## 3 Results and Discussion  
### Data of the Water Quality Monitoring  
Descriptive statistics of the physicochemical parameters of the washing water quality are summarized in Table 1. Determination of the dissolved organic carbon (DOC) with TOC analyzer is the modern and rapid method. However, limit values of DOC are still under consideration by some researchers [2; 5; 7; 10; 30; 45]. DOC can also be described by means of COD or BOD\({}_{5}\). Results of this research showed the average fit of the linear regression models (Figure 4). Figure 4: Linear regression models of the BOD and COD to DOC. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Parameter/**} & \multicolumn{1}{c}{**SS**} & \multicolumn{1}{c}{**TDS**} & \multicolumn{1}{c}{**EDD\({}_{8}\)**} & \multicolumn{1}{c}{**COD\({}_{\text{C}}\)**} & \multicolumn{1}{c}{**COD\({}_{\text{Mo}}\)**} & \multicolumn{1}{c}{**N\({}_{\text{Si}}\)**} & \multicolumn{1}{c}{**N\({}_{\text{min}}\)**} & \multicolumn{1}{c}{**P\({}_{\text{Mat}}\)**} & \multicolumn{1}{c}{**DOC**} & \multicolumn{1}{c}{**Colour**} & \multicolumn{1}{c}{**SUVA\({}_{\text{254}}\)**} \\ \multicolumn{2}{c}{**Sampling Point**} & \multicolumn{1}{c}{**m\(\mathbf{L^{-1}}\)**} & \multicolumn{1}{c}{**m\(\mathbf{L^{-1}}\)**} & \multicolumn{1}{c}{**m\(\mathbf{S}\) \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c} \hline \hline
**Parameter/** & **SS** & **TDS** & **PDJ** & **EC** & **BODJ\({}_{\text{R}}\)** & **CODJ\({}_{\text{C}}\)** & **CODJ\({}_{\text{Mn}}\)** & **N\({}_{\text{Si}}\)** & **N\({}_{\text{min}}\)** & **P\({}_{\text{M}}\)** & **DOC** & **Colour** & **SUVA\({}_{\text{2584}}\)** \\
**Sampling Point** & **mg L\({}^{-1}\)** & **mg L\({}^{-1}\)** & **pH** & **m5O\({}_{2}\) L\({}^{-1}\)** & **mgO\({}_{2}\) L\({}^{-1}\)** & **mgO\({}_{2}\) L\({}^{-1}\)** & **mgO\({}_{2}\) L\({}^{-1}\)** & **mg L\({}^{-1}\)** & **mg L\({}^{-1}\)** & **mg L\({}^{-1}\)** & **Dilation** & **SUVA\({}_{\text{2584}}\)** \\ \hline
**Mean** & **345** & **519** & **7.6** & **604** & **57** & **197** & - & **3** & **nd** & 0.2 & 68 & 3 & **5.66** \\ SD & 486 & 215 & 0.56 & 162 & 86 & 132 & - & 1 & nd & 0.1 & 34 & 2 & - \\ CV, \% & 141 & 42 & 7.4 & 27 & 151 & 67 & - & 51 & nd & 66 & 49 & 50 & - \\ Min & 2.4 & 176 & 6.98 & 261 & 4.5 & 21.6 & - & 0.1 & nd & 0 & 32 & 1 & 2.2 \\ Max & 1543 & 768 & 8.46 & 726 & 504 & 375 & - & 4 & nd & 0.4 & 120 & 7 & 10.83 \\ \hline
**Average** & **2335** & **946** & **6.78** & **904** & **1729** & **3287** & **440** & **54** & **2.5** & **9.8** & **345** & **6** & **3.18** \\ \hline
**Limits** & Canada **\({}^{**}\)** & 25-40 & - & - & - & 20-35 & - & - & -2-8 & 1-3 & 0.5-1.0 & & - & - \\ \hline LT *** & - & 2000 & 6.5-8.5 & 2500 & 4629\({}^{*}\) & 125 & - & 30 & 28.5 & 4 & (\({}^{*}\)) & 3 & - \\ \hline EU *** & 35-60 & - & - & - & 25 & 125 & - & 10-15 & - & 1-2 & - & - & - \\ \hline HN 242003 & - & - & 6.5-9.5 & - & - & - & 5 & - & 51 & - & - & - & - \\ \hline \end{tabular}
\end{table} 
Table 1: _Cont._It can be seen from the model, that the DOC limit values of the root vegetable washing water are in the range between 100 to 122 mg L\({}^{-1}\). Contamination of municipal wastewater depends of its origin and load, particle sizes, rainfalls, storm events, and other conditions [2; 3; 5; 9]. According to the literature suspended solids (SS) of the root vegetables washing water vary within the range 85-930 mg L\({}^{-1}\); total dissolved solids (TDS)--425-4650 mg L\({}^{-1}\), pH--6.80-11.1, chemical oxygen demand COD mg L\({}^{-1}\)--160-800 mg L\({}^{-1}\), soluble COD--140-350 mg L\({}^{-1}\), biological oxygen demand BOD\({}_{5}\)--73-1700 mg L\({}^{-1}\), SUVA index--1-6, Kjeldahl nitrogen N\({}_{\rm Kj}\)--11.4-165 mg L\({}^{-1}\), inorganic nitrogen N--2.81-75.5 mg L\({}^{-1}\), ammonia NH\({}_{3}\)-N--3.8-75 mg L\({}^{-1}\),nitrites NO\({}_{2}\)-N--<0.005-0.195 mg L\({}^{-1}\), nitratesNO\({}_{3}\)-N < 0.005-3.17 mg L\({}^{-1}\); total phosphorus P\({}_{\rm tot}\)--3.0-320 mg L\({}^{-1}\)[7; 30; 31; 45; 46; 47].