Disposable chopsticks found in Singapore are generally safe for use as they do not contain excessive amounts of sulphur dioxide residue, announced the Consumers Association of Singapore (CASE) on Wednesday (7 November)
In a press release, the authority stated that it commissioned a test on 20 samples of disposable chopsticks sold in Singapore for sulphur dioxide residue, which may be harmful to one’s health in excessive amounts. The test results showed less than 400mg/kg of sulphur dioxide found in all samples.
CASE noted that sulphur dioxide is often used as a bleaching agent and to prevent the growth of mould and pests in disposable chopsticks. Excessive sulphur dioxide may negatively affect the human respiratory system. It also reacts easily with substances to form harmful variants, such as sulphurous acid and sulphate particles. People who are allergic to these variants may develop difficulties in breathing and skin allergies.
According to the authority, the 20 samples were selected by random sampling and purchased from departmental stores, supermarkets and stores in the heartland areas.
As a form of control and also because of traceability issues, disposable chopsticks provided for takeaway at cooked food stalls and eateries were excluded, it added.
CASE stated that the test was conducted using a methodology adopted from the Pearson’s Composition and Analysis of Foods (1991). The method included warm water leaching from the sample, followed by titration. The samples were cut into smaller pieces for testing. For every 1 cm of surface area, 2 ml of water was used to soak the samples.
The samples were then soaked at 60°C for 30 minutes. After soaking, the solution obtained was then tested for presence of sulphur dioxide.
According to the test results, a range of residual sulphur dioxide between 7mg/kg and 364 mg/kg was detected in the 20 samples CASE said.
CASE stated that there is no specific standard regulating the amount of sulphur dioxide residue in disposable chopsticks in Singapore. However, it noted that the Guobiao Standards, administered by the Standardisation Administration of the People’s Republic of China, states that sulphur dioxide residue should not exceed 600 mg/kg in disposable chopsticks.
The Taiwan Food and Drug Administration also has a Sanitation Standard for Disposable Chopsticks indicating that the sulphur dioxide residue found in disposable chopsticks should not exceed 500 mg/kg, it added.
Separately, residual substances present in food-contact articles do not pose any food safety concern unless they migrate from the food contact articles into food. Thus, the Singapore Food Regulations, administered by the Agri-Food & Veterinary Authority (AVA), stipulates that all food contact articles do not migrate any harmful substances to the food coming into contact with them.
According to CASE, AVA conducts regular sampling and testing of food contact materials to ensure that they do not release any harmful substances
into food. Currently, disposable utensils used in Singapore meet safety standards for migration and are safe for handling food.
Despite the fact that the chopsticks are generally safe to use, CASE stated that consumers are advised to avoid using disposable chopsticks that look too white as a word of caution. As sulphur dioxide is used as a bleaching agent, disposable chopsticks that appear too white are likely to have been bleached before, thus potentially containing sulphur dioxide. Disposable chopsticks that give off a pungent smell should also be avoided as this may indicate plausible chemical use.
It, however, noted that disposable chopsticks are meant for single-use and consumers are advised not to use them repeatedly