Over the past three decades, a substantial body of evidence has accumulated on the estrogenic activities of numerous environmental compounds. These “environmental estrogens,” consisting of pesticides and a variety of industrial chemicals and their by-products, are becoming ubiquitous in the environment and are making their way into the food chain. An important issue is whether vertebrate animals are equipped with mechanisms for the inactivation and/or disposal of environmental estrogens. This review attempts to summarize the currently available data concerning the sulfation of environmental estrogenic compounds by the cytosolic sulfotransferases in vertebrate animals. © Pesticide Science Society of Japan

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Flubendiamide, N²-[1,1-dimethyl-2-(methylsulfonyl)ethyl]-3-iodo-N¹-[2-methyl-4-[1,2,2,2-tetrafluoro-1-(trifluoromethyl)ethyl]phenyl]-1,2-benzenedicarboxamide, is a novel class of insecticide having a unique chemical structure. The uniqueness of the structure results from three parts with novel substituents; a heptafluoroisopropyl group in the anilide moiety, a sulfonylalkyl group in the aliphatic amide moiety, and an iodine atom at the 3-position of the phthalic acid moiety. The compound shows extremely strong insecticidal activity especially against lepidopterous pests including resistant strains. Flubendiamide would have a novel mode of action, because the insecticidal symptoms accompanied by a discriminative contraction of the larval body are distinguished from those of commercial insecticides. It is also very safe for non-target organisms. Flubendiamide is expected to be a suitable agent for controlling lepidopterous insects as part of the insect resistance management and the integrated pest management programs. © Pesticide Science Society of Japan

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GC-EAD and GC-MS analyses of a pheromone gland extract from virgin females of the citrus leafminer (CLM, Phyllocnistis citrella Stainton) confirmed that the male attractant previously found by random screening tests in a field, (7Z,11Z)-7,11-hexadecadienal (Z7,Z11-16:Ald), is a real pheromone component of CLM. While a field test of lures mixed with extra compounds structurally related to Z7,Z11-16:Ald did not inform candidates for a minor component having a synergistic effect, some compounds, particularly monoenyl derivatives, strongly inhibited the activity of the dienyl pheromone component. Furthermore, two experiments were carried out in citrus orchards to develop a method for disrupting the mating of CLM. In order to estimate the disruptive ability of Z7,Z11-16:Ald and some derivatives, pheromone traps surrounded with septa impregnated with these test compounds were used. However, this first trial was fruitless because the number of captured males actually increased due to the effect of the surrounding compounds such as Z7,Z11-16:Ald. On the other hand, another experiment with polyethylene dispensers containing Z7,Z11-16:Ald revealed a good ability to disrupt the male's orientation, although CLM eggs and larvae on a citrus tender flush did not show any significant difference in the control and treated fields. Monitoring traps caught 27–127 males in one night in control fields from July to September, but hardly any males were caught in either field treated with the dispensers at a density of 500 or 1300 tubes/ha. © Pesticide Science Society of Japan

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A method was established for the determination of 180 pesticide residues in fruits and vegetables. The procedure involved extraction with acetonitrile, followed by a salting-out step with anhydrous MgSO₄ and NaCl. Removal of sediment and water was performed simultaneously by centrifugation. Co-extractives were removed with a double-layered SPE column, and graphitized carbon black and primary secondary amine (GCB/PSA) solid phase extraction cleanup cartridge. The eluate was determined by GC/FPD and GC/MS without further cleanup. Recovery data were obtained by fortifying 9 matrices at 0.05–0.1 µg/g. Recoveries of 180 pesticides were mainly 70–110% and the relative standard deviation (RSD) was below 25%. Limits of detection ranged between 0.01 and 0.05 µg/g for tested pesticides. © Pesticide Science Society of Japan

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Pyrrolnitrin, produced by several bacteria that are used in biological control, has an inhibitory effect on the electron transport system of respiration in Neurospora crassa. We have previously described that fludioxonil, a derivative of phenylpyrroles, affects osmotic signal transduction. Both pyrrolnitrin and fludioxonil were highly active against Botrytis cinerea, Fusarium oxysporum, Rhizoctonia solani, and N. crassa. However, a high concentration of pyrrolnitrin (more than 10 µg/ml) inhibited the growth of fludioxonil-insensitive fungi such as Pythium ultimum, Phytophthora capsici, and Saccharomyces cerevisiae. In order to clarify the difference in the antifungal mechanisms between pyrrolnitrin and fludioxonil, we observed cross-resistance in mutants of the osmotic signal transduction pathway, namely, os-1 (histidine kinase), os-4 (MAPKK kinase), os-5 (MAPK kinase), and os-2 (MAP kinase) of N. crassa. All os mutants that were resistant to fludioxonil showed cross-resistance to pyrrolnitrin without exception. The levels of resistance to pyrrolnitrin correlated well with those to fludioxonil in the 10 os-1 mutant alleles with single amino acid substitutions. However, at a concentration of 6.1 µg/ml, pyrrolnitrin inhibited the growth of all strains including the os mutants insensitive to fludioxonil even at 25 µg/ml. When the conidia of the wild-type strain were grown on a medium containing either fungicide at a concentration of 0.1 µg/ml, both fungicides induced the swelling and rupture of conidia without germ-tube formation. At a concentration of 25 µg/ml, pyrrolnitrin inhibited conidia germination without any morphological change in the fludioxonil-insensitive os-5 mutant. Both fungicides at a concentration of 1 µg/ml stimulated glycerol synthesis in the wild-type strain, but the glycerol content was reduced to a considerable extent on treatment with 25 µg/ml pyrrolnitrin. These results suggest that a primary antifungal mechanism of pyrrolnitrin against N. crassa is interference with the osmotic signal transduction pathway rather than inhibition of respiration. © Pesticide Science Society of Japan

