# Occupational Inhalation Health Risk Assessment of TCE Exposure in the Korean Manufacturing Industry
## 3 Results
### Exposure Assessment  
The AM and SD values of the TCE measurements are listed in Table 3. The five industries with the largest AM presence were manufacturers of fabricated metal products (4.67 ppm), manufacturers of medical, precision, and optical instruments, watches, and clocks (4.07 ppm), manufacturers of electronic components, computers, visual, sounding, and communication equipment (3.62 ppm), other manufacturing (3.55 ppm), and manufacturers of other machinery and equipment (2.89 ppm). The industry with the lowest AM was coke, briquettes, and refined petroleum products' manufacturers (0.02 ppm).  
### Exposure Assessment  
The AM and SD values of the TCE measurements are listed in Table 3. The five industries with the largest AM presence were manufacturers of fabricated metal products (4.67 ppm), manufacturers of medical, precision, and optical instruments, watches, and clocks (4.07 ppm), manufacturers of electronic components, computers, visual, sounding, and communication equipment (3.62 ppm), other manufacturing (3.55 ppm), and manufacturers of other machinery and equipment (2.89 ppm). The industry with the lowest AM was coke, briquettes, and refined petroleum products' manufacturers (0.02 ppm).  
\begin{table}
\begin{tabular}{c c c} \hline
**Steps** & **Categories** & **Values** \\ \hline POD & & NOAEL 100 ppm (rat, inhalation) \\ \hline Quantitative & NOAELADJ (7/8 \(\times\) 5/5 \(\times\) 0.83/1.25) & 0.58 \\ correction & NOAELHEC & 1 \\ \hline  & Interspecies & 3 \\ Uncertainty & Intraspecies & 5 \\ correction & Duration & \(\geq\)6 months & 1 \\  & Severity & 1 \\ \hline RfCwork\({}_{\text{non-carcinogen}}\) & 100 ppm \(\times\) 0.58 \(\div\) 15 & 3.87 ppm \\ \hline \end{tabular}
\end{table}
Table 1: Values for the derivation of the RfCwork\({}_{\text{non-carcinogen}}\) of TCE.  
\begin{table}
\begin{tabular}{c c c c c} \hline
**Steps** & **Categories** & **Values** \\ \hline POD & Kidney & & Inhalation unit risk \\  & & & 5.49 \(\times\) 10\({}^{-3}\) risk/ppm \\ \hline \multicolumn{5}{c}{IUR\(\div\) CF =} \\ IURworkplace 1  & IUR \(\div\) 4.2(20/10 \(\times\) 365/260 \(\times\) 70/40)/(70/60) & 1.31 \(\times\) 10\({}^{-3}\) risk/ppm \\ \hline RfCwork\({}_{\text{carcinogen}}\)2  & 1 \(\div\) (1.31 \(\times\) 10\({}^{-3}\) risk/ppm) \(\times\) 10\({}^{-4}\) risk & 7.65 \(\times\) 10\({}^{-2}\) ppm \\ \hline \end{tabular}
\end{table}
Table 2: Values for the derivation of the RfCwork\({}_{\text{carcinogen}}\) of TCE.  
\begin{table}
\begin{tabular}{c c c c c} \hline
**KSIC** & & & & \\
**Code** & **Type of Manufacturing Industry** & **AM (ppm)** & **SD** & **N** & **Range (ppm)** \\ \hline
25 & Fabricated metal products (except machinery and furniture) & 4.67 & 7.94 & 1175 & 0–86.48 \\
27 & Medical, precision, and optical instruments, watches, and clocks & 4.07 & 6.88 & 235 & 0–33.53 \\
26 & Electronic components, computers, visual, sounding, and & 3.62 & 6.71 & 1346 & 0–46.72 \\
33 & Other & 3.55 & 7.42 & 130 & 0–49.29 \\
29 & Other machinery and equipment & 2.89 & 6.19 & 618 & 0–48.80 \\
28 & Electrical equipment & 2.53 & 6.72 & 262 & 0–57.28 \\
30 & Motor vehicles, trailers, and semitralers & 2.09 & 4.32 & 623 & 0–41.76 \\
16 & Wood and products of wood and cork, except furniture & 2.07 & 5.88 & 71 & 0–36.19 \\
23 & Other non-metallic mineral products & 1.62 & 5.04 & 39 & 0–27.21 \\
17 & Pulp, paper, and paper products & 1.54 & 6.52 & 47 & 0–35.99 \\
24 & Basic metals & 1.22 & 3.21 & 180 & 0–21.47 \\
22 & Rubber and plastic products & 1.18 & 4.36 & 261 & 0–38.59 \\
18 & Printing and reproduction of recorded media & 0.88 & 3.53 & 165 & 0–26.83 \\
20 & Chemicals and chemical products (except pharmaceuticals and & 0.66 & 3.23 & 379 & 0–32.33 \\  & medicinal chemicals) & & & & \\ \end{tabular}
\end{table}
Table 3: Arithmetic mean and standard deviation for the measurement values.