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The article offers news briefs related to pesticide research. Topics discussed include approval for approval granted by the California Department of Pesticide Regulation (CDPR), United Phosphorus Ltd. benefits from the China-U.S. trade war and IPCC2019 on the theme "Crop Protection to outsmart Climate Change for Food Security & Environmental Conservation" organized by the International Crops Research Institute for the Semi-arid Tropics (ICRISAT).

This article examines the rise of the Centers for Disease Control and Prevention's (CDC's) small but influential program on the human toxicology of synthetic pesticides after World War II. For nearly 20 years, scientists working in the CDC's Toxicology Section conducted a range of laboratory, field, and clinical studies to assess whether pesticides, such as dichlorodiphenyltrichloroethane (DDT), caused harm to humans. Applying an industrial hygiene approach to study pesticide toxicity, the team used the symptoms of poisoning as their criteria for harm and consistently found that, when used as intended, pesticides were generally safe for humans. In the post– Silent Spring era, these findings were increasingly challenged as the field of toxicology developed and different ways of understanding pesticide toxicity gained greater acceptance. While it is easy to dismiss the CDC's findings as excessively narrow, examining how the team arrived at their conclusions provides an instructive lesson about the powerful ways conceptual frameworks shape scientific inquiry and the unexpected ways data can be reinterpreted in different problem contexts. (Am J Public Health. 2019;109:1548–1556. doi: 10.2105/AJPH.2019.305260) [ABSTRACT FROM AUTHOR]

Management of pesticide standard values (PSVs) in different human exposure pathways is critical since pesticides may significantly impact human health from the exposure. Aldicarb, Atrazine, Diuron, Glyphosate, and MCPA are the five most widely used pesticides in the world. Many international jurisdictions have been working on regulating PSVs for these five pesticides. However, there is little agreement on PSVs among regulatory jurisdictions so far and most nations developed their PSVs without considering all the major exposure pathways. To make the PSVs more efficient in the protection of human health, theoretical maximum daily intake (TMDI) was introduced in this research to convert the PSVs into maximum mass loadings and evaluate the PSVs in a more comprehensive way. The computed TMDIs of these five pesticides vary from 4.45 to 6.75 orders of magnitude. For example, some nations only regulated the MCPA in one or two major exposures, and there are 87 computed TMDI values of MCPA (69.1% of the total) higher than the acceptable daily intake value of MCPA, indicating that those PSVs from major exposure pathways are not conservative enough in terms of protecting human health. Unless the TMDI values are computed based on the PSVs from all major exposure pathways, they might not be sufficient to protect human health from additional exposures. [ABSTRACT FROM AUTHOR]

There is increasing concern that standard laboratory toxicity tests may be misleading when assessing the impact of toxicants, because they lack ecological realism. Both warming and biotic interactions have been identified to magnify the effects of toxicants. Moreover, while biotic interactions may change the impact of toxicants, toxicants may also change the impact of biotic interactions. However, studies looking at the impact of biotic interactions on the toxicity of pesticides and vice versa under warming are very scarce. Therefore, we tested how warming (+4 °C), intraspecific competition (density treatment) and exposure to the pesticide chlorpyrifos, both in isolation and in combination, affected mortality, cannibalism, growth and heat tolerance of low- and high-latitude populations of the damselfly Ischnura elegans . Moreover, we addressed whether toxicant exposure, potentially in interaction with competition and warming, increased the frequency of autotomy, a widespread antipredator mechanism. Competition increased the toxicity of chlorpyrifos and made it become lethal. Cannibalism was not affected by chlorpyrifos but increased at high density and under warming. Chlorpyrifos reduced heat tolerance but only when competition was high. This is the first demonstration that a biotic interaction can be a major determinant of ‘toxicant-induced climate change sensitivity’. Competition enhanced the impact of chlorpyrifos under warming for high-latitude larvae, leading to an increase in autotomy which reduces fitness in the long term. This points to a novel pathway how transient pesticide pulses may cause delayed effects on populations in a warming world. Our results highlight that the interplay between biotic interactions and toxicants have a strong relevance for ecological risk assessment in a warming polluted world. [ABSTRACT FROM AUTHOR]

The main organic pollutants worldwide are pesticides, persistent chemicals that are of concern owing to their prevalence in various ecosystems. In nature, pesticide remainders are subjected to the chemical, physical, and biochemical degradation process, but because of its elevated stability and some cases water solubility, the pesticide residues persist in the ecosystem. The removal of pesticides has been performed through several techniques classified under biological, chemical, physical, and physicochemical process of remediation from different types of matrices, such as water and soil. This review provides a description of older and newer techniques and materials developed to remove specific pesticides according to previous classification, which range from bioremediation with microorganisms, clay, activated carbon, and polymer materials to chemical treatment based on oxidation processes. Some types of pesticides that have been removed successfully to large and small scale include, organophosphorus, carbamates, organochlorines, chlorophenols, and synthetic pyrethroids, among others. The most important characteristics, advantages, and disadvantages of techniques and materials for removing pesticides are described in this work. [ABSTRACT FROM AUTHOR]

It has been shown for the first time that aqueous solutions of metaphos pesticide (1×10-1×10 mol/L) are disperse systems, the disperse phase undergoing rearrangement upon dilution. The relationship between nonmonotonic concentration dependences of the nanoassociate size, physico-chemical properties of the systems, and their action on higher plants and hydrocoles has been found. [ABSTRACT FROM AUTHOR]

An electrochemical method based on non-enzymatic inhibition for the determination of organophosphorus pesticide (OPPs) using pralidoxime chloride (PAM-Cl) as a universal electrochemical probe was reported. Cyclic voltammetry was performed to characterize the redox properties of pralidoxime and OPPs. Differential pulse voltammetry (DPV) was carried out to analyze the influence of anion (chloride and iodide ions), to optimize the pH of testing condition, and to explore the relationship between pralidoxime and OPPs. The results showed that iodide ion generated an anodic peak close to the peak of pralidoxime, which would interfere in the detection of OPPs. Phosphate buffer solution (pH 7.0) was chosen because of its high peak current and low peak potential when testing PAM-Cl by DPV. Chlorpyrifos, fenthion, and methyl parathion were examples of three existing OPPs detection methods. The peak current of PAM-Cl decreased along with the increase of concentration of OPPs in the solution. The limit of detection was 0.018 μM, 0.100 μM, and 0.215 μM, respectively. It was the first time for PAM-Cl to be used as a universal electrochemical probe to develop a simple, cheap and stable method for OPPs detection. [ABSTRACT FROM AUTHOR]

