Plastic products have always been a confusing topic.
On the one hand, plastic products are everywhere, and they are cheap, convenient, and not afraid of falling, so you simply cannot live without them; on the other hand, they are chemically synthesized and always look less friendly than ceramics and iron.
How can we reassure the elderly?
First, we can take a look at the qualification rate of plastic products on the market, taking Shanghai as an example.
On September 5, 2016, the Shanghai Municipal Administration for Industry and Commerce conducted random inspections on 29 batches of plastic shopping bags. Among them, 5 batches were unqualified due to falling dart impact (referring to the insufficient strength of the plastic shopping bags and the nominal load). It is easy to break when the weight is heavy) [1]; On September 29, the Shanghai Municipal Bureau of Quality and Technical Supervision announced the results of the 2016 Shanghai Food Plastic Packaging Composite Film and Bag Quality Special Supervision and Spot Inspection. A total of 95 batches of products were randomly inspected, of which 2 The batch of products was unqualified. One was that the oxygen permeability was unqualified (meaning that it tests the air tightness of the plastic packaging bag), and the other was that the total amount of solvent residue was unqualified. [2]It can be seen that most of the plastic products circulating in the market are qualified.
So, what is the basis for the country to set qualification standards? In other words, what aspects of plastic products may have an impact on health?
All plastics are polymers. Just like fragile copper sheets and iron rings can be woven into strong chainmail through special techniques, small molecule compounds polymerize with each other under special circumstances, and then supplemented with corresponding plasticizers, colorants, etc., they become Plastic products with light weight, wear resistance and stable properties.
The health risks of plastics mainly come from two levels.
The polymerization process is not up to standard, and the finished product contains a large amount of monomers that have not participated in the polymerization reaction or oligomers with a low degree of polymerization.
For example, polyvinyl chloride is made from the polymerization of vinyl chloride. PVC is not toxic, but vinyl chloride has an anesthetic effect on the human body and can cause vasoconstriction in the limbs, causing pain. What is even more frightening is that it can form oxychlorine in the liver. Ethylene and vinyl chloride oxide are carcinogenic and teratogenic. [3]
If the vinyl chloride content of finished PVC products exceeds the safe upper limit (1mg/kg), serious consequences may occur. [4]
Therefore, my country has formulated hygienic standards for polyvinyl chloride molded products for food packaging (GB 9681-88), which stipulates the amount of vinyl chloride monomer in finished polyvinyl chloride products. [5]
Post time: 05-23-2024
