• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.1-8
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• 2003

The development of environmentally nontoxic or non-polluting antifouling additives that can be formulated in practical coating requires assay involving target organisms. Described here are the simple laboratory assays that have been developed using the barnacle, Balanus amphitrite, a common fouling organism found throughout temperate and tropical seas. One of the assays depends on synchronous year-round mass culture, the procedure for which is described, of nauplii larvae and cyprids larvae. The laboratory assays provided quantitative estimates of toxicity and settlement inhibition of the test compounds. Laurinterol (1), isolaurinterol (2), alpysinal (3), and aplysin (4) have been isolated from the Korean red alga Laurencia okamurae. Their structures were identified by spectral data in comparison with the literature data. Compounds 1-4 inhibited larval settlement of the barnacle B. amphitrite with EC$_{50}$ values of 0.18- 36 $\mu\textrm{g}$/ml. Com-pounds 2-4 showed larval toxicity against nauplii of the barnacle B. amphitrite with 5-10 $\mu\textrm{g}$/ml, while laurinterol (1) exhibited no toxicity at even 100 $\mu\textrm{g}$/ml. Therefore, laurinterol was expected as a promising natural antifoulant.t.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.265-268
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• 2004

Larva of Carassius auratus and Pungtungia herzi were exposed to mercury ($HgCl_2$), lead ($PbCl_2$) and copper ($CuSO_4$) to determine acute toxicity. The toxicity tests were conducted triplicate and the $LC_{50}$ values (24, 48, 72 and 96 hours) were determined for two species. Data obtained from the toxicity tests were evaluated using the probit analysis. Although sensitivities of two species to mercury were relatively similar, C. auratus was more susceptible than P. herzi to the exposure of lead but P. herzi was more sensitive than C. auratus on copper. The sensitivity on three metals tested may be ranked in the following order from highest to lowest toxicity on larval stage of these fish: mercury > copper > lead. It is suggested that acute toxic test at the larval stage of C. auratus and P. herzi, indigenous species in Asia area, is an important part of the ecotoxicological assessment of some heavy metals.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.241-246
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• 2016

BACKGROUND: Recently, the widespread distribution of pesticides in the hive has been of concern about pesticide exposure on honeybee (Apis mellifera L.) health. Larval toxicity was adapted to assess the synergistic and antagonistic interaction of cumulative mortality to the honeybee larvae of the four most common pesticides detected in pollen. METHODS AND RESULTS: Acetamiprid($3.0{\mu}l/L$), chlorothalonil ($803.0{\mu}l/L$), coumaphos ($128.0{\mu}l/L$), and tau-fluvalinate ($123.0{\mu}l/L$) were tested in combination; binary, ternary and four component mixture. Larvae were exposed to four pesticides mixed in diet at the average levels detected in pollen. As a result, synthetic toxicity was observed in the binary mixture of acetamiprid with coumaphos. The binary and ternary component mixtures of tested pesticides have mostly demonstrated additive effect in larval bees. The significant antagonistic effects were found in four parings of mixtures including chlorothalonil added to acetamiprid/tau-fluvalinate or acetamiprid/coumaphos/tau-fluvalinate, and tau-fluvalinate added to acetamiprid/chlorothalonil or acetamiprid/coumaphos/chlorothalonil. CONCLUSION: Interactions between combinations of four pesticides showed mostly additive or antagonistic effects in larval bees. Therefore, predicting the larval mortality of pesticides mixtures on the basis of the results of single pesticide may actually overestimate the risk. We suggest that pesticide mixture in pollen be evaluated by adding their toxicity together for complete data on interactions.

• Animal cells and systems
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• v.7 no.4
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• pp.345-348
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• 2003

The effects of acute acid stress on hatching success and hatching period of laboratory-reared hermaphroditic fish Rivulus marmoratus were examined. The effects of acute acid toxicity on mortality was also determined in three life stages of this fish. There was a significant negative effect of acid stress on hatching performance in the R. marmoratus embryos. The hatching success was only 5% at pH 3.5 compared to over 78% at pH higher than 4.0. The hatching period was also delayed by low pH treatments. The larval and juvenile stages were more sensitive to acid toxicity on mortality than the adult stage, but larvae and juveniles showed similar sensitivity. The 96-h LC50 value was pH 3.8 in larval and juvenile stages and pH 3.3 in adult stage.

• Journal of Navigation and Port Research
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• v.35 no.9
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• pp.741-747
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• 2011

Ecological toxicity testing of the whole-effluent from the ozone ballast water treatment system was conducted as specified in the quality assurance project plans (QAPP). The growth inhibition test with microalgae, acute aquatic toxicity test with the Rotifer reproduction, toxicity test (or population growth) with the Rotifer, survival and growth toxicity test with larval fish and sediment toxicity test with amphipod were carried out to evaluate ecological toxicity on the movile test barge.

