Advisory Council on Food and Environmental Hygiene


Confirmed Minutes of the Twenty-second Meeting

held at 2:30 p.m. on Thursday, 8 July 2004

at Room 1007, 10/F, Citibank Tower, 3 Garden Road, Hong Kong


Professor YUEN Kwok-yung, SBS, JP            (Chairman)

Dr CHAN Hei-ling, Helen

Dr HO Dit-sang, John

Mr HUNG Hak-hip, Peter

Dr Anthony Edward JAMES

Professor KWAN Hoi-shan

Mr LAI Tat-sang, David, MH

Mrs LAM WONG Pik-har, Grace

Ms LAM Wai-ling, Leona, JP

Mr John LEE, JP

Dr LUI Chiu-tong, Jacqueline

Mrs Carrie YAU                                 Permanent Secretary for Health,

                                                            Welfare and Food

Mr Thomas CHAN                             Director of Agriculture, Fisheries

                                                           and Conservation

Mr Gregory LEUNG                          Director of Food and Environmental


Miss Vivian KO                                  (Secretary)


Absent with Apologies


Mr CHAN Bing-woon, SBS, JP

Mr KWOK Chun-wah, Jimmy, MH

Dr LO King-shun

Dr the Hon LO Wing-lok, JP

Dr P Y LAM                                       Director of Health


In Attendance


Health, Welfare and Food Bureau


Mr Eddy CHAN                                 Deputy Secretary for Health, Welfare and

                                                            Food (Food and Environmental Hygiene)


Mr Vincent LIU                                  Principal Assistant Secretary for

                                                            Health, Welfare and Food (Food and

                                                            Environmental Hygiene) 2


Ms Priscilla TO                                  Assistant Secretary for Health,

                                                            Welfare and Food (Food and

                                                            Environmental Hygiene) 1


Mr Louis NG                                     Senior Executive Officer (Food and

                                                            Environmental Hygiene)


Food and Environmental Hygiene Department


Dr S P MAK                                Deputy Director (Food and Public Health)


Dr Y Y HO                                   Consultant (Community Medicine)(Risk Assessment and Communication)


Department of Health


Dr Thomas TSANG                     Consultant (Community Medicine) (Communicable Diseases)


Opening Remarks


                   The Chairman welcomed Members to the meeting. 


Agenda Item 1: Confirmation of the Minutes of the Last Meeting


2.                                         Members confirmed the minutes of the last meeting subject to the following amendments �V


(i)The second sentence of paragraph 27 should be amended as ��Another Member concurred and suggested that the Administration could publicize a ��litter black spot�� hotline so that members of the public could phone in to report litter black spots.��


(ii)              A new paragraph 30 should be added.  


Agenda Item 2 : Matters Arising from the Minutes of the Last Meeting


3.                                         A Member said that he raised at the last meeting that on some occasions street cleansers were found not to properly store their cleansing equipment after cleansing.  FEHD agreed to remind the street cleansing workmen to do so.  However, the problem still existed in the area beneath the flyover at Wong Nai Chung Gap Road.  Mr Gregory LEUNG agreed to follow up. 


Agenda Item 3 : Anti-mosquito Efforts made by the Government


4.                                         The Chairman invited Mr Vincent LIU to present the paper. 


5.                                         A Member said that he supported the establishment of the District Anti-Mosquito Task Force and the establishment of the Anti-Mosquito Support Scheme as new initiatives to strengthen the existing anti-mosquito actions.  However, he was concerned if there would be duplication of work between the Task Force and the District Clean Hong Kong Sub-Committee.  He also suggested that more public education on the role of livestock in the transmission of mosquito-borne diseases should be given. 


