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Understanding the penetration behaviour of pesticide active ingredient (AI) in the presence of adjuvants is important in managing application efficacy and minimizing residues. This study investigates the impact of non-ionic surfactant alkylphenol ethoxylates (APEOs) on the penetration of two pesticides, systemic thiabendazole and non-systemic phosmet, in apple and spinach. Surface-enhanced Raman Spectroscopy (SERS) was employed using two different detection methods, namely XZ depth mapping and XY area mapping, in conjunction with liquid Chromatography with tandem mass spectrometry (LC-MS/MS) to investigate the penetration of various pesticide formulations over time. The SERS results showed that APEOs significantly increased the penetration depth of thiabendazole by 93.3 % in spinach and 21.4 % in apples, as well as enhanced the characteristic peak intensity by 73.52 % in spinach and 152.24 % in apples at the depth level of -60 µm after 3-day exposure. LC-MS/MS confirmed the consistent increases in internal thiabendazole residues in both fresh produce models due to APEOs. However, APEOs did not affect the penetration of the non-systemic phosmet in either apple or spinach. The combination of these two SERS mapping methods can provide a comprehensive understanding of the penetration profiles of different systemic pesticide formulations at various sensoria. This research advances the application of SERS mapping for studying the impact of nonionic surfactants on pesticide penetration which will aid the development of strategies to improve pesticide application efficiency and enhance food safety., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Background and Aims: Cannabigerol (CBG) is a nonintoxicating cannabinoid synthesized in the Cannabis sativa plant that is incorporated into dietary supplements. This study investigated the influence of dietary fat and an emulsified delivery vehicle on CBG pharmacokinetics (PKs) after oral ingestion by adults. Materials and Methods: Consented participants were enrolled in a double-crossover pilot study and were blinded to the delivery vehicle type (isolate or emulsification) and isocaloric meal condition (low-fat=<5 g fat/meal or high-fat [HF]=>30 g fat/meal). The concentration of CBG in human plasma was measured after a single 25 mg dose of CBG using liquid chromatography-tandem mass spectrometry (LC-MS/MS). PK parameters were calculated using noncompartmental analysis. Results: The PKs of the two delivery systems (emulsified vs. non-emulsified) were significantly impacted by the HF meal condition. Participants in the HF meal group exhibited significantly higher area under the plasma concentration time curve from time 0 to last quantifiable value, maximum concentration, and terminal half-life. Participants in the HF meal group also had a significantly lower terminal elimination rate constant and time to maximum concentration ( T max ), in addition to decreased T max variation. The threshold for bioequivalence between conditions was not met. An exploratory aim correlated anthropometric measures and previous day's dietary intake on PK parameters which yielded inconsistent results across dietary fat conditions. Conclusions: In aggregate, dietary fat had a greater effect on CBG PKs than the emulsified delivery vehicle. This supports accounting for dietary intake in development of therapeutics and administration guidelines for orally delivered CBG.

