Formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) in oxidation of captan pesticide

Chen, Kai; Wojtalewicz, D.; Altarawneh, Mohammednoor; Mackie, John C.; Kennedy, Eric M.; Dlugogorski, Bogdan Z.

doi:10.1016/j.proci.2010.07.069

Cited by 24 publications

(18 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A laminar flow reactor presents an alternative approach to JSR to elucidate the oxidation reaction of linseed oil at low temperatures, with literature examples including investigations of the pyrolysis and oxidation of catechol, captan, folpet and alpha-cypermethrin (Chen et al 2011a;Chen et al 2011b;Summoogum et al 2011;Thomas et al 2007;Wornat et al 2001). A typical experimental apparatus comprises a vaporiser, isothermal flow reactor and a product collection system as shown in Figure 8.…”

Section: Measurement Of Oxidation Of Linseed Oilmentioning

confidence: 99%

Low temperature oxidation of linseed oil: a review

et al. 2012

View full text Add to dashboard Cite

This review analyses and summarises the previous investigations on the oxidation of linseed oil and the self-heating of cotton and other materials impregnated with the oil. It discusses the composition and chemical structure of linseed oil, including its drying properties. The review describes several experimental methods used to test the propensity of the oil to induce spontaneous heating and ignition of lignocellulosic materials soaked with the oil. It covers the thermal ignition of the lignocellulosic substrates impregnated with the oil and it critically evaluates the analytical methods applied to investigate the oxidation reactions of linseed oil. Initiation of radical chains by singlet oxygen ( 1 Δ g ), and their propagation underpin the mechanism of oxidation of linseed oil, leading to the self-heating and formation of volatile organic species and higher molecular weight compounds. The review also discusses the role of metal complexes of cobalt, iron and manganese in catalysing the oxidative drying of linseed oil, summarising some kinetic parameters such as the rate constants of the peroxidation reactions. With respect to fire safety, the classical theory of self-ignition does not account for radical and catalytic reactions and appears to offer limited insights into the autoignition of lignocellulosic materials soaked with linseed oil. New theoretical and numerical treatments of oxidation of such materials need to be developed. The self-ignition induced by linseed oil is predicated on the presence of both a metal catalyst and a lignocellulosic substrate, and the absence of any prior thermal treatment of the oil, which destroys both peroxy radicals and singlet O 2 sensitisers. An overview of peroxyl chemistry included in the article will be useful to those working in areas of fire science, paint drying, indoor air quality, biofuels and lipid oxidation.

show abstract

Section: Measurement Of Oxidation Of Linseed Oilmentioning

confidence: 99%

Low temperature oxidation of linseed oil: a review

et al. 2012

View full text Add to dashboard Cite

show abstract

“…For the sake of comparison, the yield of each product in percentage (%) mentioned below denotes the mole percent of an initial reactant loading. The results of the decomposition of captan and folpet included hereafter are extracted from our previous studies on these two fungicides [10][11][12]. The experimental observation of the present research combined with those from our previous investigations on captan and folpet prompt us to make the following comments on the formation pathways of major species from captafol and hence comparison among the sulfenimide fungicides.…”

Section: Resultsmentioning

confidence: 79%

“…The further oxidation of the chlorinated benzenes leads to the formation of PCDD/F through gas phase interactions [31]. The emission of PCDD/F in the oxidation of captan and folpet amounts to 21.5 µg·g -1 and 10.7 µg·g -1 respectively [11,12], significantly lower than that of captafol (30.8 µg·g -1 ). In addition, penta-to heptachlorinated congeners of PCDD/F are detected only in the experiments with captafol.…”

Section: Resultsmentioning

confidence: 99%

“…Owing to the widespread applications of sulfenimide fungicides in agriculture and industry, in the latter as feedstocks for chemical synthesis, our group has previously studied the formation of toxic air pollutants and PCDD/F in oxidation of captan and folpet [10][11][12]. These two fungicides exhibit similar chemical structures, with the characteristic thiotrichloromethyl group bonded to tetrahydrophthalimide (THPI) moiety in captan and phthalimide (PI) in folpet, respectively (Fig.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Toxicants Formed in Fires of Captafol Pesticide

