A permethrin metabolite is associated with adaptive immune responses in Gulf War Illness

Gulf War Illness (GWI), affecting 30% of veterans from the 1991 Gulf War (GW), is a multi-symptom illness with features similar to those of patients with autoimmune diseases. The objective of the current work is to determine if exposure to GW-related pesticides, such as permethrin (PER), activates peripheral and central nervous system (CNS) adaptive immune responses. In the current study, we focused on a PER metabolite, 3-phenoxybenzoic acid (3-PBA), as this is a common metabolite previously shown to form adducts with endogenous proteins. We observed the presence of 3-PBA and 3-PBA modified lysine of protein peptides in the brain, blood and liver of pyridostigmine bromide (PB) and  PER (PB+PER) exposed mice at acute and chronic post-exposure timepoints. We tested whether 3-PBA-haptenated albumin (3-PBA-albumin) can activate immune cells since it is known that chemically haptenated proteins can stimulate immune responses. We detected autoantibodies against 3-PBA-albumin in plasma from PB + PER exposed mice and veterans with GWI at chronic post-exposure timepoints. We also observed that in vitro treatment of blood with 3-PBA-albumin resulted in the activation of B- and T-helper lymphocytes and that these immune cells were also increased in blood of PB + PER exposed mice and veterans with GWI. These immune changes corresponded with elevated levels of infiltrating monocytes in the brain and blood of PB + PER exposed mice which coincided with alterations in the markers of blood-brain barrier disruption, brain macrophages and neuroinflammation. These studies suggest that pesticide exposure associated with GWI may have resulted in the activation of the peripheral and CNS adaptive immune responses, possibly contributing to an autoimmune-type phenotype in veterans with GWI

Phytochemical Profiling and Antioxidant Capacity of Traditional Plants, Northern Thailand

Traditional plants have played a significant role in human culture and medicine throughout history. These plants have the capability to synthesize a diverse range of chemical compounds that serve essential biological functions. This study’s objective was to analyze the phytochemical composition of five traditional plants, namely Emilia sonchifolia, Chloranthus erectus, Caesalpinia mimosoides, Acacia concinna, and Tacca chantrieri, native to northern Thailand, using LC-QTOF/MS analysis and assess their potential bioactivity through various assays including DPPH radical scavenging activity, ABTS radical scavenging activity, ferric ion reducing antioxidant power, total phenolic compounds, and total flavonoid content. The findings revealed the presence of natural bioactive compounds in each plant extract, which exhibited pharmacological activity. Notably, Caesalpinia mimosoides displayed the highest antioxidant capacity across all plant extracts (IC50 in DPPH with the methanol extract was 0.03 and 898.18 mg AAE/100 g with the ethanol extract), along with elevated levels of total phenolic and flavonoid content, which showed the highest TFC at 46.79 µgRE/g in the methanol extract. In conclusion, traditional plants possess notable biological constituents and antioxidant properties, suggesting their potential for bioactive applications. Based on these findings, these indigenous plants can serve as a valuable resource in traditional medicine, offering the possibility of uncovering new products with similar capabilities and additional therapeutic attributes worthy of future exploration

Organophosphate Pesticide Exposures in Early and Late Pregnancy Influence Different Aspects of Infant Developmental Performance

Organophosphate (OP) pesticides can transfer from mother to fetus via the placenta and amniotic fluid and may affect the development of infants. This study aims to evaluate the associations between maternal OP concentrations collected in the 1st–2nd trimester and the 3rd trimester of pregnancy and the infant developmental performance. The Screening Test of the Bayley Scales of Infants and Toddler Development, Third Edition (BSID–III screening test) was used to assess development performance at 2 and 6 months of age. Multiple regression analysis showed a negative correlation between cognitive performance at 2 months and maternal diethylthiophosphate (DETP) levels in the 1st–2nd trimester (β ± SE = −0.012 ± 0.004, p < 0.05). We also found that expressive communication and fine motor performance at 6 months were negatively associated with maternal diethyldithiophosphate (DEDTP) levels in the 3rd trimester (β ± SE = −0.047 ± 0.016, p < 0.05, and β ± SE = −0.044 ± 0.017, p < 0.05, respectively). These results suggest that maternal ethylated OP concentrations at different timing of exposure during pregnancy may influence different aspects of infant developmental performance

Dopamine as a polymerizable reagent for enzyme-linked immunosorbent assay using horseradish peroxidase

We demonstrate that dopamine can be used as a reagent for colorimetric enzyme-linked immunosorbent assay (ELISA) using horseradish peroxidase (HRP). Dopamine was able to be polymerized in the presence of HRP and H2O2, and black polydopamine was obtained after the enzymatic reaction. Because of the black color, the absorbance was significantly changed in the whole range of the visible light region. Here, an indirect competitive ELISA based on the polymerization of dopamine was performed to detect a fluoroquinolone antibiotic, enrofloxacin. The antibiotic is commonly used in livestock farming. The anti-antibiotics antibody was produced from egg yolk from chicken hens. In the visible range, sufficient absorbance changes of ∼0.4∼0.5 and a low background level for the ELISA response were obtained, and the 50 % inhibitory concentration value at 450 nm was determined to be 26 ppb. The performance of the indirect competitive ELISA based on the polymerization of dopamine was compared to that based on the oxidation of catechol because dopamine has a catechol skeleton. By the complex of HRP and H2O2, catechol can be oxidized to o-benzoquinone having a maximum absorption wavelength of 420 nm. It was shown that the absorbance change in the case of polydopamine was about 2.5 times higher than that of catechol, where the background levels were similar. This confirms that the polymerization of dopamine significantly enhanced the photosignal

