Toxic carbonyl compounds, including formaldehyde, malonaldehyde, and glyoxal, formed in mainstream cigarette smoke were quantified by derivatization-solid phase extraction-gas chromatography methods. Cigarette smoke from 14 commercial brands and one reference (2R1F) was drawn into a separatory funnel containing aqueous phosphate-buffered saline. Reactive carbonyl compounds trapped in the buffer solution were derivatized into stable nitrogen containing compounds (pyrazoles for -dicarbonyl and , -unsaturated aldehyde; quinoxalines for -dicarbonyls; and thiazolidines for alkanals). After derivatives were recovered using C 18 solid phase extraction cartridges, they were analyzed quantitatively by a gas chromatograph with a nitrogen phosphorus detector. The total carbonyl compounds recovered from regular size cigarettes ranged from 1.92 mg/cigarette À1 to 3.14 mg/cigarette À1 . The total carbonyl compounds recovered from a reference cigarette and a king size cigarette were 3.23 mg/cigarette À1 and 3.39 mg/cigarette À1 , respectively. The general decreasing order of the carbonyl compounds yielded was acetaldehyde (1110-2101 g/cigarette À1 ) > diacetyl (301-433 g/cigarette À1 ), acrolein (238-468 g/cigarette À1 ) > formaldehyde (87.0-243 g/cigarette À1 ), propanal (87.0-176 g/cigarette À1 ) > malonaldehyde (18.9-36.0 g/cigarette À1 ), methylglyoxal (13.4-59.6 g/cigarette À1 ) > glyoxal (1.93-6.98 g/cigarette À1 ).

No abstract

Delta(9)-tetrahydrocannabinol (THC), the psychoactive ingredient of marijuana, has useful medicinal properties but also undesirable side effects. The brain receptor for THC, CB(1), is also activated by the endogenous cannabinoids anandamide and 2-arachidonylglycerol (2-AG). Augmentation of endocannabinoid signaling by blockade of their metabolism may offer a more selective pharmacological approach compared with CB(1) agonists. Consistent with this premise, inhibitors of the anandamide-degrading enzyme fatty acid amide hydrolase (FAAH) produce analgesic and anxiolytic effects without cognitive defects. In contrast, we show that dual blockade of the endocannabinoid-degrading enzymes monoacylglycerol lipase (MAGL) and FAAH by selected organophosphorus agents leads to greater than ten-fold elevations in brain levels of both 2-AG and anandamide and to robust CB(1)-dependent behavioral effects that mirror those observed with CB(1) agonists. Arachidonic acid levels are decreased by the organophosphorus agents in amounts equivalent to elevations in 2-AG, which indicates that endocannabinoid and eicosanoid signaling pathways may be coordinately regulated in the brain.

Neonicotinoid insecticides are nicotinic acetylcholine receptor agonists used worldwide. Their environmental health effects including neurotoxicity are of concern. We previously determined a metabolite of acetamiprid, N-desmethyl-acetamiprid in the urine of a patient, who exhibited some typical symptoms including neurological findings. We sought to investigate the association between urinary N-desmethyl-acetamiprid and the symptoms by a prevalence case-control study. Spot urine samples were collected from 35 symptomatic patients of unknown origin and 50 non-symptomatic volunteers (non-symptomatic group, NSG, 4–87 year-old). Patients with recent memory loss, finger tremor, and more than five of six symptoms (headache, general fatigue, palpitation/chest pain, abdominal pain, muscle pain/weakness/spasm, and cough) were in the typical symptomatic group (TSG, n = 19, 5–69 year-old); the rest were in the atypical symptomatic group (ASG, n = 16, 5–78 year-old). N-desmethyl-acetamiprid and six neonicotinoids in the urine were quantified by liquid chromatography-tandem mass spectrometry. The detection of N-desmethyl-acetamiprid was the most frequent and highest in TSG (47.4%, 6.0 ppb (frequency, maximum)), followed by in ASG (12.5%, 4.4 ppb) and in NSG (6.0%, 2.2 ppb), however acetamiprid was not detected. Thiamethoxam was detected in TSG (31.6%, 1.4 ppb), in ASG (6.3%, 1.9 ppb), but not in NSG. Nitenpyram was detected in TSG (10.5%, 1.2 ppb), in ASG (6.3%, not quantified) and in NSG (2.0%, not quantified). Clothianidin was only detected in ASG (6.3%, not quantified), and in NSG (2.0%, 1.6 ppb). Thiacloprid was detected in ASG (6.3%, 0.1 ppb). The cases in TSG with detection of N-desmethyl-acetamiprid and thiamethoxam were aged 5 to 62 years and 13 to 62 years, respectively. Detection of N-desmethyl-acetamiprid was associated with increased prevalence of the symptoms (odds ratio: 14, 95% confidence interval: 3.5–57). Urinary N-desmethyl-acetamiprid can be used as a biomarker for environmental exposure to acetamiprid. Further multi-centered clinical research in larger patients groups with more metabolites analysis is needed.