6.                                         In response, Mr Liu said that the District Offices were best placed to consider the delineation of responsibilities of the Task Force and the Sub-Committee.  As for public education on mosquito-borne diseases, the Department of Health (DH) published and distributed publicity materials to the public.   Dr Y Y HO added that three types of mosquito-borne diseases were of concern in Hong Kong, namely, dengue fever, malaria and Japanese Encephalitis (JE).  For JE, mosquitoes became infected by feeding on pigs and wild birds infected with the JE virus.  The virus was transmitted to humans through bites by infected mosquitoes.  But for the first two types of mosquito-born diseases, humans contracted the diseases directly from mosquito bites and livestock were not involved in the transmission cycle. 


7.                                         A Member asked about the size of the problem of having mosquito breeding grounds in construction sites and private premises and suggested that heavy fines should be imposed for such breaches.  Mr Leung responded that about 80% of the concerned prosecution cases were related to construction sites and the average and highest fines imposed by the Court were $4,000 and $11,000-12,000 respectively.  The Administration would consider increasing the fine level to enhance deterrence.  As regards private premises, FEHD could only prosecute the occupiers of the concerned private premises under the existing law.  If a breeding ground was found in the common area of private premises, FEHD could not prosecute the concerned management company.  The Administration would consider amending the law so that prosecution actions could be taken against the concerned management company.


8.                                         Addressing a Member��s question about the materials used, residual properties and the environmental impact of the larvicides used, Dr Y Y HO said that two types of larvicide were commonly used, namely, ��BTI�� (a toxin derived from a bacteria) and temephos (a larvicide recommended by the World Health Organization).  There was no environmental concern if these larvicides were used properly.  In response to the Chairman��s query, Dr Y Y HO said that the use of these two larvicides would depend on whether the stagnate water was long standing and the water area.  Apart from these two larvicides, mineral oil could also be used to suffocate the larvae. 


9.                                         A Member remarked that more proactive anti-mosquito measures should be adopted in areas where the Area Ovitrap Index (AOI) was usually found at a high level.  In response, Mr Liu said that FEHD would activate the district inter-departmental anti-mosquito response mechanism once the AOI reached 20% instead of 30% as in the past.  Dr S P MAK said that the Administration had taken anti-mosquito actions as early as February this year.  Early targeted actions were planned for areas which had high AOIs last year and the concerned departments were asked to take proactive measures to prevent breeding grounds and eliminate breeding sources at the black spots identified in the previous year.  Mr Eddy CHAN added that community participation was encouraged through the Home Affairs Department to identify black spots in respective districts so that more focused anti-mosquito measures could be taken. 


10.                                     A Member suggested that a fixed penalty be imposed on the breaches concerning mosquito breeding at construction sites and private premises so as to enhance deterrence.  Mr Leung responded that the Team Clean had considered this proposal, but legal advice suggested that a fixed penalty system was usually adopted when the penalty level was not significant.  As the fine level under the law for breaches concerning mosquito breeding at construction sites and private premises was not low, it was legally more desirable to leave it to the court to determine the penalty.  A Member remarked that given the public health concern arising from the high AOIs measured in many districts and the detection of local JE cases this year, it was opportune to review the legislation now to enhance the deterrent effect against breaches concerning mosquito control and prevention.   Another Member concurred.


11.                                      Mr Liu said that to address the problem of mosquito breeding grounds at construction sites, the Buildings Department was considering not to renew the registration of those contractors who were repeatedly convicted of offences relating to mosquito breeding.  Moreover, contractors were reminded to inspect their construction sites every week to clear out any potential breeding grounds.  Concerned government departments would also step up inspection of construction sites to ascertain if the contractors had taken anti-mosquito measures.


12.                                     A Member supported that a heavier fine should be imposed on the breaches concerning mosquito breeding at construction sites.  He suggested that the Administration could consider publicising the names of offenders to increase the deterrent effect.  In response, Mr Leung said that the names of the convicted contractors were already publicised.  To ensure public scrutiny, it would be more effective to publicize the name of the concerned property development company.  However, it might not be fair to do so because legally it was the contractor and not the property development company who was held responsible. 


13.                                      The Chairman asked whether it was common for local pig farms to be located in close proximity to residential premises.  Mr Thomas CHAN replied that there were some 300 pig farms in Hong Kong and all of them were close to populated areas according to overseas standard.  In fact, residential premises could generally be found within 2 km, the maximum flying distance of Culex tritaeniorhynchus, of these pig farms. 


