What is dioxane? Where did it come from?
Dioxane, the correct way to write it is dioxane. Because evil is too difficult to type, in this article we will use the usual evil words instead. It is an organic compound, also known as dioxane, 1, 4-dioxane, colorless liquid. Dioxane acute toxicity is low toxicity, has anesthetic and stimulating effects. According to the current Safety Technical Code of Cosmetics in China, dioxane is a prohibited component of cosmetics. Since it is forbidden to add, why do cosmetics still have dioxane detection? For reasons that are technically unavoidable, it is possible for dioxane to be introduced into cosmetics as an impurity. So what are the impurities in the raw materials?
One of the most widely used cleansing ingredients in shampoos and body washes is sodium fatty alcohol ether sulfate, also known as sodium AES or SLES. This component can be made from natural palm oil or petroleum as raw materials into fatty alcohols, but it is synthesized through a series of steps such as ethoxylation, sulfonation, and neutralization. The key step is ethoxylation, in this step of the reaction process, you need to use a raw material of ethylene oxide, which is a raw material monomer widely used in the chemical synthesis industry, in the process of ethoxylation reaction, in addition to the addition of ethylene oxide to fatty alcohol to generate ethoxylated fatty alcohol, There is also a small part of ethylene oxide (EO) two two molecules condensation to produce a by-product, that is, the enemy of dioxane, the specific reaction can be shown in the following figure:
In general, raw material manufacturers will have later steps to separate and purify dioxane, different raw material manufacturers will have different standards, multinational cosmetics manufacturers will also control this indicator, generally about 20 to 40ppm. As for the content standard in the finished product (such as shampoo, body wash), there are no specific international indicators. After the Bawang shampoo incident in 2011, China set the standard for finished products at less than 30ppm.
Dioxane causes cancer, does it cause safety concerns?
As a raw material used since World War II, sodium sulfate (SLES) and its by-product dioxane have been extensively studied. The United States Food and Drug Administration (FDA) has been studying dioxane in consumer products for 30 years, and Health Canada has concluded that the presence of trace amounts of dioxane in cosmetic products does not pose a health risk to consumers, even children (Canada). According to the Australian National Occupational Health and Safety Commission, the ideal limit of dioxane in consumer goods is 30ppm, and the upper limit of toxicologically acceptable is 100ppm. In China, after 2012, the limit standard of 30ppm for dioxane content in cosmetics is far less than the toxicologically acceptable upper limit of 100ppm under normal use conditions.
On the other hand, it should be emphasized that China’s limit of dioxane in cosmetic standards is less than 30ppm, which is a high standard in the world. Because in fact, many countries and regions have higher limits on dioxane content than our standard or no clear standards:
In fact, trace amounts of dioxane are also common in nature. The US Toxic Substances and Disease Registry lists dioxane as being found in chicken, tomatoes, shrimp and even in our drinking water. The World Health Organization Guidelines for Drinking Water Quality (Third edition) state that the limit of dioxane in water is 50 μg/L.
So to sum up the carcinogenic problem of dioxane in one sentence, that is: regardless of the dose to talk about the harm is a rogue.
The lower the content of dioxane, the better the quality, right?
Dioxane is not the only indicator of SLES quality. Other indicators such as the amount of unsulfonated compounds and the amount of irritants in the product are also important to consider.
In addition, it is important to note that SLES also come in different sizes, the biggest difference being the degree of ethoxylation, some with 1 EO, some with 2, 3 or even 4 EO (of course, products with decimal places such as 1.3 and 2.6 can also be produced). The higher the degree of increased ethoxidation, that is, the higher the number of EO, the higher the content of dioxane produced under the same process and purification conditions.
Interestingly, however, the reason for increasing EO is to reduce the irritant of surfactant SLES, and the higher the number of EO SLES, the less irritating to the skin, that is, the milder, and vice versa. Without EO, it is SLS, which is disliked by the constituents, which is a very stimulating ingredient.
Therefore, the low content of dioxane does not mean that it is necessarily a good raw material. Because if the number of EO is small, the irritation of the raw material will be greater
In SUMMARY:
Dioxane is not an ingredient added by enterprises, but a raw material that must remain in raw materials such as SLES, which is difficult to avoid. Not only in SLES, in fact, as long as ethoxylation is carried out, there will be trace amounts of dioxane, and some skin care raw materials also contain dioxane. From the point of view of risk assessment, as a residual substance, there is no need to pursue absolute 0 content, take the current detection technology, “not detected” does not mean that the content is 0.
So, to talk about harm beyond the dose is to be a gangster. The safety of dioxane has been studied for many years, and relevant safety and recommended standards have been established, and residues less than 100ppm are considered safe. But countries such as the European Union have not made it a mandatory standard. The domestic requirements for the content of dioxane in products are less than 30ppm.
Therefore, the dioxane in shampoo does not need to worry about cancer. As for the misinformation in the media, you now understand that it is just to get attention.
Post time: Sep-27-2023
