Use of Acute Toxicity Data in the Design and Interpretation of Subchronic and Chronic Toxicity Studies

1993 ◽  
pp. 39-48
Author(s):  
Karl K. Rozman
Keyword(s):  
Acute Toxicity ◽  
Chronic Toxicity ◽  
Toxicity Data ◽  
Toxicity Studies

scholarly journals Toxic Effects of Cannabis and Cannabinoids: Animal Data

2005 ◽  
Vol 10 (suppl a) ◽  
pp. 23A-26A ◽  
Author(s):  
Pierre Beaulieu
Keyword(s):  
Acute Toxicity ◽  
Present Article ◽  
Chronic Toxicity ◽  
Toxic Effects ◽  
Acute Administration ◽  
Toxicity Data ◽  
Toxicity Studies ◽  
Animal Data ◽  
Animal Toxicity

The present article reviews the main toxic effects of cannabis and cannabinoids in animals. Toxic effects can be separated into acute and chronic classifications. Acute toxicity studies show that it is virtually impossible to die from acute administration of marijuana or tetrahydrocannabinol, the main psychoactive component of cannabis. Chronic toxicity involves lesions of airway and lung tissues, as well as problems of neurotoxicity, tolerance and dependence, and dysregulations in the immune and hormonal systems. Animal toxicity data, however, are difficult to extrapolate to humans.

scholarly journals ACUTE AND SUB CHRONIC TOXICITY STUDIES OF PURIFIED WITHANIA SOMNIFERA EXTRACT IN RATS

2018 ◽  
Vol 10 (12) ◽  
pp. 41 ◽  
Author(s):  
Benny Antony ◽  
Merina Benny ◽  
Binu T. Kuruvilla ◽  
Nishant Kumar Gupta ◽  
Anu Sebastian ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Dose Level ◽  
Chronic Toxicity ◽  
Withania Somnifera ◽  
Clinical Signs ◽  
Repeated Administration ◽  
Female Rats ◽  
Toxic Effects ◽  
Toxicity Studies ◽  
Adverse Effect Level

Objective: The objective of the present study was to evaluate the acute and sub-chronic (90 d; repeated dose) toxicity of Withania somnifera (ashwagandha) extract in rats.Methods: The acute toxicity was evaluated as per OECD (Organisation for Economic Co-operation and Development) guidelines 423. Purified ashwagandha extract (PAE) was fed at 2000 mg/kg body weight (bw) to overnight fasted female rats. The animals were observed daily for clinical signs of abnormality/mortality. After 14 d, animals were sacrificed and gross pathological changes were recorded. Sub-chronic toxicity of PAE was studied by feeding the extract at 100, 500 and 1000 mg/kg bw daily to rats as per OECD guidelines 408. After 90 d feeding, heamatological and biochemical parameters of treated rats were compared with control animals. Histopathology of all the major organs was also studied.Results: In the acute toxicity study, no mortality or clinical signs of toxicity were observed in any of the animals at maximum recommended dose level of 2000 mg/kg bw; therefore the LD50 is>2000 mg/kg bw in rats. The repeated administration of PAE for 90 d in rats at the maximum dose level of 1000 mg/kg bw did not induce any observable toxic effects, when compared to its corresponding control animals. The hematology and biochemistry profile of treated rats was similar to control animals and difference was non-significant (p>0.05). The histopathology of major organs of all the control and treated animals was normal. In this study the NOAEL (No Observed Adverse Effect Level) was calculated as 1000 mg/kg bw daily for rats.Conclusion: The present study clearly indicates that PAE does not have any toxic effects in animals at the dose evaluated as evidenced by acute and sub chronic toxicity studies in rats.

