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Termiticides are widely used to protect wooden houses from termites. Dieldrin, chlordane, heptachlor, and chlorpyrifos, which are effective termiticides, have been banned because of their high toxicity. Neonicotinoids, pyrethroids, phenyl pyrazoles, and triazoles have been used as alternatives to termiticides in indoor environments. However, despite numerous studies showing that farm-applied pesticides contaminate house dust, the health risks to humans from indoor termiticides remain unclear. We collected house dust and indoor air samples from 37 and 7 houses, respectively, to investigate the indoor termiticide contamination levels. The minimum margin of exposure to fipronil was 173, indicating that fipronil posed the highest risk among the targeted 28 compounds in indoor environment. The mean concentrations of alternative termiticides in house dust and air samples ranged from 1,126 ng g(- 1) (cyproconazole) to 5,356 ng g(- 1) (MGK-264) in thirty-seven houses and 0.08 ng m(- 3) (acetamiprid) to 34 ng m(- 3) (MGK-264) in seven houses, respectively. These results are comparable to the pesticide concentrations in houses close to farms where pesticides were applied, and are higher than atmospheric pesticide concentrations in oceans. Therefore, houses sprayed with termiticides may be as contaminated as agricultural environments where farmers apply substantial quantities of pesticides. The main route of exposure was air inhalation for fipronil, and both air inhalation and house dust ingestion for triazoles and potentiators. Establishment of regulations and development of decontamination methods are needed for indoor contamination of termiticides. Floor cleaning may be effective to remove termiticides that are ingested mainly through the house dust pathway.

期刊论文 2025-06-18 DOI: 10.1007/s11869-025-01767-8 ISSN: 1873-9318

Pesticides including insecticides are often applied to prevent distortion posed by plant insect pests. However, the application of these chemicals detrimentally affected the non-target organisms including soil biota. Fipronil (FIP), a broad-spectrum insecticide, is extensively used to control pests across the globe. The frequent usage calls for attention regarding risk assessment of undesirable effects on non-target microorganisms. Here, laboratory-based experiments were conducted to assess the effect of FIP on plant-beneficial bacteria (PBB); Rhizobium leguminosarum (Acc. No. PQ578652), Azotobacter salinestris (Acc. No. PQ578649) and Serratia marcescens (Acc. No. PQ578651). PBB synthesized growth regulating substances were negatively affected by increasing fipronil concentrations. For instance, at 100 mu g FIPmL-1, a decrease in indole-3-acetic acid (IAA) synthesis by bacterial strains followed the order: A. salinestris (95.6%) S. marcescens (91.6%) > R. leguminosarum (87%). Also, exposure of bacteria cells to FIP hindered the growth and morphology of PBB observed as distortion, cracking, and aberrant structure under scanning electron microscopy (SEM). Moreover, FIP-treated and propidium iodide (PI)-stained bacterial cells displayed an insecticide dose-dependent increase in cellular permeability as observed under a confocal laser microscope (CLSM). Colony counts (log(10) CFU mL(-1)) and growth of A. salinestris was completely inhibited at 150 mu g FIPmL-1. The surface adhering ability (biofilm formation) of PBB was also disrupted/inhibited in a FIP dose-related manner. The respiration loss due to FIP was coupled with a reduction in population size. Fipronil at 150 mu gmL(-1) decreased cellular respiration in A. salinestris (72%) S. marcescens (53%) and R. leguminosarum (85%). Additionally, biomarker enzymes; lactate dehydrogenase (LDH), lipid peroxidation (LPO), and oxidative stress (catalase; CAT) induced by FIP represented significant (p <= 0.05) toxicity towards PBB strains. Conclusively, fipronil suggests a toxic effect that emphasizes their careful monitoring in soils before application and their optimum addition in the soil-plant system. It is high time to prepare both target-specific and slow-released agrochemical formulation for crop protection with concurrent safeguarding of soils.

期刊论文 2024-12-01 DOI: 10.1007/s11274-024-04203-8 ISSN: 0959-3993

Pesticides including insecticides are applied in agricultural practices to control insect pests. However, their excessive usage often poses a severe threat to the growth, physiology, and biochemistry of plants. Here, responses of chickpea and greengram seedlings exposed to three fipronil (FIP) concentrations i. e. 100 (1x), 200 (2x) and 300 (3x) mu g mL- 1 was evaluated under in vitro. Among doses, 3x had a greater negative impact on germination attributes, root-shoot elongation, vigor indices, length ratios, and survival of seedlings. Besides, the morphological distortion in root tips, oxidative stress generation, and cellular death in fipronil-supplemented root seedlings were observed under scanning electron (SEM) and confocal laser scanning (CLSM), respectively. A significant (p <= 0.05) and pronounced upsurge in plant stressor metabolites such as proline, malondialdehyde (MDA), electrolyte leakage (EL), hydrogen peroxide (H2O2) content, and antioxidants enzymes in plant seedlings further confirmed the fipronil toxicity. In addition, a concentration-dependent decrease in respiration efficiency (RE) and ATP content in FIP-treated seedlings was observed. Reduced mitotic index (MI) and numerous chromosomal anomalies (CAs) in root meristematic cells of seedlings are a clear indication of insecticide-induced cytotoxicity. Furthermore, a dose-dependent increase in DNA damage in root meristematic cells of greengram revealed the genotoxic potential of fipronil. Conclusively, fipronil suggested phyto and cyto-genotoxic effects that emphasize their careful monitoring in soils before application and their optimum addition in soil-plant systems. It is high time to prepare both target-specific and slow-released agrochemical formulations for crop protection with concurrent safeguarding of the soil.

期刊论文 2024-11-01 DOI: 10.1016/j.pestbp.2024.106135 ISSN: 0048-3575

Conventional soil management in agricultural areas may expose non-target organisms living nearby to several types of contaminants. In this study, the effects of soil management in extensive pasture (EP), intensive pasture (IP), and sugarcane crops (C) were evaluated in a realistic-field-scale study. Thirteen aquatic mesocosms embedded in EP, IP, and C treatments were monitored over 392 days. The recommended management for each of the areas was simulated, such as tillage, fertilizer, pesticides (i.e. 2,4-D, fipronil) and vinasse application, and cattle pasture. To access the potential toxic effects that the different steps of soil management in these areas may cause, the cladoceran Ceriophania silvestrii was used as aquatic bioindicator, the dicot Eruca sativa as phytotoxicity bioindicator in water, and the dipteran Chironomus sancticaroli as sediment bioindicator. Generalized linear mixed models were used to identify differences between the treatments. Low concentrations of 2,4-D (<97 mu g L-1) and fipronil (<0.21 mu g L-1) in water were able to alter fecundity, female survival, and the intrinsic rate of population increase of C. silvestrii in IP and C treatments. Similarly, the dicot E. sativa had germination, shoot and root growth affected mainly by 2,4-D concentrations in the water. For C. sancticarolli, larval development was affected by the presence of fipronil (<402.6 ng g(-1)). The acidic pH (below 5) reduced the fecundity and female survival of C. silvestrii and affected the germination and growth of E. sativa. Fecundity and female survival of C. silvestrii decrease in the presence of phosphorus-containing elements. The outcomes of this study may improve our understanding of the consequences of exposure of freshwater biota to complex stressors in an environment that is rapidly and constantly changing.

期刊论文 2024-04-20 DOI: 10.1016/j.scitotenv.2024.171425 ISSN: 0048-9697
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