Sub-chronic Toxicity Test of Tephrosia canadida DC. in Mice

[ Objective] To observe sub-chronic toxicity of Tephrosia canadida DC. in mice and thus to evaluate their safety to be used as protein feed resources. [ Methed]Sixty-four 6-week-old healthy Kunming mice weighing about 25 g were randomly divided into four groups （ n = 16）, half male and half female. Mass ratios of basic diet to leaf meal of Tephrosia canadida DC. in group A, group B, group C and group D were 10：0, 4：1, 3：2 and 2：3, respectively. After 35-d feeding, the effects of Tephrosia canadida DC. on growth, blood and organs of mice were observed. [ Resultl Dudng the trial, all mice had normal activities, and no death and no abnormal blood index were observed. All organs of the mice in the experimental groups had no visible pathological lesion, and organ indexes had no significant difference between the experimental groups and the control group. Except that slightly abnormal histological changes appeared in liver and kidney of the mice in the group C and D, no histological change was ob- served in other organs of the experimental mice. [ Conclusion] Tephrosia canadida DC. have no adverse effects on mice, which provides a refer- ence for research about their safety in feed of other animals.

Acute and Sub-Chronic Toxicity Evaluation of the Crude Methanolic Bark Extract of Bridelia micrantha (Hochst.) Baill. (Phyllanthaceae) and Its Fraction

Bridelia micrantha, commonly known as coastal golden leaf, is a member of the family Phyllanthaceae. In preliminary studies nine fractions, named F1 - F9, were obtained by fractionating the crude methanol extract of the stem bark of Bridelia micrantha using column chromatographic techniques. The fraction F6 was the most active when tested for antibacterial activity. Thus, toxicity of this fraction was investigated for further use. The present study evaluated the acute and sub-chronic toxicity of the crude methanolic bark extract of Bridelia micrantha and its fraction. The acute toxicity was carried out according to the experimental protocol of Organization for Economic Co-operation and Development (OECD). The plant extract or the fraction F6 was administered orally to female mice at a single dose of 2000 mg/kg and the animals were observed for any behavioral changes or mortality for 14 days. In the sub-chronic toxicity study, the extract and fraction were administered orally at 200, 400 and 800 mg/kg bw/day for 28 days to healthy Wistar rats. The general behavior and body weight of the rats were recorded daily. At the end of the experimental period, hematological and biochemical analyses, changes in vital organ weight (liver, lung, heart, spleen and kidney), and histopathological examination of the liver and kidney were performed. No mortality or adverse effects were noted at the 2000 mg/kg dose during the oral acute toxicity test. In the sub-chronic study, the crude methanolic bark extract of Bridelia micrantha and the fraction F6 induced no mortality or treatment-related adverse effects on body weight, general behavior, relative organ weights, hematological and biochemical parameters. Histopathological examination of the liver and kidney showed normal architecture suggesting no morphological alterations. In conclusion, the oral administration of the crude methanolic bark extract of Bridelia micrantha and the fraction F6 for 28 days at a dosage of up to 800 mg/kg did not induce toxicological damage in rats. From acute toxicity study, the median lethal dose (LD50) of the crude methanolic bark extract of Bridelia micrantha and the fraction F6 was estimated to be more than 2000 mg/kg.

Acute Toxicity of Jinchuan Formula Plum Wine Extract and Its Protective Effect on Mice with Liver Injury

[Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal dose(LD_(50))was determined by acute toxicity test with the toxic reaction and mortality of mice as indexes.Sixty Kunming mice were randomly divided into 6 groups:normal control group,model group(ConA-induced liver injury model),Jinchuan formula plum wine high,medium and low dose groups(1.0,0.5,0.25 g/kg)and silybin group(0.1 g/kg).The levels of ALT,AST,LDH in serum and TG,VLDL in liver were measured.After HE staining,the pathological changes of liver tissue in mice were observed,and the liver protective effect of Jinchuan formula plum wine extract was analyzed and evaluated.[Results]LD_(50)was 11.18 g/kg,and the 95%confidence limit of LD_(50)was 10.31-12.05 g/kg.The high-dose group of Jinchuan formula plum wine extract could significantly reduce the serum ALT and AST activities of ConA-induced liver injury mice(P<0.05).[Conclusions]Jinchuan formula plum wine extract is relatively safe,and also has a protective effect on liver injury.

