A method was developed to determine the combined amounts of residual, free 3-phenoxybenzyl alcohol (permethrin alcohol) and its acetone-extractable glucosides in representative fruits and vegetables after application of pyrethyroid insecticides such as permethrin or cypermethrin. 3-Phenoxybenzyl glucoside was synthesized and used to spike food samples. Conditions were developed for extraction, enzymatic hydrolysis, derivatization with heptafluorobutyric anhydride, and cleanup prior to detection and quantitation by gas chromatography with electron capture detection. Limits of detection in various foods were < or = 0.01 ppm. In addition, 2 sets of field trial samples that were sprayed with permethrin and collected at intervals were also analyzed. In general, the amounts of total permethrin alcohol in foods were small.

It can be concluded that HBB used in this study was more porphyrinogenic than HCB. The results suggest that HBB was an effective porphyrinogen even at a concentration in the liver of only 1/8 that of HCB. Further studies should be encouraged to determine the biochemical and pharmacological significance of HBB in the development of hepatic phorphyria. The effects of lactation on the body burden of HBB or HCB should also be investigated.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffects of hexachlorobenzene or hexabromobenzene on body and organ weights of preweanling rats after a reciprocal transfer between the treated and control damsCelso E. Mendoza, Brian T. Collins, John B. Shields, and Gary W. LaverCite this: J. Agric. Food Chem. 1978, 26, 4, 941–945Publication Date (Print):July 1, 1978Publication History Published online1 May 2002Published inissue 1 July 1978https://pubs.acs.org/doi/10.1021/jf60218a005https://doi.org/10.1021/jf60218a005research-articleACS PublicationsRequest reuse permissionsArticle Views61Altmetric-Citations11LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The effects of hexabromobenzene on adult male Wistar rats were studied. The rats were fed daily, ad libitum , a diet containing 0, 10, 20, 40, 80, or 160 ppm of hexabromobenzene (HBB) for 12 weeks. The body weights were determined and a hematological examination was performed before commencing the experiment and every third week thereafter. The rats were sacrificed at the end of Week 12. The results indicated that in general no significant difference in hematological parameters and body or organ weights were observed between the treated and control rats. The porphyrin concentrations and the esterase activity towards indophenyl acetate (IPA) and p -nitrophenyl acetate (PNPA) in the liver were also unaffected by HBB. However, serum carboxylesterase activity toward IPA was significantly induced at 60, 80, and 160 ppm of HBB. Serum carboxylesterase activity toward PNPA and thiophenyl acetate was not affected at any HBB level. The residue concentrations in fat tissues were dose-dependent and were below the detectable limit of 0.1 ppm in liver tissues of rats fed ≤40 ppm of HBB in the diet.

1. The esterase activity towards thiophenyl acetate and p-nitrophenyl acetate was determined in serum obtained from human, guinea pig, sheep, cat, dog and rat. The esterases were characterized based on their ability to hydrolyze or to be inhibited by malaoxon, fenetroxon and paraoxon.

Female Wistar rats were divided into two groups. One group was fed ad libitum powdered rat chow containing 80 ppm hexachlorobenzene (HCB) and the other was fed HCB-free diet 2 weeks before mating until the termination of the experiment. Immediately after parturition, the pups were randomly culled to 10 per litter and 5 pups were reciprocally transferred between HCB and control dams. All pups within same paired litters were sacrificed on the 16th to 17th day and on the 20th to 23rd day after birth. Liver esterase activity toward indophenyl, thiophenyl, and p-nitrophenyl acetates was determined. The liver to body weight ratio, liver esterase activity and HCB residues were significantly higher in pups nursed by HCB-fed dams than in those nursed by control dams. The HCB residue in the liver, kidney, spleen, heart and brain was analyzed by gas-liquid chromatography. At about the weaning time, the HCB residue levels in pups transferred after parturition from HCB fed to control dams were similar to those in pups which remained with the control dams. The results demonstrated that HCB in tissues at about weaning time was obtained largely through milk. In addition, transmission of HCB through milk had greater effects on esterase activities in suckling pups than placental transmission. The pups born to HCB-treated dams and nursed by the control dams were similar to the pups born and nursed by the same control dams.

1. The distribution of arylesterase activity towards thiophenyl acetate (TPA) has been determined in blood sera obtained from man, monkey, guinea pig, sheep, dog, cat and rat.

