Recently, it was revealed that some Taiwan manufacturers of food and drinks use the industrial plasticiser - di (2-ethylhexyl) phthalate (DEHP) as food additives to formulate clouding agents, in an attempt to reduce cost and increase stability of the products. In this issue, Dr Leung Ka-sing, Visiting Associate Professor of PolyU’s Department of Applied Biology and Chemical Technology, will enlighten us on this topic.

1. What is the use of clouding agents in the production of food?

Clouding agents are food additives classified as emulsifiers and are used to form or maintain a uniform emulsion in food. It is usually added to fruit juices or fruit beverages to increase turbidity with a view to providing a natural appearance.

2. How will DEHP affect the human health? Is it a cancer-causing material?

Large doses of DEHP were found to affect the liver and kidney as well as the reproduction and development of experimental animals. To what extent DEHP will affect the human health depends on the intake dosage and duration. At present, there are contradicting schools of thought in whether DEHP will affect the hormones in the human body. It has not been proven, but is possible, that DEHP is carcinogenic to humans.

3. Is there any intake limit of DEHP set internationally, so as not to pose any risk to the human health?

The European Union has set a maximum limit of 1.5 mg/kg for DEHP in food due to migration from food contact material. In Hong Kong, the Centre for Food Safety has set the same maximum limit as an action level.

4. Human beings will take in DEHP through what other channels?

DEHP may be present in food, either due to migration from packaging or food contact materials. Due to its widespread presence as an environmental contaminant, DEHP can be found in air particles and can be taken in by humans through breathing. Dermal exposure is another channel, e.g. humans may be in contact with DEHP-containing cosmetics. In addition, humans will indirectly take in DEHP through the food chain. For example, a cow has DEHP-intake from the environment and then a human being has consumed the cow’s milk.

5. How can we reduce the health risk from phthalate plasticizer?

Animal studies showed that phthalate plasticizers underwent rapid metabolism and most of it and its metabolites were excreted through urine and feces. Therefore, the best way is to maintain a healthy living, such as doing more exercise and have a balanced diet.