the hematological, biochemical, and histopathological changes due to thiacloprid toxicity, and the potential protective role of flaxseed oil in male Wistar albino rats. Subacute thiacloprid intoxication induced a significant increase in RBCs, Hb, PCV, and WBCs count, and bone marrow micronucleus (MN) formation. Moreover, there was a significant increase in serum biochemical parameters related to hepatic injury: alanine aminotransferase (ALT) and alkaline phosphatase (ALP). Serum total protein and albumin levels were significantly reduced. Thiacloprid increases tumor necrosis factor-alpha (TNF-α) and interleukine-2(IL-2). There was a significant decrease in glutathione-S-transferase, while the lipid peroxidation (MDA) and cytochrome P450 activity were significantly increased. Flaxseed oil coadministration partially retrieved the changes in all studied parameters. Thiacloprid induced histopathological liver damage, which was minimized as a result of flaxseed oil treatment. In general, it was concluded that, flaxseed oil able to protect against thiacloprid-induced hepatoxicity. [ABSTRACT FROM AUTHOR]

Lysiphlebus fabarum Marshall is the main parasitoid of the black bean aphid, Aphis fabae Scopoli. Lethal and sublethal effects of insecticides, thiacloprid+deltamethrin, pirimicarb and pymetrozine were evaluated on the parasitoid under laboratory conditions. One-day-old mummies were exposed to the recommended field concentration of either insecticides via dipping method. Adult emergences were reduced by 82.67, 19.98 and 10.67 % for thiacloprid+deltamethrin, pirimicarb and pymetrozine treatments, respectively. Thiacloprid+deltamethrin had the most adverse effect on the fecundity of the emerged females, while pirimicarb and pymetrozine did not have such effects. According to International organization for biological control (IOBC) insecticide toxicity classification, thiacloprid+deltamethrin resulted to be moderately harmful (E = 97.39%), whereas pirimicarb (E = 15.78%) and pymetrozine (E = 5.15%) were harmless. Thiacloprid+deltamethrin negatively affected five of the estimated demographic parameters ( GRR, R , r, λ and T ). Pirimicarb negatively affected GRR, R and T, while it had no adverse effects on r and λ. None of the studied demographic parameters were affected by pymetrozine. Our results suggest that pirimicarb and pymetrozine can be considered as safe for L. fabarum, but that thiacloprid+deltamethrin can have serious detrimental of this parasitoid in the field. [ABSTRACT FROM AUTHOR]

The binding of thiaclopride (THI), a neonicotinoid insecticide, with Aplysia californica acetylcholine binding protein ( Ac-AChBP), the surrogate of the extracellular domain of insects nicotinic acetylcholine receptors, has been studied with a QM/QM′ hybrid methodology using the ONIOM approach (M06-2X/6-311G(d):PM6). The contributions of Ac-AChBP key residues for THI binding are accurately quantified from a structural and energetic point of view. The importance of water mediated hydrogen-bond (H-bond) interactions involving two water molecules and Tyr55 and Ser189 residues in the vicinity of the THI nitrile group, is specially highlighted. A larger stabilization energy is obtained with the THI- Ac-AChBP complex compared to imidacloprid (IMI), the forerunner of neonicotinoid insecticides. Pairwise interaction energy calculations rationalize this result with, in particular, a significantly more important contribution of the pivotal aromatic residues Trp147 and Tyr188 with THI through CH···π/CH···O and π-π stacking interactions, respectively. These trends are confirmed through a complementary non-covalent interaction (NCI) analysis of selected THI- Ac-AChBP amino acid pairs. [ABSTRACT FROM AUTHOR]

