中大公布第二批校園環境檢測結果
香港中文大學（中大） 早前委託獨立認可實驗室於不同時間在校園不同地點，抽取空氣、水質及泥土樣本，並送往化驗。大學已收到了第二批校園環境檢測結果。
因應有大學成員對校園可能殘留CS（鄰-氯代苯亞甲基丙二腈）的疑慮，校方已經進一步安排樣本檢測，預計將於二至三星期後收到結果，並盡快公布。
今日（12月12日）公布的第二批校園環境檢測結果包括13個泥土樣本（#1至#12 、S8）以及兩個水樣本（W9、W10）的化驗結果，摘要及參考水平如下﹕
(1) 泥土樣本
表一﹕泥土樣本（#1 至#12）
污染物
測試結果
參考水平
參考文件
二噁英
0.0037至0.0059 毫微克/克
1毫微克/克
香港環保署發出的「按風險釐定的土壤污染整治標準（公園）」
總多氯聯苯
< 0.2毫克/公斤
0.756毫克/公斤
多環芳香烴
< 0.500至2.05毫克/公斤
3.83至10,000毫克/公斤
表二﹕泥土樣本（S8）
污染物
測試結果
參考水平
參考文件
二噁英
0.12 毫微克/克
1毫微克/克
香港環保署發出的「按風險釐定的土壤污染整治標準（公園）」
總氰化物
< 1 毫克/公斤
4,900毫克/公斤
總多氯聯苯
< 0.200毫克/公斤
0.756毫克/公斤
多環芳香烴
< 0.500毫克/公斤
3.83至10,000毫克/公斤
(2) 水樣本
表三﹕水樣本（W9 及 W10）
污染物
測試結果
參考水平
參考文件
二噁英
4.6至4.7 皮克/公升
30皮克/公升
美國國家環境保護局（USEPA）建議的飲用水標準
總氰化物
< 0.05毫克/公升
0.2毫克/公升
總多氯聯苯
< 0.50 微克/公升
0.5 微克/公升
多環芳香烴
< 0.1 微克/公升
0.1 至 0.4 微克/公升
結論
(1) 泥土樣本
化驗結果顯示12個泥土樣本（#1至#12）的二噁英含量遠低於香港環保署在2007年發出的《按風險釐定的土地污染整治標準的使用指引》中「按風險釐定的土壤污染整治標準（公園）」之數值。這表示二噁英在這些泥土（#1至#12）的含量水平並不顯著，化驗結果與距離2號橋較遠位置的泥土樣本 （S1至S7、S9） 相若 （見表一）。
至於總多氯聯苯的化驗結果，所有泥土樣本 （#1 - #12）都遠低於前述由香港環保署發出的使用指引中（公園）標準之總多氯聯苯含量 (0.756毫克/公斤)。（見表一）
關於泥土樣本 (#1 - #12) 中多環芳香烴的含量，全部均低於參考文件中所規定的水平 （見表一）。 至於多環芳香烴中個別的化合物含量，可於此處瀏覽。
一個含有黑色煙熏物質的泥土樣本 （S8），在夏鼎基運動場裡被火燒焦的墊褥附近採集。測試結果顯示二噁英的含量相比其他泥土樣本為高，但仍相等於使用指引中的參考水平大約十分之一。這個略高的數值可能是由燃燒塑膠或墊褥的塑料部分引起。S8的其他測試參數例如總氰化物、總多氯聯苯和多環芳香烴，它們的含量遠低於在相關參考文件所規定的最低數值（見表二）。
(2) 水樣本
兩個水樣本從賽馬會研究生宿舍（一座）採集。化驗結果顯示兩個水樣本（W9 及 W10）中二噁英含量介乎4.6至4.7皮克/升。根據美國國家環境保護局建議的飲用水標準，其水樣本 （W9 & W10）中二噁英含量並不顯著。其他測試參數例如總氰化物、總多氯聯苯和多環芳香烴，它們的含量遠低於在相關參考文件所規定的最低數值 （見表三）。
從上述結論可見，這些污染物在泥土（#1 至 #12、S8）和水（W9 及W10）樣本的含量對健康的危害不顯著。
至於其他測試結果，大學收到後盡快公布。
相關數據可於此處瀏覽。
CUHK Releases the Second Batch of Test Results on Campus Environment
The Chinese University of Hong Kong (CUHK) earlier appointed an independent accredited laboratory to collect air, water and soil samples at various locations and at different times on campus and sent them for testing. The University has just received the second batch of test results.
