A survey of the potency of Japanese illicit cannabis in fiscal year 2010.

In recent years, increased 'cannabis potency', or Δ(9)-tetrahydrocannabinol (THC) content in cannabis products, has been reported in many countries. A survey of Japanese illicit cannabis was conducted from April 2010 to March 2011. In Japan, all cannabis evidence is transferred to the Minister of Health, Labour and Welfare after criminal trials. The evidence was observed at Narcotics Control Department offices in major 11 cities. The total number of cannabis samples observed was 9072, of which 6376 were marijuana. The marijuana seizures were further classified, and it was found that in terms of the number of samples, 65.2% of them were seedless buds, and by weight 73.0% of them were seedless buds. Seedless buds were supposed to be 'sinsemilla', a potent class of marijuana. THC, cannabinol (CBN) and cannabidiol (CBD) in marijuana seizures exceeding 1g were quantified. The number of samples analyzed was 1115. Many of them were shown to contain CBN, an oxidative product from THC. This was a sign of long-term storage of the cannabis and of the degradation of THC. Relatively fresh cannabis, defined by a CBN/THC ratio of less than or equal to 0.1, was chosen for analysis. Fresh seedless buds (335 samples) contained an average of 11.2% and a maximum of 22.6% THC. These values are comparable to those of 'high potency cannabis' as defined in previous studies. Thus, this study shows that highly potent cannabis products are distributed in Japan as in other countries.

False positives and false negatives with a cocaine-specific field test and modification of test protocol to reduce false decision.

The specificity of the Scott test, which is widely used in the field to detect cocaine, was investigated. Several drugs and medicines were applied to the test, and the conditions leading to false positives or false negatives were defined. The Scott test consists of three steps, each involving the addition of a certain reagent and observation of the color that consequently develops. In the first step, blue precipitates appear. In the second, these precipitates completely disappear. In the third step, blue appears again, but in the lower layer. It became clear that proper sample size is critical for correct decision, since too much heroin or dibucaine showed exactly the same color sequence as cocaine HCl and thus gave false positives, and too much cocaine HCl showed persisting precipitates in the second step, yielding a false negative. The appropriate sample size was 1mg or smaller. Freebase (crack) cocaine gave false negatives even when the sample size was appropriate, and it could not be distinguished from a newer substance of abuse, 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT, foxy). The authors developed a new protocol to distinguish crack from 5-MeO-DIPT.

[An experimental proficiency test for ability to screen 104 residual pesticides in agricultural products].

An experimental proficiency test program for ability to screen 104 residual pesticides in agricultural products has been conducted. Eight Japanese laboratories joined the program. Items tested in the present study were limit of detection, internal proficiency test (self spike) and external proficiency test (blind spike). All 104 pesticides were well detected and recovered from agricultural foods in the internal proficiency test. However, the results of the external proficiency test did not completely agree with those of the internal proficiency tests. After 5 rounds of the blind spike test, the ratio of the number of correctly detected pesticides to that of actually contained ones (49 total) ranged from 65% to 100% among laboratories. The numbers of mistakenly detected pesticides by a laboratory were 0 to 15. Thus, there was a great difference among the laboratories in the ability to screen multiresidual pesticides.

[Migration of di(2-ethylhexyl) phthalate from polyvinyl chloride tubes used in preparation of foods].

Three samples of polyvinyl chloride products for food use were examined for di(2-ethylhexyl) phthalate (DEHP) migration levels under the conditions described in the Japanese Food Sanitation Law. These samples were two kinds of tubes and one stretched film, containing 12 to 41% DEHP by weight. DEHP migration levels from them were very low, all below 0.1 ppm, into 3 kinds of food simulant; water, 4% acetic acid and 20% ethanol. However, high levels of DEHP migrated into n-heptane, 12 ppm from the stretched film sample and more than 800 ppm from the tube samples. Migration from the 2 tubes was higher than 150 ppm, the limit of residues after evaporation in containers and wraps. Though the limit of residues after evaporation is not set for equipment used in the preparation of foods, the tested tubes were considered to be unsuitable for uses in which they come into direct contact with oils, fats or oily foods.