Development of an Acceptable Factor To Estimate Chronic End Points From Acute Toxicity Data

1985 ◽  
Vol 1 (4) ◽  
pp. 261-269 ◽  
Author(s):  
Bradly C. Venman ◽  
Christine Flaga
Keyword(s):  
Acute Toxicity ◽  
Chronic Toxicity ◽  
Daily Intake ◽  
Toxicity Data ◽  
Acceptable Daily Intake ◽  
End Points ◽  
Uncertainty Factors ◽  
Daily Exposure

Acceptable daily intake (ADI) values are routinely developed for threshold toxicants from NOAELs determined from human or animal chronic or subchronic data. These NOAELs are then divided by appropriate uncertainty factors ranging from 10 to 1000 depending on the quality of the data. However, for the vast majority of chemicals used industrially, adequate toxicity data needed to use this process are not available. Thus, a procedure to estimate a chronic toxicity endpoint from acute toxicity data, such as an oral rat LD50, becomes necessary. An acute-to-chronic application factor of 0.0001 was developed, which when multiplied by an oral LD50 for an individual chemical, yields a surrogate chronic NOAEL. This figure can then be used to estimate an acceptable daily exposure for humans. The process used to estimate this application factor is detailed.

Acute and chronic toxicity studies on Polygonum glabrum in experimental animals

2020 ◽  
Vol 3 (1) ◽  
pp. 7-10
Author(s):  
Saravanakumar A ◽  
Gandhimathi R
Keyword(s):  
Chronic Toxicity ◽  
Clinical Stage ◽  
Herbal Medicines ◽  
Plant Roots ◽  
Root Extract ◽  
Experimental Animals ◽  
Toxicity Studies ◽  
Acute And Chronic Toxicity ◽  
Diuretic Agents

Polygonum glabrum is being used in traditional and folklore medicine to treat pneumonia and jaundice. Plant roots are used in ayurvedic preparations to treat fever and colic. The leaves are used as diuretic agents and process vermifuge action. Plant decoction is also used in the treatment of Rheumatism. Besides having many uses and folklore claims, herbal medicines are to be thoroughly investigated for their toxicity also. Therefore this work is being carried out to examine the toxicity of the drug and established dose is safe to use in the clinical stage. The current research studied the acute and chronic toxicity of Polygonum glabrum root extract in rats. It is proved that there was no change in any parameter tested both in acute and chronic toxicity, which means the extract is safe and non-toxic at the dose of 2g/kg also.

Survey for Tributyltin in Water and Sediment in Canada in 1999

2005 ◽  
Vol 40 (4) ◽  
pp. 431-447 ◽  
Author(s):  
R. James Maguire ◽  
Suzanne P. Batchelor
Keyword(s):  
Acute Toxicity ◽  
Pest Control ◽  
Marine Sediments ◽  
Chronic Toxicity ◽  
Aquatic Organisms ◽  
Benthic Organisms ◽  
Freshwater Sediments ◽  
Antifouling Paints ◽  
Water And Sediment ◽  
Small Craft

Abstract A survey of water and sediment from 152 harbours, marinas and shipping channels across Canada was conducted in 1999 to determine the extent of contamination by tributyltin (TBT) prior to the total ban on its antifouling uses being phased in over the period 2003 to 2008, and to assess the effectiveness of the 1989 regulation of antifouling uses of TBT under the Canadian Pest Control Products Act. TBT was found in sediments in this survey much more frequently than in water. The main conclusion was that by 1999 the regulation had been generally effective in reducing TBT contamination in water, but not sediment, in small-craft marinas and harbours. TBT continued to be found in some freshwater and seawater locations frequented by larger vessels, that could have been legally painted at the time with TBT antifouling paints, at concentrations that could cause chronic toxicity to aquatic organisms. TBT was also found in many marine sediments, and some freshwater sediments, at concentrations that could cause chronic toxicity to sensitive benthic organisms. In addition, TBT concentrations in many marine sediments could cause acute toxicity to sensitive benthic organisms. Because of the long persistence of TBT in sediments, it may pose a hazard to benthic organisms in some locations in Canada for many years after the total ban on antifouling uses of TBT.