In addition, in response to the concerns of some University members over the level of CS (2-chlorobenzalmalononitrile) on CUHK campus, the University has arranged to conduct another round of tests. The results will be announced as soon as they are received in 2-3 weeks’ time.
Here is the summary of the second batch of test results including 13 soil samples (#1-#12 & S8) and 2 water samples (W9 & W10) compared with the guidance notes/international standards.
(1) Soil samples
Table 1: For soil samples (#1 - #12)
Contaminant
Test results
Reference Level
Reference Document
Dioxins
0.0037-0.0059 ng/g
1 ng/g
Risk-Based Remediation Goals (RBRGs) for Soil – Public Parks, published by Hong Kong Environmental Protection Department
Total PCBs
< 0.2 mg/kg
0.756 mg/kg
PAHs
< 0.500-2.05 mg/kg
3.83-10,000 mg/kg
Table 2﹕For soil sample (S8)
Contaminant
Test results
Reference Level
Reference Document
Dioxins
0.12 ng/g
1 ng/g
Risk-Based Remediation Goals (RBRGs) for Soil – Public Parks, published by Hong Kong Environmental Protection Department
Total Cyanide
< 1 mg/kg
4,900 mg/kg
Total PCBs
< 0.200 mg/kg
0.756 mg/kg
PAHs
< 0.500 mg/kg
3.83-10,000mg/kg
(2) Water samples
Table 3: For water samples (W9 & W10)
Contaminant
Test results
Reference Level
Reference Document
Dioxins
4.6-4.7 pg/L
30 pg/L
Drinking Water Standards from USEPA
Total Cyanide
< 0.05 mg/L
0.2 mg/L
Total PCBs
< 0.50 µg/L
0.5 µg/L
PAHs
< 0.1 µg/L
0.1-0.4 µg/L
Conclusion
(1) Soil samples
Among the 12 soil samples (#1-#12), the dioxins (I-TEQ) are well below the Risk-Based Remediation Goals (RBRGs) of dioxins in soil (I-TEQ) for public parks as quoted in the Guidance Manual for Use of Risk-Based Remediation Goals for Contaminated Land Management published by Hong Kong Environmental Protection Department (HKEPD) in 2007. This indicates that the dioxins (I-TEQ) levels in these soil samples (#1 - #12) are not significant, and the results are comparable to soil samples (S1-S7 & S9) collected in the more distant locations away from No. 2 Bridge (see table 1).
Based on the test results of Total Polychlorinated Biphenyls (PCBs), all soil samples (#1 - #12) are lower than the respective limits of PCBs level (0.756 mg/kg) for public parks cited in the aforementioned Guidance Manual from HKEPD (see table 1).
Regarding the Polycyclic Aromatic Hydrocarbons (PAHs) levels for these soil samples (#1 - #12), all of them are below the level as required by the reference document (see table 1). For the figures of individual PAH compounds, please click here.
A soil sample with black-smoked materials (S8) was collected in the vicinity of the burned mattress in Sir Philip Haddon-Cave Sports Field. The test result of the dioxins (I-TEQ) level is relatively higher than that of other soil samples though it is only about one tenth of the reference level cited in the Guidance Manual. The possible reason for the elevated result may be due to the burning of rubber or plastic components of the mattress. For the other testing parameters such as Total Cyanide, Total Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs) for the sample (S8), they are all well lower than their respective limits as required by the related reference documents (see table 2).
(2) Water samples
Two water samples (W9 & W10) had been collected from Jockey Club Postgraduate Hall 1. The test results reveal that the dioxins (I-TEQ) levels for both samples (W9 & W10) are from 4.6 to 4.7 pg/L. In accordance with drinking water standards from United States Environmental Protection Agency (USEPA), the dioxins levels for these water samples (W9 & W10) are not significant. For the other testing parameters such as Total Cyanide, Total Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs), they are all much below their respective limits as required by the related reference documents (see table 3).
In view of the aforementioned interpretation, the health hazards of these contaminants from the soil (#1 - #12 & S8) and water (W9 & W10) samples are negligible.
Other test results will be announced as soon as they are available. Related information may be viewed here.