Acute and Sub-chronic Toxicity of Indole Alkaloids Extract from Leaves of Alstonia scholaris (L.) R. Br. in Beagle Dogs

Alstonia scholaris(L.)R.Br.,an evergreen tropical plant rich in indole alkaloids with significant physiological activity,is traditionally used to treat respiratory diseases in China.This study was conducted to establish the toxicity profile of the alkaloid extract(TA)of A.scholaris leaves in non-rodents.After oral administration of a single dose(4 g/kg.bw),a num-ber of transient symptoms,such as unsteady gait,drooling,emesis,and reddening of peri-oral mucosa,were observed,but no treatment-related mortality.A sub-chronic toxicity study with a range of doses of TA(20,60 and 120 mg/kg.bw)was conducted for a 13-week treatment period,followed by 4-week recovery observation.Except for emesis and drooling in majority of animals in 120 mg/kg.bw treatment group,no clinical changes were observed in TA-treated animals.Data from electrocardiography,bone marrow,urine,fecal,hematology and clinical chemistry analyses were comparable between TA-treated and control animals.No significant differences in the relative organ weights and histopathological characteristics were evident between the TA-treated and control groups.Accordingly,the non-observed-adverse-effect-level(NOAEL)of TA was established as 120 mg/kg.bw.Our results add further knowledge to the safety database for indole alkaloid extracts from A.scholaris with potential utility as novel drug candidates.

Acute Toxicity Test of Chinese Herbal Compound Tongmai Tangyanming Capsule

[Objective] This study was conducted to determine the safe dose of Tongmai Tangyanming capsule in clinic by evaluating its acute toxicity, so as to ensure clinical medication safety. [Method] The test was designed according to ＂Technique Requirements of Research of New Chinese Medicine＂ and ＂Guide for Research of New Chinese Medicine＂, mice were intragastrically administrated with Tongmai Tangyanming capsule at a maximum concentration and a maximum volume, and the acute toxic response of mice was observed, so as to determine medi- na lethal dose （LDso） and maximum administration dosage of Tongmai Tangyanming capsule. [Result] The LD^o could not be detected in the test, and the maximum administration dosage of mouse was calculated to be 112.104 g of dried herbs/（kg.d）, equivalent to 260 times of clinical dose of adult. [Conclusion] Chinese herbal compound Tongmai Tangyanming capsule has low acute toxicity, and its clinical dose is safe and reliable.

Effects of bifenthrin on Daphnia magna during chronic toxicity test and the recovery test

The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).

Comparison of T-2 Toxin and HT-2 Toxin Distributed in the Skeletal System with That in Other Tissues of Rats by Acute Toxicity Test

Twelve healthy rats were divided into the T-2 toxin group receiving gavage of 1 mg/kg T-2 toxin and the control group receiving gavage of normal saline. Total relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system（thighbone, knee joints, and costal cartilage） were significantly higher than those in the heart, liver, and kidneys（P 〈 0.05）. The relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system（thighbone and costal cartilage） were also significantly higher than those in the heart, liver, and kidneys. The rats administered T-2 toxin showed rapid metabolism compared with that in rats administered HT-2 toxin, and the metabolic conversion rates in the different tissues were 68.20%-90.70%.

A novel respirometer for biological toxicity tests

A respirometer has been developed for microbial toxicity tests. The respirometer is based on luminescence quenching by molecular oxygen. The oxygen sensing film consists of luminescent ruthenium complex adsorbed on amorphous fumed silica and immobilized inside silicone rubber. The luminescence intensity depends on the oxygen concentration of sample in contact with sensing film. The inhibition effect of heavy metals on the respiration rate of microorganisms can be evaluated by monitoring the luminescence intensity of the sensing film. The toxicity of Cu 2+ , Zn 2+ , Ni 2+ , Cr 3+ , Pb 2+ and Hg 2+ on activated sludge was tested using the respirometer. The results indicated that the proposed method was sensitive to the heavy metals tested in this experiment. It was feasible to use the respirometer for microbial toxicity tests.

Prospects for the continued development of environmentally-realistic toxicity test susing microorganisms

The focus of environmental regulations has changed significantly since the introduction of the bioassay as a standard means of assessing environmental impact.Prominent in this change is an increasing emphasis on protecting the integrity of natural ecosystems,which incorporate community-and system-level properties as well as organismal and population processes.Consequently,support for the use of multispecies testing has widened to include not only ecologists in academia but environmental scientists in the regulatory and industrial sector as well.The reason for this trend is clear:the additional environmental realism gained from tests utilizing communities of organisms allows for greater insight into the potential hazard of chemicals and other forms of human activity to natural ecosystems that cannot be obtained from single species tests alone.Many of the problems cited for multispecies testing early in their evolution as a hazard assessment tool have been refuted or overcome.In particular,the use of natural microbial communities minimizes several shortcomings typically associated with multispecies toxicity testing.This discussion includes the utility of microcosm and mesocosm tests using aquatic microbial communities as hazard assessment tools in conjunction with accumulating information on their performance in toxicity testing protocols.An increasing body of experimental evidence supports an expansion in the use of these tests for a variety of regulatory and research purposes.A shift in research focus is needed,however,to answer remaining questions and further refine standard protocols for these valuable ecotoxicological tools.

