Toxicity Of Oil Research Articles

Toxicity of Black Pepper Oil and Piperine on Egg Hatchability of the European Corn Borer, Ostrinia nubilalis (Hubner) and Evaluate their Potential Phytotoxicity

Toxicity of Black Pepper Oil and Piperine on Egg Hatchability of the European Corn Borer, Ostrinia nubilalis (Hubner) and Evaluate their Potential Phytotoxicity

Toxicity of Clove Oil Nanoparticles against Diamondback Moth Plutella xylostella (L.)

Plutella xylostella, diamondback moth (DBM), has been one of the most challenging insects to control in the world to date. Environmentally friendly methods of control, such as the use of botanical insecticides, are available. A formulation that can sustain the main compound's level is required, which can be accomplished through soluble powder nanoformulation. The goal of this research was to test and evaluate the ability of clove oil nanoparticles produced from polyethylene glycol 6000 (PEG 6000) to control DBM utilizing a solid dispersion technique. Bioassay by leaf dip method in laboratory was used to test the lethal effect of clove oil nanoparticles (CO-NPs) on DBM. Clove oil nanoformulation was successful because it produced nanoparticles (179.98 nm in diameter) while maintaining high levels of the active component eugenol. Clove oil nanoparticles may increase clove oil's toxicity to DBM, seen from the LC50 value after 24 h of treatment. The LC50 values for clove oil nanoparticles after 24 and 48 h of treatment were 10.308 and 9.451%, respectively.

Chemical composition and toxicity of Artemisia herba-alba essential oil against Cydia pomonella L. (Lepidoptera:Tortricidae) under laboratory conditions

The codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) is a destructive pest of apples and pears worldwide. Due to the phytotoxic effect of chemical fumigant on postharvest apple, botanical insecticides are an interesting alternative to synthetic chemical insecticides regarding their low environmental impact. Hence, in the present study, we investigated the chemical composition and fumigant toxicity of Artemisia herba-alba essential oil against the fifth-instar codling moth, under laboratory conditions. In total, 49 compounds were identified by gas chromatography/mass spectrometry. The major constituents determined were dextro-camphor (30.60%), 2,6-dimethyl-1,3,6-heptatriene (26.71%), safranal (7.04%), borneol (3.94%) and eucalyptol (3.47%). A. herba-alba essential oil showed strong larvicidal activity, with minimum lethal concentration LC50 values of 13.49 and 04.45 μl L-1 air at 24 h and 48 h, respectively. The LT50 values at the lowest (1.81 μl L-1 air) and highest oil concentrations (18.18 μl L-1 air) were, in turn, 59.35 to 19.52 h. The obtained results indicated that essential oil of A. herba-alba may have a potential to be developed as a botanical fumigant against the fifth-instar codling moth.

Improving the design and conduct of aquatic toxicity studies with oils based on 20 years of CROSERF experience

Laboratory toxicity testing is a key tool used in oil spill science, spill effects assessment, and mitigation strategy decisions to minimize environmental impacts. A major consideration in oil toxicity testing is how to replicate real-world spill conditions, oil types, weathering states, receptor organisms, and modifying environmental factors under laboratory conditions. Oils and petroleum-derived products are comprised of thousands of compounds with different physicochemical and toxicological properties, and this leads to challenges in conducting and interpreting oil toxicity studies. Experimental methods used to mix oils with aqueous test media have been shown to influence the aqueous-phase hydrocarbon composition and concentrations, hydrocarbon phase distribution (i.e., dissolved phase versus in oil droplets), and the stability of oil:water solutions which, in turn, influence the bioavailability and toxicity of the oil containing media. Studies have shown that differences in experimental methods can lead to divergent test results. Therefore, it is imperative to standardize the methods used to prepare oil:water solutions in order to improve the realism and comparability of laboratory tests. The CROSERF methodology, originally published in 2005, was developed as a standardized method to prepare oil:water solutions for testing and evaluating dispersants and dispersed oil. However, it was found equally applicable for use in testing oil-derived petroleum substances. The goals of the current effort were to: (1) build upon two decades of experience to update existing CROSERF guidance for conducting aquatic toxicity tests and (2) to improve the design of laboratory toxicity studies for use in hazard evaluation and development of quantitative effects models that can then be applied in spill assessment. Key experimental design considerations discussed include species selection (standard vs field collected), test substance (single compound vs whole oil), exposure regime (static vs flow-through) and duration, exposure metrics, toxicity endpoints, and quality assurance and control.

