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Insects Dec 2021(Denis and Shiffermüller) (Lepidoptera: Tortricidae) is one of the main pests that affect the production and export of table grapes in Chile. Because this pest has...
(Denis and Shiffermüller) (Lepidoptera: Tortricidae) is one of the main pests that affect the production and export of table grapes in Chile. Because this pest has quarantine status, the fruit must be fumigated with methyl bromide, which reduces the fruit's export competitiveness in the destination market. In the present study, to help resolve this issue, six native entomopathogenic fungi were identified through multilocus analysis, including three and three . These fungi were evaluated in the laboratory to control in its pupal stage in a silk cocoon and compared against a biological control product. Formulations with additional carbon sources improved the performance of the fungi. The treatments with outstanding performance contained the fungal strains RGM 2184 and RGM 678. These strains were evaluated in the field during the winter season in two different regions of the country; the strains reached maximum efficacies of 80% and 88%, respectively, at 21 days post first application. Therefore, entomopathogenic fungi can contribute to reducing pupal populations in winter, thereby decreasing the moth population in spring-summer.
PubMed: 35055851
DOI: 10.3390/insects13010008 -
Nature Communications Jan 2022Methyl bromide (CHBr) and methyl chloride (CHCl) are major carriers of atmospheric bromine and chlorine, respectively, which can catalyze stratospheric ozone depletion....
Methyl bromide (CHBr) and methyl chloride (CHCl) are major carriers of atmospheric bromine and chlorine, respectively, which can catalyze stratospheric ozone depletion. However, in our current understanding, there are missing sources associated with these two species. Here we investigate the effect of copper(II) on CHBr and CHCl production from soil, seawater and model organic compounds: catechol (benzene-1,2-diol) and guaiacol (2-methoxyphenol). We show that copper sulfate (CuSO) enhances CHBr and CHCl production from soil and seawater, and it may be further amplified in conjunction with hydrogen peroxide (HO) or solar radiation. This represents an abiotic production pathway of CHBr and CHCl perturbed by anthropogenic application of copper(II)-based chemicals. Hence, we suggest that the widespread application of copper(II) pesticides in agriculture and the discharge of anthropogenic copper(II) to the oceans may account for part of the missing sources of CHBr and CHCl, and thereby contribute to stratospheric halogen load.
PubMed: 35013262
DOI: 10.1038/s41467-021-27779-3 -
Journal of Environmental Quality Mar 2022Soilborne pests are a major obstacle that must be overcome for the production of horticultural crops. Methyl bromide (MBr) was an effective preplanting soil...
Quantifying the effects of anaerobic soil disinfestation and other biological soil management strategies on nitrous oxide emissions from raised bed plasticulture tomato production.
Soilborne pests are a major obstacle that must be overcome for the production of horticultural crops. Methyl bromide (MBr) was an effective preplanting soil broad-spectrum biocide, but its use has been banned due to its role in depleting the ozone layer. As a result, sustainable alternative methods for controlling soilborne pathogens and pests are needed. Nitrous oxide (N O) emissions are of concern in crop production due to the role of N O as a greenhouse gas. Agricultural lands are known sources for emission of N O into the atmosphere. Emissions are related to many environmental factors as well as fertilization and fumigation practices. This study evaluated the influence of different alternatives to MBr on N O emissions throughout a tomato production season in two locations representative of southern and northern Florida. We evaluated eight soil management practices, including (a) untreated controls; (b) chemical soil fumigation; (c) anaerobic soil disinfestation using molasses (M) + composted poultry litter and (d and e) M + composted yard waste (CYW, at two rates); (f) Soil Symphony Amendment (SSA), a commercially available mix of microbes and nutrients; (g) CYW alone; and (h) CYW + SSA. Nitrous oxide emissions were measured throughout the cropping season. Emissions were highest on the day of planting (Day 21), ranging from 213 to 1,878 μg m h , likely due to the release of N O that had accumulated under the totally impermeable film when it was punctured for planting. However, statistical significance varied between sites. Estimated cumulative emissions of N O throughout the production season ranged from 1.3 to 4.8 kg N O-N ha .