Effects of Sub-chronic Intoxication of 1,8-cineole on Blood Biochemical Indexes of Mice

[ Objective] Effects of sub-chronic intoxication of 1,8-cineole on body weights, routine blood indexes and biochemical indexes of mice were investigated. [Method] One hundred and sixty mice with body weights of 15 -17 g were randomly divided into four groups （forty mice per group）. Mice were injected to 1, 8 - cineole with doses of 192.45,64. 15 and 21.38 mg/kg body weight （ test groups） and the water solution of tween-80 with a volume fraction of 0.5% （ control group） respectively. Each mouse was administered orally at the dose of 0.2 mL per 10 g body weight once a day consecutively for 90 d. The body weight, routine blood indexes and serum biochemical indexes of mice were determined on the 30^th d, 60^th d, 90^th d and the 30^th d after stopping the administration of 1,8-cineole. [ Result] The effects of 1, 8-cineole on the body weight, routine blood indexes and serum biochemical indexes of mice with the doses of 64.15 and 21.38 mg/kg body weight had no statistically significant difference compared with the control group （P 〉0.05 ）. 1, 8-cineole with the dose of 192.45 mg/kg body weight exhibited different influences on routine blood indexes and serum biochemical indexes of mice after the oral administration of 1,8-cineole for 60 d and 90 d, and statistically significant differences in many blood biochemical indexes were observed （P 〈 0.05 ）. However, the differences in routine blood indexes and serum biochemical indexes were not statistically significant between the test groups and the control group at the 30＇h d after stopping the administration of 1, 8-cineole （ P 〉 0.05）. [Condusion] 1,8-cineole had sub-chronic oral toxicity to mice. The no observed adverse effect level （NOAEL） of 1,8-cineolc was 64.15 mg/kg body weight and the lowest observed adverse effect level （LOAEL） of 1,8-cineole was 192.45 mg/kg body weight. Effects of 1, 8-cineole on blood biochemical indexes of mice were in short term and reversible.

Toxicity Tests of Soil Contaminated by Recycling of Scrap Plastics

The present investigation studied the toxicity of soil contaminated by untreated discharge from a factory that recycles used plastics. The nearby agricultural areas and freshwater fish ponds were polluted with high concentrations of Cu, Ni, and Mn. Water extracts from the contaminated soil retarded root growth of Brassica chinensis (Chinese white cabbage) and Cynodon dactylon (Bermuda grass) where their seeds were obtained commercially. The contaminated populations of C. dactylon, Panicum repen (panic grass), and Imperata cylindrica (wooly grass) were able to withstand higher concentrations of Cu. Ni, and Mn, especially C. dactylon, when compared with their uncontaminated counterparts. 1990 Academic Press, Inc.

Morphological Features of Agaricus bisporus and Indoor Toxicity Test of Chemicals

Through separating and purifying diseased mushrooms infected by Mycogone perniciosa in Gaochun Area, Nanjing City, morphological features of the bacteria were identified, and toxicity of the bacterial strains was tested. The results showed that five bactericides in the experiment had obvious inhibitory effect on the growth of M. perniciosa, especially 50% Prochloraz manganese chloride complex WP 5 g/L had the best efficiency.

Reply to 'Statistical testing and distribution for lead chloride toxicity'

We are very grateful for the letter written by Dr Lange,and indeed apologize for the mistakes noted in the word-ing of our text regarding statistical analysis.This wasdue to changes carried out while revising the manuscriptat the request of reviewers,whom we thank for,point-ing out several issues that were actually similar to thosenoted by Dr.Lange.Unfortunately,we were unable todescribe and discuss our findings properly in the context