Setting the stage to advance oil toxicity testing: Overview of knowledge gaps, and recommendations

The Chemical Response to Oil Spills: Ecological Effects Research Forum created a standardized protocol for comparing the in vivo toxicity of physically dispersed oil to chemically dispersed oil to support science-based decision making on the use of dispersants in the early 2000s. Since then, the protocol has been frequently modified to incorporate advances in technology; enable the study of unconventional and heavier oils; and provide data for use in a more diverse manner to cover the growing needs of the oil spill science community. Unfortunately, for many of these lab-based oil toxicity studies consideration was not given to the influence of modifications to the protocol on media chemistry, resulting toxicity and limitations for the use of resulting data in other contexts (e.g., risk assessments, models). To address these issues, a working group of international oil spill experts from academia, industry, government, and private organizations was convened under the Multi-Partner Research Initiative of Canada's Oceans Protection Plan to review publications using the CROSERF protocol since its inception to support their goal of coming to consensus on the key elements required within a “modernized CROSERF protocol”.

Advances to the CROSERF protocol to improve oil spill response decision making

The Chemical Response to Oil Spills: Ecological Effects Research Forum (CROSERF) created a standardized protocol for comparing the toxicity of physically dispersed oil versus chemically dispersed oil to address environmental concerns related to the proposed use of dispersants in the early 2000s. Since then, many revisions have been made to the original protocol to diversify the intended use of the data generated, incorporate emerging technologies, and to examine a wider range of oil types including non-conventional oils and fuels. Under the Multi-Partner Research Initiative (MPRI) for oil spill research under Canada's Oceans Protection Plan (OPP), a network of 45 participants from seven countries representing government, industry, non-profit, private, and academic sectors was established to identify the current state of the science and formulate a series of recommendations to modernize the oil toxicity testing framework. The participants formed a series of working groups, targeting specific aspects of oil toxicity testing, including: experimental conduct; media preparation; phototoxicity; analytical chemistry; reporting and communicating results; interpreting toxicity data; and appropriate integration of toxicity data to improve oil spill effects models. The network participants reached a consensus that a modernized protocol to assess the aquatic toxicity of oil should be sufficiently flexible to address a broad range of research questions in a ‘fit-for-purpose’ manner, where methods and approaches are driven by the need to generate scientifically-defensible data to address specific study objectives. Considering the many needs and varied objectives of aquatic toxicity tests currently being conducted to support and inform oil spill response decision making, it was also concluded that the development of a one size fits all approach would not be feasible.

Toxicity and biochemical effects of citronella, mustard and sage essential oils and their nanoemulsions against Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

Toxicity and biochemical effects of citronella, mustard and sage essential oils and their nanoemulsions against Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

Controlling Diels-Alder reactions in catalytic pyrolysis of sawdust and polypropylene by coupling CO2 atmosphere and Fe-modified zeolite for enhanced light aromatics production

Producing value-added light aromatics (BTEX) from solid waste streams holds excellent promise for resource recovery. Here we present a thermochemical conversion approach that enhanced BTEX production by coupling CO2 atmosphere and Fe-modified HZSM-5 zeolite to facilitate the Diels-Alder reactions in catalytic pyrolysis of sawdust and polypropylene. The Diels-Alder reactions between sawdust-derived furans and polypropylene-derived olefins could be controlled by tuning CO2 concentration and Fe loading amount. Sufficient CO2 (≥50%) with moderate Fe loading (10 wt%) were observed to produce more BTEX and fewer heavy fractions (C9+aromatics). To deepen the mechanistic understanding, quantification of polycyclic aromatic hydrocarbons (PAHs) and catalyst coke was further conducted. The co-use of CO2 atmosphere and Fe modification suppressed the appearance of low-, medium-, and high-membered ring PAHs by over 40%, decreased pyrolysis oil toxicity from 42.1 to 12.8 μg/goil TEQ, and transformed coke from "hard" to "soft". Based on the characterization of CO2 adsorption behavior, it was deduced that the introduced CO2 was activated by loaded Fe and reacted in situ with H2 generated during aromatization to expedite H-transfer. Meanwhile, BTEX recondensation was prevented through the Boudouard reactions of CO2 and water-gas reactions between the resulting water and carbon deposits. These synergistically enhanced the production of BTEX and suppressed the formation of heavy species, including PAHs and catalyst coke.

