• Toxicological Research
• /
• v.12 no.2
• /
• pp.143-154
• /
• 1996

This paper reviews the toxicological role of median lethal dose ($LD_50$) based on animal and human data. Animal oral $LD_50$ values of eighty seven chemicals were collected and comparatively evaluated with human minimum toxic dose ($TD_50$). In general, animal $LD_50$ values were much higher than human $TD_50$. The ratios between $LD_50$ and TDlo were ranged from 0.01 and over 1000, suggesting safety factor of up to 1000 between humans and animals in the case of acute toxicity data. However, about 40% of chemicals investigated were within the ratio of 10. Although the cases (N=20) were small, $LD_50$ values of guinea pig were closer to human TDlo than those of other animal species. In interanimal species (rat, mouse, rabbit, dog), the ratios of $LD_50$ values were between 0.1 and 5 (up to 50-fold difference). When the data are analyzed by chemical strut-ares, human $TD_50$ values were very close to rat oral $LD_50$ values. These data suggest that rat oral $LD_50$ value might be a useful parameter predicting human TDlo and one animal species could be sufficient for acute toxicity test.

• Toxicological Research
• /
• v.20 no.4
• /
• pp.321-324
• /
• 2004

Lethal dose 50% ($LD_{50}$) has been commonly used as a parameter for the estimation of acute toxicity not only in animal experiment, but also in human study. Several methods to estimate $LD_{50}$ had been introduced, but Spearman-Karber and Berens-Karber method have been widely used due to their relative convenience and accuracy. However, $LD_{50}$ values estimated from the two methods showed inconsistency and variation depending on the characteristics of mortality data. In this study, the two methods were comparatively investigated in terms of accuracy and stability for the estimation of $LD_{50}$.

• BMB Reports
• /
• v.36 no.5
• /
• pp.499-504
• /
• 2003

There has been increasing interest in studying the various effects of organophosphate insecticides in humans and experimental animals. Only a few data are available on the effect of the organophosphate insecticide, diazinon, on lipid metabolism. The aim of this study was to evaluate the effect of diazinon on plasma lipid constituents in mammalian animals. The plasma levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and phospholipids (PL) were measured in albino rats that were orally treated with a single dose of diazinon at a level of $LD_{50}$ or with repeated daily doses at the levels of $\frac{1}{2}$, $\frac{1}{8}$, and $\frac{1}{32}$ $LD_{50}$ for 2, 8, and 32 days, respectively. After a 24 h post-treatment with a single $LD_{50}$ dose of diazinon, TC was not significantly changed, the HDL-C and PL levels were significantly decreased, but the LDL-C and TG levels were significantly increased. Separate daily oral administrations of diazinon at $\frac{1}{2}$ $LD_{50}$, $\frac{1}{8}$ $LD_{50}$, and $\frac{1}{32}$ $LD_{50}$ doses resulted in a significant decrease in HDL-C and PL, with no significant change in TG. The LDL-C levels were significantly increased and TC showed no significant change with $\frac{1}{2}$ $LD_{50}$ and $\frac{1}{32}$$LD_{50}$ doses of diazinon, whereas a significant decrease in the levels of TC, HDL-C, as well as LDL-C, was observed with the $\frac{1}{8}$ $LD_{50}$ dose. These data suggest that diazinon may interfere with lipid metabolism in mammals.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.1
• /
• pp.80-84
• /
• 2000

To investigate the effect of packaging condition on functional MA films laminated (30CE, 50CE), corrugated paperboard box (control), 30LDPE, and 50LDPE pouches on the freshness extension of Fuji apples, the weight loss, firmness, total ascorbic acid, titratable acidity, soluble solids content and appearence were evaluated at 5$^{\circ}C$ after 75 days. Weight loss of 30CE and 50CE, and 30LD and 50LD was 0.4 to 0.5%, and 0.2%, but control was 2.7%. Firmness in film packages was higher than that of control, and CE packagings were higher than LD. Total ascorbic acid content of Fuji apple in control after 75 days was 2.12 mg%, that of control was decreased by 42%, those of LD packagings were 31% and 29%, and those of CE were 24% and 22%. Titratable acidity and soluble solids content in control changed more than that of MA film packagings. Overall appearence of 'Fuji' apples in CE packagings was better than that of control.

• Korean journal of applied entomology
• /
• v.19 no.2 s.43
• /
• pp.79-83
• /
• 1980

The toxicities of some soil insecticides were evaluated in terms of the tolerance to various larval-ins tars of the common cutworm (Agrotis fucosa Butler) using topical application method in the laboratory. $LD_{50}$ values(ug/larva) were determined by the probit analysis and the tolerance-values were obtained with '$LD_{50}$ values for from 2nd-to 6th-instars/$LD_{50}$ values for first-instars.' The relative toxicities of the insecticides were 31so compared with the $LD_{50}$ values for the instars. The degree of tolerance was greatly increased as the larval instar advanced; the ranges of tolerance between the first-and 6th-instar larvae to the insecticides phoxim (Volaton), diazinon, chlorpyrifos (Dursban), carbofuran (Curaterr) and Mocap were 251.6, 126.6, 97.5, 44.3, and 18.7 times, respectively. The average relative toxicities of the insecticides for the instars indicated that the toxicity of phoxim was the greatest and following carbofuran, chlorpyrifos, Mocap and diazinon.

