METHYL BROMIDE AND ETHYLENE OXIDE FUMIGATION OFSYNCHYTRIUM ENDOBIOTICUM

1970 ◽  
Vol 50 (6) ◽  
pp. 649-658 ◽  
Author(s):  
H. A. U. MONRO ◽  
C. T. BUCKLAND ◽  
O. A. OLSEN
Keyword(s):  
Ethylene Oxide ◽  
Methyl Bromide ◽  
Atmospheric Pressure ◽  
Potato Wart ◽  
Synchytrium Endobioticum

Methyl bromide (2.5% by volume) and ethylene oxide (2.0% by volume) in vacuum fumigation for 4 hr at 25 C killed all of the resting sporangia of the potato wart fungus, Synchytrium endobioticum (Schilb.) Perc. Methyl bromide was also effective at atmospheric pressure at 4.0% for 4 hr and at 0.25% for 16 hr at 25 C. No advantage was gained by mixing the two gases in any proportions. The use of these fumigants under normal commercial conditions to prevent the spread of the organism in commodities such as jute (burlap) bags is considered feasible.

Responses of Pests to Fumigation. III.—The Fumigation of Wheat containing Calandra spp.(Curculionidae) with three Fumigants, under Reduced Pressure

1953 ◽  
Vol 44 (4) ◽  
pp. 641-650 ◽  
Author(s):  
A. K. M. El Nahal
Keyword(s):  
Ethylene Oxide ◽  
Methyl Bromide ◽  
Hydrogen Cyanide ◽  
Atmospheric Pressure ◽  
Experimental Conditions ◽  
Reduced Pressure ◽  
Biological Assays ◽  
Moisture Contents ◽  
Reduced Pressures ◽  
Multifactorial Experiment

Wheat of three moisture contents was fumigated with ethylene oxide, methyl bromide and hydrogen cyanide. Both chemical and biological assays were used to follow the changing distribution of the fumigant when applied with sustained vacuum, in a vacuum fumigation with simultaneous admission of air and fumigant, or at atmospheric pressure.As these various factors were altered, in a multifactorial experiment, the changes in the fumigant distribution were also recorded chemically, and then analysed statistically. Changes in the mortality of both species of Calandra, either buried in a one-cwt sack of wheat or in the free-space, were estimated so that that part of the changes which was associated with the altered fumigant distribution was segregated by a covariance analysis and the remainder formed an estimate of the direct influence of the experimental Conditions on the susceptibility of the weevils to the fumigants.When either ethylene oxide or methyl bromide is used as a fumigant for wheat, vacuum fumigation with simultaneous admission of air and fumigant gives results, in terms of the control of Calandra spp., which are almost indistinguishable from those obtained at atmospheric pressure under comparable conditions. When hydrogen cyanide is the fumigant, atmospheric fumigation is superior, quite apart from the capital expense and other practical disadvantages of fumigations at reduced pressures.

THE CATALYTIC OXIDATION OF ETHYLENE TO ETHYLENE OXIDE

1949 ◽  
Vol 27b (11) ◽  
pp. 813-827 ◽  
Author(s):  
F. L. W. McKim ◽  
A. Cambron
Keyword(s):  
Ethylene Oxide ◽  
Catalytic Oxidation ◽  
Atmospheric Pressure ◽  
Reaction Rate ◽  
Ethylene Dichloride ◽  
Complete Oxidation ◽  
Large Excess ◽  
Ethylene Concentration ◽  
Silver Catalysts ◽  
Flow Experiments

The catalytic oxidation of ethylene to ethylene oxide was investigated in flow experiments over silver catalysts at atmospheric pressure between 260° and 350 °C. Calcium oxalate and stannous oxide were used as catalyst promoters. Close temperature control was provided by mounting the catalyst on a silver support. At 270 °C. the selectivity increased from about 25%, with ethylene in large excess, to about 55%, with oxygen in large excess. With air constant and in large excess, the over-all reaction rate was found to be proportional to the square root of the ethylene concentration. With ethylene constant and in large excess, the reaction rate was found to be roughly proportional to the oxygen concentration. The presence of methane, ethane, or propane promoted the complete oxidation of ethylene to carbon dioxide and water. In the absence of paraffins the addition of traces of ethylene dichloride only served to poison the catalyst.

scholarly journals Efficiency of detecting resting spores of Synchytrium endobioticum (potato wart disease) in infested sites of Ukraine and Georgia

2021 ◽  
Vol 8 (2) ◽  
pp. 36-48
Author(s):  
A. Zelya ◽  
L. Janse ◽  
J. Janse ◽  
S. Ghoghoberidze ◽  
G. Zelya ◽  
...  
Keyword(s):  
Organic Matter ◽  
Extraction Method ◽  
Sodium Iodide ◽  
Detection Efficiency ◽  
Extraction Methods ◽  
Inoculum Level ◽  
Potato Wart ◽  
Synchytrium Endobioticum ◽  
Resting Spores ◽  
High Level