The aim of this work is the development of a simple, fast, quantitative, and economic method for the determination of neonicotinoid insecticide residues in dietary bee pollen. Several parameters of the method, such as extraction solvent, extraction time, and solid-phase extraction sorbents for purification [silica, C, primary-secondary amine (PSA), and Envi-Carb II/PSA], were studied. The final proposed method based on solid-liquid extraction with hexane, cleanup with Supelclean™ Envi-Carb II/PSA cartridges, and subsequent analysis by high-performance liquid chromatography with tandem mass spectrometry was validated and applied to the analysis of commercial bee pollen samples from different geographical zones. Method performance was assessed by the evaluation of several quality parameters of the method, such as recovery values, repeatability, reproducibility, linearity, and limits of detection and quantification. Matrix effects on the chromatographic signal were also studied. The quality parameters of the method were equivalent to or better than those obtained with previously published methods, with recoveries between 81 and 99 % and repeatabilities lower than 8.8 %. The detection and quantification limits were in the ranges 0.2-2.2 μg kg and 0.4-4.3 μg kg, respectively. [ABSTRACT FROM AUTHOR]

Two-spotted spider mite is a major pest of many agricultural and ornamental crops worldwide. Some reports have indicated that application of neonicotinoid insecticides may lead to increased fecundity of this pest. If this is found to be true, the use of these pesticides may cause an outbreak of spider mite populations. Sublethal effects of three neonicotinoids, namely thiacloprid, acetamiprid and thiamethoxam were studied on T. urticae adults at field recommended doses. The experiments were carried out using bean leaf pieces in plastic Petri dishes. The adult mites were treated using two methods: (1) drench application and (2) spraying of leaves with Potter Spray Tower. Our results indicated that all neonicotinoids tested increased T. urticae population. In both treatment methods, acetamiprid treated mites had the highest intrinsic rate of population increase (r) and finite rate of population increase ( λ); and the lowest mean generation time ( T) and doubling time among the treatments. If similar results are obtained from greenhouse and field trials, the use of these insecticides requires necessary precautions such as avoiding repeated use of neonicotinoid insecticide for controlling insect pests. [ABSTRACT FROM AUTHOR]

Thiacloprid, a neonicotinoid insecticide, has been used widely in agriculture worldwide. In recent years, the adverse effects of neonicotinoid insecticides on non-target organisms have attracted more and more attention. In the present study, effects of thiacloprid on molecular biomarkers (GST, CarE, CAT, SOD, POD, and DNA damage) of earthworm Eisenia fetida were investigated using the artificial OECD soil for the first time. Earthworms were exposed to thiacloprid (1 and 3 mg/kg) for 7, 14, and 28 days and then transferred to the clean OECD soil for 35, 42, and 56 days. Results showed that activities of GST, CarE, CAT, SOD, and POD are inhibited following the exposure to thiacloprid at one or more sample times and then increased during the recovery course compared with the control. Significant DNA damage to E. fetida was also observed by olive tail moments in comet assay. These results suggested that thiacloprid could have harmful effect on earthworms, and these studied biomarkers might be used in the assessment of the risk of thiacloprid to the soil ecosystem environment. [ABSTRACT FROM AUTHOR]

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Irrigation of agricultural soils with low-quality waters, a common practice in arid and semiarid regions, may affect the fate of organic pollutants increasing the risk of groundwater contamination. Desorption of thiacloprid (THC) and fenarimol (FEN) preadsorbed on two calcareous soils (SV, RM3) has been investigated using different solutions: MilliQ water (control), urban treated wastewater (WW), anionic (A22, BP) and non-ionic (TW-80, TX-100) surfactants, dissolved organic matter from sewage sludge (SS-Ph, SS-MQ), and inorganic salt solutions (CaCl, (NH)SO). WW did not affect in general pesticide desorption. Desorption of THC was significantly enhanced with BP (up to 35.4 % in SV) at concentrations higher that those normally found in WW, while that of FEN was reduced at high concentrations of A22, a fact attributed to precipitation of the surfactant salt with Ca from soils. The non-ionic surfactant TW-80 at levels with environmental relevance (ca. 4-80 mg l) drastically enhanced FEN solubilization from soils (an increase between 52 % and 90 %). Inorganic salts in solution in the concentration range studied (5-10 mM) only influenced FEN desorption, but the effect was variable depending on the salt and on the soil. Finally, FEN desorption from RM3 increased linearly with increasing concentrations of SS-MQ ( R = 0.994), whereas it decreased as the SS-Ph concentration increased in solution ( R = 0.846). It can be concluded that pesticide desorption is mainly controlled by the composition of the irrigation solution, with a higher effect especially on the more hydrophobic compound. [ABSTRACT FROM AUTHOR]