14.                                     The Chairman said that a horse was found dead of JE in 2002 in Shatin.  He asked whether subsequent investigation revealed that the nearby Culex tritaeniorhynchus carried JE virus.  In response, Mr Thomas CHAN said that it was quite common to find JE virus in Culex tritaeniorhynchus during summer in Hong Kong.   In fact, local pigs were naturally infected and developed immunity.  The sows passed on their immunity to piglets via antibodies in the colostrums.  Because of the maternal antibodies, the piglets had some protection from infection at the time they were exposed to infected mosquitoes.  However, there was a window period of about 2 weeks where the maternal antibodies had disappeared and the piglets might not have fully developed immunity against JE.  During this period, if a piglet carrying JE virus was bitten by a mosquito and the mosquito subsequently bit a human, that human would contract the virus.   The Administration was now studying the feasibility of pig vaccination in local farms against JE.  Consideration was given to using a live vaccine to vaccinate pigs as a killed vaccine was not found very effective.  However, the live vaccine required 2 doses and there should be a one month-span between the first and second doses.  Moreover, the risk associated with reversion to virulence, especially in the environment where the wild strain of virus was active, remained a concern. 


Agenda Item 4 : Safety of Pre-packaged Food Imported from the Mainland


15.                                     The Chairman invited Dr S P MAK to present the paper.


16.                                     Addressing a Member��s question as to whether there was any inspection of non-packaged food for sale in the market, Dr Mak said that the food surveillance programme covered both pre-packaged and non-packaged food. 


17.                                     A Member said that parallel imports were permitted under law in Hong Kong.  However, given the food safety concern, the Administration should review if parallel imports of food products should be regulated.  He also asked if any survey had been conducted to study the proportion of parallel imported food products whose labels did not comply with the local food law of the country/place of origin.  In response, Mr Leung said that this was a very complicated issue as a comprehensive framework was required for the regulation of parallel imported food.  Moreover, not every country and place supplying food products to Hong Kong exercised export control.  It would therefore be difficult to define whether a dealer importing a food item into Hong Kong was an authorized dealer or not.  Before any law amendments were considered, FEHD needed to gather more information to ascertain if parallel imported food items really posed a threat to food safety.  The department had now started work on this issue.


18.                                     Mr Leung went on to say that in the Mainland, all pre-packaged food destined for the Hong Kong market could only be processed and manufactured by the processing plants approved by the General Administration of Quality Supervision, Inspection and Quarantine of the PRC.  These plants were required to meet high production and hygiene standard.  However, for the pre-packaged food destined for the local market, the production standard and quality requirements were usually less stringent.


19.                                     In response to a Member��s query, Dr Mak said that it was not required to label the specific name and amount of preservatives used in a pre-packaged food item.  If a food item was labelled to contain preservatives, FEHD would test for the presence of the common types of preservatives that would be used for the specific food item, and check if the quantity exceeded the maximum limit permitted under law.   


20.                                     A Member said that the composition of the two food products of the same kind and under the same brand name might also be different if these products were originally produced for different consumer markets.  If a parallel imported food product was found to contravene with the local food law, this would also affect the sale and reputation of the same food product of the same brand name introduced by an authorized dealer or importer because consumers might not be able to differentiate the two.  He agreed that the issue of parallel imports was complicated and the food trade would be willing to give their views to the Administration.  Mr Leung said that the Administration would look into the issue of parallel imports with a view to further ensuring food safety in Hong Kong.  He also agreed to exchange views with the trade on the issue at an appropriate time.


21.                                     Responding to a Member��s suggestion that the Mainland authorities should give a code for the food products approved for export to Hong Kong, Mr Leung said that there were about 10 000 food processing plants in the Mainland which were approved to manufacture food products for export..  FEHD had asked the Mainland authority if the list of the processing plants could be posted on the Internet and their reply was awaited.  