The objective of this study is to perform a safety assessment of chromafenozide residue level on tomato at the Egyptian national level. An open field decline study of chromafenozide on tomato was performed. The theoretical maximum daily intake (TMDI) of chromafenozide was calculated for assessing the chronic dietary exposure indicating that the ADI value of chromafenozide (0.27 mg/kg bw/day) was not exceeded. As a result, the safety assessment of chromafenozide residue levels was attained. A validated method of the QuEChERS approach followed by HPLC-DAD analysis was used to determine the chromafenozide residues. The recoveries ranged from 70 to 88% with relative standard deviations ranging from 2.0 to 9.0%. The limit of quantitation was 0.01 mg/kg. The half-life of chromafenozide on tomatoes was 3.5 days. [ABSTRACT FROM AUTHOR]

In vitro toxic effects of selected pesticides (cypermethrin, flumethrin, propoxur, carbaryl, chlorpyrifos, metamidophos) were evaluated on dog and buck fresh spermatozoa using MTT (mitochondrial activity/viability), NeutralRed-NR (lysosomal activity/viability) and CASA (motility parameters/VCL, VSL, VAP, linearity, straightness, wobble) tests. For buck, the most toxic compounds were carbamates followed by organophosphate and pyrethroids. Carbamates, again induced the highest toxicity in dog sperm, followed by pyrethroids. In general, all pesticide treatments were found to increase the hyperactivity of buck spermatozoa except flumethrin; whereas a decrease was present for dog spermatozoa (except carbaryl). A decrease of VCL, VSL and VAP parameters was evident in buck (P<0.05), whereas no difference was found in dog sperm (P>0.05). Overall, flumethrin was found to induce less effect on motility parameters compared to cypermethrin. As a conclusion, the combination of MTT and CASA along with NR would provide more accurate data for the in vitro evaluation of chemicals on spermatozoa; where alternative testing strategies for the ReproTox tests (especially for cosmetic product safety assessment where animal testing is banned) are recommended nowadays with battery strategies and species specific differences would play a key role for understanding the defense mechanisms. [ABSTRACT FROM AUTHOR]

Pesticide exposure has been associated with different adverse health effects which may be modulated to some extent by paraoxonase-1 (PON1) activity and genetic polymorphisms. This study assessed seasonal variations in PON1 activity (using paraoxon –POase–, phenylacetate –AREase–, diazoxon –DZOase– and dihydrocoumarin –DHCase– as substrates), erythrocyte acetylcholinesterase (AChE) and plasma cholinesterase (using butyrylthiocholine –BuChE– and benzoylcholine –BeChE– as substrates. The study population consisted of intensive agriculture workers regularly exposed to pesticides other than organophosphates and non-exposed controls from Almería (Southeastern Spain). The effect of common genetic polymorphisms of PON1 and BCHE on paraoxonase-1 and cholinesterase activities toward different substrates was also assessed. Linear mixed models were used to compare esterase activities in agricultural workers and control subjects over the two study periods (high and low exposure to pesticides). The significant decrease in AChE and increase in BuChE and BeChE activities observed in workers with respect to control subjects was attributed to pesticide exposure. Workers also had higher levels of AREase, DZOase and, to a lesser extent, of POase, but showed decreased DHCase activity. While PON1 Q192R and PON1 -108C/T gene polymorphisms were significantly associated with all PON1 activities, PON1 L55M showed a significant association with AREase, DZOase and DHCase. BCHE-K (Karlow variant) was significantly associated with lower BeChE activity (but not with BuChE) and BCHE-A (atypical variant) showed no significant association with any cholinesterase activity. These findings suggest that increased PON1, BuChE and BeChE activities in exposed workers might result from an adaptive response against pesticide exposure to compensate for adverse effects at the biochemical level. This response appears to be modulated by PON1 and BCHE gene polymorphisms. [ABSTRACT FROM AUTHOR]

A simple and sensitive analytical method based on QuEChERS approach using liquid chromatography tandem mass spectrometry was developed and validated for the determination of 6-benzylaminopurine, carbendazim and thiabendazole in bean sprouts. Sodium chloride and sodium acetate were used for salting-out step and magnesium sulfate for clean-up. The validation of optimized method was satisfactory with recoveries, between 89.5% and 103.2% for the three compounds, and relative standard deviation (RSD) values less than 3.3% at 20 and 40 ng/g fortification levels (n = 5). Limit of detection (LOD) and limit of quantification (LOQ) was 2.1–3.7 ng/g and 6.3–11.1 ng/g, respectively. Monitoring of 126 bean sprout samples collected from local markets was performed to verify the adaptability in real samples. No pesticides were detected but 6-benzylaminopurine was found in 3 samples at the level of 15–20 ng/g. The optimized method should be applicable for monitoring of 6-benzylaminopurine, carbendazim and thiabendazole in bean sprouts in short time. [ABSTRACT FROM AUTHOR]

The peppers were grown using either pesticide-free or conventional production systems and stored at 8 °C in one of four storage methods, i.e. regular atmosphere (control), cling film (CF), modified atmosphere packaging (MAP) or a proprietary controlled atmosphere (CA) storage system (Palliflex™, PL) of 2 kPa O 2 + 3 kPa CO 2 . Internal atmospheres created by the MAP were periodically assessed during storage, and O 2 and CO 2 levels in both pecticide-free and conventionally-grown peppers were suitably maintained within recommended limits, 3–5 kPa O 2 + 2–8 kPa CO 2 . Weight loss of peppers stored in PL was lower (<4% at 45 d) than for other treatments in both production systems. After 45 d of storage, peppers stored in PL and control had higher total soluble solids content compared with the CF and MAP treatments in the conventional production system. Titratable acidity and total phenolics content first increased then decreased in all treatments. The contents of ascorbic acid in both pesticide-free and conventionally-grown peppers declined, and β-carotene content increased progressively with storage time. In terms of the production systems, the lowest weight loss and total soluble solids contents were in the pesticide-free production system. Furthermore, the pesticide-free production system had higher titratable acidity, total phenolics and ascorbic acid contents, compared with the conventional production system. The lowest decay incidence was in the conventional production system. In conclusion, the pesticide-free production system could be an alternative production system for pepper growing and PL storage could be used to maintain postharvest quality attributes of peppers up to 45 d both in pesticide-free and conventionally-grown peppers. [ABSTRACT FROM AUTHOR]

The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State, Ireland, and co-rapporteur Member State, Belgium, for the pesticide active substance silthiofam are reported. The context of the peer review was that required by Commission Implementing Regulation ( EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative use of silthiofam as a fungicide (seed treatment) on cereals (wheat, barley, triticale, spelt). The reliable end points, appropriate for use in regulatory risk assessment are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified. [ABSTRACT FROM AUTHOR]

