Honey as a bioindicator of environmental organochlorine insecticides contamination

Honey is a suitable matrix for the evaluation of environmental contaminants including organochlorine insecticides. The present study was conducted to evaluate residues of fifteen organochlorine insecticides in honey samples of unifloral and multifloral origins from Dir, Pakistan. Honey samples (5 g each) were extracted with GC grade organic solvents and then subjected to Rotary Evaporator till dryness. The extracts were then mixed with n-Hexane (5 ml) and purified through Column Chromatography. Purified extracts (1μl each) were processed through Gas Chromatograph coupled with Electron Capture Detector (GC-ECD) for identification and quantification of the insecticides. Of the 15 insecticides tested, 46.7% were detected while 53.3% were not detected in the honey samples. Heptachlor was the most prevalent insecticide with a mean level of 0.0018 mg/kg detected in 80% of the samples followed by β-HCH with a mean level of 0.0016 mg/kg detected in 71.4% of the honey samples. Honey samples from Acacia modesta Wall. were 100% positive for Heptachlor with a mean level of 0.0048 mg/kg followed by β-HCH with a mean level of 0.003 mg/kg and frequency of 83.3%. Minimum levels of the tested insecticides were detected in the unifloral honey from Ziziphus jujuba Mill. Methoxychlor, Endosulfan, Endrin and metabolites of DDT were not detected in the studied honey samples. Some of the tested insecticides are banned in Pakistan but are still detected in honey samples indicating their use in the study area. The detected levels of all insecticides were below the Maximum Residue Levels (MRLs) and safe for consumers. However, the levels detected can cause mortality in insect fauna. The use of banned insecticides is one of the main factors responsible for the declining populations of important insect pollinators including honeybees.

Association between pesticide exposure and obesity: A cross-sectional study of 20,295 farmers in Thailand

Background: Obesity is a serious condition because it is associated with other chronic diseases which affect the quality of life. In addition to diet and exercise, recent research has found that pesticide exposure might be another important risk factor. Methods: The objective of this large cross-sectional study was to determine the association between pesticide exposure and obesity among farmers in Nakhon Sawan and Phitsanulok province, Thailand. Data on pesticide use and obesity prevalence from 20,295 farmers aged 20 years and older was collected using an in-person interview questionnaire. The association was analysed using multivariable logistic regression, adjusted for its potential confounding factors. Results: Obesity was found to be associated with pesticide use in the past. The risk of obesity was significantly predicted by types of pesticides, including insecticides (OR = 2.27, 95% CI 1.09-4.74), herbicides (OR = 4.72, 95% CI 1.16-19.29), fungicides (OR = 2.17, 95% CI 1.37-3.44), rodenticides (OR = 2.52, 95% CI 1.59-3.99), and molluscicides (OR = 3.37, 95% CI 2.13-5.31). Among 35 surveyed individual pesticides, 24 were significantly associated with higher obesity prevalence (OR = 1.75, 95% CI 1.00-3.06 to OR = 8.37, 95% CI 3.97-17.64), including herbicide butachlor, 17 insecticides (three carbamate insecticides, five organochlorine insecticides, and nine organophosphate insecticides), and six fungicides. Conclusion: This study found obesity in farmers in Nakhon Sawan and Phitsanulok province, Thailand, to be associated with the long-term use of several types of pesticides. The issue should receive more public attention, and pesticide use should be strictly controlled.