Effects of atrazine and alachlor on self-purification processes in receiving streams

1996 ◽  
Vol 33 (6) ◽  
pp. 181-187 ◽  
Author(s):  
Jana Zagorc-Koncan
Keyword(s):  
Adverse Effect ◽  
Acute Toxicity ◽  
Toxicity Test ◽  
Chronic Toxicity ◽  
Acute Toxicity Test ◽  
Organic Substances ◽  
Inhibiting Effect ◽  
Scenedesmus Subspicatus ◽  
Net Assimilation ◽  
Chlorophyll A Content

In recent years many waterways in Slovenia have been subjected to an increased loading with pesticides due to intensification of agriculture. The most widely used herbicides are atrazine and alachlor and they were detected in some rivers and even in ground water. Therefore the effects of atrazine and alachlor on selfpurification processes were investigated. The basic selfpurification processes studied were biodegradation of organic substances and photosynthesis and growth of algae. The inhibiting effect of pesticides on the process of biodegradation of organic pollutants was evaluated by the use of laboratory river model and mathematical modelling. The harmful impacts of pesticides on aquatic autotrophic organisms were assessed by measurement of net assimilation inhibition (24-h acute toxicity test) as well as growth inhibition - chlorophyll- a content (72-h chronic toxicity test) of algae Scenedesmus subspicatus. The results obtained demonstrate that atrazine and alachlor in concentrations found in our rivers have practically no effect on biodegrading heterotrophic organisms, while their adverse effect on algae is quite considerable.

Acute and subacute toxicity assessment of Madhulai Manappagu (Siddha herbal syrup formulation) in animal model

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Meenakshi Sundaram Malayappan ◽  
Gayathri Natarajan ◽  
Logamanian Mockaiyathevar ◽  
Meenakumari Ramasamy
Keyword(s):  
Body Weight ◽  
Acute Toxicity ◽  
Oral Route ◽  
Toxicity Assessment ◽  
Toxicity Study ◽  
Female Rats ◽  
Albino Rats ◽  
Oral Toxicity ◽  
Gross Pathology ◽  
Toxicity Studies

Abstract Objectives Madhulai Manappagu – a well-known sastric and widely prescribed Siddha herbal syrup formulation indicated for treating Veluppu Noi (Anaemia especially Iron deficiency Anaemia) has been in day today practice in Tamil Nadu for a quite longer decades. The syrup is a herbal preparation which has a sweet pleasant odour and a palatable taste, contain the juice of pomegranate (Punica granatum L.) as the main ingredient. Though the formulation is a fruit juice, the safety profile of the syrup is not established and is being marketed without toxicological evaluation. The study is aimed at ascertaining the acute and sub-acute toxicity assessment of Madhulai Manappagu in Wistar Albino rats. Methods The acute and sub-acute (28day repeated oral) toxicity studies were performed as per the guidelines mentioned in the Organization for Economic Cooperation and Development (OECD) 423 (adopted on December 2001) and TG 407 (adopted on October 2008) with slight modifications respectively. For acute toxicity study, three female rats were randomly selected as control; three female rats were randomly selected and were administered a single dose of 5,000 mg/kg body weight per oral route. For sub-acute (28day repeated oral) toxicity studies, three doses of test drug MM of 500 mg/kg/day (low dose), 750 mg/kg/day (intermittent dose) and 1,000 mg/kg/day (high dose) were selected for administration. Both sexes of Wistar Albino rats were randomized into four groups of 10 animals each (five males, five females). Group I was kept as control group. Group II, III and IV served as low, intermittent and high doses of MM respectively. Animals were observed for mortality, morbidity, body weight changes, feed and water intake. Haematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight and histopathological examination were performed. Results In the acute toxicity study, rats showed no toxicological signs on behavior, gross pathology and body weight of rats when treated with a single dose of 5,000 mg/kg body weight per oral route. In the subacute (28 days repeated oral) toxicity study, rats have showed no significant changes on behavior, gross pathology, body weight, and hematological and biochemical parameters when treated with Madhulai Manappagu in three different doses. Conclusions The toxicity studies which include both acute and 28 days repeated (subacute) oral toxicity studies, revealed no observed adverse effect level (NOAEL) of Madhulai Manappagu in animals. Thus the safety of the drug in human usage was ensured.

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