Aim. To determine the occurrence and persistence of Synchytrium endobioticum, resting spore contamination in a small survey of (known infested) potato plots in Ukraine and Georgia; to compare the detection efficiency for resting spores (winter sporangia) of S. endobioticum using an extraction method, routinely applied in Ukraine, based on the use of sodium iodide (NaI) and an extraction method largely based on EPPO Standard PM 7/28(2) (2017), using kaolin and calcium chloride (CaCl2) for extraction. Methods. The examination of fields, aimed at detecting of S. endobioticum in 22 infested plots in Georgia, was conducted following the standard European Plant Protection Organisation (EPPO) phytosanitary procedure PM 3/59(3) (2017), and in Ukraine in 11 plots according to the Ukrainian Standard ‘Methodological recommendations on sampling during quarantine inspection and evaluation’ (Omeluta V P et al, 1996). Resting spores were extracted using kaolin and CaCl2 (following largely EPPO Standard PM 7/28(2) 2017), and floatation in a solution of NaI (Zelya et al, 2005), respectively. The content of soil organic matter (SOM), collected in potato wart infested plots in Ukraine and Georgia, was determined according to the ‘Method of laboratory determination of the content of organic matter’, largely following the method of Tyurin to determine total soil organic carbon (Jankauskas B et al, 2006). The persistence or decline of potato wart in infested plots was evaluated, based on our own observations and the data of the national phytosanitary services (https://dpss.gov.ua; http://agr.georgia.gov). The results of the study were subjected to statistical analysis, using Statistica 5 software. Results. It was found that under a low up to high level of organic matter in soil samples (2.0–2.7 and 3.1–3.9 %, respectively) and a moderate to high level of inoculum in soil (3–15 up to 41–65 resting spores/g soil, respectively) there were no significant differences in the efficiency of two extraction methods under consideration: the floatation in a solution of NaI and the application of kaolin and CaCl2. However, at a low number of resting spores present in soil (1–2 resting spores/g soil), the efficiency of the method using NaI decreased statistically significant by 20–30 % as opposed to the method using kaolin/CaCl2. A relatively high level of soil contamination with resting spores was found in 11 investigated plots of 4 Ukrainian regions: 41–46 resting spores/g soil in the Ivano-Frankivsk Region, 49 in the Lviv Region, 40–65 in the Zakarpattia and 52–65 Chernivtsi Regions. The majority of the 22 investigated Georgian plots showed a low inoculum level (1–7 resting spores/g soil) and only in one village their level amounted to 15 resting spores/g soil (Uchguli village, Mestia municipality). Conclusions. The method applying sodium iodide was found to be comparable to the method applying kaolin and CaCl2 under conditions of moderate to high inoculum levels (15–65 resting spores/g soil) but the latter method was more efficient under conditions of high content of organic matter and very low inoculum level (

scholarly journals Exposures to Fumigants and Residual Chemicals in Workers Handling Cargo from Shipping Containers and Export Logs in New Zealand

2020 ◽  
Vol 64 (8) ◽  
pp. 826-837 ◽  
Author(s):  
Ruth Hinz ◽  
Andrea ’t Mannetje ◽  
Bill Glass ◽  
Dave McLean ◽  
Neil Pearce ◽  
...  
Keyword(s):  
New Zealand ◽  
Ethylene Oxide ◽  
Methyl Bromide ◽  
Limit Of Detection ◽  
Weighted Average ◽  
Limit Values ◽  
Exposure Limit ◽  
Personal Exposures ◽  
Shipping Containers ◽  
High Concentrations

Abstract Objectives Previous studies have reported high concentrations of airborne fumigants and other chemicals inside unopened shipping containers, but it is unclear whether this is reflective of worker exposures. Methods We collected personal 8-h air samples using a whole-air sampling method. Samples were analysed for 1,2-dibromoethane, chloropicrin, ethylene oxide, hydrogen cyanide, hydrogen phosphide, methyl bromide, 1,2-dichloroethane, C2-alkylbenzenes, acetaldehyde, ammonia, benzene, formaldehyde, methanol, styrene, and toluene. Additive Mixture Values (AMVs) were calculated using the New Zealand Workplace Exposure standard (WES) and American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs) of the 8-h, time-weighted average exposure limit. Linear regression was conducted to assess associations with work characteristics. Results We included 133 workers handling shipping containers, 15 retail workers unpacking container goods, 40 workers loading fumigated and non-fumigated export logs, and 5 fumigators. A total of 193 personal 8-h air measurements were collected. Exposures were generally low, with >50% below the limit of detection for most chemicals, and none exceeding the NZ WES, although formaldehyde exceeded the TLV in 26.2% of all measurements. The AMV-TLV threshold of 1 was exceeded in 29.0% of the measurements. Levels and detection frequencies of most chemicals varied little between occupational groups, although exposure to methyl bromide was highest in the fumigators (median 43 ppb) without exceeding the TLV of 1000 ppb. Duration spent inside the container was associated with significantly higher levels of ethylene oxide, C2-alkylbenzenes, and acetaldehyde, but levels were well below the TLV/WES. Exposure levels did not differ between workers handling fumigated and non-fumigated containers. Conclusions Personal exposures of workers handling container cargo in New Zealand were mainly below current exposure standards, with formaldehyde the main contributor to overall exposure. However, as it is not clear whether working conditions of participants included in this study were representative of this industry as a whole, and not all relevant exposures were measured, we cannot exclude the possibility that high exposures may occur in some workers.

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