The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State, Spain, and co-rapporteur Member State, France, for the pesticide active substance flazasulfuron are reported. The context of the peer review was that required by Commission Implementing Regulation ( EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative uses of flazasulfuron as a herbicide on vineyards, citrus and olive orchards. The reliable end points, appropriate for use in regulatory risk assessment, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified. [ABSTRACT FROM AUTHOR]

An ultrasensitive method for the simultaneous analysis of pesticides residues in tobacco was developed with online size exclusion chromatography with gas chromatography and tandem mass spectrometry. Tobacco samples were extracted with the solvent mixture of cyclohexane and acetone (7:3, v/v) and centrifuged. Then, the supernatant liquors were injected directly into the online size exclusion chromatography with gas chromatography and tandem mass spectrometry without any other purification procedures after being filtered with a 0.22 μm organic phase filter. The matrix interferences were effectively removed and recoveries of most pesticides were in the range of 72-121%. Especially, for chlorothalonil, the analysis efficiency of this method was much more favorable than that of the general method, in which dispersive solid-phase extraction was used as an additional purified procedure. In addition, the limits of quantitation of this method were from 1 to 50 μg/kg. Therefore, a rapid, cost-effective, labor-saving method was proposed in the present work, which was suitable for the analysis of 41 pesticide residues in tobacco. [ABSTRACT FROM AUTHOR]

A simple, rapid, and efficient ultrasound-assisted emulsification microextraction method followed by gas chromatography mass spectrometry in selected ion monitoring mode was developed for the determination of organochlorine pesticides in honey samples. The type and volume of organic extraction solvent, pH, effect of added salt content, and centrifuging time and speed were investigated. Under the optimum extraction conditions, 30 μL of 1, 2-dibromoethane (extraction solvent) was immersed into an ultrasonic bath for 1 min at 40°C. The limits of detection and quantification for all target pesticides were 0.003-0.06 and 0.01-0.2 ng/g, respectively. The extraction recovery was 91-100% and the enrichment factors were 168-192. The relative standard deviation for the method was <6% for intraday ( n = 6) and <8% for interday precision ( n = 4). The proposed method was successfully applied for the analysis of organochlorine pesticides in honey samples. [ABSTRACT FROM AUTHOR]

This paper describes the development of a method for the determination of six pesticides (tebuthiuron, carbofuran, atrazine, metribuzine, ametryn, and bifenthrin) in sugarcane juice using microextraction by packed sorbent as the extraction technique. The extraction steps were optimized by factorial design, being the variables pH, ionic strength, desorption solvent and solvent volume optimized for comparisons among sorbent materials. Among the evaluated materials C18-Chromabond ® showed better extraction efficiency. A factorial design 23 with central point was used for the extraction cycles optimization. Draw/eject and washes cycles showed significant improvements in the extraction efficiency when the number of cycles increased. The method was validated and showed a limit of quantification in the range of 2.0-10.0 μg.L−1. The calibration curves were constructed by weighting models that reduced the sum of absolute residues values and improved determination coefficient. The matrix factor and extraction efficiency were 97.3-77.3% and 27.1-64.8%, respectively. The accuracy was 71.7-106.9%; precision evaluated as the coefficient of variance obtained in intra and inter day analysis was 4.5-15.9%. The method was applied to the determination of pesticide residues in four sugarcane juice samples commercially available in markets from different cities from São Paulo state, Brazil. [ABSTRACT FROM AUTHOR]

Compared to other organophosphate-resistant and -susceptible (S) lines of Bactrocera dorsalis , the carboxylesterase (CBE) Bd E5 in the naled-resistant (nal-r) line has been found to possess remarkable quantitative elevation. Our study attempts to identify the role of Bd E5 in naled resistance, and we discovered several points of interest. Firstly, activity staining on native PAGE revealed that the percentage of flies with intensive Bd E5 bands in the nal-r line was substantially higher than in the S line, indicating that the Bd E5 band correlates with naled susceptibility. Secondly, in vitro and in vivo inhibition assays showed that Bd E5 was inhibited by naled in both lines; under diagnostic doses of naled, the overall extent of inhibition on CBEs was much greater in the S line than in the nal-r line. Thirdly, NanoLC-nanoESi-MS/MS analysis used the NCBI database to identify and annotate Bd E5 as an esterase FE4-like (XP_011200445.1) in B. dorsalis . Fourthly, rapid amplification of cDNA ends was used to obtain the 2012-bp full-length Bd E5 cDNA, which contained an open reading frame of 1770 bp and encoded a putative protein of 590 amino acid residues. Phylogenetic analysis revealed that Bd E5 is a secreted β-esterase (E clade) closely related to CG6414 (NP_570089), a CBE in Drosophila melanogaster . Finally, our relative quantification real-time PCR data showed a significant elevation in transcript levels of the Bd E5 gene in nal-r line. Our results confirmed that Bd E5 is correlated with naled resistance and provides further understanding about the identification and molecular characteristics of Bd E5 in B. dorsalis . [ABSTRACT FROM AUTHOR]

