Uptake of36Cl-toxaphene in mosquito fish,Gambusia affinis

Summary The toxicity syndrome of toxaphene to G.affinis was divided into 5 stages, and the residue level at each stage was determined. By the time fish were exhibiting the first toxicity response (stage 2), 90.3% of the mean fatal residue level had been sorbed. Regression analysis indicated that sorption of toxaphene is a linear function with respect to time. Excretion was not observed following an 8 hour exposure to 2ppm toxaphene. Metabolic alteration of toxaphene during the experiments appeared to be minimal. Differences in individual mortality-appeared to be due to differences in uptake rather than differences in ability to tolerate particular body loads of toxaphene.     

Fate of36Cl-toxaphene in rats

Summary In the rat, 52.6%, of an oral dose of³⁶Cl-toxaphene was excreted within 9 days. Approximately 37% was found in the feces and 15%, in the urine. Upon extraction, most of the radioactivity occurred in the water fractions of urine and feces as ionic chloride. Animals given a second dose on the 9th day excreted toxaphene in a similar manner except³⁶Cl excretion in feces was reduced. Less than 10% of the dose was found in selected tissues and organs 1 day following the treatment.     

Cross-resistance in insecticide-resistant strains of the German cockroach, Blattella germanica (L.)

The authors describe a series of experiments designed to determine the extent to which cross-resistance exists in insecticide-resistant strains of the German cockroach. The tests were conducted by exposing females from a DDT-resistant strain, a chlordane-resistant strain, and a non-resistant strain to varying concentrations of several insecticides. From these tests mortality data were obtained and are presented in the form of regression lines.     

Genetics and linkage of aldrin resistance in the German cockroach, Blattella germanica (L.)

The inheritance mechanism and linkage association of cyclodiene resistance were studied in 2 cyclodiene-resistant strains of the German cockroach. The resistant strains were crossed to each other, to an unmarked susceptible strain, and to 6 susceptible marker strains. The progeny from succeeding generations were tested for resistance to aldrin using a dipping method or a time-exposure method, and were examined for markers in linkage tests. The results show that cyclodiene resistance (R-Cyclo) is inherited as a simple autosomal semidominant trait which is allelic in the 2 resistant strains. Linkage studies indicate that R-Cyclo is independent of linkage groups II—VI, but is linked with the group VII trait curly wing at a distance of 3.4±1.0-6.2±1.4.     

Content of some heavy metal ions in various developmental stages of the social wasp,Dolichovespula saxonica (Fabr.) (Hymenoptera,Vespidae)

Bulletin of Environmental Contamination and Toxicology -     

Evaluation of Mercury Uptake and Distribution in Rice (Oryza sativa L.)

Bulletin of Environmental Contamination and Toxicology - Mercury (Hg) contamination in soil-rice systems from industry, mining and agriculture has received increasing attention recently in China....     

保幼激素和蜕皮激素对德国小蠊聚集信息素生物合成的影响

目的研究保幼激素和蜕皮激素对德国小蠊聚集信息素生物合成的影响，为制定德国小蠊的防制措施提供科学依据。方法提取德国小蠊聚集信息素，用气相色谱检测各组分的相对含量。结果德国小蠊在5龄前期摘除咽侧体，聚集信息素的2种主要组分二甲基二十九碳烷和甲基二十九碳烷的含量分别降低了10％和21％，注射保幼激素Ⅲ，2种组分的含量分别上升了32％和24％，而在5龄后期影响不明显；德国小蠊在5龄前期摘除前胸腺和注射20-羟基蜕皮酮（20-E），影响不显著，而在5龄后期摘除前胸腺，2种组分的含量分别降低了18％和12％，注射20-E后，则分别升高了26％和36％。结论保幼激素和蜕皮激素分别在德国小蠊5龄的前期和后期参与了聚集信息素生物合成的调控。     

Uptake, effects, and metabolism of cyanobacterial toxins in the emergent reed plant Phragmites australis (cav.) trin. ex steud

The commonly occurring cyanobacterial toxin microcystin-LR (MC-LR) was rapidly taken up by the emergent reed plant Phragmites australis with clear distribution in the different cormus parts of the plant. Highest uptake was detected in the stem, followed by the rhizome. Enzyme extracts of the rhizome system, the stem, and the leaf revealed the presence of soluble glutathione S-transferases (sGST) measured with the model substrate 1-chloro-2,4-dinitrobenzene. A significant elevation of sGST activity in the rhizome and stem parts of P. australis was detected after a 24-h exposure to 0.5 microg/L MC-LR. Rhizome, stem, and leaf tissues were also able to conjugate several microcystin toxins. However, no conjugation, either chemical nor enzymatic, was detected using the related cyanobacterial toxin nodularin as substrate. Highest glutathione S-transferase activity for the toxin substrates was detected in the pkat/mg range in the stem of P. australis. For MC-LR, a complete metabolism from the formation of a glutathione conjugate to the degradation of a cysteine conjugate in all cormus parts of the plant is reported. The stepwise degradation of the MC-LR-glutathione conjugate to a gamma-glutamylcysteine and a cysteine conjugate was demonstrated by comparison with chemically formed reference compounds and by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This is the first evidence for the uptake and metabolism of cyanobacterial toxins by an emergent aquatic macrophyte.     

Microbial Reduction of 9-Fluorenone to 9-Hydroxyfluorene in Carbon-Filtered Water: A Confounding Factor in an Aquatic Bioassay of 9-Fluorenone with Larvae of the Midge, Chironomus tentans (Fabr.)

No abstract available.     

Toxicity of metabolites of dieldrin,photodieldrin, and endrin in the cockroach

Major metabolic products of dieldrin, endrin, and photodieldrin were identified in the American cockroach, and their toxicities were tested in the male German cockroach. Among dieldrin metabolites tested, F-1 the major fecal metabolite in rats, was most toxic to the German cockroach. The most toxic metabolite of endrin was 3-hydroxyendrin. The toxic endrin metabolite to the rat, 12-ketoendrin, was not so toxic to the German cockroach. The most consistent major metabolic product of photodieldrin, U-1, which is identical to the major urinary metabolite in the rat, was less toxic and slower-acting than photodieldrin against the German cockroach, indicating that this major metabolic product is not the actual toxicant in this species.     

江苏省句容市蜚蠊密度监测及侵害现状分析

据报道,目前北京市45%以上的家庭,86%的医院,98%的宾馆、饭店已被蜚蠊入侵[1]。随着城市化进程的加快,旅游、贸易和运输的快速发展,生态环境的不断改变,蜚蠊的密度和分布正在发生新的变化,危害也日益严重。根据《全国病媒生物监测方案（试行）》,我们对句容市蜚蠊密度及其侵害现状进行了调查,以期为病媒生物传染病的预防与控制提供科学依据。     

四川省汉源县蜚蠊种群构成

蜚蠊（Blatta）是蟑螂的学名。5．12大地震之前汉源县未开展过蜚蠊种群调查,为防止灾后因病媒生物所引发的疾病流行,确保大灾之后不发生大疫的目的,在蜚蠊孳生繁殖活动高峰7月～8月与支援抗震救灾的湖北省疾病预防控制中心人员联合,开展了蜚蠊种群调查,现将调查结果报道如下：