Valorization of clove (Syzygium aromaticum) by-products as potential stored grain protectants.

Clove (Syzygium aromaticum) being a most valuable spice, produce stems and leaves as by-products during processing. This study aimed to valorize these by-products as potential grain protectants against rice weevils since it is a novel approach to reducing the post-harvest loss of rice and minimizing synthetic insecticide usage. The composition of clove stem and leaf essential oils was analyzed using gas chromatography-mass spectrometry. Accordingly, the contact repellent activity and fumigation mortality of essential oils were tested while computing the mortality percentage and LD50 values. The yield of stem essential oil (5.52%) was significantly higher than leaf essential oil (3.92%). Further, stem essential oil with a 100µL dose showed the highest repellency (100.00 ± 0.00%) and mortality (96.67 ± 3.33%) while 50 and 75µL doses caused similar mortality (83.30 ± 3.33%) after 5days. The lowest LD50 (28.06µL/L) was observed on day 5, indicating the higher toxicity of stem essential oil. Eugenol (73.73 and 82.56%), β-caryophyllene (24.84 and 16.67%), α.-humulene (0.82 and 0.33%), and 1S, CIS-calamenene (0.14 and 0.03%) were detected as the major components responsible for the insecticidal activity of stem and leaf essential oils. Hence, the valorization of clove by-products was successful as potential grain protectants, and clove stem essential oil could be the most effective alternative for rice weevil management.

Assessment of dermal toxicity of mustard oil based formulation of Nerium indicum Mill.

Nerium indicum Mill. with red flowers belong to family Apocynaceae is considered as botanical source of Rakta Karavira drug of Upavisha (semi-poisonous) category of Ayurvedic Pharmacopeia of India. Till date Rakta Karavira Taila (mustard oil based formulation of root bark of Rakta Karavira) has not been evaluated pharmacologically. In present study, acute and repeated dose 28 day dermal toxicity studies of Rakta Karavira Taila was carried out in Charles foster albino rats. Acute dermal toxicity study was assessed at a single dermal application of drug at limit dose of 2000 mg/kg body weight of rats and observed for fourteen consecutive days. The repeated dose 28-day dermal toxicity study was assessed on repeated dermal applications at limit dose of 1000 mg/kg body weight of rats for 28 days consecutive days as per OECD guideline. The test medication was applied equally over a region covering rats body surface area of about 10%. Effects on body weight, haematological, ponderal changes, biochemical, and histological studies were used to evaluate the toxicity of the Rakta Karavira Taila. No mortality and toxicity were observed on single dermal application at limit dose level of 2000 mg/kg in acute dermal toxicity study. On repeated dermal applications of Rakta Karavira Taila at limit dose of 1000 mg/kg, showed statistically significant decrease in weight of testes, increase in WBC and platelet count while rest of hematological and biochemical parameters are not affected in comparison to control group. Histopathological study showed inflammation and fatty degenerative changes in liver and kidney, degenerative changes in seminiferous tubules and decrease in spermatogenesis in drug administered group. Medicated oil prepared out of root bark of Nerium indicum with red flower with mustard oil has potential to produce adverse effect particularly on male reproductive system therefore, should not be used for longer duration at higher dose level.