The antioxidant activities of a commercial brewed coffee were investigated by measuring malonaldehyde (MA) formation from oxidized cod liver oil using a gas chromatographic method (MA-GC assay) and a thiobarbituric acid method (TBA assay). The highest antioxidant activity obtained by the MA-GC assay was from regular whole brewed coffee (97.8%) at a level of 20%, and the highest antioxidant activity obtained by the TBA assay was from decaffeinated whole brewed coffee (96.6%) at a level of 5%. Among 31 chemicals identified in a dichloromethane extract, guaiacol, ethylguaiacol, and vinylguaiacol exhibited antioxidant activities, which were comparable to that of alpha-tocopherol. Among nine chlorogenic acids (three caffeoylquinic acids, three feruloylquinic acids, and three dicaffeoylquinic acids) identified, 5-caffeoylquinic acid contained the greatest amount both in regular (883.5 microg/mL) and in decaffeinated (1032.6 microg/mL) coffees; it exhibited 24.5% activity by the MA-GC assay and 45.3% activity by the TBA assay at a level of 10 microg/mL. Caffeic and ferulic acids showed moderate antioxidant activities in both assays.

Dietary oils--tuna, salmon, cod liver, soybean, olive, and corn oils--were treated with accelerated storage conditions (60 degrees C for 3 and 7 d) and a cooking condition (200 degrees C for 1 h). Genotoxic malonaldehyde (MA), glyoxal, and methylglyoxal formed in the oils were analyzed by GC. Salmon oil produced the greatest amount of MA (1070+/-77.0 ppm of oil) when it was heated at 60 degrees C for 7 d. The highest formation of glyoxal was obtained from salmon oil heated at 60 degrees C for 3 d. More glyoxal was found from salmon and cod liver oils when they were heated for 3 d (12.8+/-1.10 and 7.07+/-0.19 ppm, respectively) than for 7 d (6.70+/-0.08 and 5.94+/-0.38 ppm, respectively), suggesting that glyoxal underwent secondary reactions during a prolonged time. The amount of methyglyoxal formed ranged from 2.03+/-0.13 (cod liver oil) to 2.89+/-0.11 ppm (tuna oil) in the fish oils heated at 60 degrees C for 7 d. Among vegetable oils, only olive oil yielded methylglyoxal (0.61+/-0.03 ppm) under accelerated storage conditions. When oils were treated under cooking conditions, the aldehydes formed were comparable to those formed under accelerated storage conditions. Fish oils produced more MA, glyoxal, and methylglyoxal than did vegetable oils because the fish oils contained higher levels of long-chain PUFA, such as EPA and DHA, than did the vegetable oils. A statistically significant correlation (P < 0.05) between the alpha-tocopherol content and the oxidation parameters was obtained from only MA and fish oils heated at 60 degrees C for 3 d.

