## 3 Results and Discussion
### Residual Pesticides in 40 Korean Agricultural Soils
[34] reported that oxadiazon had a high adsorption rate in soil with high organic matter content, and exhibited a lower desorption rate in comparison to the lower organic-matter-possessing soils. In this study, we focused on the detection of endosulfan, which has been banned in Korea since 2012. Currently, endosulfan is registered as a POP, and most countries around the world have banned it. In our study, it was detected at a level of 0.006-0.040 ppm, and the detection frequency was 7.5% (Table 7). For endosulfan, a report on the translocation from soil to rice farming has been reported [35], and two concentrations, 3 and 10 mg kg\({}^{-1}\), were found in paddy soils, showing 0.546 and 1.258 mg kg\({}^{-1}\) of endosulfan in the rice straw, respectively. However, endosulfan was not found in brown rice. For cucumbers grown in \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Ulsan Soils**} & **Determined** & **Determined** & **Pohang Soils** & **Determined** & **Determined** \\  & **Pesticides** & **Amounts (\# kg\({}^{-1}\))** & **Pesticides** & **Amounts (\# kg\({}^{-1}\))** \\ \hline  & & & & Carbendarizm & 0.001 * \\  & & & & Carpropamide & 0.003 * \\  & & & & Flubendiamide & 0.005 * \\  & & & & lprobenfos & 0.014 \\  & & & & Isoprothiolane & 0.002 * \\  & & & & Oxadiazon & 0.002 * \\  & & & & Tricyclazole & 0.020 \\  & & & & Butachlor & 0.006 * \\  & & & & Thifluzamide & 0.020 \\  & & & & Fenoxanil & 0.034 \\ \hline  & & & & Carbendarizm & 0.001 * \\  & & & & Carpropamide & 0.002 * \\  & & & & brobenfos & 0.002 * \\  & & & & Isoprothiolane & 0.008 \\  & & & & Oxadiazon & 0.013 \\  & & & & Tricyclazole & 0.006 * \\  & & & & Fenoxanil & 0.010 \\ \hline  & & & & Carpropamide & 0.003 * \\  & & & & Iprobenfos & 0.005 * \\  & & & & Oxadiazon & 0.006 * \\ \hline \hline \end{tabular}  
* Indicates that the determined value was lower than the limit of quantification. ** Indicates that there were no pesticides determined by the analytical methods used in this study.  
\end{table} 
Table 7: Cont. endosulfan-treated soils with two levels, 20 and 40 mg kg\({}^{-1}\), its residual amount reached 7.8 and 14.5 mg kg\({}^{-1}\), respectively, after 15 days of growth [17]. Recently, [PERSON] et al. [16] reported that they found the highest endosulfan residues near farmland, and an endosulfan metabolite, endosulfan sulfate, was dominant in most soil samples. Endosulfan and its sulfate were found in the soils at an average of 0.8 mg kg\({}^{-1}\)[16]. Therefore, it is necessary to monitor endosulfan and its metabolites in agricultural soils on a regular periodic basis, even if banned in Korea. Chlorantraniliprole is an anthranilic-acid-related insecticide that shows a selective activator on insect ryanodine receptors, interfering with muscle contraction [36]. This pesticide presents a half-life ranging from 12.6 to 23.1 days in soil [37]. In this study, chlorantraniliprole was detected at a concentration of 0.008-0.038 mg kg\({}^{-1}\), and the detection frequency was 5% (Table 7). Although there have been no reports on the residual pattern of this pesticide in paddy soil in Korea, it was detected in perilla leaf, brassica leafy vegetables, and spinach from 2010 to 2012 at a level of 0.129-0.805 mg kg\({}^{-1}\)[13]. In addition, carbendazim (8/40) and carbropamid (7/40) were found as pesticides detected below the LOQ, but with high detection frequency.