The effects of hexachlorobenzene (HCB) on the LD50 value for malathion and on tissue cholinesterase and carboxylesterase activities were studied in suckling pups of Wistar rats. The dams were fed a diet containing 80 ppm of HCB ad libitum from 2 weeks before mating to the time the litter was sacrificed. HCB obtained by the pups through milk and partially through the placenta increased by more than a factor of two the LD50 value for malathion in 17–18-day old pups. It also increased the content of liver esterases catalyzing the hydrolysis of indophenyl acetate, without any change in the liver cholinesterase activity. Reduction of inhibition of cholinesterase activities was observed in the HCB-treated groups. The increased resistance to intoxication by malathion or reduction of esterase Inhibition was attributed to an increase in tissue carboxylesterase activity, presumably malathionase, and a decrease in malaoxon formation.

The hexachlorobenzene (HCB) and porphyrin accumulation in the ograns of 18-day-old Wistar rats, whose mothers were fed a diet containing 80 ppm HCB, were studied. Among the organs examined, the highest HCB residue was in the liver larger than kidney larger than or equal to lung larger than brain larger than spleen larger than heart. The porphyrin level in the liver of the HCB-treated. On the contrary, the weights of the kidney, brain, spleen and heart were significantly reduced. Sex did not influence the organ weight except that of the brain. The results suggested that accumulation of HCB in different organs and porphyrin in the liver of suckling Wistar rats was about equal for the males and females.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTResidues of maneb, ethylenethiuram monosulfide, ethylenethiourea, and ethylenediamine on beans and tomatoes field treated with manebWilliam H. Newsome, John B. Shields, and David C. VilleneuveCite this: J. Agric. Food Chem. 1975, 23, 4, 756–758Publication Date (Print):July 1, 1975Publication History Published online1 May 2002Published inissue 1 July 1975https://pubs.acs.org/doi/10.1021/jf60200a057https://doi.org/10.1021/jf60200a057research-articleACS PublicationsRequest reuse permissionsArticle Views62Altmetric-Citations23LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMicrocolumn apparatus for rapid cleanup of 2,4-dinitrophenylmethylamine extracts for carbamate pesticide analysisCelso E. Mendoza and John B. ShieldsCite this: J. Agric. Food Chem. 1974, 22, 3, 528–530Publication Date (Print):May 1, 1974Publication History Published online1 May 2002Published inissue 1 May 1974https://pubs.acs.org/doi/10.1021/jf60193a030https://doi.org/10.1021/jf60193a030research-articleACS PublicationsRequest reuse permissionsArticle Views27Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of methomyl by using 1-fluoro-2,4-dinitrobenzene reaction and gas-liquid chromatographyCelso E. Mendoza and John B. ShieldsCite this: J. Agric. Food Chem. 1974, 22, 2, 255–258Publication Date (Print):March 1, 1974Publication History Published online1 May 2002Published inissue 1 March 1974https://pubs.acs.org/doi/10.1021/jf60192a029https://doi.org/10.1021/jf60192a029research-articleACS PublicationsRequest reuse permissionsArticle Views48Altmetric-Citations7LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

AbstractMethomyl added to rape seeds, oils or meals was detected by a thin‐layer chromatographic‐enzyme inhibition technique. The limit of detection in the presence of oil or meal extractive was 20 mg or 0.01 mg/kg. The amounts of methomyl recovered from oils and meals fortified at 0.01 to 20 mg/kg were comparable to the standard. When stored at 4 °C, methomyl in oil or meals, or in chloroform extracts, was stable for at least 10 and 21 days, respectively. No degradation was observed when methomyl was heated in ethanol at 72 °C for 2 h.Methomyl and its oxime were also detected with either iodo‐ or chloroplatinate reagent after t.l.c. The detection limits were approximately 600 mg for methomyl and 190 for the oxime.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of some carbamates by enzyme inhibition techniques using thin-layer chromatography and colorimetryCelso E. Mendoza and John B. ShieldsCite this: J. Agric. Food Chem. 1973, 21, 2, 178–184Publication Date (Print):March 1, 1973Publication History Published online1 May 2002Published inissue 1 March 1973https://pubs.acs.org/doi/10.1021/jf60186a045https://doi.org/10.1021/jf60186a045research-articleACS PublicationsRequest reuse permissionsArticle Views103Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Abstract Quantitative GLC analysis of Dyrene in tomato and strawberry extracts was accomplished by using a column of Chromosorb W (HP) coated with 1.5% OV-17/1.95% QF-1 silicones. This column adequately resolved Dyrene, methoxy-Dyrene, and dimethoxy-Dyrene. Statistical analysis showed that recoveries based on the ratios of Dyrene recovered and the Dyrene standard added to blank extracts were more consistent than those based on the standard alone.