Bio-molluscicidal potential and biochemical mechanisms of clove oil and its main component eugenol against the land snail, Theba pisana

The land snail, Theba pisana is a serious pest that adversely affects various crops in sustainable agriculture. Essential oils and their constituents represent an environmentally sound alternative to synthetic pesticides. Our study aimed to investigate the lethal and sub-lethal toxicity of clove oil and its main component eugenol to understand the mechanisms underlying its toxic action against T. pisana. The GC–MS profile of the clove oil composition was characterized. In the laboratory experiment, LD50 of clove oil and eugenol via the contact testing were determined after 48 and 72 h. Moreover, sub-lethal effects of clove oil or eugenol on the survivors following the exposure of snails to the 25 and 50% of the LD50/48 and 72 h were evaluated through using snail tissues for biochemical measurments. The GC–MS analysis showed that eugenol (64.87%) was the major constituent present in the oil. The results also showed that LD50 values at 48 and 72 h were 2006.5 and 1493.5 μg/g b.w for oil and 239.6 and 195.3 μg/g b.w for eugenol, respectively. Compared to control, the sub-lethal effects of clove oil or eugenol at 48 and 72 h showed a significant increase in reduced glutathione (GSH) levels. Catalase (CAT) and glutathione-S-transferase (GST) activities significantly elevated in oil- or eugenol-treated snails, except at low dose after 48 h. After two exposure times, snails exposed to oil or eugenol at both sub-lethal effects had considerably higher γ-glutamyltransferase (γ-GT) and aspartate aminotransferase (AST) activities. Moreover, markedly augmentation in alkaline phosphatase (ALP) and alanine aminotransferase (ALT) activities at all exposure times, with the exception of snails treated with low dose of eugenol after 48 h was observed. Both clove oil and eugenol at the tested doses caused a significant inhibition in acetylcholinesterase (AChE) activity at two exposure times. Our findings highlight the potential of clove oil and eugenol, as an efficient natural molluscicide alternative to its synthetic counterparts for snail control.

Toxicity of insecticidal plant oils on the larval and adult stages of a major malaria vector (Anopheles gambiae Giles 1920)

Despite increasing reports and concerns about the development of resistance to public-health insecticides in malaria vectors, significant progress has been made in the search for alternative strategies to disrupt the disease transmission cycle by targeting insect vectors and thus sustaining vector management. The use of insecticidal plants is a strategy that can be employed and this study investigates the toxicity potential of insecticidal plant oils shortlisted in an ethnobotanical survey on Anopheles gambiae larvae and adult stages. The shortlisted plants parts, the leaves of Hyptis suaveolens, Ocimum gratissimum, Nicotiana tabacum, Ageratum conyzoides, and Citrus sinensis fruit-peel were collected and extracted using a Clevenger apparatus. Larvae and female adults of deltamethrin-susceptible Anopheles gambiae were obtained from an already-established colony at the University of Ilorin's Entomological Research Laboratory. In five replicates, twenty-five third instar stage larvae were used for larvicidal assays and twenty 2-5days old adults were used for adulticidal assays. After 24h, An. gambiae exposed to Hy. suaveolens and Ci. sinensis exhibited significantly higher larval toxicity (94.7-100%). The mortality induced by the oils of the four plants peaked at 100% after 48h. Ni. tabacum (0.50mg/ml) induced the highest percentage of adult mortality on An. gambiae (100%) when compared to the positive control Deltamethrin (0.05%). The lowest KdT50 was observed with 0.25mg/ml of Ni. tabacum (20.3min), and the lowest KdT95 was observed with 0.10mg/ml of Ag. conyzoides (35.97min) against adult An. gambiae. The evaluated plant oils demonstrated significant larval and adult mortality rates, lower lethal concentrations, and knockdown times, indicating promising results that can be further developed for malaria vector management.