Chen¹,

Wojtalewicz²,

Mackie³

et al. 2011

Fire Safety Science - Proceedings of the 10th International Sym

View full text Add to dashboard Cite

This study presents an investigation into the gas phase thermal decomposition of captafol, a sulfenimide fungicide which consists of a thiotetrachloroethyl (-SCCl 2 CHCl 2 ) group bonded to a tetrahydrophthalimide (C 6 H 8 (CO) 2 N-) moiety. The experiments were performed on a bench type apparatus, under conditions representing both under and well-ventilated non-flaming fires. The analyses of gaseous species relied on Fourier transform infra-red spectroscopy (FTIR) and micro gas chromatography (µGC), resulting in the identification and quantification of 11 gaseous products; among them, phosgene, thiophosgene and hydrogen cyanide. Gas chromatography -quadrupole mass spectrometry (GC-QMS) was employed to analyse the condensed products and volatile organic compounds (VOC), while a GC equipped with an ion trap mass spectrometer (GC-ITMS) was used to quantify polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F). The GC-QMS analysis determined several VOC toxicants; viz., trichloroethylene, tetrachloroethylene, benzonitrile and chlorinated benzenes. At higher temperature (600 °C), the oxidation of captafol led to the formation of mono-to hepta-CDD/F congeners including the most toxic 2,3,7,8-TCDD. In addition, the experimental results were compared to those of the other two sulfenimide fungicides, captan and folpet, both of which contain the thiotrichloromethyl (-SCCl 3 ) moiety rather than the thiotetrachloroethyl group of captafol. It appears that the thiotetrachloroethyl group in captafol is responsible for the difference in the toxic pollutants formed, particularly influencing the distribution and yields of PCDD/F congeners. Combined with quantum chemical calculations, the results presented in this article provide an insightful understanding of fire chemistry of the sulfenimide fungicides, especially the pathways to the formation of major toxicants during the oxidative thermal decomposition of captafol.

show abstract

“…1 and with the details of the apparatus described elsewhere [15][16][17][18]. the fuel equivalence ratio of 0.04.…”

Section: Description Of Experimental Facilitymentioning

confidence: 99%

Formation of Polychlorinated Dibenzo-p-Dioxins and Polychlorinated Dibenzofurans and Their Precursors in Fires of Pyrethroid Pesticide Alpha-Cypermethrin

Summoogum¹,

Wojtalewicz²,

Mackie³

et al. 2011

Fire Safety Science - Proceedings of the 10th International Sym

View full text Add to dashboard Cite

This study reports the results of the gas phase oxidation of alpha-cypermethrin, a common insecticide, elucidating the decomposition pathways and formation of toxic species such as polychlorinated dibenzo-pdioxins and polychlorinated dibenzofurans (PCDD/F) and their precursors. Conditions investigated are similar to those encountered in post combustion and cooling-down zones of forest, agricultural and wild fires, as well as in burning of biomass contaminated or treated with pesticides. The experiments were conducted under fuel lean conditions in a tubular reactor housed in a three-zone heating furnace and operated with a dilute stream of alpha-cypermethrin in ultra high purity nitrogen and oxygen. PCDD/F were identified and quantified by high resolution gas chromatography (HRGC)-ion trap mass spectrometry (ITMS). We detected mono to hepta chlorinated dibenzo-p-dioxins and dibenzofurans with maximum emission factors of 141 μg g of alpha-cypermethrin. 1-monochlorodibenzofuran was ranked as the most abundant congener. We also conducted the analyses of volatile organic compounds (VOC) attempting to identify the PCDD/F precursors by means of HRGCquadrupole mass spectrometry (QMS). The results of VOC revealed chlorobenzene, diphenyl ether, benzaldehyde, chlorotoluene, dichlorotoluene as important PCDD/F precursors.

show abstract

Formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) in oxidation of captan pesticide

Cited by 24 publications

References 27 publications

Low temperature oxidation of linseed oil: a review

Low temperature oxidation of linseed oil: a review

Toxicants Formed in Fires of Captafol Pesticide

Formation of Polychlorinated Dibenzo-p-Dioxins and Polychlorinated Dibenzofurans and Their Precursors in Fires of Pyrethroid Pesticide Alpha-Cypermethrin

Contact Info

Product

Resources

About