Direct evidence of poison-driven widespread population decline in a wild vertebrate

Toxicants such as organochlorine insecticides, lead ammunition, and veterinary drugs have caused severe wildlife poisoning, pushing the populations of several apex species to the edge of extinction. These prime cases epitomize the serious threat that wildlife poisoning poses to biodiversity. Much of the evidence on population effects of wildlife poisoning rests on assessments conducted at an individual level, from which population-level effects are inferred. Contrastingly, we demonstrate a straightforward relationship between poison-induced individual mortality and population changes in the threatened red kite (Milvus milvus). By linking field data of 1,075 poisoned red kites to changes in occupancy and abundance across 274 sites (10 × 10-km squares) over a 20-y time frame, we show a clear relationship between red kite poisoning and the decline of its breeding population in Spain, including local extinctions. Our results further support the species listing as endangered, after a breeding population decline of 31% to 43% in two decades of this once-abundant raptor. Given that poisoning threatens the global populations of more than 2,600 animal species worldwide, a greater understanding of its population-level effects may aid biodiversity conservation through increased regulatory control of chemical substances. Our results illustrate the great potential of long-term and large-scale on-ground monitoring to assist in this task.

METHOD VALIDATION FOR ORGANOCHLORINE INSECTICIDES DETERMINATION IN GINSENG BY USING ISOTOPE-DILUTION GAS CHROMATOGRAPHY-MASS SPECTROMETRY (ID-GC-MS)

Organochlorine insecticides are still exploited among the most prominent pesticides for plant protection purposes. Known for having hazardous to humans and persistent in the environment properties, it is necessary to build an accurate method for detecting organochlorine insecticides in food and environmental substances. Isotope-dilution gas chromatography-mass spectrometry (ID-GC-MS) is a versatile coupling measurement system and high order method that combines both selectivity, sensitivity and high accuracy. The present paper aims at showing the methodology of the organochlorine insecticides (alpha-HCH and gamma-HCH) determination in ginseng by using ID-GC-MS. The described method covered sample preparation using an organic solvent (hexane) extraction, followed by florisil cleaning-up. After the reconstitution of the solvent base, the measurement was conducted by using ID-GC-MS in the optimal instrument parameter. Using the determined optimal conditions, the parameters such as sensitivity, linearity, precision, and accuracy were studied for validation of the ID-GC–MS method. The limit of detection and the limit of quantitation of the instrument were 0.5 ng/g and 2.0 ng/g for both analytes. The method showed linearity with the correlation coefficient of 0.999 for both alpha-HCH and gamma-HCH over the concentration range of 1‒300 ng/g. The precision ranged from 3.0 to 3.7% and 2.4 to 3.3% for alpha-HCH and gamma-HCH, respectively. The mean recoveries for alpha-HCH and gamma-HCH were found at 98.0 and 95.6%, respectively. Following method validation, the measurement uncertainty of the alpha-HCH and gamma-HCH determination was evaluated according to EURACHEM GUM guide at a 95 % confidence level (k = 2). The expanded uncertainty in the measurement of alpha-HCH and gamma-HCH was 5.4% and 8.2%, respectively. All these parameters demonstrate the high sensitivity of the offered method and the success of the described method in the determination of alpha-HCH and gamma-HCH in ginseng sample.

Geospatial distributions of organochlorine insecticide in shallot agriculture land at Wanasari sub-district, Brebes regency, Central Java, Indonesia

The organochlorine insecticide is a POPs compound that was monitored according to the Stockholm convention in 2003 because it can cause environmental damage and threaten human health. The study of the distribution of organochlorine insecticides on onion farms has been carried out in the village area in Wanasari sub-District and Brebes Regency. This study was conducted in March-June 2019, with the scope of soil sampling, organochlorine insecticide residue analysis, and spline interpolation. To determine the number of organochlorine insecticide residues using the SNI 06-6991.1-2004 method, while to determine the distribution pattern using the Spline interpolation method with the ArcGIS 10.4. In preparing geospatial residues, we use the ratio of the maximum residual limit (MRLs) of each organochlorine active ingredient. These research sites can be categorized as severe pollution of OCPs insecticides. In this study OCPs residues (Aldrin, Lindane, and Heptachlor, DDT, Endrin, and Dieldrin) can be found with concentrations above the MRLs requirements. OCPs residues with very high range characteristics are shown by Aldrin, DDT, Endrin, and Dieldrin each of more than 50% of the total observed land area. Point numbers six detected all OCPs residues were observed with concentrations exceeding MRLs.