ABSTRACT The freshwater Anacostia River watershed (Maryland, DC, USA) was surveyed for the sources of bioavailable US Environmental Protection Agency (USEPA) Priority Pollutants and toxic metals by active biomontoring (ABM) using the freshwater Asiatic clam Corbicula fluminea. The Anacostia River is a 456 km2 tributary of the tidal freshwater Potomac River that includes the city of Washington, DC where edible fish are highly contaminated with PCBs and chlordane. From 1999 to 2011, Corbicula were collected for ABM from a Potomac reference site and translocated in cages placed at 45 sites in the tidal and nontidal Anacostia watershed. Minimum clam mortality and maximum contaminant bioaccumulation was with 2-week translocation. The clam tissues (28-50) were combined at sites and analyzed by TestAmerica for 66 USEPA Priority Pollutants plus technical chlordane, benz(e) pyrene, and 6 metals (As, Cd, Cr, Cu, Fe, Pb). Tissue contaminants reflected water, not sediment, levels. To compare sites, all contaminant data above detection or reference were grouped as total metals (TMET), total polycyclic aromatic hydrocarbons (TPAH), total PCB congeners (TPCB), total pesticides (TPEST), and total technical chlordane (TCHL). Tidal Anacostia ABM found highest TPAH and TCHL upstream at Bladensburg Marina (MD) except for TCHL at site PP near the confluence. Five nontidal MD subtributaries (94% of flow) had 17 sites with bioavailable TPAH, TPCB, or TCHL 2 to 3 times higher than found at the toxic-sediment 'hotspots' near Washington. The only TMET noted was Fe at 1 site. TPAH in MD subtributaries was highest near industrial parks and Metro stations. A naphthalene spill was detected in Watts Branch. TPCB (low molecular weight) originated upstream at 1 industrial park. Total technical chlordane (80% of TPEST) was 2 to 5 times the US Food and Drug Administration action in 4 nontidal tributaries where heptachlor indicated legacy chlordane dumpsites. Total technical chlordane fell to reference below a stormwater pond, suggesting transport via suspended sediment. Controlling the formation and movement of contaminated TSS in MD should enable the uncontaminated-sediment capping of Washington DC's toxic-sediment 'hot-spots' that are presently considered responsible for fish contamination. Integr Environ Assess Manag 2016;12:548-558. © 2015 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Pesticide transport by surface runoff depends on climate, agricultural practices, topography, soil characteristics, crop type, and pest phenology. To accurately assess the impact of climate change, these factors must be accounted for in a single framework by integrating their interaction and uncertainty. This article presents the development and application of a framework to assess the impact of climate change on pesticide transport by surface runoff in southern Québec (Canada) for the 1981-2040 period. The crop enemies investigated were: weeds for corn ( Zea mays); and for apple orchard ( Malus pumila), 3 insect pests (codling moth [ Cydia pomonella], plum curculio [ Conotrachelus nenuphar], and apple maggot [ Rhagoletis pomonella]), 2 diseases (apple scab [ Venturia inaequalis], and fire blight [ Erwinia amylovora]). A total of 23 climate simulations, 19 sites, and 11 active ingredients were considered. The relationship between climate and phenology was accounted for by bioclimatic models of the Computer Centre for Agricultural Pest Forecasting (CIPRA) software. Exported loads of pesticides were evaluated at the edge-of-field scale using the Pesticide Root Zone Model (PRZM), simulating both hydrology and chemical transport. A stochastic model was developed to account for PRZM parameter uncertainty. Results of this study indicate that for the 2011-2040 period, application dates would be advanced from 3 to 7 days on average with respect to the 1981-2010 period. However, the impact of climate change on maximum daily rainfall during the application window is not statistically significant, mainly due to the high variability of extreme rainfall events. Hence, for the studied sites and crop enemies considered, climate change impact on pesticide transported in surface runoff is not statistically significant throughout the 2011-2040 period. Integr Environ Assess Managem 2016;12:559-571. © Her Majesty the Queen in Right of Canada 2015; Published 2015 SETAC [ABSTRACT FROM AUTHOR]

The predator Chrysoperla carnea is a model species for the study of non-target effects of pesticides under different scenarios: registration of plant protection products under the European Union and effects of the Bt toxin. Laboratory and persistence studies were carried out with six pesticides currently used in corn crops in Spain that were applied at their maximum field recommended concentrations. The assessed end-points were larval mortality, survivorship until adult stage, duration of the larval and pupal periods, fecundity, fertility and sex ratio of the emerged adults. Based on the total effect (lethal and sublethal) caused to L larvae in contact with fresh residues in the laboratory, pendimethalin was harmless (IOBC 1), lambda-cyhalothrin, abamectin, and hexythiazox were slightly harmful (IOBC 2), deltamethrin was moderately harmful (IOBC 3) and chlorpyrifos was harmful (IOBC 4). Afterwards, the residues of the two most toxic pesticides in the lab (deltamethrin and chlorpyrifos) were aged under greenhouse conditions (22 ± 2 °C, 40 ± 10 % R.H., 16.9 μmol m s UV radiation) in the presence and absence of artificial rainfall (10 l m h, applied 24 h after pesticide application). Deltamethrin was classified as short lived (IOBC A) in both cases. However, degradation of chlorpyrifos residues was accelerated in the presence of rainfall, leading to the classification as slightly persistent (IOBC B), while in absence of rainfall it behaved as persistent (IOBC D). Every pesticide can be recommended for inclusion in corn IPM programs where the predator is present except chlorpyrifos that exhibited high direct toxicity in the lab and prolonged residual action even in the presence of rainfall. [ABSTRACT FROM AUTHOR]

Acetylcholinesterase (AChE) biosensor based on conducting poly([2,2̍ʹ;5̍′ 2″]-terthiophene-3̍-carbaldehyde) (PTT) modified glassy carbon electrode (GCE) was constructed. AChE was immobilized on PTT film surface through the covalent bond between aldehyde and amino groups. The properties of PTT modified GCE were studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The biosensor showed an oxidation peak at +0.83 V related to the oxidation of thiocholine, hydrolysis product of acetylthiocholine iodide (ATCI), catalyzed by AChE. The optimum current response of the biosensor was observed at pH 7.5-8.0, 40 °C and 120 U/cm of AChE concentration. The biosensor showed a high sensitivity (183.19 μA/mM), a linear range from 0.015 to 1.644 mM, and a good reproducibility with 1.7 % of relative standard deviation (RSD). The biosensor showed a good stability. The interference of glycin, ascorbic acid, histidine, uric acid, dopamine, and arginine on the biosensor response was studied. An important analytical response from these inteferents that overlaps the biosensor response was not observed. The inhibition rate of malathion as a model pesticide was proportional to its concentrations from 9.99 to 99.01 nM. The detection limit was 4.08 nM. [ABSTRACT FROM AUTHOR]

Research using low-density polyethylene (LDPE) passive samplers has steadily increased over the past two decades. However, such research efforts remain hampered because of strict guidelines, requiring that these samplers be quickly transported in airtight metal or glass containers or foil wrapped on ice. We investigate the transport stability of model pesticides and polycyclic aromatic hydrocarbons (PAHs) with varying physicochemical properties using polytetrafluoroethylene (PTFE) bags instead. Transport scenarios were simulated with transport times up to 14 days with temperatures ranging between −20 and 35 °C. Our findings show that concentrations of all model compounds examined were stable for all transport conditions tested, with mean recoveries ranging from 88 to 113 %. Furthermore, PTFE bags proved beneficial as reusable, lightweight, low-volume, low-cost alternatives to conventional containers. This documentation of stability will allow for more flexible transportation of LDPE passive samplers in an expanding range of research applications while maintaining experimental rigor. [ABSTRACT FROM AUTHOR]