Acute Toxicity Test of Miantan Fuzheng Powder

[Objectives] An acute toxicity test of Miantan Fuzheng Powder was conducted on rabbits,which were given Miantan Fuzheng Powder at its maximum administration dosage and observed for 14 d,so as to provide reference for medicine development and clinical test.[Methods] New zealand rabbits were divided into four groups randomly,each of which included 4 rabbits,half male and half female.The Miantan Fuzheng Powder-intact skin and Miantan Fuzheng Powderdamaged skin groups were applied with Miantan Fuzheng Powder once at a dose of 5 g/kg body weight,and the blank control group-intact skin and blank controldamaged skin groups were given the auxiliary material( vaseline) once.The rabbits were observed continuously for 14 d after the administration,and variation in body weight was recorded during the observation and then statistically analyzed with SPSS.After the 14 d of observation,the animals were killed through pentobarbital anesthesia and anatomized to observe main visceral organs including heart,liver,spleen lung and kidney.If toxic effect or organ abnormality exists,pathological sections would be prepared and observed.[Results] Rabbits in the blank control and Miantan Fuzheng Powder groups all showed normal appearance,behavior,breath state,position and posture,response to stimulation and growth of body weight,and no irritative erythema and edema on the skin,and the damaged skin recovered naturally within 14 d.No obvious abnormality was observed on visceral organs in autopsy.The Miantan Fuzheng Powder-intact skin and Miantan Fuzheng Powder-damaged skin groups had no significant differences in body weight from the blank control group-intact skin and blank control-damaged skin groups before administration,and on the 7^(th) and 14^(th) day after administration.[Conclusions] In this acute toxicity test,the Miantan Fuzheng Powder-intact skin and Miantan Fuzheng Powder-damaged skin groups were given the drug at the maximum administration dosage of 5 g/kg body weight,which was about 119 times of the clinical dose for human,and no obvious toxic effect was observed.

Toxicity and Field Efficacy Test of Several Insecticides against Carsidara marginalis Walker

[Objective]The paper was to study the prevention and control effect of different chemical insecticides on Carsidara marginalis Walker.[Method]The indoor toxicity and field efficacy of six insecticides against C.marginalis were determined by residual film method and field efficacy test.The toxicity and field efficacy were comparatively analyzed.[Result]The LC50 of 5%abamectin EC,24%spirotetramat EC,10%lambdacyhalothrin EC,10%nitenpyram SL,25%pymetrozine WP and 20%imidacloprid EC against C.marginalis were 3.585,12.083,15.012,18.754,23.373 and 61.161 mg/L,respectively.The field efficacies against C.marginalis at 1 d post administration were 78.04%,80.05%,69.92%,82.27%,71.72%and 76.72%,respectively.The field efficacies against C.marginalis at 10 d post administration were 92.49%,82.41%,83.80%,88.24%,94.10%and 97.01%,respectively.[Conclusion]The agents with strong quick effect and insecticides with strong systematic conductivity should be mixed together,in order to achieve quick and continuous insecticidal effects.

Sensitivity of Different Cytotoxic Responses of Vero Cells Exposed to Organic Chemical Pollutants and their Reliability in the Bio-toxicity Test of Trace Chemical Pollutants

Objective To find a sensitive cytotoxic response to reflect the bio-toxicity of trace organic pollutants, the sensitivity and reliability of morphological change and proliferation inhibition of Vero cells exposed to 2, 4, 6-trichlorophenol （TCP） and the leachate from products related to drinking water （PRDW） were compared, and the mechanism of the morphological change in Vero cells exposed to chemical pollutants was studied. Methods Vero cells were treated by different concentration of TCP and the leachate from PRDW. Methylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide （MTT） assay was carried out for proliferation inhibition. Bioluminescence method was carried out as another method to test the toxicity of TCP. Flow Cytometry assay was used to test cell Apoptosis and damage of cell-membrane. Results 0.25 mg/L TCP had an effect on cell morphology, and the proportion of morphologically changed cells increased with increasing TCP concentration. At low TCP concentrations, inhibition of cell proliferation did not seem to correlate to TCP concentration, and was negative when TCP concentration was 〈1.0 mg/L. After exposure to leachate from PRDW extracted at different temperatures, the percentage of morphologically changed cells increased with extracting temperature, but the inhibition of cell proliferation failed to reflect the correlation between extracting temperature and proliferation inhibition of Vero cells. Although the Sensitivity of bioluminescence method seems to be similar to morphological change in Veto cells, the bacterial in this method is not homologous enough with human body cells to reflect the toxicity to human body. These imply cell morphological change is a more sensitive and reliable method to reflect bio-toxicity of organic pollutants than proliferation inhibition. Flow cytometry analysis and cell rejuvenation experiments indicated cell membrane damage, which results in cell morphological change, was an early and sensitive cytotoxic response comparing with necrosis. Conelusion These results indicated that the cell membrane toxicity represented by morphological changes is a more sensitive and reliable method to indicate the composite bio-toxicity of trace chemicals than proliferation inhibition, inhibition on bioluminescence and necrosis. Nevertheless, the quantification of morphological change should be studied further.

