In reality, there is no absolute poison and there is no absolute harmless substance. Harmful or harmless depends to a large extent on the dose of exposure, the duration of exposure and the manner of exposure. As early as the late 1970s, the U.S. FDA began monitoring the dioxane content in cosmetics. From 1992 to 1997, the FDA monitored dioxane levels of 79 ppm in some cosmetics, but the FDA did not believe that this level would be a health hazard to consumers. Acute toxicity tests for dioxane are in the slightly toxic category. Rats ingested dioxane orally, half of the experimental animals lethal dose of 5170mg/kg; rabbits percutaneous half of the experimental animals lethal dose of 7600mg/kg; rats respiratory inhalation 2 hours, half of the experimental animals lethal dose of 46000mg/m3. The carcinogenicity of dioxane for human beings under the same dose condition is inconclusive. In comparison, the current content of dioxane in bathroom and shampoo products is indeed very low. The official website of the Australian Health Administration’s technical document on the assessment of dioxane and the recommended standards consider that the ideal limit of dioxane is 30 ppm in everyday consumer products, except for food and pharmaceuticals, and that it is toxicologically acceptable when the content does not exceed 100 ppm. Modern medical research can determine the toxicological characteristics of a single substance, and then guide and regulate people’s production and consumption behavior. And when people are exposed to a variety of chemical substances at the same time, between chemicals in the category of toxic expression, whether the effect of adding, subtracting or multiplying, is a difficult problem to crack worldwide. A shampoo product, there are reports that can include dozens of chemicals, or even more. General shampoo roughly contains surfactants, conditioning agents, hair conditioners, moisturizers, emulsifiers, viscosity adjusters and so on, and each category has a number of substances to choose from, companies will be the product formula as a trade secret, the average consumer is difficult to meticulous detail. In view of this, the National Standards Committee promulgated the “General Labeling for Consumer Products Instructions for Use Cosmetics”, which requires that all ingredients must be labeled for cosmetics produced after October 1, 2009. The relevant national policies, regulations and technical specifications are usually broad-brush. If a commercially available product merely states “whitening introduction factor”, “natural plant-derived ingredients”, “vitamin nourishing formula” or English labeling, the majority of consumers are still The majority of consumers are still “looking at the flowers in the fog”, and it is difficult to know the true nature of the mountain. Out of compliance with national policies and regulations, in order to protect the legitimate rights and interests of consumers, the manufacturer has the responsibility to clearly label the name of the main ingredients in Chinese. And labeled “all ingredients”, in technical terms, almost unfeasible. Such substances are theoretically unlimited, because any substance that exists in the natural environment can be found in any product, even in the human body, only in different doses. It is true that I, as a clinician, have not, to date, seen any patients whose shampoo use has resulted in poisoning or tumors. In the field of clinical medicine, or in people’s daily lives, there is actually a problem of following different levels of health “protection”. For example, there are significant differences in health care behavior, psychological burden and medical expenses for different patients with the same disease. Once a consumer who uses bathroom or shampoo products learns that the product he uses contains dioxane, it will lead to different consumer behavior choices and psychological burdens for the consumer, even though the national authorities have concluded that it is not harmful to health. Relevant studies have confirmed that commercially available bathroom and shampoo products certified by quality management departments have basic guarantees for people’s health and consumers can use them with confidence. However, safety and health is always a relative concept, there is no absolute. In the bathroom, shampoo products today, any product is a collection of numerous ingredients, just focus on dioxane can not solve all the problems. A domestic study reported that three different brands of commercially available shampoos were selected to observe the genotoxic effects on the root tip cells of broad beans, and the results showed that the root tip cells of broad beans were mutagenized by three shampoos to produce various types of chromosomal aberrations, indicating that the tested shampoos had genotoxic effects on the root tip cells of broad beans. Broad bean root tip cells are not equivalent to the human body. I was asked by a media reporter what happens when consumers use shampoo and conditioner and rinse them out or do not rinse them out. I don’t think I would see any difference in the presenting clinical condition. If you read about the genotoxicity of shampoo on the root tip cells of broad beans – which is a combined effect of multiple substances – and are concerned about it, it is better to rinse out the shampoo and conditioner after showering.