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A new pyrrolinone compound, methyl 1-[1-(3,5-dichlorophenyl)-1-methylethyl]-2,3-dihydro-4-methyl-2-oxo-3-phenyl-1H-pyrrole-3-carboxylate (PC-1), has herbicidal activity against early watergrass (Echinochloa oryzicola). This compound showed good selectivity between rice (Oryza sativa) and early watergrass due to the introduction of a methoxycarbonyl group into the pyrrolinone structure. To elucidate the mechanism of PC-1's phytotoxicity, the effects of esterase inhibitors (triphenyl phosphate, tributyl phosphate and fenitrothion) and a cytochrome P450 monooxygenase inhibitor (1-aminobenzotriazole) on the actions of PC-1 were examined. Triphenyl phosphate and fenitrothion reduced the phytotoxicity of PC-1 in hydroponics and greenhouse tests. Porcine liver esterase converted PC-1 to 1-[1-(3,5-dichlorophenyl)-1-methylethyl]-4-methyl-3-phenyl-3-pyrrolin-2-one (PC-2) and this reaction was inhibited by triphenyl phosphate. The PC-2 content of early watergrass treated with PC-1 was 4 times that of rice. These results suggest that PC-1 is a prodrug and is converted to PC-2 by esterase, and that the amount of PC-2 produced in PC-1-treated plants is related to the sensitivity of early watergrass and rice to PC-1. © Pesticide Science Society of Japan

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Benthiavalicarb-isopropyl, a novel member of the amino acid amide carbamate group of fungicides, is effective against all Oomycete fungal plant pathogens except Pythium spp. Our results demonstrate that this fungicide effectively controls potato and tomato late blight caused by metalaxyl-sensitive and -resistant strains of Phytophthora infestans. Experiments in vitro demonstrated that benthiavalicarb-isopropyl was ineffective in stopping the discharge of zoospores from zoosporangia and suppressing their motility; but strongly inhibited mycelial growth, sporulation, and the germination of sporangia and cystospores. Experiments in a greenhouse showed that benthiavalicarb-isopropyl has not only a strong preventive, but also a curative effect; its translaminar properties are effective along with its rainfastness and residual activity. In field trials, it was effective in controlling tomato and potato late blight at 25–75 g a.i./ha. © Pesticide Science Society of Japan

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Soil samples were obtained from 814 farms in Tokyo in 2002. Dieldrin residue was detected in 85 soil samples at concentrations ranging from 0.01 ppm to 2.6 ppm. The residual amount in 70% of dieldrin-positive samples was 0.1 ppm or less. Concentrations of dieldrin residue in cucumbers cultivated in Tokyo exceeded the tolerable level (0.02 ppm) and ranged from 0.02 ppm to 0.1 ppm in 12 of 330 samples. The horizontal distribution of dieldrin in fields was not uniform and the range varied from the quantitative limit (0.01 ppm) to 0.73 ppm. The vertical distribution of dieldrin was also inconsistent. With deeply plowed fields, the vertical distribution was from the surface to a depth of 70 cm, although dieldrin was detected at 30 cm in fields that had not been plowed. As the cucumber roots grew about 1 m in the horizontal and vertical directions, we need to analyze soil samples to a depth of 1 m to prevent dieldrin residue from contaminating cucumbers. © Pesticide Science Society of Japan

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The effects of pyridalyl and various cytotoxic substances on ATP levels in cultured Sf9 cells were compared. Levels decreased markedly after treatment with the mitochondrial respiration disruptors acequinocyl (10 µM), chlorfenapyr (1.0–10 µM), fenpyroxymate (0.01–1.0 µM), rotenone (0.1–10 µM), 2-chlorocarbonylcyanide phenylhydrazine (0.1–1.0 µM) and oligomycin (0.1–10 µM), but increased after treatment with 10 µM of anisomycin, a protein synthesis inhibitor. An RNA synthesis inhibitor, 5-fluorouracil (0.1–10 µM), did not have any effect. Pyridalyl (0.1–10 µM) reduced the ATP content of the cells; however, the rate of the decrease was not rapid. © Pesticide Science Society of Japan

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A number of 4-amino-5-aryl-2,3-dihydro-3H-1,2,4-triazole-3-thiones were synthesized and tested for inhibitory activity against trans-cinnamate 4-hydroxylase (C4H) from Populus kitakamiensis, which was expressed in yeast. Of the compounds tested, 4-amino-5-phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (1) was the most effective, having an IC₅₀ value of 0.32 µM. Replacement of the phenyl group with heterocycles or substituted phenyl groups drastically reduced the activity. Compound 1 behaved as a mixed-inhibitor of C4H. When potato tuber disks were treated with 1 (0.2–20 ng/disk) in the presence of laminarin, a β-1,3-glucooligosaccharide elicitor, trans-cinnamic acid was accumulated at levels 3 times higher than in disks treated with laminarin alone. © Pesticide Science Society of Japan

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Following a recent report of unexpectedly high affinity of 5-azidoimidacloprid to insect nicotinic acetylcholine receptor, derivatives with four halogen atoms and cyano and nitro were prepared, and the insecticidal effect was evaluated in American cockroaches by injection alone and with synergists, piperonyl butoxide and propargyl propyl benzenephosphonate. The log (1/MLD) value, the minimal lethal dose in mol, was 8.96 for imidacloprid, and 8.82 for the fluoro derivative. The other derivatives were less active. Synergists enhanced the activity of all compounds. The log (1/MLD) value for 5-azidoimidacloprid, 7.37 without or 8.18 with synergists, was not striking in this experiment. © Pesticide Science Society of Japan

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