Topics: Anaerobiosis; Greenhouse Gases; Solanum lycopersicum; Nitrous Oxide; Soil
PubMed: 34997770
DOI: 10.1002/jeq2.20324 -
Journal of the Air & Waste Management... Jun 2022Alfalfa hay that was grown on a field treated with a methyl bromide and chloropicrin pesticide (at a 98/2 weight ratio) resulted in animal sickness, posing a disposal...
Alfalfa hay that was grown on a field treated with a methyl bromide and chloropicrin pesticide (at a 98/2 weight ratio) resulted in animal sickness, posing a disposal issue for the harvested feed. In consideration of disposal options, emissions and residues from burning treated and untreated alfalfa hay were sampled and analyzed to provide data for an assessment of potential health and environmental effects. Treated alfalfa hay was tested in parallel with untreated alfalfa in a controlled laboratory combustion facility. Results showed that about half of the bromine and chlorine in the treated hay was emitted and the remaining was retained in the ash. The alfalfa hay burned poorly, with modified combustion efficiencies, the ratio of CO to CO + CO, below 0.89. The emission factor for PM was statistically higher for the untreated versus treated alfalfa but the PAHs were doubled in the treated alfalfa. The treated alfalfa had significantly more emissions of polychorinated dibenzodioxin/dibenzofuran than the untreated alfalfa by a factor of 10, but less polybrominated dibenzodioxin/dibenzofuran. The high Br concentration in the treated alfalfa biomass may have resulted in formation and emission of mixed halogen compounds which were unable to be analyzed for lack of standards. Comparison of volatile organic compound emissions were unremarkable with the exception of MeBr where emissions from the treated alfalfa were over 300 times higher than the untreated biomass. The potential complications due to emissions and permitting of an open burn or contained incinerator left options for landfilling and feedstock blending for handling the treated alfalfa. : This paper illustrates the issues agricultural managers must deal with concerning the combustive disposal of contaminated crops. A method is presented whereby combustion of contaminated crops can be assessed for their suitability for disposal by open air or enclosed burning.
Topics: Air Pollutants; Biomass; Bromides; Carbon Dioxide; Crops, Agricultural; Dibenzofurans; Hydrocarbons, Brominated
PubMed: 34895080
DOI: 10.1080/10962247.2021.2013343 -
American Journal of Industrial Medicine Feb 2022The Occupational Safety and Health Administration (OSHA) regulates exposures to hazardous chemicals in workplace air. When contemporaneous exposure measurements are...
BACKGROUND
The Occupational Safety and Health Administration (OSHA) regulates exposures to hazardous chemicals in workplace air. When contemporaneous exposure measurements are unavailable, retrospective analysis of biomarkers could provide valuable information about workers' exposures.
METHODS
Single-compartment pharmacokinetic (PK) models were created to relate the concentration of a chemical in the air to the concentration of the chemical or its metabolite in workers' blood or urine. OSHA utilized the PK models in investigations of three fatal incidents in which workers were exposed to nickel carbonyl, methyl bromide, or styrene. To obtain the minimum plausible estimate of each exposure, OSHA used conservative assumptions about parameters such as workers' inhalation rates, baseline levels of biomarker, and chemicals' volumes of distribution.
RESULTS
OSHA analyzed a worker's urinary nickel concentration and concluded that his 8-h time-weighted average exposure to nickel carbonyl was at least 0.06 mg/m . Analysis of a worker's postexposure, premortem blood bromide level revealed that his exposure to methyl bromide was at least 181 mg/m . Post-mortem blood styrene measurements suggested that a third worker's exposure to styrene was at least 625 mg/m . These exposures exceeded OSHA's permissible exposure limits of 0.007 mg/m for nickel carbonyl, 80 mg/m for methyl bromide, and 426 mg/m for styrene. OSHA successfully cited the three employers for violations of chemical exposure limits.
CONCLUSIONS
Analysis of biomarkers via PK modeling enables retrospective evaluations of workers' acute exposures to hazardous chemicals. These techniques are useful to occupational regulators who assess employer compliance with mandatory exposure limits.
Topics: Biological Monitoring; Humans; Occupational Exposure; Retrospective Studies; Styrene; United States; United States Occupational Safety and Health Administration
PubMed: 34865238
DOI: 10.1002/ajim.23317 -
Insects Nov 2021Recently, spotted wing Drosophila, , is globally prevalent and causes agricultural losses to many fruits. To export Korean strawberry, methyl bromide fumigation is...