• Journal of Aquaculture
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• v.12 no.3
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• pp.229-236
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• 1999

in the present study, the zinc toxicity to larval development and seed attachment of the abalone, Haliotis discus hannai was obtained under continuous flow through system. The zinc concentration melted from zinc coating pipe for 7 months ranged from $89.00\pm2.55 \mu\textrm{g}/\ell to 15.23\pm2.58\mu\textrm{g}/\ell(Y=0.85M^2-19.71+109.96)$. Treatments were carried out with zinc concentration $0~160 \mu\textrm{g}/\ell$. The maximum and minimum of fertilization rate were $87.7\pm5.3%$ in control, $83.7\pm7.6%$ in zinc concentration $160\mu\textrm{g}/\ell$, respectively. The maximum and minimum of hatching rate were $87.5\pm4.5%$ in zinc concentration $10\mu\textrm{g}/\ell$, $79.3\pm5.6%$ in zinc concentration $160\mu\textrm{g}/\ell$, respectively. Both of the results were not significantly different (P>0.05). But the normality rate, setting rate and survival rate of abalone larvae at over zinc concentration TEX>$20\mu\textrm{g}/\ell$ decreased rapidly and showed significantly different from those of the other group(P<0.05).

• Journal of fish pathology
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• v.10 no.1
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• pp.65-72
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• 1997

In the present study, acute toxicity data were obtained for hydrogen sulfide to larvae and adults of blue crab Portunus trituberculatus, white shrimp Metapenacus monoceros and prawn Macrobrachium nipponense under continuous flow through system. The larvae 96hr-$LC_{50}$ values of hydrogen sulfide were 7.3, 9.3 and $9.0{\mu}g/\ell$ for P. trituberculatus, M. monoceros and M. nipponense respectively. The larval sensitivity of the three crustaceans studied for the hydrogen sulfide was in the order of P. trituberculatus> M. nipponense> M. monoceros. The adults 96hr-$LC_{50}$ values of hydrogen sulfide were 42.5, 37.8 and $56.6{\mu}g/\ell$ for P. trituberculatus, M. monoceros and M. ripponense, respectively. The order of toxicity of hydrogen sulfide to adults of the three crustaceans was P. tritruberculatus> M. monoceros> M. nipponense. The larval/adult ratios of hydrogen sulfide toxicity were 5.8, 4.1 and 6.3 for P. trituberculatus M. monoceros and M. nipponense respectively, and larvae were found to be more sensitive to hydrogen sulfide than adults in all cases.

• Journal of Environmental Health Sciences
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• v.28 no.4
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• pp.17-22
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• 2002

In crustaceans, as in other arthropods, the molt cycle and the physiological process of growth are controlled by molting hormones (MH) which are steroid hormones, the ecdysteroids. Ecdysteroids are major arthropod hormones which control both development (embryonic and larval molts, metamorphosis) and reproduction. The purpose of the present study was to evaluate both fenarimol and methoprene for embryotoxicity to daphnids. The embryotoxicity associated with each compound was assessed to discern whether the embryotoxicity of methoprene might be due to ecdysone agonist and the ecdysone antagonistic effects of fenarimol on Daphnia embryo. Exposure of daphnids for three weeks to 50 M methoprene resulted in a significantly high incidence of offspring that exhibited general toxicity. This exposure concentration had significant effects on the overall number of embryo death. However, exposure to 3 or 1 $\mu$M fenarimol were no significant effects on the embryo toxicity. The incidence of both of these toxicity increased with methoprene exposure. This observation suggest that methoprene showed embryonic general toxicity during embryo development, while, only fenarimol showed weak general toxicity with early stages of embryonic development.

• The Korean Journal of Ecology
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• v.15 no.3
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• pp.257-265
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• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.209-214
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• 2004

A method for rapid acute toxicity test based on temperature control of Ceriodaphnia dubia has been developed and evaluated. A new toxicity test based on temperature control (TTBTC) which are based on temperature control, was developed and compared for the adsorption of the better methodology for short-term toxicity screening. Initially, daphnid larval are exposed to toxicants and at the same time the temperature of the water bath containing media is increased to high temperature $(35.5^{\circ}C).$ After 1.25 hrs of contact time, the number of the daphnids, either living (no toxic effect) or dead (toxic effect), is counted by the naked eyes. Effect of exposure time on test sensitivity was not significantly different between 1 to 1.5 hr. Comparison of the rapid 1.25 hr acute toxicity test developed in this study and the standard 48 hr acute toxicity test using heavy metals, cyanide and pentachlorophenol indicated that the 1.25 hour test provides an acceptable level of sensitivity in toxicity test for C. dubia.