BACKGROUND The Pesticide Concentration in a Paddy Field model ( PCPF-1) was modified by adding a root zone compartment to simulate nursery-box-applied ( NB-applied) pesticide. The PCPF-NB model was validated for predicting the concentrations of NB-applied fipronil and imidacloprid in rice paddy fields using two treatment methods: before transplanting ( BT) and at sowing ( AS). Uncertainty and sensitivity analyses were used to evaluate the robustness of the concentrations predicted by the model. RESULTS The hourly predicted concentrations of imidacloprid and fipronil were accurate in both paddy water and 1 cm deep paddy soil. The coefficient of determination and Nash-Sutcliffe model efficiency were greater than 0.87 and 0.60 respectively. The 95th percentiles of the predicted concentrations of fipronil and imidacloprid indicated that the influence of input uncertainty was minor in paddy water but important in paddy soil. The pesticide deposition rate and the desorption rate from the root zone were identified to be the major contributors to the variation in the predicted concentrations in paddy water and soil. CONCLUSION The PCPF-NB model was validated for predicting the fate and transport of NB-applied fipronil and imidacloprid using the BT and AS treatment methods. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND In the agricultural sector, toxic substances can be released into the atmosphere. In recent years, Europe has encountered a significant environmental issue related to the dispersion of pesticides during maize seeding, especially when performed with pneumatic seed drills. This phenomenon can be very dangerous for insects, as the dispersed dust contains pesticides (insecticides, fungicides, etc.) used to dress maize seeds. On the basis of these considerations, experimental tests have been carried out using a filtration system to clean the airflow that exits from the fan of pneumatic maize seed drills. RESULTS The tested filtration system does not interfere with the seeding quality because the vacuum level observed within the filtration system assembled on the seeder (5.7 kPa) is 27% higher than the correct vacuum level to guarantee good seeding quality (4.2 kPa). In addition, it enables a reduction in the risk of environmental contamination, as no dust deposits were found at different distances from the machine. CONCLUSION The use of a filtration system shows advantages in terms of environmental and operator safety because dangerous materials are contained in the filter case, thus avoiding contamination of neighbouring areas and the machinery used (tractor and seed drill). © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In the context of the mandated phaseout of methyl bromide, California’s strawberry industry has increased its use of chloropicrin, another soil fumigant that has long been on the market. However, due to its 2010 designation as a toxic air contaminant, the US Environmental Protection Agency and California’s Department of Pesticide Regulation have developed enhanced application protocols to mitigate exposures of the chemical to bystanders, nearby residents, and farmworkers. The central feature of these mitigation technologies are enhanced buffer zones between treated fields and nearby buildings. Not only do buffer zones inherently privilege neighbors over farmworkers, but the determinations of the size of these buffer zones are also based on acceptable threshold levels and probabilities that allow significant exposures to those they are designed to protect. Moreover, these protocols require human monitors to detect sensory irritation. While the science and technology studies literature is highly useful for understanding the inextricability of science and politics in developing protective measures and is attentive to what counts as data in setting acceptable thresholds, it tends to overlook that social sorting is intrinsic to such regulation. We thus turn to Foucault’s biopolitics to make sense of regulations that are designed to protect but inherently allow some to become ill. Doing so illuminates how determinations of the bright line are at once technical–political as well as implicit decisions about whose bodies count. [ABSTRACT FROM AUTHOR]

Enantiomeric separation of six chiral pesticides by high-performance with permethylated &#x03B2;-cyclodextrin (&#x03B2;-PM) chiral stationary phase were tested under conditions. The influences of water composition from 10% to 45% in the mobile phase and column temperatures from 0&#x00B0;C to 40&#x00B0;C on the separation were investigated. Chromatographic parameters including selectivity factors (&#x03B1;), factors (k), and resolution factors (Rs) were selected to evaluate the separation efficiency in different conditions. Baseline separation was obtained for diclofop-methyl, fenoxaprop-ethyl, tebuconazole, and triticonazole, and Rs of these pesticides were greater than 1.5. However, etoxazole and lactofen were partially separated in all experiments. The parameters of &#x03B1; and k were decreased by the increasing temperature for all investigated pesticides, but the best resolution for etoxazole (Rs = 0.94) and lactofen (Rs = 0.59) was achieved at 20&#x00B0;C, different from the Rs tendency of other pesticides, which decreased with a temperature increase. Chirality 28:409-414, 2016. &#x00A9; 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the adsorption of non-polar (tebuconazole, triadimenol) and polar (cymoxanil, pirimicarb) pesticides by soils after applying the biosorbent spent mushroom substrate (SMS) at different rates. The adsorption isotherms of pesticides by three soils and SMS-amended soils were obtained and the adsorption constants were calculated. The distribution coefficients ( K) increased 1.40-23.1 times (tebuconazole), 1.08-23.7 times (triadimenol), 1.31-42.1 times (cymoxanil), and 0.55-23.8 times (pirimicarb) for soils amended with biosorbent at rates between 2 and 75 %. Increasing the SMS rates led to a constant increase in adsorption efficiency for non-polar pesticides but not for polar pesticides, due to the increase in the organic carbon (OC) content of soils as indicated by K values. The OC content of SMS-amended soils accounted for more than 90 % of the adsorption variability of non-polar pesticides, but it accounted for only 56.3 % for polar pesticides. The estimated adsorption of SMS-amended soils determined from the individual adsorption of soils and SMS was more consistent with real experimental values for non-polar pesticides than for polar pesticides. The results revealed the use of SMS as a tool to optimize pesticide adsorption by soils in dealing with specific contamination problems involving these compounds. [ABSTRACT FROM AUTHOR]

Background: The hazards of pesticide exposure have been a growing concern globally. The increase of susceptibility of farmers to pesticide intoxication is due to lack of knowledge regarding safe and proper pesticide handling. The aim of this study was to evaluate cocoa farmers' pesticide exposure by assessing the ways in which they store pesticides, operational habits exhibited during and after pesticide application and the use of personal protective equipment (PPE) during pesticide application in the Brong Ahafo Region of Ghana. Methods: Two hundred and forty (240) cocoa farmers were randomly selected and interviewed using a structured questionnaire. Results: Majority of the farmers were aware of the negative effects of pesticides on their health and the environment if not well handled. Despite the awareness, most farmers did not handle pesticides with care and do not adhere to the use of PPE, hence, increasing their risks to danger of exposure to pesticides. Storage of pesticides in bedrooms was reported by 22.5 % of farmers; an indication of a high risk of pesticides exposure through direct inhalation. Cocoa farmers' in the study area exhibited operational habits such as eating, drinking water and alcohol, smoking cigarette and tobacco pipes, chewing gum and sticks, talking, using the mouth to remove blockages from sprayer nozzles, stirring pesticides with bare hands, among others during pesticides application. The survey revealed that only 35 % of farmers put on full PPE while 45 % put on partial PPE [which is any or combination of the following; cap/hat, respirator, goggle, rubber glove, overall and wellington boot (rubber boot)] during pesticides application. On the other hand, 20 % of farmers in the study area applied pesticides without wearing PPE. These practices expose farmers to adverse health risks. Factors that influenced farmers' decision to use PPE included farming experience, age of farmer, access to extension service, availability of a chemical shop, farm size and educational level. Conclusion: The results indicate high risks of exposure of cocoa farmers in the study area to toxicity and health hazards of pesticides due to mishandling and habits exhibited during pesticide application. There is a need to improve habits of safe use and handling of pesticides among farmers through education and training. There is also a need for education on the use of PPE during pesticides application to avoid exposure and health hazards. [ABSTRACT FROM AUTHOR]