Thiacloprid, a neonicotinoid insecticide with novel mode of action, is found to be effective against several lepidopteran as well as hemipteran pests. The present studies were carried out to observe the persistence pattern of thiacloprid on brinjal and to suggest suitable waiting period for the safety of consumers. Persistence of thiacloprid in brinjal was studied following three applications of thiacloprid (Alanto 240 SC) at 180 and 360 g a.i. ha at 7 days interval. Residues of thiacloprid in brinjal were estimated by high-performance liquid chromatography and were confirmed by liquid chromatography-mass spectrometry. The average initial deposits of thiacloprid were observed to be 0.48 and 1.05 mg kg on the brinjal fruit following third application of thiacloprid at recommended and double the recommended dosages, respectively. Half-life periods for thiacloprid were found to be 0.47 and 0.50 days at single and double the application rates, respectively. Residues of thiacloprid declined below its limit of quantification of 0.05 mg kg after 3 and 5 days, respectively, at recommended and double the recommended application rates. Therefore, the use of thiacloprid does not seem to pose any risk hazard and a waiting period of 1 day is suggested for safe consumption of brinjal fruits. [ABSTRACT FROM AUTHOR]

Flubendiamide, a phthalic acid diamide protects the plants against a broad range of economically important lepidopterus pests and thiacloprid a second generation neonicotinoid is effective against the sucking insects, white flies and jassids. To estimate the residues of flubendiamide and thiacloprid on tomato, analytical methods were validated by conducting recovery studies, residues were quantified by using HPLC on C column and PDA at 260 λ. Residues of flubendiamide declined below detectable level of 0.01 mg kg after 5 and 7 days of application at lower and higher dose with RL of 0.72 and 1.32 days, respectively. Thiacloprid residues reached below its detectable level of 0.01 mg kg after 5 and 7 days of its lower and higher dose with RL of 0.83 and 1.79 days, respectively. [ABSTRACT FROM AUTHOR]

Thiacloprid is a systemic neonicotinoid. The study hypothesized that difference may be seen in the rate of dissipation of thiacloprid when applied on non-transgenic and transgenic cabbage. Thiacloprid was estimated by HPLC. Half life of thiacloprid in transgenic as well as in normal cabbage ranged between 12.3-13.1 days in two doses of application. Under field condition, after 15 days, 59.2 % and 54.3 % dissipation was recorded at lower and higher rates of application in transgenic cabbage, where as the insecticide dissipated 57.5 % and 59.1 % for single dose and double dose application, respectively in non-transgenic cabbage. The study establishes that there is no significant difference in dissipation of a systemic pesticide in transgenic versus non-transgenic cabbage. Decontamination of thiacloprid contaminated cabbage was carried out by different chemical treatments. The application of 0.5 % NaHCO (an edible alkali) may be recommended for decontamination. Thiacloprid residues in the day-3 field samples of cabbage could be reduced below Japanese MRL (1.0 mg kg) by treating with 0.5 % NaHCO solution for 1 h. [ABSTRACT FROM AUTHOR]

In order to examine the persistence behavior, safety evaluation and utilization of residue data for fixation of thiacloprid MRL, a supervised field trial in tea was conducted at Darjeeling. The HPLC analysis of thiacloprid in green tea leaves indicates that the initial deposits of 2.14 and 3.95 mg kg, which declined gradually and persisted until day 14 to the tune of 0.23 and 0.45 mg kg respectively. The residues in processed tea samples prepared from green tea leaves of 7 and 14th day were 3.0-3.8 times less. Thiacloprid did not infuse to tea liquor from processed tea. The half-life value in green tea leaves ranged from 4.29 to 4.31 days. Considering the EU MRL value of 10 mg kg and risk assessment calculation, thiacloprid at 30 g a.i. ha appears to be safe in plant protection schedules and first round of plucking of green tea leaves on day 7 is recommended. [ABSTRACT FROM AUTHOR]