• Korean journal of applied entomology
• /
• v.23 no.3 s.60
• /
• pp.172-176
• /
• 1984

The insecticides MIPC, BPMC, carbofuran and diazinon were treated to the brown planthopper (BPH) , Nilaparvata lugens STAL, at the dose levels of $LD_{10}\;and\;LD_{50}$(by topical application)/at the rate of 40kg/ha (product base) (by dusting or broadcasting on potted rice). The BPH population in the first generation was significantly decreased in the topical treatments compared to the untreatment. The number of BPH offsprings was relatively greater at the dose level of $LD_{10}\;than\;of\;LD_{50}$. The number of nymphs, however, were greatly varied with the insecticides. The offsprings from the BPH treated with the rate of 40kg/ha showed longer nymphal periods and higher adult emergence, but except diazinon treatment, rather less egg-numbers were observed. The BPH population density was significantly decreased in general up to 38 days after treatment(DAT) in the treated pots. Among the insecticides tested, however, only diazinon induced greater number of insects at the 54 DAT compared to the untreated pots.

• Journal of Pharmacopuncture
• /
• v.8 no.1
• /
• pp.41-44
• /
• 2005

Objectives : This experiment was conducted to reevaluate $LD_{50}$ of Korean bee venom acupuncture as many changes have occurred over the years. Methods : ICR mice were used as the experiment animals and bee venom acupuncture was manufactured under the protocols of Korean Institute of herbal Acupuncture. Based on the previous reports, experiment was divided into pre and main sections. Results : 1. Presumed $LD_{50}$ value is at 5.25mg/kg 2. Deaths of experiment animals occurred within 48 hours. 3. Reduced toxicity of the bee venom acupuncture is likely to be the results of more refined manufacturing process and production. Conclusion : Comparing with the values of the previous results, toxicity of the bee venom acupuncture showed significant changes and more accurate findings on $LD_{50}$ value must be accomplished to lead further studies on the bee venom acupuncture.

• The Korean Journal of Pesticide Science
• /
• v.12 no.2
• /
• pp.141-147
• /
• 2008

Globally Harmonized System (GHS) for classification and labelling will provide an internationally agreed hazard classification system of chemical products and for communication of those hazards. This study aimed for establishment of the oral acute toxic class (ATC) method and application of GHS on pesticides. The ATC method was developed for determining $LD_{50}$ estimates of chemical substances with significantly fewer animals than needed when applying conventional $LD_{50}$ tests. We carried out $LD_{50}$ test and ATC test on 13 pesticides, Although methidathion EC and parathion-ethyl EC showed significantly different in $LD_{50}$ values between $LD_{50}$ test and ATC method, there are no difference in toxicity class by GHS. Both tests on the other pesticides showed almost equal results and toxicity class by GHS. Therefore, this study indicated high possibility of application of ATC method and GHS on pesticides.

• The Korean Journal of Pesticide Science
• /
• v.17 no.4
• /
• pp.473-477
• /
• 2013

This study was performed to evaluate the acute contact and oral toxicity of plant extracts (neem, sophora and derris) against Honeybee (Apis mellifera L.). As a result of acute contact toxicity test, $LD_{50}$ of neem and derris extracts were more than 100 ${\mu}g/bee$ while $LD_{50}$ of sophora extracts were 1.7 ${\mu}g/bee$. In case of acute oral toxicity test, $LD_{50}$ of neem and derris extracts were more than 100 ${\mu}g/bee$ while $LD_{50}$ of sophora extracts were 1.7 and 0.3 ${\mu}g/bee$. In conclusion, it is evaluated that neem and derris extracts are practically nontoxic while sophora extracts are highly toxic.

• YAKHAK HOEJI
• /
• v.39 no.2
• /
• pp.137-140
• /
• 1995

Saponin isolated from Sapindus mukorossi Gaertn has been shown to contain a strong anti-inflammatory activity. In this study, several pharmacological properties such as acute toxicity, local irritation and hemolytic activity of Sapindus saponin and its genin component, hederagenirl, were examined. The acute toxicity of Sapindus saponin was very low. Estimated from the LD$_{50}$ values, it showed much weaker toxicity in oral administration than in intraperitoneal injection. Hederagenin gave a very high LD$_{50}$ value even in intraperitoneal injection. Sapindus saponin showed a potent local irritation after topical application, whereas hederagenin did a very weak local irritation. Sapindus saponin also gave a high hemolytic activity.