Frequently Asked Questions
1. What is melamine?
Melamine (also known as tripolycyanamide) is an industrial chemical used for the production of melamine resins, which are used in laminates, glues, adhesives, molding compounds, coatings, paper, textiles, flame retardants or superplastisizer for concrete.
2. How did melamine get into infant formula?
The adulterant melamine was added to milk to cause a false increase in the measurement of protein for dairy products. It is not allowed to be added to food in any quantity.
3. What is the toxicity of melamine?
Melamine has low oral acute toxicity. However, excessive exposure to melamine has been found to cause urinary stones in experimental animals. Laboratory studies showed that melamine did not damage genetic materials in cells. There was also inadequate evidence to show that melamine can cause human cancers.
4. How were infants being affected by melamine containing infant formula?
Recently, tens of thousands of infants in the Mainland who have consumed Sanlu infant formula are suffering from renal disease, including urinary stones, conditions of which are rare in infants. Infants are more susceptible to urinary stones formation because milk is their major food, the amount of melamine intake per body weight is much higher than that of adult who consumes a variety of foods. Also, it was found that Sanlu infant formula contained especially high level of melamine (up to 2563 mg/kg) that may affect the elimination of the chemical from the body.
5. What are the clinical presentations of the development of urinary stone after the consumption of melamine containing infant formula in infants?
The clinical presentations included irritability, blood in urine, little or no urine, stone in urine, pain and difficulty in urination, and high blood pressure etc.
6. How are adults being affected by the consumption of melamine containing milk?
Based on Mainland’s situation, over 99% of victims affected by consumption of melamine containing milk were below three years old. As the sensitivity towards melamine is lower and milk is not a major food source of adults, the health risk of adults in consuming melamine containing milk is lower.
7. What are the health effects of melamine to pregnant women and fetus?
Based on Mainland’s situation, over 99% of victims affected by consumption of melamine containing milk were below three years old. There is currently no human data available on the health effects to pregnant women and fetus. Available animal studies did not show evidence that it would produce defects in developing fetus.
8. What are the health effects of melamine to elderly?
Based on Mainland’s situation, over 99% of victims affected by consumption of melamine containing milk were below three years old. There is currently no human data available on the health effects of melamine to elderly. However, milk only constitutes a part of the total food consumed by the adult population and the risk is relatively low.
9. What are the health effects for consumption of food containing melamine for a long period of time?
There is currently no human data available regarding consumption of food containing melamine for a long period of time. Information based on data from animal studies showed that melamine is rapidly cleared from the body. However, based on Mainland’s information, over 99% of victims affected by consumption of melamine containing milk were below three years old; majority of them was affected three to six months after the consumption of contaminated milk.
10. What products were found to contain melamine in the Mainland?
The list of products that were found to contain melamine and their manufacturers is posted on the website of the General Administration of Quality Supervision Inspection and Quarantine of People’s Republic of China. Consumers can check with the official website for updated information.
11. Are those melamine contaminated infant formula including the Sanlu formula and those formula tested with melamine by the Mainland available in Hong Kong ?
No, they are not found to be available in Hong Kong . People who have purchased the product outside Hong Kong should stop consuming the product immediately.
12. Has melamine been found in any infant formula, other dairy products or food products available locally?
Since mid-September 2008, the CFS has taken from the local market samples of infant formula and other milk-made products, such as fresh milk, ice-cream, ice-cream bars, yogurt, baby food, nutrition supplements for hospital use, instant drink mixes, biscuits, cakes, bread, chocolate and candies etc. for tests. The CFS has, on the recommendation of the Expert Group on Melamine Incident, expanded the food sampling plan to include food raw materials (e.g. eggs), meat and vegetables in the second phase of testing. Upon the conclusion of the second phase of testing on 16 November 2008 , the CFS has entered into the third phase since 17 November 2008 , in which samples of food types found unsatisfactory in the previous two phases have been retaken for testing. As at 23 December 2008 , a total of 40 samples of 18 brands of food products were found to contain unsatisfactory amount of melamine ranging from 1.4ppm to 68ppm. The sample results are available in the web site of CFS, www.cfs.gov.hk. The highest level of melamine was detected in one biscuit sample. All the affected products have been off shelves and withdrawn from the market. CFS will continue to monitor the situation closely.
13. How much of the food that exceeded the legal limits for melamine one has to consume before the safety reference value is exceeded?
According to the information of US Food and Drug Administration (USFDA) in September 2008, the tolerable daily intake (TDI), i.e. the safety reference value for melamine is 0.63 mg per kg of body weight per day. Since children under three are more sensitive to melamine, safety reference value is set at 0.32 mg per kg of body weight per day for children under three by CFS. For the details on the amount of food a person has to consume daily before the safety reference value is exceeded, you may click onto the link. As the susceptibility to melamine differs between young children and adults, we have included two sets of limits (a three-year-old child with 10 kg body weight and an adult with 60 kg body weight) as examples. However, transient excursion above the safety reference value of melamine would have no health consequences provided that the average intake over a long period has not exceeded the safety reference value.
