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  • 1996.09.14
  • Excessive hydrogen peroxide found in tooth whitener
  • Hygiene condition of some of the sandwiches alert for potential public health hazard 
  • Price survey on primary and secondary school textbooks
  • Multi-layer (or Sandwich-base) cookware hurts consumer
  • Is colorless lipstick safe ?
  • Protect the environment, use less plastic bags
  • Complaints on unsafe toys
  • Treatment of corns
  • Keep slopes safe
  • Price survey on residential flats in Hung Hom

Sandwiches may be a fast and efficient solution to the problem of lunch time rush for restaurants. But the hygiene condition of some of the sandwiches sold at fast food outlets and bakeries in Hong Kong, is far from totally satisfactory.

This alert for potential public health hazard was raised in a test report of the Consumer Council, released today in its 'CHOICE' magazine, on the hygiene condition of 20 sandwich samples.

The samples, comprising both prepackaged and freshly made tuna fish, chicken and ham and egg sandwiches, were sourced from 11 different fast food restaurants and bakeries at busy locations.

According to the test, only 5 samples scored a straight grade A in all test items. The test results were assessed against the "Microbiological Guideline for Sandwiches" adopted by Department of Health which divides the standard into four gradings: A (Satisfactory), B (Acceptable), C (Unsatisfactory), and D (Unacceptable /Potentially Hazardous).

The majority of the remainder samples received a mix of A and B grades indicating that their hygiene condition while not completely satisfactory was "Acceptable" in some test items.

4 samples, however, failed poorly with grades C and D indicating that their hygiene condition was below standard.

One sample was found to be "Unsatisfactory" in all test items relating to the level of Total Bacterial Count (TBC), E. Coli and Staphylococcus aureus.

(E. Coli is commonly found in feces; some strains of E. Coli are not harmful to health while some may cause diarrhoea and vomiting. Staphylococcus aureus is due to human contamination of food through skin infections and symptoms include abdominal cramps, vomiting and diarrhoea.)

Another sample was judged to be "Unacceptable/Potentially Hazardous" in the E. Coli count with 110,000 per gram exceeding the "Acceptable" level of 100 by1,100 times! The same sample was also "Unsatisfactory" in its TBC test.

The remaining 2 samples were graded "Unsatisfactory" in the TBC and E. Coli tests respectively.

Contamination of the two pathogens, Clostridium perfringens and Salmonella, was not detected in all of the sandwich samples.

The Department of Health issued a new hygiene guideline on sandwiches last month while the Consumer Council was in the process of compiling the test findings.

The new guideline which the Council used to present the test results, is understood to facilitate the Department in its enforcement action.

The findings of the test indicated that there is still room for improvement in the hygiene condition of some sandwiches on public sale.

Unlike spoilage bacteria, food poisoning bacteria such as Staphylococcus aureus does not alter the taste or appearance of the food. Without laboratory testing, consumers are unable to detect if the food is contaminated with this specific pathogen.

Food manufacturers and handlers are requested to improve their quality control system, maintain strict personal hygiene practice, and minimize contact with food by wearing gloves and using tongs for fillings.

Consumers, on the other hand, are advised to purchase prepackaged sandwiches that are properly stored in temperature below 4℃ and labelled with "Use By Date".

For made-to-order sandwiches, consumers are advised to observe the hygiene condition of the shop, i.e. proper food storage below 4℃, whether raw and cooked food are kept apart, and whether food preparers used gloves or tongs when directly handling food.

In the same test, the Council also investigated 7 sushis - 6 prepackaged, 1 freshly made - on their hygiene condition.

The test results affirmed the recent findings on the analysis of sushi samples by the Department of Health. More than half of the samples (5 out of 7) had problem with theTotal Bacterial Count ranging from 130,000 to 13,000,000 per gram.

The controversy over hydrogen peroxide is back in the limelight.

This time it's with the product tooth whitener that claims to whiten your teeth by a chemical bleaching method.

A Consumer Council test has detected the presence of hydrogen peroxide as an active ingredient in these products. Included in the test were samples drawn from the toothpaste type, the soak-and-bleach type and the spread-and-bleach type.

Concentration of 2.6% to 10.4% of hydrogen peroxide was found in all of the 7 test samples.