The rapid increase of the prevalence of autism spectrum disorder (ASD) suggests that exposure to chemicals may impact the development of ASD. Therefore, we reviewed literature on the following chemicals, nutrient to investigate their association with ASD: (1) smoke/tobacco, (2) alcohol, (3) air pollution, (4) pesticides, (5) endocrine-disrupting chemicals, (6) heavy metals, (7) micronutrients, (8) fatty acid, and (9) parental obesity as a proxy of accumulation of specific chemicals or nutritional status. Several chemical exposures such as air pollution (e.g., particular matter 2.5), pesticides, bisphenol A, phthalates, mercury, and nutrition deficiency such as folic acid, vitamin D, or fatty acid may possibly be associated with an increased risk of ASD, whereas other traditional risk factors such as smoking/tobacco, alcohol, or polychlorinated biphenyls are less likely to be associated with ASD. Further research is needed to accumulate evidence on the association between chemical exposure and nutrient deficiencies and ASD in various doses and populations. [ABSTRACT FROM AUTHOR]

Background & Aims Geoepidemiological data of hepatocellular carcinoma ( HCC) are lacking. Crete has a genetically homogeneous population and is suitable for studies to identify a possible contribution of environmental factors in HCC. Methods Databases for HCC (316 cases), hepatitis B virus ( HBV) (633) and hepatitis C virus ( HCV) (392), constructed over the past 20 years in our Unit, were used. Data included place of birth and place of residence for the last 15 years. Hellenic Statistical Authority provided population statistics from 1980 to 2014. Time-spatial methods were applied in Gis-ArcMap 10 software. Spatial autocorrelation tests (Moran's index) detected differences between the spatial distribution to place of residence. Spatial density maps were created. Kriging Interpolation was applied, to produce prediction maps of HCC. Results Hepatitis C virus appears in areas of high prevalence while HBV is uniformly distributed. HCC is more prevalent in Eastern Crete. A spatial autocorrelation between HCC and either HCV (Moran's I = 0.88, P < 0.001) or HBV (I = 0.84, P < 0.02) was found as expected. However, there is a discrepancy in the South East of Crete, where a higher prevalence of HCC than expected was observed. This is an area where extensive use of pesticides in large green houses is practiced. Conclusions Hepatocellular carcinoma is associated with the dispersion of HCV and HBVs. In an area with widespread use of pesticides, a higher than expected spatial distribution of HCC was detected. [ABSTRACT FROM AUTHOR]

Background: Deltamethrin (DLM) is a broad-spectrum synthetic dibromo-pyrethroid pesticide that is widely used for agricultural and veterinary purposes. However, human exposure to the pesticide leads to neurotoxicity. Glutamine is one of the principal, free intracellular amino acids and may also be an antioxidant. This study was undertaken in order to examine the neuroprotective and antioxidant potential of L-glutamine against DLM toxicity in female Wistar albino rats. Materials and methods: The rats were divided into the following groups (n=10): Group I: control (distilled water; 10 mL/kg, po one dose), Group II: L-glutamine (1.5 g/kg, po one dose), Group III: DLM (35 mg/kg, po one dose), and Group IV: DLM (35 mg/kg, po one dose) and L-glutamine (1.5 g/kg, po one dose after 4 hours). Total oxidant status (TOS), total antioxidant status (TAS), tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 levels and apoptosis were evaluated in brain tissue. Results: DLM-treated animals had a significant increase in brain biochemical parameters, as well as TOS and TAS. Furthermore, the histopathological examination showed neuronal cell degeneration in the cerebral tissue. L-Glutamine treatment decreased the elevated brain levels of TOS and neuronal cell degeneration. There was no difference in tumor necrosis factor-α, IL-1β, and IL-6 levels between the groups. Conclusion: L-Glutamine may reduce the toxic effects of DLM in the cerebral tissue through antioxidant properties. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to assess cost dominance in direct inputs between arable crop-based systems using low or high pesticide levels per hectare. Our investigation departs from a traditional efficiency analysis and aims at comparing two minimal direct cost functions excluding pesticide expenses. This means that we evaluate the gap between two efficient frontiers instead of focusing on individual farm inefficiency scores. Our only objective is to compare two optimal cost benchmarks for systems respectively defined with high or low pesticide levels per hectare by varying their scale and output mix. A robust approach frontier is introduced to control the influence of potential outliers and unobserved heterogeneity. Based on 707 French crop farms observed in 2008, our simulations show that agricultural practices using less pesticide per hectare are unambiguously more cost-competitive in terms of direct inputs while inducing no other substitution costs. This cost dominance is a robust phenomenon regardless of the size and scope of crop activities, which supports more ecofriendly practices. [ABSTRACT FROM AUTHOR]

An analytical method based on dispersive solid-phase extraction with a multiwalled carbon nanotubes sorbent coupled with positive pulse glow discharge ion mobility spectrometry was developed for analysis of 30 pesticide residues in drinking water samples. Reduced ion mobilities and the mass-mobility correlation of 30 pesticides were measured. The pesticides were divided into five groups to verify the separation capability of pulse glow discharge in mobility spectrometry. The extraction conditions such as desorption solvent, ionic strength, conditions of adsorption and desorption, the amounts of multiwalled carbon nanotubes, and solution pH were optimized. The enrichment factors of pesticides were 5.4- to 48.7-fold (theoretical enrichment factor was 50-fold). The detection limits of pesticides were 0.01∼0.77 μg/kg. The linear range was 0.005-0.2 mg/L for pesticide standard solutions, with determination coefficients from 0.9616 to 0.9999. The method was applied for the analysis of practical and spiked drinking water samples. All results were confirmed by high-performance liquid chromatography with tandem mass spectrometry. The proposed method was proven to be a commendably rapid screening qualitative and semiquantitative technique for the analysis of pesticide residues in drinking water samples on site. [ABSTRACT FROM AUTHOR]

