Background and Aim Biomarkers of pesticide exposure are generally lacking in communities where agricultural crops are grown. The purpose of this study was to focus on evaluating biomarkers of pesticide exposure in people living in an agricultural area of San Pa Tong District in Chiang Mai Province, northern Thailand. Materials and Methods One hundred and twenty-four participants (38 nonfarm workers, 38 rice growers, 31 longan growers, and 17 vegetable growers) from San Pa Tong District gave consent to participate in the study. Pesticide exposure was assessed by determining acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) levels in blood samples using Ellman's method and measuring 6-dialkylphosphate metabolites (DAPs), 3-phenoxybenzoic acid (3-PBA), and glyphosate in urine samples using chromatographic methods. Results AChE and BChE activities in the nonfarm worker group had higher level than those in the grower groups. DAPs were detected in almost all urine samples and 3-PBA was detected in 12-45% of each group, while glyphosate was found in 11 – 30% among the three groups of growers but not in nonfarm workers. Conclusion In this study, participants living in an agricultural area of San Pa Tong District were exposed to organophosphate, synthetic pyrethroid, and glyphosate through multiple pathways.

The Smilacaceae family has been used as a food source and herbal medicine for a long time. This study aims to identify the phytochemicals extracted from Smilax glabra and Smilax corbularia by using LC-QTOF/MS analysis and determine their bioactive potential. Compounds were identified from S. glabra and S. corbularia extracts by LC–QTOF-MS and it was found that longistylin A and CAY10435 have higher degrees of matching compounds (99.66% and 99.87%). Smilax glabra showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 71.94 ± 1.46% and 59.84 ± 4.80%, respectively, and FRAP at 730.69 ± 33.62 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.017 ± 0.001, 0.015 ± 0.001, and 0.016 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents were 0.043 ± 0.002, 0.033 ± 0.002, and 0.006 ± 0.003 mg QE/g, respectively. The anti-inflammatory capacity showed 97.26% protection and 2.74% hemolysis. The antimicrobial activity can inhibit Gram-positive bacteria with a minimum inhibitory concentration (MIC) of 62.5 mg/mL and a minimum bactericidal concentration (MBC) of 500 mg/mL. Smilax corbularia showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 72.24 ± 0.64% and 39.87 ± 2.37%, respectively, and FRAP at 208.33 ± 50.80 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.006 ± 0.000, 0.007 ± 0.002, and 0.002 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents of the ethanol and methanol extracts were 0.012 ± 0.001 and 0.008 ± 0.000 mg QE/g, respectively. The anti-inflammatory capacity showed 96.64% protection and 3.36% hemolysis. The antimicrobial activity of the extracts can inhibit Gram-positive bacteria with a MIC of 31.25 mg/mL and MBC of 125 mg/mL for the ethanol extract and a MIC of 125 mg/mL and MBC of 62.5 mg/mL for the methanol extract. In conclusion, Smilax glabra and Smilax corbularia were found to contain several phytochemicals that can be used for further study. Both Smilax species can also be used as sources of antioxidants and herbal medicines for killing Gram-positive bacteria.

Amyloid beta peptides (Aβ1-42) have been found to be associated with the cause of Alzheimer’s disease (AD) and dementia. Currently, methods for detecting Aβ1-42 are complicated and expensive. The present study is aimed at developing an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) to detect Aβ1-42 by using a polyclonal antibody from alpaca, an application used in urine samples. The serum was collected from the alpaca after immunizing it with Aβ1-42 at 500 μg/injection 5 times. The ic-ELISA was developed and showed a half-maximal inhibitory concentration ( I C 50 ) of 103.20 ng/ml. The limit of detection (LOD) was 0.39 ng/100 μl. The cross-reactivity was tested with Aβ1-40 and 8 synthesized peptides that had sequence similarities to parts of Aβ1-42. The cross-reactivity of Aβ1-40 and peptide 1 (DAEFRHDSGYE) was 55% and 69.4%, respectively. The ic-ELISA was applied to analyze Aβ1-42 in the urine and precipitated protein urine samples. This method can be used for detecting a normal level of total soluble Aβ (approximately 1 ng in 5 mg of precipitated urine protein) and can be used for detecting the early stages of AD. It is considered to be an easy and inexpensive method for monitoring and diagnosing AD.

This quasiexperimental study was designed to determine the effectiveness of a participatory program on pesticide use behavior and blood cholinesterase levels. The participants were 18–60 years old, living in Thung Satok subdistrict, San Pa Tong District, Chiang Mai Province. Eighty subjects, including 32 farmers and 48 consumers, were recruited to participate in the study voluntarily by a purposive sampling technique. Data concerning each individual’s behaviors were collected using questionnaires, and blood cholinesterase levels were obtained from whole blood finger, providing whole blood pre and postexperiment. The data were analyzed using Fishers’ exact and paired t-tests, for the problem situations were independently analyzed. The results show that the participatory process made it possible to improve methods for the prevention of the unhealthy effects of pesticides. After participating in the activities, both groups showed significantly higher scores in before and after knowledge ( P < 0.05 ) and a decrease in pesticide contamination in their bodies as a result of the measurement of average cholinesterase which increased significantly ( P < 0.001 ). In conclusion, the participatory program was applied to solve health problems from chemical hazards. The program can raise awareness about chemical toxicity, leading to the modification of the related behavior toward chemicals and reduction of the contamination of chemicals in the body. Therefore, the adoption of participatory processes can effectively solve problems related to chemical hazards that affect health.

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.