Recently, spotted wing Drosophila, , is globally prevalent and causes agricultural losses to many fruits. To export Korean strawberry, methyl bromide fumigation is required to remove infestations, but Korean strawberry farmers are worried about fruit damage because methyl bromide can cause phytotoxicity on fresh commodities. In this report, we assessed the efficacy and phytotoxicity of single and successive application of methyl bromide and cold treatment on an export variety of strawberry to reduce fruit damage. The currently recommended dosage of methyl bromide, 40 g/m for 3 h at 18 °C, was enough to control all stages of without phytotoxicity. A dosage of 20 g/m of methyl bromide treatment for 3 h, followed by 1 d of cold (0 °C) treatment, showed 100% mortality in all growth stages of without fruit damage. Successive application of methyl bromide and cold treatment shows potential as a method of decreasing phytotoxicity and reducing the use of methyl bromide for environmental considerations.
PubMed: 34821790
DOI: 10.3390/insects12110990 -
Insects Oct 2021is a major pest that causes serious damage to many fruits. Although phytosanitary treatment methods have been developed for control, there is a lack of information...
is a major pest that causes serious damage to many fruits. Although phytosanitary treatment methods have been developed for control, there is a lack of information related to the gene expression pattern of . subjected to phytosanitary treatment conditions. Prior to quantitative reverse transcription polymerase chain reaction analysis of the most stable reference genes in (Diptera: Tephritidae), third-instar larvae were exposed to various phytosanitary treatments; seven candidate reference genes (18S, G6PDH, GAPDH, RPL-13, RPL-32, RPS-3, and α-Tub) were amplified and their expression stabilities were evaluated using geNorm, NormFinder, BestKeeper, and RefFinder algorithms. Different reference genes were found under different stress conditions. G6PDH was the most stable gene after heat treatment. After cold treatment, α-Tub exhibited the highest expression stability. G6PDH expression stability was the highest after fumigation with methyl bromide. RPL-32 showed the highest expression stability after irradiation treatment. Collectively, RefFinder analysis results revealed G6PDH and RPL-32 as the most suitable genes for analyzing phytosanitary treatment in . This study provides an experimental basis for further gene expression analyses in subjected to various phytosanitary treatments, which can aid in the development of novel phytosanitary treatments against insect pests.
PubMed: 34680714
DOI: 10.3390/insects12100945 -
Annals of Work Exposures and Health Apr 2022Airborne fumigants and other hazardous chemicals inside unopened shipping containers may pose a risk to workers handling containers.
BACKGROUND
Airborne fumigants and other hazardous chemicals inside unopened shipping containers may pose a risk to workers handling containers.
METHODS
Grab air samples from 490 sealed containers arriving in New Zealand were analysed for fumigants and other hazardous chemicals. We also collected grab air samples of 46 containers immediately upon opening and measured the total concentration of volatile organic compounds in real-time during ventilation. Additive Mixture Values (AMV) were calculated using the New Zealand Workplace Exposure standard (WES) and ACGIH Threshold Limit Values (TLV) of the 8-h, time-weighted average (TWA) exposure limit. Regression analyses assessed associations with container characteristics.
RESULTS
Fumigants were detectable in 11.4% of sealed containers, with ethylene oxide detected most frequently (4.7%), followed by methyl bromide (3.5%). Other chemicals, mainly formaldehyde, were detected more frequently (84.7%). Fumigants and other chemicals exceeded the WES/TLV in 6.7%/7.8%, and 7.8%/20.0% of all containers, respectively. Correspondingly, they more frequently exceeded '1' for the AMV-TLV compared to the AMV-WES (25.7% versus 7.8%). In samples taken upon opening of doors, fumigants were detected in both fumigated and non-fumigated containers, but detection frequencies and exceedances of the WES, TLV, and AMVs were generally higher in fumigated containers. Detection frequencies for other chemicals were similar in fumigated and non-fumigated containers, and only formaldehyde exceeded both the WES and TLV in both container groups. Volatile compounds in container air reduced rapidly during ventilation. Some cargo types (tyres; personal hygiene, beauty and medical products; stone and ceramics; metal and glass; and pet food) and countries of origin (China) were associated with elevated airborne chemical and fumigant concentrations.