[Simultaneous determination of N-methylcarbamates and their metabolites in citrus fruits by HPLC avoiding use of halogenic solvents].

Twenty-one N-methylcarbamates (NMCs) and 12 of their metabolites or isomers in citrus fruits were simultaneously determined avoiding use of dichloromethane. NMCs in lemon, orange, and grapefruit were extracted with acetone, then the acetone was evaporated off and sodium chloride was added before extraction with ethyl acetate. The extract was evaporated and the residue was cleaned up on a combined mini-column set of Supelclean ENVI-Carb and Mega Bond Elut SAX cartridges. NMCs were determined by HPLC with post-column reaction and fluorescence detection. All of the NMCs in the orange sample were determined without interfering peaks. However 8 NMCs in lemon extract and 10 NMCs in grapefruit extract were not detected because interfering peaks appeared at similar retention times to those of the NMCs. These NMCs were determined using LC/MS (SIM) and were well recovered. Eighty-three data sets obtained by HPLC and LC/MS showed good similarity, with r2 = 0.9178. Recoveries were 60.1 to 97.8% for major NMCs at a fortification level of 0.1 ppm. The limit of detection by HPLC was 0.005 ppm NMCs in samples and a similar level applied to LC/MS.

[Contents of plasticizers in cap-sealing for bottled food and their migration into food].

Plasticizers in cap-sealing for bottled foods were analyzed. Twenty-three domestic samples and 80 imported samples, a total of 103 samples, were tested. Among them, 93 contained chloride, and 62 contained di(2-ethylhexyl) phthalate (DEHP), diisodecyl phthalate, O-acetyl tributyl citrate, diacetyllauroyl glycerol, di(2-ethylhexyl) adipate, diisononyl phthalate or dicyclohexyl phthalate. Twelve samples with DEHP-containing caps were further tested for plasticizer levels in the foods. Higher DEHP was detected in oily and fluid food specimens. However, the intake of plasticizers calculated based on usual food consumption did not exceed the tolerable daily intake level in any of the cases. A food sample containing the highest level of DEHP was stored under various conditions, and DEHP that migrated from the cap-sealing into the food was determined. Shaking the bottles increased migration of DEHP into foods.

Analysis of Phenothrin and Its Metabolite 3-Phenoxybenzoic Acid (PBA) in Agricultural Products by GC and Ion-Trap GC/MS.

A sensitive method for analysis of phenothrin and its metabolite 3-phenoxybenzoic acid (PBA) in agricultural products by gas chromatography with electron capture detection (ECD-GC) and ion-trap gas chromatography/mass spectrometry (GC/MS) with chemical ionization (Cl) was investigated. After phenothrin in vegetables, fruits, potatoes, starches, and tea had been extracted with acetone, or in cereals and beans had been extracted with acetonitrile followed by Florisi! column chromatography, it was reextracted into n-hexane. PBA was determined by ECD-GC after esterification with hexafluoroisopropyl alcohol (HFIP) and diisopropylcarbodiimide (DIC). Phenothrin was determined by monitoring its molecular ion peak using ion-trap GC/MS and was confirmed by observing its spectral pattern. The detection limit for phenothrin by ECD-GC and ion-trap GC/MS by this method was 0.01 ppm. The detection limit for PBA by ECD-GC was 0.001 ppm. When phenothrin and PBA were added to samples at 0.2 and 1.0 ppm, the recoveries of phenothrin in each agricultural product ranged between 60.2 and 88.5% and those of PBA ranged between 37.8 and 89.5%. An actual-conditions surveillance analysis of six agricultural products imported from October to December 1994 indicated no phenothrin, but PBA was detected in all products.

Simultaneous Determination of Aldicarb, Ethiofencarb, Methiocarb and Their Oxidized Metabolites in Grains, Fruits and Vegetables by High Performance Liquid Chromatography.