Screening of Field Efficacy of Special Pesticides for Mulberry and Residual Toxicity of Silkworm

[Objective] The paper was to screen the pesticides with good control effects against pests in mulberry and small impact on silkworm. [Method] The combined method of indoor toxicity test, field efficacy test, fast testing of pesticide residues and residual toxicity determination were adopted to carry out test. [ Re- suit] Indoor toxicity results showed that LC50 of mulberry No. 1 against Hyalopterus amygdale was （316.1±57.3） mg/kg, and the control effect of mulberry No. 1 at 14 d reached 62.58% ; fast testing of pesticide residues at 7 d showed that the mulberry leaves were safe to silkworms, which reached the standard of leaves for silkworm. [ Conclusion] Mulberry No. 1 was recommended to be the Special pesticide to apply in mulberry field.

Preparation and toxicity evaluation of a novel nattokinase-tauroursodeoxycholate complex

Nattokinase(NK), which has been identified as a potent fibrinolytic protease, has remarkable potential in treatment of thrombolysis, and even has the ability to ameliorate chronic vein thrombosis. To reduce the hemorrhagic risk from an intravenous injection of NK,nattokinase-tauroursodeoxycholate(NK-TUDCA) complex was prepared at different pH values and with different ratios of NK and TUDCA. When assessing survival time, survival state,tail injury, and the body weight of mice, it was found that the NK-TUDCA complex(NK: 10 k IU/ml; TUDCA: 10 mg/ml; pH 5.0) had a lower toxicity when administered at an NK dosage of 130 kIU/kg in the acute toxicity test and 13 kIU/kg in the repeated low-dose challenge. From the results of the in vitro thrombolytic test and characterization of NKTUDCA, we speculated that the delayed release of NK-TUDCA might be the main cause of toxicity reduction by the complex. This study described the preparation of an NK complex with low toxicity following intravenous administration, which could be utilized for further clinical study of NK.

Evaluating the safety of forsythin from Forsythia suspensa leaves by acute and sub-chronic oral administration in rodent models

Objective: To access the toxicity of forsythin from Forsythia suspensa leaves and evaluate its safety,Methods: Acute toxicity was determined by oral administration of a single dose of 18 100 mg/kg forsythin in NIH mice,Sub-chronic toxicity was evaluated by oral administration of several doses of forsythin for 30 days at does of 0,540,1 620,and 6 480 mg/kg in SD rats.Results: In the acute toxicity study,mortality was not observed after 14 days,In addition,clinically relevant adverse effects,or variations in body weight or food consumption were not observed,Similarly,after 30 days in the sub-chronic toxicity study,no mortality or significant toxicological effects such as decreased food consumption,body weight,biochemical parameters and vital organs etc,were noticed,Conclusion: The results revealed that the forsythin from Forsythia suspensa leaves has low or no toxicity via oral administration,and therefore is suitable for further development and applications.

Subchronic Oral Toxicity Evaluation of Lanthanum： A 90-day, Repeated Dose Study in Rats

Objective The present study was undertaken to evaluate the subchronic toxicity of lanthanum and to determine the no observed adverse effect level（NOAEL）,which is a critical factor in the establishment of an acceptable dietary intake（ADI）.Methods In accordance with the Organization for Economic Co-operation and Development（OECD） testing guidelines,lanthanum nitrate was administered once daily by gavage to Sprague-Dawley（SD） rats at dose levels of 0,1.5,6.0,24.0,and 144.0 mg/kg body weight（BW） per day for 90 days,followed by a recovery period of 4 weeks in the 144.0 mg/kg BW per day and normal control groups.Outcome parameters were mortality,clinical symptoms,body and organ weights,serum chemistry,and food consumption,as well as ophthalmic,urinary,hematologic,and histopathologic indicators.The benchmark dose（BMD） approach was applied to estimate a point of departure for the hazard risk assessment of lanthanum.Results Significant decreases were found in the 144.0 mg/kg BW group in the growth index,including body weight,organ weights,and food consumption.This study suggests that the NOAEL of lanthanum nitrate is 24.0 mg/kg BW per day.Importantly,the 95% lower confidence value of the benchmark dose（BMDL） was estimated as 9.4 mg/kg BW per day in females and 19.3 mg/kg BW per day in males.Conclusion The present subchronic oral exposure toxicity study may provide scientific data for the risk assessment of lanthanum and other rare earth elements（REEs）.