These levels are grossly in excess of the 0.1% limit under the EEC Directives relating to cosmetic products, by 26 to 104 times.

Excessive hydrogen peroxide in oral hygiene products may pose potential health risks to the users.

The chemical may cause transient sensitivity of teeth temporarily (less than 48 hours) due to irritation of pulpal enzymes. It may also cause inflammation, swelling and bleeding of the gum.

Accidental ingestion of excessive hydrogen peroxide may result in a sudden generation of large amount of oxygen gas, causing the stomach to expand rapidly that may induce symptoms of nausea, vomiting and internal bleeding.

The Hong Kong Dental Association has advised against the use of over-the-counter tooth whiteners as the potential hazards from misuse outweigh their benefits.

Consumers are advised to use such products under strict professional guidance. They should be prescribed by dentists who are knowledgeable about their proper use and capable of handling any complications that may arise.

In the US, the Food and Drug Administration (FDA) is now further evaluating the status of tooth whiteners to determine if they should be regulated as "new drugs" or as cosmetics. As "new drugs", they must possess adequate scientific data, including clinical trials, to establish that the product is safe and effective for its intended use.

The Council's test report also revealed that the trays enclosed with the soak-and-bleach type tooth whiteners are often ill-fitting. Prolonged wearing of such trays may result in an increased unnecessary leakage of the bleaching agent into the oral cavity as well as hinge joint disorder.

The report noted that tooth whiteners may be useful in the removal of extrinsic staining such as those from tea and coffee but they may not respond to intrinsic staining such as fluorosis and dental caries.

A Consumer Council price survey on primary and secondary school textbooks this year has recorded an average increase rate of 12.11% and 11.30% respectively.

This compared with this year's annual inflation rate of 6.9%.

The annual price survey was based on data from 25 primary and 48 secondary schools in Hong Kong.

Despite the price increase, the overall expenditure for primary school textbooks dropped by 0.23%. This is due to the amalgamation of 3 subjects (Social Studies, Science and Health Education) into 1 subject (General Studies).

But the overall expenditure for secondary school textbooks was up by 12.55% compared with last year.

As textbooks were chosen by teachers/schools rather than by parents/students, it is important that to reduce the burden of the latter, certain steps should be taken in the choice of textbooks :

  • The publisher must provide the list price of textbooks to the Education Department so that the price can be printed on the "List of School Textbooks Recommended by the Textbooks Committee" for the reference of schools.
  • In choosing the suitable textbooks, apart from the contents, the teachers should compare also the price of a textbook from different publishers.
  • Teachers should add workbooks/exercises according to their necessity and usage rate and should also take due consideration of the increased expenditure.
  • Schools should allow students to use the old edition textbooks. Publishers, on the other hand, must provide information comparing between the new edition and old edition to facilitate both teachers and students to easily follow.
  • The Education Department should require publishers to print both the publishing date and the printing date on the textbooks so that students will know what product they are purchasing.

Parents/students are also encouraged to shop around as some bookshops offer a discount rate of more than 5% - some as low as 15%.

Use sandwich-base stainless steel cookware with caution. Do not heat the pot when empty.

The aluminium inside the two layers of stainless steel that surround it, can melt and cause severe burns.

The aluminium is used as the metal conducts heat faster and more uniformly than normal stainless steel cookware.

This warning was issued in the wake of a complaint to the Consumer Council. The complainant accidentally overheated the sandwich-base stainless steel cookware when empty.

This caused the aluminium in the base to melt. The cookware was swiftly removed from the electric stove as soon as the complainant saw the accident.

The molten aluminium had, however, dripped down and burned her foot. A big hole was also burnt in her slipper.

Although there was a warning of "Do not heat when empty" in the instruction leaflet, such warning failed to give the reason for not heating the cookware when empty and also to advise the consumers the procedures to follow when such accident happens.

The Council has suggested the manufacturer to enhance the warning with the following: “Do not heat when empty as the aluminium can melt and cause severe burns. If the cookware 'boils dry' and melts, turn off the heat; do not pick up the cookware until it cools".

Sandwich-base cookware is not to be confused with five layers stainless steel cookware which does not have the problem of dripping down hot molten aluminium as the whole cookware is made up of five layers, not just the base.