Three carbamate pesticides, aldicarb (A0), ethiofencarb (E0), methiocarb (M0) and six of their oxidized metabolites, sulphoxides (A1, E1, M1) and sulphones (A2, E2, M2) were simultaneously determined. Five grams of a sample were homogenized with acetone, and then treated with dichloromethane-hexane mixture (1:1) and sodium chloride (NaCl), homogenized and centrifuged. The organic layer was removed and the aqueous residue was reextracted a second time with dichloromethane - hexane mixture. The combined organic extracts were evaporated in vacuo. The residue was dissolved in dichloromethane and charged on a Sep-Pak® aminopropyl cartridge. Carbamates were eluted from the cartridge with 1% methanol in dichloromethane. The eluate was evaporated to dryness and 0.5 ml of methanol and 1.5 ml of 0.001 N-hydrochloric acid (HCl) solution were added. Individual carbamates were separated by gradient elution high performance liquid chromatography (HPLC) using octyldecylsaline (ODS) column. Derivatization of separated carbamates to fluorescent derivatives was achieved in-line. Recovery of pesticides and their oxidized metabolites from rice, apple, cabbage and other foods ranged from 60 to 103% following fortification at 20 ppb. Detection limits were 1 ppb for A1, A2, E1, E2, 2 ppb for A0, E0, M1 and 4 ppb for M0 and M2 (S/N>3).

Simultaneous Determination of Aldicarb, Ethiofencarb, Methiocarb and Their Oxidized Metabolites in Grains, Fruits and Vegetables by High Performance Liquid Chromatography.

Three carbamate pesticides, aldicarb (A0), ethiofencarb (E0), methiocarb (M0) and six of their oxidized metabolites, sulphoxides (A1, E1, M1) and sulphones (A2, E2, M2) were simultaneously determined. Five grams of a sample were homogenized with acetone, and then treated with dichloromethane-hexane mixture (1:1) and sodium chloride (NaCl), homogenized and centrifuged. The organic layer was removed and the aqueous residue was re-extracted a second time with dichloromethane - hexane mixture. The combined organic extracts were evaporated in vacuo. The residue was dissolved in dichloromethane and charged on a Sep-Pak® aminopropyl cartridge. Carbamates were eluted from the cartridge with 1% methanol in dichloromethane. The eluate was evaporated to dryness and 0.5 ml of methanol and 1.5 ml of 0.001 N-hydrochloric acid (HCl) solution were added. Individual carbamates were separated by gradient elution high performance liquid chromatography (HPLC) using octyldecylsaline (ODS) column. Derivatization of separated carbamates to fluorescent derivatives was achieved in-line. Recovery of pesticides and their oxidized metabolites from rice, apple, cabbage and other foods ranged from 60 to 103% following fortification at 20 ppb. Detection limits were 1 ppb for A1, A2, E1, E2, 2 ppb for A0, E0, M1 and 4 ppb for M0 and M2 (S/N>3).

Simultaneous Determination of Vamidothion and Its Oxidation Metabolites in Potatoes and Apples by Gas Chromatography.

A method for simultaneous determination of vamidothion (V0) and its oxidation metabolites vamidothion sulphoxide (V1) and vamidothion sulphone (V2) in potatoes and apples has been developed. Fifty grams of a sample was homogenized and extracted with acetone followed by evaporation to remove the acetone. To the residual aqueous solution, a 10% sodium chloride solution was added, and the coextractives were eliminated by washing the aqueous solution with 10% ethyl acetate in hexane. Then, V0, V1, and V2 were extracted from the aqueous solution using dichloromethane. The organic layer was evaporated to dryness and filled up to 2 ml with ethyl acetate. Two microliters of the extract were injected into gas chromatograph-mass spectrometer set for selected ion monitoring. The column used was a CBP-1 capillary column (0.2 mm inside diameter × 15 m, 0.25 µm film thickness). Gas chromatographic conditions were investigated in detail and only nonpolar capillary columns gave satisfactory results. The retention time of undecomposed V1 has been reported for the first time. The recoveries for the fortified potatoes and apples were 93-109% for V0, 62-108% for V1, and 64-89% for V2, when they were fortified at levels of 0.01-5.0 ppm. Detection limits were 0.01, 0.2, and 0.05 ppm for V0, V1, and V2, respectively.