CONCLUSION
Airborne chemicals in sealed containers frequently exceed exposure limits, both in fumigated and non-fumigated containers, and may contribute to short-term peak exposures of workers unloading or inspecting containers.
Topics: Formaldehyde; Hazardous Substances; Humans; New Zealand; Occupational Exposure; Pesticides
PubMed: 34657959
DOI: 10.1093/annweh/wxab090 -
Steroids Dec 2021Vecuronium bromide (Piperidinium, 1-[(2β,3α,5α,16β,17β)-3,17-bis(acetyloxy)-2-(1-piperidinyl)androstan-16-yl]-1-methyl-, bromide; Norcuron®) has been extensively...
Vecuronium bromide (Piperidinium, 1-[(2β,3α,5α,16β,17β)-3,17-bis(acetyloxy)-2-(1-piperidinyl)androstan-16-yl]-1-methyl-, bromide; Norcuron®) has been extensively used in anesthesiology practice as neuromuscular blocking agent since its launch on the market in 1982. However, a detailed crystallographic and NMR analysis of its advanced synthetic intermediates is still lacking. Hence, with the aim of filling this literature gap, vecuronium bromide was prepared starting from the commercially available 3β-hydroxy-5α-androstan-17-one (epiandrosterone), implementing some modifications to a traditional synthetic procedure. A careful NMR study allowed the complete assignment of the H, C, and N NMR signals of vecuronium bromide and its synthetic intermediates. The structural and stereochemical characterization of 2β,16β-bispiperidino-5α-androstane-3α,17β-diol, the first advanced synthetic intermediate carrying all the stereocenters in the final configuration, was described by means of single-crystal X-ray diffraction and Hirshfeld surface analysis, allowing a detailed conformational investigation.
Topics: Crystallography, X-Ray; Magnetic Resonance Spectroscopy; Models, Molecular; Molecular Structure; Neuromuscular Blocking Agents; Vecuronium Bromide
PubMed: 34655596
DOI: 10.1016/j.steroids.2021.108928 -
Journal of Economic Entomology Dec 2021Ethyl formate (EF) was evaluated as a potential alternative to methyl bromide (MB) for phytosanitary treatment of imported citrus fruit in the Republic of Korea....
Ethyl formate (EF) was evaluated as a potential alternative to methyl bromide (MB) for phytosanitary treatment of imported citrus fruit in the Republic of Korea. Planococcus citri (Risso) (Hemiptera: Pseudococcidae), a mealybug with known tolerance against EF and MB, was used as a representative pest to test efficacy of the two fumigants against eggs. In nine commercial-scale refrigerated container (67.5 m3) trials using imported orange, lemon and grapefruit, EF applied at the currently approved dose for citrus (70 g·m-3 at 5°C for 4 h, developed for Aspidiotus excisus Green (Hemiptera: Diaspididae), a species less EF tolerant than P. citri) resulted in 76.9-98.3% mortality of P. citri eggs. The EF treatment did not affect the sugar content or the color of peel and pulp of the treated fruit. When oranges were treated according to the current MB (64 g·m-3 at >5°C for 2 h) or EF treatment guidelines, the concentration of fumigant around the fruit fluctuated between 9.4 and 185.1 ppm for EF and 9.5-203.0 ppm for MB during the 72-h post-fumigation processes (venting [0-2 h], transportation to storage [2-24 h], and storage periods [24-72 h]) with both EF and MB maintained between 10 and 100 ppm during the storage period. Considering the efficacy of EF, its apparent lack of phytotoxicity, and its more manageable threshold limit value for humans (100 ppm EF compared to 1 ppm MB for an 8-h time weighted average exposure), our results suggest that EF may be a promising alternative to MB for the phytosanitary treatment of imported citrus in Korea.
Topics: Animals; Citrus; Formic Acid Esters; Fruit; Fumigation; Hemiptera; Hydrocarbons, Brominated; Workplace
PubMed: 34622933
DOI: 10.1093/jee/toab175