22.                                     A Member remarked that the recent reports of sub-standard food items in the Mainland had aroused great public concern over the food safety of food imported from the Mainland.  He supported that the Government should examine the problem to see if any further measures could be put in place to ensure food safety. 


23.                                     The Chairman asked if a comparative study about the food additives and contaminants in food products imported from the Mainland and imported food products from other sources had been conducted.  Mr Leung pointed out that pre-packaged food imported from the Mainland accounted for a significant proportion of the total pre-packaged food consumed in Hong Kong and that the failure rate of the samples tested under the regular surveillance programme was so far satisfactory.  This reflected that the problem in general might not be as serious as perceived and parallel imported food products were more likely to be the main concern.   FEHD would conduct more study in the year with emphasis on the food products imported from the Mainland. 


24.                                     In response to the Chairman��s query about the control over health food, Dr Mak said that health food which contained medicine or Chinese medicine would be regulated under the respective legislation governing their use.  Otherwise, health food would be considered as general food items and be subject to local food legislation.  


25.                                     A Member asked if the problem of sub-standard food products reported in the Mainland were more serious in certain cities/provinces and if yes, more effective measures could be taken to inspect the food products imported from these cities/provinces.  Mr Leung replied that the reported incidents occurred in various cities/provinces across the Mainland.  FEHD had approached the relevant Mainland authorities for details and follow-up actions, and was informed that so far all the food products involved in the reported incidents did not affect food products exported to Hong Kong.  


26.                                     Mr Leung explained that many of the reported incidents actually involved illegal food factories that produced food products for the nearby cities or villages.  According to previous surveillance results, Mainland food products formally approved for export to Hong Kong generally met Hong Kong��s requirements and standard.  The main concern was those Mainland food products originally destined for the Mainland market and were subsequently introduced into Hong Kong.  These food products might not meet Hong Kong��s food standard and their quality might not be as good as those products formally approved for export to Hong Kong.  


27.                                     Addressing a Member��s question on why different standards were adopted in the Mainland for food products destined for the local market and for export, Mr Leung said that the development of food standard and requirements in different places depended on the local situation and need of different places.  Another Member opined that the food standard in Hong Kong was very stringent and advanced and it was costly for traders to source food products from other places that complied with Hong Kong��s standard.  Dr Mak responded that the Mainland had accorded high priority to upgrade their food safety standard and fully acknowledged the production and hygiene standard of processing plants producing food products for export.  In fact, they intended to gradually upgrade the production standard and quality control of the food products destined for the Mainland market.  


Agenda Item 5 : Study on Dietary Exposure to Mercury of Secondary School Students (A Follow-up Report)


28.                                     The Chairman invited Dr Y Y HO to present the paper.


29.                                     Addressing a Member��s query about the dietary exposure to lead, Dr Y Y HO said that FEHD would conduct another study on this issue later.  


30.                                     A Member asked if the dietary exposure to mercury of secondary students in Hong Kong was high as compared with other countries.  Dr Y Y HO said that the exposure estimate for average secondary school student was lower than the average exposure estimate found in similar studies conducted by other countries.  However, it was noteworthy that many other similar studies did not estimate the exposure to methylmercury and hence the results might not be directly comparable. 


31.                                     Another Member asked if the study results could be translated into simple health advice to the public.  Dr Y Y HO said that as swordfish and tuna had the highest concentration of mercury, it was recommended that pregnant women should not consume more than 2 to 3 pieces of swordfish in sashimi size, and not more than 10-30 pieces of tuna in sashimi size per week.  For ordinary adults, a balanced diet should suffice to avoid an excessive intake of mercury. 


32.                                     Another Member asked if the mercury content of the respective food items covered in the study were publicised at the website.  In response, Dr Y Y HO said that a full report had been uploaded at the website which contained the average mercury content of the six respective food groups covered in study.  However, the mercury content of each sample of food items was not available. 