We report the first use of a paper-based device coated with nanoceria as a simple, low-cost and rapid detection platform for the analysis of organophosphate (OP) pesticides using an enzyme inhibition assay with acetylcholinesterase (AChE) and choline oxidase (ChOX). In the presence of acetylcholine, AChE and ChOX catalyze the formation of H2O2, which is detected colorimetrically by a nanoceria-coated device resulting in the formation of a yellow color. After incubation with OP pesticides, the AChE activity was inhibited, producing less H2O2, and a reduction in the yellow intensity. The assay is able to analyze OP pesticides without the use of sophisticated instruments and gives detection limits of 18 ng mL−1 and 5.3 ng mL−1 for methyl-paraoxon and chlorpyrifos-oxon, respectively. The developed method was successfully applied to detect methyl-paraoxon in spiked vegetables (cabbage) and a dried seafood product (dried green mussel), obtaining ∼95% recovery values for both sample types. The spiked samples were also analyzed using LC-MS/MS as a comparison to the developed method and similar values were obtained, indicating that the developed method gives accurate results and is suitable for OP analysis in real samples. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy spectra of dimethoate and phosmet pesticides were recorded using a Klarite substrate. Significant enhancements were achieved with dimethoate over a concentration range of 0.5–10 µg mL−1 and phosmet over a concentration range of 0.1–10 µg mL−1. The best prediction model for dimethoate pesticide was achieved with a correlation coefficient of 0.940 and a root mean square error of prediction of 0.864 µg mL−1, with the first derivative and standard normalized variate data preprocessing, and the best prediction model of phosmet pesticide was achieved with a correlation coefficient of 0.949 and a root mean square error of prediction of 0.741 µg mL−1 with the first derivative data preprocessing. Our study shows that pesticides, including dimethoate and phosmet, could be quantitatively measured at as low as 0.5 µg mL−1 level using surface-enhanced Raman technology coupled with a Klarite substrate and the results indicated that surface-enhanced Raman spectroscopy with a Klarite substrate has potential for the analysis of dimethoate and phosmet residues. [ABSTRACT FROM AUTHOR]

Objective: Chronic exposure to atrazine and other pesticides is reported to cause metabolic disorders, yet information on effects of atrazine on expression of genes relevant to mitochondrial function is largely missing. In the present study, therefore, we investigated the expression of a battery of nuclear-and mitochondrial-encoded genes involved in oxidative phosphorylation (OXPHOS) in human liver (HepG2) and rat muscle (L6) cell lines due to short-term atrazine exposure. Materials and Methods: We have determined the EC50 values of atrazine for cytotoxicity and mitochondrial toxicity (mitotoxicity) in terms of adenosine triphosphate (ATP) content in HepG2 and L6 cells. Further, the mRNA expression of nuclear- and mitochondrial-encoded genes was analyzed using quantitative real-time polymerase chain reaction. Results: The EC50 value of atrazine for mitotoxicity in HepG2 and L6 cells was found to be about 0.162 and 0.089 mM, respectively. Mitochondrial toxicity was indicated by reduction in ATP content following atrazine exposure. Atrazine exposure resulted in down-regulation of many OXPHOS subunits expression and affected biogenesis factors' expression. Most prominently, superoxide dismutase (SOD) and sirtuin 3 (SIRT3) expressions were up-regulated in HepG2 cells, whereas SIRT3 expression was alleviated in L6 cells, without significant changes in SOD levels. Mitochondrial transcription factor A (TFAM) and SIRT1 expression were significantly down-regulated in both cell lines. Conclusion: Results suggest that TFAM and SIRT1 could be involved in atrazine-induced mitochondrial dysfunction, and further studies can be taken up to understand the mechanism of mitochondrial toxicity. Further study can also be taken up to explore the possibility of target genes as biomarkers of pesticide toxicity. [ABSTRACT FROM AUTHOR]

The impact of widespread and common environmental factors, such as chemical contaminants, on infectious disease risk in amphibians is particularly important because both chemical contaminants and infectious disease have been implicated in worldwide amphibian declines. Here we report on the lone and combined effects of exposure to parasitic cercariae (larval stage) of the digenetic trematode, Acanthostomum burminis, and four commonly used pesticides (insecticides: chlorpyrifos, dimethoate; herbicides: glyphosate, propanil) at ecologically relevant concentrations on the survival, growth, and development of the common hourglass tree frog, Polypedates cruciger Blyth 1852. There was no evidence of any pesticide-induced mortality on cercariae because all the cercariae successfully penetrated each tadpole host regardless of pesticide treatment. In isolation, both cercarial and pesticide exposure significantly decreased frog survival, development, and growth, and increased developmental malformations, such as scoliosis, kyphosis, and also edema and skin ulcers. The combination of cercariae and pesticides generally posed greater risk to frogs than either factor alone by decreasing survival or growth or increasing time to metamorphosis or malformations. The exception was that lone exposure to chlorpyrifos had higher mortality without than with cercariae. Consistent with mathematical models that suggest that stress should increase the impact of generalist parasites, the weight of the evidence from the field and laboratory suggests that ecologically relevant concentrations of agrochemicals generally increase the threat that trematodes pose to amphibians, highlighting the importance of elucidating interactions between anthropogenic activities and infectious disease in taxa of conservation concern. [ABSTRACT FROM AUTHOR]

Objectives Prostate cancer is one of the most frequent cancers among men worldwide. Its etiology is largely unknown, but an increased risk has been repeatedly observed among farmers. Our aim was to identify occupational risk factors for prostate cancer among farmers in the prospective cohort study AGRICAN. Methods Data on lifetime agricultural exposures (type of crops, livestock and tasks including pesticide use, re-entry and harvesting) were collected from the enrolment questionnaire. During the period from enrolment (2005-2007) to 31 December 2009, 1672 incident prostate cancers were identified. Hazard ratios (HR) were estimated using Cox regression analysis. Results We found an increased risk for cattle breeders using insecticides [HR 1.20, 95% confidence interval (95% CI) 1.01-1.42] with a significant dose-response relationship with number of cattle treated (P for trend 0.01). A dose- response relationship was also observed with the number of hogs (P for trend 0.06). We found an excess of prostate cancer risk among people involved in grassland activities, mainly in haymaking (HR 1.18, 95% CI 1.02-1.36). Pesticide use and harvesting among fruit growers were associated with an elevated prostate cancer risk, with a two-fold increased risk for the largest area. For potato and tobacco producers, an elevated prostate cancer risk was observed for almost all tasks, suggesting a link with pesticide exposure since all of them potentially involved pesticide exposure. Conclusions Our analysis suggests that the risk of prostate cancer is increased in several farming activities (cattle and hog breeding, grassland and fruit-growing) and for some tasks including pesticide use. [ABSTRACT FROM AUTHOR]

