A Government spokesman said today (November 1) that relevant departments have all along been following up on the suspected irritant odour incident reported in different areas of Tuen Mun on October 28.

     The Fire Services Department (FSD) received 18 emergency calls regarding a pungent odour in Tuen Mun district between 3.33pm and 4.25pm on October 28. The FSD immediately despatched its personnel to investigate along Pui To Road, Ming Kum Road, Tin King Road, Shek Pai Tau Road, Ching Chung Koon Road, Tsun Wen Road and its vicinity, as well as entering the Tai Hing Operational Base for investigation. No unusual smell was detected during the operation. On the following two days (October 29 and 30), the FSD continued to conduct investigations into the relevant areas and again could not detect any unusual smell. The FSD did not receive any further emergency calls from the public reporting unusual odours in these areas.

     Since 3.34pm on October 28, Police also received multiple reports that there was an irritant odour in the vicinity of Tuen Mun. Police and FSD officers attended the scene, yet initial investigations could not confirm the odour's cause and origin. The incident was classified as an odd smell found case. Police also clarified that Police did not use tear gas or conduct testing of any unknown gas in Tuen Mun during daytime on that day, as circulated on the Internet.

     The Environmental Protection Department (EPD), meanwhile, received 10 complaints of an odd smell between 3.50pm and 4.59pm on October 28. Upon arrival on site at around 5.35pm and having touched base with FSD officers, EPD officers conducted investigations in the vicinity of Tai Hing Operational Base, Blossom Garden, Venice Garden, Tuen Mun North West Swimming Pool, Leung King Estate and Tin King Estate. No obvious smell or suspicious odour could be traced.

     The EPD officers conducted investigations again on October 29 and 30, with the area expanded to cover Kin Sang Estate, Shek Pai Tau Road, Shan King Estate, Tai Hing Estate, Chelsea Heights, Choy Yee Bridge, Ho Tin Stop, Tuen Mun Stop, Tuen Mun Heung Sze Wui Road and Siu Hei Stop. Drainage manhole covers as well as exhaust outlets of food premises and industrial buildings along the way in the area were also inspected in order to trace any possible residue smell or its source, but none was detected.

     The EPD analysed the meteorology and air quality monitoring data obtained on October 28. The South China region was affected by a southward moving northeast monsoon on that day. The wind direction in Hong Kong changed from easterly to north-westerly since noon and brought in an air mass with a higher background pollution level, resulting in higher than normal pollutant concentrations (including ozone, nitrogen dioxide, PM10 and PM2.5) since around noon. Elevated pollution levels in Hong Kong caused by a northeast monsoon occur often in autumn and winter. Its impact could affect various regions in Hong Kong, not only Tuen Mun. Exposure to ozone can cause irritating effects on humans. However, the level of ozone recorded on October 28 was not exceptionally high for this season. The highest concentration recorded on that day was less than half of the highest value recorded this September. It is not conclusive that ozone was the main cause of the complaints raised.

     Relevant departments will continue to monitor the development of the situation and will conduct follow-up investigations if there is new information or irritant odours occur again.

Ends/Friday, November 1, 2019
Issued at HKT 13:15

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