33.                                     In response to a Member��s query about the types of fish collected for the study, Dr Y Y HO said that various types of fish including those types commonly consumed by general households were covered.  The mercury concentration in the commonly consumed fish types was not found to be alarming and large predatory fish such as swordfish and tuna were found to have the highest concentration.  The Chairman remarked that pollution of rivers could result in high concentration of heavy metal in the fish types whose habitat was in estuarine waters.  Mrs Carrie YAU asked if future surveillance could focus on the fish types commonly consumed by general households.  Mr Leung agreed that targeted study on heavy metal concentration in such fish could be conducted.  A Member remarked that it was worthwhile to conduct such targeted study on a regular basis.  Dr Mak agreed to consider. 

Agenda Item 6: Any Other Business


(a)               Local Human JE cases


34.                                     In response to the Chairman��s query about the epidemiological investigation as to why only one local human JE case was found throughout 2003 and three local cases were already detected up to now this year, Dr Thomas TSANG said that the reason for the increase had yet to be confirmed.  However, there were several possibilities.  Firstly, it might be due to the implementation of a more comprehensive surveillance programme. Starting from 11 June 2004, all Hospital Authority and private hospitals were asked to forward viral Encephalitis cases to the Department of Health (DH) to detect if the cases were JE or not.  Up to now, 20 viral Encephalitis cases were still under testing and there was no geographical concentration of these cases.    Secondly, May to July was a high-risk period for JE and this might explain why more cases were detected during this period.  Thirdly, there might be a possibility that the JE infection pattern of pigs and migratory birds had led to more active Culex Tritaneinorhychus carrying JE virus.  Finally, DH also collected blood samples from local residents living close to the three human cases for serological tests to ascertain JE exposure.  The testing results so far did not reveal any local residents had recently been exposed to the virus.  The antibody prevalence was also similar to previous studies conducted.


35.                                     Addressing the Chairman��s question about the situation in the Mainland and Taiwan this year, Dr Tsang said that there was no upsurge in JE cases in these two places as informed by the relevant authorities there. 


36.                                     A Member asked which kind of mosquito repellent was the most effective.  Dr Y Y HO said that mosquito repellents containing DEET were effective.  Another preventive measure was to wear long-sleeved clothes and trousers when staying outdoor.  


37.                                     Noting that universal vaccination against JE was implemented in Japan, Taiwan and the Mainland, a Member asked whether vaccination was recommended for the high-risk groups.  Dr Tsang said that the Advisory Committee on Immunization had recently held a meeting to consider the pros and cons of implementing a universal vaccination programme against JE in Hong Kong.  The Committee concluded that given the low incidence of the disease in Hong Kong, the demerits of a universal vaccination programme still outweighed the merits.  However, for the high-risk groups, they could consult their private practitioners to consider if they should be vaccinated.  Moreover, DH had also made preparation to keep an adequate stock of vaccine in case of possible JE outbreaks.   Mrs Yau added that a universal vaccination programme was implemented in Japan because of its historical background of having JE outbreaks in 1960s.  The disease situation was controlled after a universal vaccination programme was implemented.  In fact, the Japanese authority was now reviewing the need for such a programme as only some 10 JE cases were detected every year. 


38.                                     The Chairman said that children were usually more susceptible to JE, but all the three local human cases involved adults.  He asked if there was any epidemiological link about the work places of the three patients.  Dr Tsang said that for places with a high JE incidence, children were usually more susceptible as adults could have been exposed to the virus long before.  However, for a low incidence place like Hong Kong where persons below the age of 40 subject to serological tests were found to have little or no immunity against the disease, it was not unexpected for the three cases to be adults.  For the three cases, there was no workplace of the patients concerned.  


(b)               Antibiotic contamination in food


39.                                     A Member asked about the progress of the preparation of a paper on antibiotic contamination of food products which he had suggested earlier.  Dr Mak said that a paper would be prepared for the Advisory Council��s consideration in due course.   


40.                                     There being no other business, the meeting ended at about 4:15 p.m.







Advisory Council on Food and Environmental Hygiene

Health, Welfare and Food Bureau

July 2004