• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.264-271
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• 2004

An aquatic food chain was constructed to provide information of bioaccumulation of DEHP as followed: phytoplankton(Scenedesmus subspicatus) ${\rightarrow}$ zooplankton(Daphnia magna) ${\rightarrow}$ fish(Oryzias latipes). After 10 days of exposure to DEHP, the fish and culture water were analyzed for residual concentration of DEHP and BAF(Bioaccumulation Factor) was determined. In addition, BCF(Bioconcentration Factor) was calculated in exposure tank in which fish were only exposed DEHP by culture water. These experiments provide the relative importance between BAF and BCF. In this study, BCF and BAF did not show any significant difference. Another work in this study was model construction and application to investigate the effect of food chain structure to BAF in higher organism (fish). The model constructed in this study considered the biological characteristics of DEHP such as metabolic parameters, as well as the chemical characteristics such as solubility. This model could be used in prediction of bioaccumulation level in dependent of various food chain structures, when the target organisms or chemicals would be changed.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.550-558
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• 2021

In a radiotracer study, the bioaccumulation and efflux of metals in earthworms (Eisenia fetida) exposed to soil spiked with ZnO and Ag nanoparticles (AgNP) were compared to those exposed to soil spiked with ionic Zn and Ag. Additionally, the bioavailability and chemical mobility of nano- and ionic metals in the soil were estimated using the sequential extraction method and compared to the bioaccumulation factor(BAF). The BAF for ZnO (0.06) was 31 times lower than that for Zn ions (1.86), suggesting that ZnO was less bioavailable than the ionic form in contaminated soil. In contrast, the BAFs for two types of AgNPs coated with polyvinylpyrrolidone (0.12) or citrate (0.11) were comparable to those of ionic Ag (0.17). The sequential extraction of metals from the soil suggests that the chemically mobile fractions in the Zn ion treatment were higher(35%) than those (<20%) in the Ag ion treatment, which was consistent with the greater BAFs in the former than the latter. However, the chemical mobility in the ZnO treatments did not predict bioavailability. The efflux rates of Ag (3.2-3.8% d^-1) in the worms were 2-3×those(1.2-1.7% d^-1) for Zn.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.101-108
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• 2016

Concentrations of Chromium(Cr) and Manganese(Mn) in several kinds of dewatered organic sewage sludges generated from wastewater treatment plants of Pocheon City, Gyeongii Province were examined. In addition, bioaccumulations of Cr and Mn in the body of earthworm Eisenia fetida were also investigated by changing of feed sludge amounts. Cr and Mn concentrations in sludges were in the range of 0.0~0.3 mg/kg and 3.6~17.6 mg/kg, respectively, which would not cause acute toxicities to earthworm population. Cr was bioaccumulated in the earthworm body but bioaccumulation was not proportional to the amount of sludges supplied. The degree of bioaccumulation of Cr decreased in later phase as the supplied amounts of sludges increased. Meanwhile, there were rare bioaccumulation with regard to Mn. In this study, the value ranges of bioaccumulation factor (BAF) for Mn were 0.00~0.12 when 60g of sludges was supplied. In the case of Cr, the value of BAF was 19.33 when 60g of human manure sludge was provided.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.947-956
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• 2009

Residual petroleum hydrocarbons after an oil spill may accumulate in the marine benthic ecosystem due to their high hydrophobicity. A lot of monitoring data are required for the estimation of ecosystem exposure to residual petrochemicals in an ecological risk assessment in the affected region. To save time and cost, the environmental exposure to them in the affected ecosystem can also be assessed using a simple food-web bioaccumulation model. In this study, we evaluated residual concentrations of four selected polycyclic aromatic hydrocarbons (phenanthrene, anthracene, pyrene, and benzo[a]pyrene) in a hypothetic benthic ecosystem composed of six species under two exposure scenarios. Body-residue concentration ranged 5~250 mg/kg body depending on trophic positions in an extreme scenario in which the aqueous concentrations of PAHs were assumed to be one-tenth of their aqueous solubility. In addition, bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were evaluated for model species. The logarithm of bioconcentration factor (log BCF) linearly increased with increasing the logarithm of 1-octanol-water partition coefficient (log $K_{OW}$) until log $K_{OW}$ of 7.0, followed by a gradual decrease with further increase in log $K_{OW}$ without metabolic degradation. Biomagnification became significant when log $K_{OW}$ of a pollutant exceeded 5.0 in the model ecosystem, indicating that investigation of food-web structure should be critical to predict biomagnifications in the affected ecosystem because log $K_{OW}$ values of many petrochemicals are higher than 5.0. Although further research is required for better site-specific evaluation of exposure, the model simulation can be used to estimate the level of the ecosystem exposure to residual oil contaminants at the screening level.

• Economic and Environmental Geology
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• v.54 no.3
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• pp.399-408
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• 2021

Natural soil was artificially contaminated with heavy metals (Cd, Pb, and Zn), and the movement of earthworm was characterized in real time using the ViSSET system composed of vibration sensor and the other components. The manifestation mechanism of ecological toxicity of heavy metals was interpreted based on the accumulative frequency of earthworm movement obtained from the real-time monitoring as well as the conventional indices of earthworm behavior, such as the change in body weight before and after tests and biocumulative concentrations of each contaminant. The results showed the difference in the earthworm movement according to the species of heavy metal contaminants. In the case of Cd, the earthworm movement was decreased with increasing its concentration and then tended to be increased. The activity of earthworm was severely increased with increasing Pb concentration, but the movement of earthworm was gradually decreased with increasing Zn concentration. The body weight of earthworm was proved to be greatly decreased in the Zn-contaminated soil, but it was similarly decreased in Cd- and Pb-contaminated soils. The bioaccumulation factor (BAF) was higher in the sequence of Cd > Zn > Pb, and particularly the biocumulative concentration of Pb did not show a clear tendency according to the Pb concentrations in soil. It was speculated that Cd is accumulated as a metallothionein-bound form in the interior of earthworm for a long time. In particular, Cd has a bad influence on the earthworm through the critical effect at its higher concentrations. Pb was likely to reveal its ecotoxicity via skin irritation or injury of sensory organs rather than ingestion pathway. The ecotoxicity of Zn seemed to be manifested by damaging the cell membranes of digestive organs or inordinately activating metabolism. Based on the results of real-time monitoring of earthworm movement, the half maximal effective concentration (EC50) of Pb was estimated to be 751.2 mg/kg, and it was similar to previously-reported ones. The study confirmed that if the conventional indices of earthworm behavior are combined with the results of newly-proposed method, the mechanism of toxicity manifestation of heavy metal contaminants in soils is more clearly interpreted.