Subsequently, the World Health Organisation (WHO) announced on 5 December 2008 that the TDI for melamine was established at 0.2mg per kg of body weight per day.
14. What is the advice to consumers?
Caregivers should not feed infant formula or other milk products that were contaminated with melamine to infants and young children. Individuals should seek medical advice if they have urinary symptoms including the development of urinary stone and with history of exposure to melamine containing dairy products.
15. How can the public get information on food products contaminated with melamine?
Public can call CFS's telephone hotline at 2381 6096 (Monday to Friday: 9:00 am to 6:00 pm ) for enquiry. There will be no service on Saturday, Sunday and public holiday. Public can also refer to CFS's website for the updated test results of the food product samples.
16. What is the legal limit for melamine in food in Hong Kong ?
Under the amended Harmful Substances in Food Regulation (Cap. 132 AF), milk, any food intended to be consumed principally by children under the age of 36 months and any food intended to be consumed principally by pregnant or lactating women shall not contain melamine exceeding 1 mg/kg. For other food, melamine level shall not exceed 2.5 mg/kg.
17. Can the enforcement limits of melamine in food protect public health?
WHO announced on 5 December 2008 that the limits for melamine in infant formula (1mg/kg) and in other food (2.5mg/kg), same as the limits that we adopted, provide a sufficient margin of safety as compared to the TDI. The health of children and adults will not be affected upon consuming foods that comply with the enforcement limits. For melamine intake, occasional excursion above the safety reference value would have no health consequences provided that the average intake over a long period does not exceed the value.
18. How about limits for melamine set by other food safety authorities?
As of 10 December 2008 , Mainland China and many food safety authorities of developed countries have established limits for melamine in food :
The Ministry of Health of the Mainland has established interim limits for melamine in infant formula and follow-up formula at 1 mg/kg; liquid milk (including raw milk), milk powder and other formula at 2.5 mg/kg; and other food containing more than 15% of milk at 2.5 mg/kg.
The European Commission requires that any products originating in or consigned from China containing milk,or milk products, soya or soya products should be subject to documentary, identity and physical checks, including laboratory analysis, to determine that any levels of melamine present in the product do not exceed 2.5 mg/kg.
The Food Standards Australia New Zealand (FSANZ) considers that a maximum level of 1 mg/kg for melamine in infant formula and a maximum level of 2.5 mg/kg for melamine in dairy-based foods and foods containing dairy-based ingredients are appropriate.
The New Zealand Food Safety Authority (NZFSA) sets the limit of 2.5 mg/kg for most foods (final form) before regulatory action is considered. For infant formula, this level is set to the level of test detection of 1 mg/kg.
Health Canada sets a maximum level of 0.5 mg/kg for melamine in infant formula and sole source nutrition products, including meal replacement products and a maximum level of 2.5 mg/kg in other food products containing milk and milk-derived ingredients.
The US Food and Drug Administration (FDA) indicates that food, other than infant formula, with levels of melamine and melamine-related compounds below 2.5 mg/kg do not raise public health concerns. For infant formula, levels of melamine below 1.0 mg/kg also do not raise public health concerns.
19. Why doesn't CFS report the melamine levels of the satisfactory products?
Currently, food products including milk, food intended to be consumed principally by children under the age of 36 months, pregnant or lactating women containing melamine at levels below 1 mg/kg and other food containing melamine at levels below 2.5 mg/kg are considered satisfactory. Food products containing melamine below these levels should present no health risk to the public. Quantifying and reporting the melamine levels of these satisfactory food products require additional resources and take longer laboratory testing time. The Expert Group on Melamine Incident set up by the Government in end September 2008 opined that at that juncture, resources should be utilized to examine more high risk foods rather than on checking levels below the regulatory limit of 1 mg/kg. The public is assured that consumption of food products meeting the regulatory limits would not put their health at risk. Both children and adults are well protected by the local enforcement limits.
20. Will there be any risk if all the foods we consume everyday contain melamine at the levels just below the legal limits?
When the regulatory standards were set, we have taken into consideration the scenario that all the foods we consume everyday contain melamine at the levels just below the legal limits. A margin of safety has also been built in. The legal limits for melamine are 1 mg/kg for milk, any food intended to be consumed principally by children under the age of 36 months and any food intended to be consumed principally by pregnant or lactating women and 2.5 mg/kg for other food. Based on the best available science and results of risk assessment, there is no risk to public health even if all the foods we consume everyday contain melamine at the levels just below the legal limits.