The Assessment of Organophosphate Pesticide Exposure among School Children in Four Regions of Thailand: Analysis of Dialkyl Phosphate Metabolites in Students’ Urine and Organophosphate Pesticide Residues in Vegetables for School Lunch

In Thailand, pesticides containing organophosphates (OP) are frequently applied to crops to suppress insects. School children can be exposed to OPs on a daily basis, from food consumption to breathing and touching pesticides drifted near classrooms. Living in an agricultural area can also be one of the causes. As a result, it is important to monitor OPs residues in the food chain and biomarkers of exposure. The Gas Chromatography–Flame Photometric Detector method was employed to examine the relationship between OPs residue and DAPs (Diakly phosphate) in four targeted locations in Thailand, as well as to examine the residues of OPs in vegetable samples and DAPs in 395 school children’s urine samples. Vegetables were found to contain at least one OP, with chlorpyrifos being the most prevalent. The OPs detected frequencies for Sakon Nakhon, Chiang Mai, Phang Nga, and Pathum Thani are 96.1%, 94%, 91.7%, and 83.3%, respectively. The overall centration level of OPs showed 0.3261 mg/kg, 0.0636 mg/kg, 0.0023 mg/kg, 0.0150 mg/kg, 0.2003 mg/kg, 0.0295 mg/kg, and 0.0034 mg/kg for diazinon, dimethoate, pirimiphos-methyl, chlorpyrifos, profenofos, ethion, and triazophos, respectively. Nearly 98% of school children were detected with at least one DAP. The overall level of dimethyl phosphate metabolites (5.258 µmole/mole creatinine) in urine samples is higher than diethyl phosphate metabolites (2.884 µmole/mole creatinine), especially in the case of Pathum Thani. Our findings show a consistent relationship between OPs in vegetables from wet markets and DAPs in urine samples of school children in various parts of Thailand

Pesticide Use under Public Good Agricultural Practices Standard: A Comparative Study in Thailand

The local implementation of Thailand’s public good agricultural practices (GAP) certification standard was investigated by examining its effectiveness in raising farmers’ awareness, lowering pesticide use, and thus improving food safety and quality assurance. A total of 98 certified and 100 uncertified farms were surveyed in two Thai provinces, Chanthaburi and Nakhon Si Thammarat, respectively. Considering durian (Durio zibethinus Murr.) cultivation, the economic size of farming in the former region is relatively larger and production more market-oriented, while in the latter region, the farming scale is smaller. It was observed that knowledge and understanding of GAP is much higher among the certified as compared to the uncertified farmers, although the effectiveness of GAP in lowering pesticide use remains unconfirmed. The comparison between the two regions also suggests that farmers’ pesticide use could be affected by other contextual factors to a greater extent than the GAP. Results from a multivariate linear regression analysis highlighted the critical importance of training on Q-GAP and pesticide use in reducing pesticide use among certified farmers. This suggests that GAP applicant farmers should be encouraged to participate in training on those subjects as an integral part of their Q-GAP application or renewal procedure

Producers’ Perceptions of Public Good Agricultural Practices Standard and Their Pesticide Use: The Case of Q-GAP for Cabbage Farming in Chiang Mai Province, Thailand

This study examined the effectiveness of Thailand’s Q-GAP initiative in raising cabbage farmers’ awareness regarding food safety assurance and improving their pesticide use practices by comparing 41 Q-GAP-certified and 90 uncertified farmers in Chiang Mai Province, Thailand. The research methods included a questionnaire survey administered to the participating farmers and laboratory pesticide residue testing of their cabbage produce samples. The research found that certified farmers had a significantly more heedful attitude than uncertified farmers toward the effects of pesticide use on the users, consumers, and the environment. This is supported by the higher level of Q-GAP training experiences. Compared to uncertified farmers, a significantly lower proportion of certified farmers also applied either insecticide, fungicide, or herbicide, with significantly less frequencies when including in the analysis those who did not use the particular pesticide. In the pesticide residue analysis, no significant difference was found between the two types of farms regarding the number of farms detected with maximum residue level exceedance in the sample produce and regarding the results of the aggregate organophosphate pesticide analysis. However, it was found that the produce of the uncertified farmers contained significantly more residue in the aggregate synthetic pyrethroid pesticide analysis as compared to that of the certified farmers. These findings indicate the Q-GAP-certified farmers’ progress in process control from earlier Q-GAP studies on compliance. However, considering the limited achievements of certified farmers in pesticide handling and recordkeeping, and those of the Department of Agriculture officers in auditing, there is a need for more governmental efforts, especially in these areas

How to protect agricultural workers from exposure to pesticides: Effectiveness of woven and natural resin-coated fabrics

Agricultural workers in low and middle-income countries usually wear their everyday clothing made of woven fabrics during pesticide application. Different characteristics of various woven fabrics have different abilities to prevent the penetration of pesticides through to the skin. Therefore, the ultimate goal of this study is that agricultural workers in Thailand can choose a suitable fabric of protective clothing to protect themselves from pesticide exposure. This study aims to investigate pesticide penetration levels in different woven fabrics, and to explore factors affecting levels of pesticide penetration through fabrics. In addition, our study aims to produce cotton fabrics coated with a natural resin to obtain water-repellent characteristics and evaluate their effectiveness in protecting against pesticides. Four pesticides used in the testing process were chlorpyrifos, cypermethrin, paraquat, and glyphosate. The results found that a suitable fabric to protect agricultural workers from pesticide exposure is a fabric which made of 100% cotton and have greater weight. With regard to natural resin-coated fabrics, fabric C1-R showed the highest levels of effectiveness in protecting against the pesticides (range between 89%-95%). The natural resin-coated fabric is an alternative fabric in the protection against pesticides for agricultural workers in low and middle-income countries when commercial PPE are prohibitively expensive