The influence of temperature in sea urchin embryo toxicity of crude and bunker oils alone and mixed with dispersant

This investigation deals with how temperature influences oil toxicity, alone or combined with dispersant (D). Larval lengthening, abnormalities, developmental disruption, and genotoxicity were determined in sea urchin embryos for assessing toxicity of low-energy water accommodated fractions (LEWAF) of three oils (NNA crude oil, marine gas oil –MGO-, and IFO 180 fuel oil) produced at 5–25 °C. PAH levels were similar amongst LEWAFs but PAH profiles varied with oil and production temperature. The sum of PAHs was higher in oil-dispersant LEWAFs than in oil LEWAFs, most remarkably at low production temperatures in the cases of NNA and MGO. Genotoxicity, enhanced after dispersant application, varied depending on the LEWAF production temperature in a different way for each oil. Impaired lengthening, abnormalities and developmental disruption were recorded, the severity of the effects varying with oil, dispersant application and LEWAF production temperature. Toxicity, only partially attributed to individual PAHs, was higher at lower LEWAF production temperatures.

Efficacy and toxicity of anise oil as a potential topical wound healer: a cell culture study.

We studied the cytotoxic effects of topical anise oil on NIH/3T3 fibroblast cells using a cell culture assay. NIH/3T3 fibroblast cells were grown in Dulbecco's Modified Eagle Medium (DMEM) supplemented with fetal bovine serum (10%) and penicillin/streptomycin under standard cell culture conditions in a humidified incubator containing 5% carbon dioxide. For the MTT cytotoxicity experiment, NIH/3T3 cells were plated in triplicate at a concentration of 3x103 per well in 96-well plates and incubated for 24 hours. The cells were treated with anise oil concentrations ranging from 3.13 to 100 μM, and the plates were cultured for 24, 48, and 72 hours under standard cell culture conditions. For assessment by confocal microscopy, NIH/3T3 cells were seeded on sterilized coverslips in 6-well plates at a concentration of 105 cells per well in triplicate. For 24 hours, cells were treated with 100 μM of anise oil. Three wells that were not treated with anise oil served as the control group. The MTT findings demonstrated that anise oil is not cytotoxic to NIH/3T3 fibroblast cells. Anise oil stimulated cell growth and triggered cell division at all three incubation intervals of 24, 48, and 72 hours. The maximum growth was obtained in the applied highest concentration of 100 μM anise oil. At doses of 25, 50, and 100 μM, there was also a statistically significant improvement in cell viability. At 72 hours of incubation, dosages of 6.25 and 12.5 micro of anise oil were shown to be viability-inducing for NIH/3T3 cells. In the confocal microscopy pictures, it was found that anise oil was not cytotoxic on NIH/3T3 cells at the applied maximal dose. The experimental group of NIH/3T3 cells exhibited the same cell morphology as the untreated control group. In both sets of NIH/3T3 cells, the nucleus was round and undamaged, and the cytoskeleton was determined to be compact. Anise oil is not cytotoxic on NIH/3T3 fibroblast cells and initiates cell growth. Anise oil could be used topically to enhance wound healing after surgical procedures if clinical trials will confirm experimental data.

Retinal Toxicity of Silicone Oil

Polydimethylsiloxane, known as silicone oil, belongs to a group of polymeric organosilicon compounds and is widely used in vitreoretinal surgery.

Effects of Piper nigrum L. Fruit Essential Oil Toxicity against Stable Fly (Diptera: Muscidae).

The efficacy of Piper nigrum L. fruit essential oil (EO) against Stomoxys calcitrans (stable fly), a blood-feeding fly distributed worldwide, was investigated. This study aimed to evaluate the insecticidal activity of EO based on contact and fumigant toxicity tests. Chemical analysis of the EO using gas chromatography-mass spectrometry revealed that sabinene (24.41%), limonene (23.80%), β-caryophyllene (18.52%), and α-pinene (10.59%) were the major components. The results demonstrated that fly mortality increased with increasing EO concentration and time during the first 24 h of exposure. The median lethal dose was 78.37 µg/fly for contact toxicity, while the 90% lethal dose was 556.28 µg/fly. The median lethal concentration during fumigant toxicity testing was 13.72 mg/L air, and the 90% lethal concentration was 45.63 mg/L air. Our findings suggested that essential oil extracted from P. nigrum fruit could be a potential natural insecticidal agent for control of stable fly. To examine the insecticidal properties of P. nigrum fruit EO, further field trials and investigation into the efficacy of nano-formulations are required.