Perfluorooctanesulfonic acid (PFOS) is a ubiquitous legacy environmental contaminant detected broadly in human samples and water supplies. PFOS can cross the placenta and has been detected in cord blood and breastmilk samples, underscoring the importance of understanding the impacts of maternal PFOS exposure during early development. This study aimed to investigate the effects of a preconception exposure to PFOS on developmental endpoints in offspring, as well as examine the role of the transcription factor Nuclear factor erythroid-2-related factor (Nrf2a) in mediating these effects. This transcription factor regulates the expression of several genes that protect cells against oxidative stress including during embryonic development. Adult female zebrafish were exposed to 0.02, 0.08 or 0.14 mg/L PFOS for 1 week (duration of one cycle of oocyte maturation) and then paired with unexposed males from Nrf2a mutant or wildtype strains. Embryos were collected for two weeks or until completion of 5 breeding events. PFOS was maternally transferred to offspring independent of genotype throughout all breeding events in a dose-dependent manner, ranging from 2.77 to 23.72 ng/embryo in Nrf2a wildtype and 2.40 to 15.80 ng/embryo in Nrf2a mutants. Although embryo viability at collection was not impacted by maternal PFOS exposure, developmental effects related to nutrient uptake, growth and pancreatic β-cell morphology were observed and differed based on genotype. Triglyceride levels were increased in Nrf2a wildtype eggs from the highest PFOS group. In Nrf2a wildtype larvae there was a decrease in yolk sac uptake while in Nrf2a mutants there was an increase. Additionally, there was a significant decrease in pancreatic β-cell (islet) area in wildtype larvae from the 0.14 mg/L PFOS accompanied by an increase in the prevalence of abnormal islet morphologies compared to controls. Abnormal morphology was also observed in the 0.02 and 0.08 mg/L PFOS groups. Interestingly, in Nrf2a mutants there was a significant increase in the pancreatic β-cell area in the 0.02 and 0.08 mg/L PFOS groups and no changes in the prevalence of abnormal islet morphologies. These results suggest that the regulation of processes like nutrient consumption, growth and pancreatic β-cell development are at least partially modulated by the presence of a functional Nrf2a transcriptomic response. Overall, preconception exposure to environmental pollutants, such as PFOS, may impact the maturing oocyte and cause subtle changes that can ultimately impact offspring health and development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Since the voluntary phaseout of perfluorooctanesulfonic acid (PFOS), smaller congeners, such as perfluorobutanesulfonic acid (PFBS) have served as industrial replacements and been detected in contaminated aquifers. This study sought to examine the effects of a maternal preconception PFBS exposure on the development of eggs and healthy offspring. Adult female zebrafish received a one-week waterborne exposure of 0.08, 0.14, and 0.25 mg/L PFBS. After which, females were bred with non-exposed males and embryos collected over 5 successful breeding events. PFBS concentrations were detected in levels ranging from 99 to 253 pg/embryo in the first collection but were below the limit of quantitation by fourth and fifth clutches. Therefore, data were subsequently binned into early collection embryos in which PFBS was detected and late collections, in which PFBS was below quantitation. In the early collection, embryo 24 h survival was significantly reduced. In the late collection, embryo development was impacted with unique patterns emerging between Nrf2a wildtype and mutant larvae. Additionally, the impact of nutrient loading into the embryos was assessed through measurement of fatty acid profiles, total cholesterol, and triglyceride content. There were no clear dose-dependent effects, but again unique patterns were observed between the genotypes. Preconception PFBS exposures were found to alter egg and embryo development, which is mediated by direct toxicant loading in the eggs, nutrient loading into eggs, and the function of Nrf2a. These findings provide insight into the reproductive and developmental effects of PFBS and identify maternal preconception as a novel critical window of exposure., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Drinking water contamination related to the use of aqueous film-forming foam (AFFF) has been documented at hundreds of military bases, airports, and firefighter training facilities. AFFF has historically contained high levels of long-chain per- and polyfluoroalkyl substances (PFAS), which pose serious health concerns. However, the composition and toxicity of legacy AFFF mixtures are unknown, presenting great uncertainties in risk assessment and affected communities., Objectives: This study aimed to determine the fluorinated and nonfluorinated chemical composition of a legacy AFFF sample and its toxicity in zebrafish embryos., Methods: A sample of legacy AFFF (3% application formulation, manufactured before 2001) was provided by the Massachusetts Department of Environmental Protection. High resolution mass spectrometry (HRMS) was used to identify PFAS and nonfluorinated compounds, and a commercial laboratory measured 24 PFAS by a modified U.S. EPA Method 537.1. AFFF toxicity was assessed in zebrafish embryos in comparison with four major constituents: perfluorooctanesulfonic acid (PFOS); perfluorohexanesulfonic acid (PFHxS); sodium dodecyl sulfate (SDS); and sodium tetradecyl sulfate (TDS). End points included LC 50 values, and sublethal effects on growth, yolk utilization, and pancreas and liver development., Results: We identified more than 100 PFAS. Of the PFAS detected, PFOS was measured at the highest concentration ( 9,410 mg / L ) followed by PFHxS ( 1,500 mg / L ). Fourteen nonfluorinated compounds were identified with dodecyl sulfate and tetradecyl sulfate the most abundant at 547.8 and 496.4 mg / L , respectively. An LC 50 of 7.41 × 10 - 4 % AFFF was calculated, representing a dilution of the 3% formulation. TDS was the most toxic of the constituents tested but could not predict the AFFF phenotype in larval zebrafish. PFOS exposure recapitulated the reduction in length but could not predict effects on development of the liver, which was the tissue most sensitive to AFFF., Discussion: To our knowledge, this research is the first characterization of the chemical composition and toxicity of legacy AFFF, which has important implications for regulatory toxicology. https://doi.org/10.1289/EHP6470.