Neonicotinoid pesticides have been widely applied for the production of fruits and vegetables, and occasionally detected in conventionally grown produce. Thus oral exposure to neonicotinoid pesticides may exist in the general population; however, neonicotinoid metabolites in human body fluids have not been investigated comprehensively. The purpose of this study is the qualitative profiling and quantitative analysis of neonicotinoid metabolites in the human spot urine by liquid chromatography coupled with mass spectrometry (LC/MS). Human urine samples were collected from three patients suspected of subacute exposure to neonicotinoid pesticides. A qualitative profiling of urinary metabolites was performed using liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) with a database of nominal molecular weights of 57 known metabolites of three neonicotinoid pesticides (acetamiprid, Imidacloprid, and clothianidin), as well as the parent compounds. Then a quantitative analysis of selected urinary metabolites was performed using liquid chromatography/tandem mass spectrometry (LC/MS/MS) with a standard pesticide and metabolite, which were detected by the qualitative profiling. The result of qualitative profiling showed that seven metabolites, i.e. an acetamiprid metabolite, N-desmethyl-acetamiprid; three Imidacloprid metabolites, 5-hydroxy-Imidacloprid, 4,5-dihydroxy-imidacloprid, 4,5-dehydro-Imidacloprid; a common metabolite of acetamiprid and Imidacloprid, N-(6-chloronicotinoyl)-glycine; and two clothianidin metabolites, N-desmethyl-clothianidin, N-(2-(methylsulfanyl)thiazole-5-carboxyl)-glycine, as well as acetamiprid, were detected in the urine of three cases. The result of the quantitative analysis showed N-desmethyl-acetamiprid was determined in the urine of one case, which had been collected on the first visit, at a concentration of 3.2 ng/mL. This is the first report on the qualitative and quantitative detection of N-desmethyl-acetamiprid in the human urine. The results suggest that the one case with detection of N-desmethyl-acetamiprid was exposed to acetamiprid through the consumption of contaminated foods. Urinary N-desmethyl-acetamiprid, as well as 5-hydroxy-Imidacloprid and N-desmethyl-clothianidin, may be a good biomarker for neonicotinoid exposure in humans and warrants further investigation.

Pesticide detoxification is a central feature of selective toxicity and safety evaluation. Two of the principal enzymes involved are GSH S-transferases (GSTs) and cytochrome P450s acting alone and together. More than 100 pesticides are organophosphorus (OP) compounds, but with few exceptions, their GSH conjugates have not been directly observed in vitro or in vivo. The major insecticides chlorpyrifos (CP) and diazinon are of particular interest as multifunctional substrates with diverse metabolites, while ClP(S)(OEt) 2 and the cotton defoliant tribufos are possible precursors of phosphorylated GSH conjugates. Formation of GSH conjugates by GST with GSH was studied in vitro with and without metabolic activation by human liver microsomes or P450 3A4 with NADPH. Metabolites were analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). Five GSH conjugates were identified from CP and chlorpyrifos oxon (CPO), i.e., GSCP and GSCPO in which the 6-chloro substituent of CP and CPO, respectively, is displaced by GSH; S-(3,5,6-trichloropyridin-2-yl)glutathione; S-(3,5-dichloro-6-hydroxypyridin-2-yl)glutathione; and S-ethylglutathione. GST of a human liver microsomal preparation but not P450 3A4 with GSH metabolized CP to GSCP. With GST and GSH, diazinon and diazoxon gave S-(2-isopropyl-4-methylpyrimidin-6-yl)glutathione and ClP(S)(OEt) 2 yielded GSP(S)(OEt) 2. With microsomes, NADPH, GST, and GSH tribufos gave GSP(O)(SBu) 2. The liver of intraperitoneally treated mice contained GSCP from CP, GSP(S)(OEt) 2 from ClP(S)(OEt) 2, and GSP(O)(SBu) 2 from tribufos. GSP(S)(OEt) 2 and GSP(O)(SBu) 2 are the first S-phosphoglutathione metabolites observed in vitro and in vivo directly by LC-ESI-MS. Nine other OP pesticides gave only O-dealkylation in the GST/GSH system. GST-catalyzed metabolism joins P450s and hydrolases as important contributors to OP detoxification.