Fumigant toxicity of some plant volatile oils against stored grain weevils

Fumigant toxicity of some plant volatile oils against stored grain weevils

Duguetia lanceolata A. St.-Hil. (Annonaceae) Essential Oil: Toxicity against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and Selectivity for the Parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae)

The fall armyworm (FAW) Spodoptera frugiperda is a polyphagous pest that is difficult to control due to populations resistant to various active ingredients. Thus, the objective of this study was to evaluate the toxicity of essential oils (EOs) from the organs of Annona neolaurifolia, Duguetia lanceolata, and Xylopia brasiliensis, against the FAW and its natural enemy, Trichogramma pretiosum. The most active EOs were those from the leaves and stem bark of D. lanceolata, which presented LD90 to S. frugiperda equal to 70.76 and 127.14 µg of EO/larvae, respectively. The major compounds in the EO of D. lanceolata (leaves) were β-caryophyllene and caryophyllene oxide. Although individually inactive against the FAW, when combined, those compounds reduced the insect’s probability of survival. However, the mortality was lower than that caused by EO. This result suggests that other components of EO contribute to the activity against FAW. Furthermore, the EO of the leaves from D. lanceolata presented low toxicity to the egg-larva stage of T. pretiosum, but was toxic to other phases. Thus, EO from D. lanceolata is potentially useful for developing new products to control S. frugiperda.

Low Concentrations of Eucalyptus Essential Oil Induce Age, Sex, and Mating Status-Dependent Stimulatory Responses in Drosophila suzukii

Plant-extracted essential oils are generally suggested as potential sources for alternatives to synthetic insecticides in insect pest control strategies. The increased interest in the use of essential oils derives from the generalized perception of their safety for the environment, human health, and non-target organisms as well as a lower risk of resistance development. However, studies on essential oils have largely focused on their activity on targeted insect pests while overlooking their potential unintended effects on insect biological and reproductive traits, especially with sublethal exposures. Here, we first determined the toxicity of Eucalyptus globulus essential oil to adults of Drosophila suzukii and assessed the effects of low concentrations (i.e., LC5 and LC20) in old (5–7 days) and mated flies. Subsequently, we assessed longevity and fecundity in newly emerged virgin flies from four couples’ combinations: unexposed couples, exposed females, exposed males, and exposed couples to the low concentration LC20. Our results show that eucalyptus essential oil has good insecticidal activity against adults of D. suzukii. However, compared to untreated flies, the exposure to low concentrations enhanced the females’ fecundity only when both old and mated female and male flies were exposed, while the females’ but not males’ life span was extended only in couples where newly emerged virgin females were exposed. Our findings suggest that although the eucalyptus essential oil may be a good control alternative for adult D. suzukii, its age-, sex-, and mating status-dependent stimulatory responses mediated by exposure to low concentrations need to be considered and further investigated.

Comparative toxicity of essential oils, their emulsifiable concentrates and nanoemulsion formulations against the bean aphid, Aphis fabae

The present study aims to prepare emulsifiable concentrate (EC) and nanoemulsion formulations from the plant essential oils of Lavandula angustifolia (Mill.), Ambrosia maritima (L.), Commiphora myrrha (Nees) Engl., Juniperus virginiana (L.), Rheum palmatum (L.) and Tagetes minuta (L.). The efficiency of these essential oils along with their formulations were compared against the bean aphid, Aphis fabae (Scopoli). Results disclosed that all EC preparations passed the emulsion stability and foam formation tests. The particle droplet size of the nanoemulsions varied from 64.3 to 264.7 nm. The toxicity of EC formulations was slightly higher than the corresponding nanoemulsion formulations. Both EC and nanoemulsion of R. palmatum were the most efficient (LC50 = 1003.60 and 1105.34 mg L−1, respectively). EC preparations had no adverse effects on seed beans. The absence of organic solvents and the high aphicidal activity of EC formulations might make these preparations suitable for controlling A. fabae.