Understanding the behavior of pesticide translocation is significant for effectively applying pesticides and reducing pesticide exposures from treated plants. Herein, we applied surface enhanced Raman spectroscopy (SERS) for real-time monitoring of pesticide translocation in tomato plant tissues, including leaves and flowers, following root exposure in hydroponic and soil systems. Various concentrations of the systemic pesticide, thiabendazole, was introduced into hydroponic systems used for growing tomato plants. At selected time intervals, tomato leaves and flowers were picked and thiabendazole was measured directly under a Raman microscope after pipetting gold nanoparticle-containing solution onto the plant tissue. We found that the pesticide signals first appeared along the midrib in the lowest leaves and moved distally to the edge of the leaves. As the concentration of pesticide applied to the root was increased, the time necessary to detect the signal was decreased. The SERS surface mapping method was also able to detect thiabendazole in the trichomes of the leaves. In addition, we found a unique SERS peak at 737 cm -1 on both leaves and flowers at 4 and 6 days following the application of 200 mg/L thiabendazole to the hydroponic system. This peak appears to be coming from adenine-containing materials and may be related to the plant's response to pesticide toxicity, which could be used as a potential marker for monitoring plant responses to stresses. These results demonstrate a successful application of SERS as a rapid and effective way to study the real-time translocation behavior of pesticides in a plant system.

Removal of pesticide residues from fresh produce is important to reduce pesticide exposure to humans. This study investigated the effectiveness of commercial and homemade washing agents in the removal of surface and internalized pesticide residues from apples. Surface-enhanced Raman scattering (SERS) mapping and liquid chromatography tandem mass spectrometry (LC-MS/MS) methods were used to determine the effectiveness of different washing agents in removing pesticide residues. Surface pesticide residues were most effectively removed by sodium bicarbonate (baking soda, NaHCO 3 ) solution when compared to either tap water or Clorox bleach. Using a 10 mg/mL NaHCO 3 washing solution, it took 12 and 15 min to completely remove thiabendazole or phosmet surface residues, respectively, following a 24 h exposure to these pesticides, which were applied at a concentration of 125 ng/cm 2 . LC-MS/MS results showed, however, that 20% of applied thiabendazole and 4.4% of applied phosmet had penetrated into the apples following the 24 h exposure. Thiabendazole, a systemic pesticide, penetrated 4-fold deeper into the apple peel than did phosmet, a non-systemic pesticide, which led to more thiabendazole residues inside the apples, which could not be washed away using the NaHCO 3 washing solution. This study gives us the information that the standard postharvest washing method using Clorox bleach solution for 2 min is not an effective means to completely remove pesticide residues on the surface of apples. The NaHCO 3 method is more effective in removing surface pesticide residues on apples. In the presence of NaHCO 3 , thiabendazole and phosmet can degrade, which assists the physical removal force of washing. However, the NaHCO 3 method was not completely effective in removing residues that have penetrated into the apple peel. The overall effectiveness of the method to remove all pesticide residues diminished as pesticides penetrated deeper into the fruit. In practical application, washing apples with NaHCO 3 solution can reduce pesticides mostly from the surface. Peeling is more effective to remove the penetrated pesticides; however, bioactive compounds in the peels will become lost too.