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Dioxin Level 2021

Dioxin Level 2021

Dioxins in Air - Measurement Results of 2021

Month
Sampling Date
Concentrations
Central/Western
Tsuen Wan
January 22-01-2021 -- 0.075
22-01-2021 0.068 --
February 07-02-2021 0.013 --
21-02-2021 -- 0.009
March 05-03-2021 0.024 --
17-03-2021 -- 0.009
April 10-04-2021 -- 0.015
28-04-2021 0.010 --
May 10-05-2021 0.008 --
22-05-2021 -- 0.008
June 05-06-2021 -- 0.020
08-06-2021 0.009 --
July 03-07-2021 -- 0.008
21-07-2021 0.008 --
August 02-08-2021 0.008 --
14-08-2021 -- 0.008
September 01-09-2021 0.008 --
13-09-2021 -- 0.008
October 13-10-2021 -- 0.008
25-10-2021 0.009 --
November 18-11-2021 0.009 --
30-11-2021 -- 0.022
December  06-12-2021  0.016  --
 18-12-2021  -- 0.022
Annual Average
 0.016 0.018

 

Chart of Dioxins in Air - Measurement Results at Central/Western monitoring station in the past 5 years (2017 - 2021)

Dioxins in Air - Measurement Results at Central/Western monitoring station in the past 5 years (2017 - 2021)

Chart of Dioxins in Air - Measurement Results at Tsuen Wan monitoring station in the past 5 years (2017 - 2021)

Dioxins in Air - Measurement Results at Tsuen Wan monitoring station in the past 5 years (2017 - 2021)

Chart of Dioxins in Air - Central/Western and Tsuen Wan monitoring station Annual Average (1998 - 2021)

Dioxins in Air - Central/Western and Tsuen Wan monitoring station Annual Average (1998 - 2021)


NOTE :

The Trend
  • The dioxins levels in Hong Kong are low and the trend is generally downwards. Due to seasonal factors, the dioxins levels during the winter months are in general higher than that in the summer months.
 
The Procedure
  • The dioxins samples collected every month are sent to the Hong Kong Government Laboratory for analysis. The analytical work requires the use of sophisticated instruments and involves complex extraction processes which usually take at least two to three weeks. The Environmental Protection Department will post the data on the website once the report is available.
 
The Quantification Method
  • The dioxins figures are 24-hour average concentrations in pg I-TEQ /m3, and are expressed as toxic equivalent (I-TEQ) concentration of 2,3,7,8 - Tetrachlorodibenzodioxin (TCDD). They are calculated based on the International Toxic Equivalent Factors (I-TEF) of the North Atlantic Treaty Organization (NATO/CCMS) using 17 types of dioxin-like compound of structurally closely related chemical families and having similar chemical properties. For congener concentrations that are lower than the estimated minimum sample detectable level (EMSDL), one half of the EMSDL is used in calculating the I-TEQ concentration.