Accurate spray characterization helps to better understand the pesticide spray application process. The goal of this research was to present the proof of principle of a droplet size and velocity measuring technique for different types of hydraulic spray nozzles using a high speed backlight image acquisition and analysis system. As only part of the drops of an agricultural spray can be in focus at any given moment, an in-focus criterion based on the gray level gradient was proposed to decide whether a given droplet is in focus or not. In a first experiment, differently sized droplets were generated with a piezoelectric generator and studied to establish the relationship between size and in-focus characteristics. In a second experiment, it was demonstrated that droplet sizes and velocities from a real sprayer could be measured reliably in a non-intrusive way using the newly developed image acquisition set-up and image processing. Measured droplet sizes ranged from 24 µm to 543 µm, depending on the nozzle type and size. Droplet velocities ranged from around 0.5 m/s to 12 m/s. The droplet size and velocity results were compared and related well with the results obtained with a Phase Doppler Particle Analyzer (PDPA). [ABSTRACT FROM AUTHOR]

Information on pesticide effects on spiders is less common than for insects; similar information for spider egg sacs is scarcer in the open literature. Spider egg sacs are typically covered with a protective silk layer. When pesticides are directly applied to egg sacs, the silk might prevent active ingredients from reaching the eggs, blocking their insecticidal effect. We investigated the impact of six water-based pesticide sprays and four oilbased aerosol products against egg sacs of brown widow spiders, Latrodectus geometricus C. L. Koch. All water-based spray products except one failed to provide significant mortality to egg sacs, resulting in successful spiderling emergence from treated egg sacs at a similar rate to untreated egg sacs. In contrast to waterbased sprays, oil-based aerosols provided almost complete control, with 94-100% prevention of spiderling emergence. Penetration studies using colored pesticide products indicated that oil-based aerosols were significantly more effective in penetrating egg sac silk than were the water-based sprays, delivering the active ingredients on most (>99%) of the eggs inside the sac. The ability of pesticides to penetrate spider egg sac silk and deliver lethal doses of active ingredients to the eggs is discussed in relation to the chemical nature of egg sac silk proteins. Our study suggests that pest management procedures primarily relying on perimeter application of water-based sprays might not provide satisfactory control of brown widow spider eggs. Determination of the most effective active ingredients and carrier characteristics warrant further research to provide more effective control options for spider egg sacs. [ABSTRACT FROM AUTHOR]

An optical biosensing method using CdTe quantum dots (QDs) and bi-enzyme-immobilized eggshell membranes for the determination of organophosphorus pesticides (OPs) has been developed. Increasing amounts of OPs led to a decrease of the enzymatic activity and thus a decrease in the production of hydrogen peroxide (H2O2), which can quench the fluorescence of the CdTe QDs. Under the optimum conditions, there was a good linear relationship between the enzyme inhibition percentage and the logarithm of paraoxon or parathion concentration in the range of 1.0 × 10−11–1.0 × 10−6 mol L−1. The detection limit (S/N = 3) of the proposed biosensors were as low as 4.30 × 10−12 mol L−1 for paraoxon and 2.47 × 10−12 mol L−1 for parathion. The bi-enzyme-immobilized eggshell membrane demonstrated a long shelf-life of at least 2 months and the results showed good repeatability. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Background: According to US-EPA report, the use of pyrethrins and pyrethroids has increased during the past decade, and their area of use included not only in agricultural settings, but in commerce, and individual household. It is known that urinary 3-PBA, major metabolite of pyrethroid, have some associations with health effect in nervous and endocrine system, however, there’s no known evidence that urinary 3-PBA have associations with obesity. Method: We used data of 3671 participants aged above 19 from the Korean National Environmental Health Survey in 2009–2011. In our analysis, multivariate piece-wise regression and logistic regression analysis were used to investigate the association between urinary 3-PBA (3-Phenoxybenzoic Acid) and BMI. Result: Log-transformed level of urinary 3-PBA had significantly positive association with BMI at the low-level range of exposure (p < 0.0001), and opposite associations were observed at the high level exposure (p = 0.04) after adjusting covariates. In piece-wise regression analysis, the flexion point that changes direction of the associations was at around 4 ug/g creatinine of urinary 3-PBA. As quintiles based on concentration of urinary 3-PBA increased to Q4, the ORs for prevalence of overweight (BMI ≥ 23 kg/m2) were increased, and the OR of Q5 was lower than that of Q4 (OR=1.810 for Q4; OR = 1.483 for Q5). In the analysis using obesity (BMI ≥ 25 kg/m2) as outcome variable, significant associations were observed between obesity and quintiles of 3-PBA, however, there were no differences between the OR of Q5 and that of Q4 (OR = 1.659 for Q4; OR = 1.666 for Q5). Conclusion: Our analysis suggested that low-level of pyrethroid exposure has positive association with BMI, however, there is an inverse relationship above the urinary 3-PBA level at 4 ug/g creatinine. [ABSTRACT FROM AUTHOR]

The rose species Rosa damascena and Rosa centifolia are cultivated for their use as perfume raw materials. The solvent extract of rose petals provides the concrete that is further transformed into the absolute. Both, concrete and absolute contain a variety of organic molecules. As a result of the lack of an adequate analytical procedure and the complexity of the matrices, the accurate quantification of pesticides in concrete and absolute remains challenging. Here we describe the first analytical method to quantify 57 pesticide residues in rose concrete and 56 pesticide residues in rose absolute. The method uses a multistep dispersive-solid phase extraction (d-SPE) cleanup followed by injection in a gas chromatography-tandem mass spectrometer. Sample preparation includes the extraction of analytes from the matrix using acetonitrile and a mixture of salts and a double clean-up step using sorbents in the form of primary and secondary amines (PSA), magnesium sulphate, C18 and graphitized carbon black (GCB). Two fortification levels, 0.025 to 0.15 and 0.5mg/kg, were assessed. For 56 pesticides, the obtained recoveries were within the range of 70% to 120 % with a relative standard deviation (RSD) lower than 20% at each spiked level. The validation parameters proved that the developed method can be used for the quantification of 57 pesticide residues in rose concrete and 56 pesticide residues in rose absolute with a limit of quantification (LOQ) ranging from 0.025 to 0.1mg/kg in concrete and from0.05 to 0.15mg/kg in absolute, depending on the active substance. [ABSTRACT FROM AUTHOR]