化妝品中的環戊矽氧烷(十甲基環戊矽氧烷):安全嗎?

cosmetic use

Deciphering the long chemical names on the labels of your favorite cosmetic products can be frustrating. Simple ingredients like water and alcohol are easy to identify. But lengthy chemical names can leave even the most conscious consumer scratching their heads.

Cyclopentasiloxane (D5) is used in hundreds of cosmetic products. In the past, there has been controversy over its potential health and environmental risks. But the Cosmetic Ingredients Review Expert Panel considers it safe for use in cosmetics. However, in early 2018, the EU implemented restrictions on the use of D5 in cosmetics that are designed to be washed off before evaporation. Wash-out products in concentrations above 0.1% have been identified as having a risk of accumulation in water supplies.

Based on clinical studies and reports, cyclomethicone is considered safe for use in cosmetic ingredients because they are not significantly absorbed through the skin.

However, as silicones, they are not natural ingredients, so if you only use natural ingredients on your face and skin, you may want to double-check the ingredients in your products.

What is cyclopentosiloxane?

Cyclopentasiloxane is a type of silicone often used in cosmetics. It is commonly found in medical implants, sealants, lubricants and windshield coatings.

D5 is colorless, odorless, non-greasy, and as thin as water. It is not absorbed into the skin. Instead, it evaporates quickly. This property makes it a useful ingredient in cosmetics that need to dry quickly, such as antiperspirants and hair sprays.

It also has lubricating properties. When applied to skin and hair, it creates a smooth, silky feel and makes the product easier to apply.

What are the benefits of cyclopentosiloxane in skin care products?

D5 is known for its ability to evaporate and dry quickly. Silicone is also known to repel water and slide easily. This is why they are often used as ingredients in lubricants and sealants.

Once applied, D5 has a silky texture that creates a protective barrier for skin and hair. Cyclopentasiloxane in hair products may help prevent breakage, detangle and reduce frizz.

They also form a protective barrier on the skin and hair. This can help detangle your hair, prevent breakage, and reduce frizz.

Here are some potential benefits of products containing D5:

Seals hydration. When used on hair, D5 coats the hair shaft and prevents moisture loss. The compound works similarly on the skin by forming a barrier that locks in moisture.
Evaporates quickly. D5 is commonly used in cosmetics and health and beauty products that require faster drying times.
spreads easily. Like other types of silicones, Decamethylcyclopentasiloxane in Cosmetics applies and spreads easily, leaving a silky-smooth texture and non-greasy finish.
There is a feeling of lightness. Some silicones are heavy, but the D5 feels very light. This property is particularly useful in products such as hair gels and shampoos.

D5 can be found in a variety of personal care products. Examples include:

  • Hair spray
  • sunscreen
  • Antiperspirants
  • Deodorant
  • conditioner
  • shampoo
  • hair loss products
  • waterproof mascara
  • Base
  • eyeliner
  • Concealer
  • SPF moisturizer
  • eye shadow
  • Hair gels and lotions
  • lipstick

It is sometimes shown on labels as decamethylcyclopentasiloxane or D5. It can also be classified under the broader category name cyclomethicone.

It is different from another type of siloxane called polydimethylsiloxane or polydimethylsiloxane (PDMS).

Is cyclopentasiloxane generally safe to use?

One of the main benefits of D5 is that it is less expensive compared to similar ingredients. This helps reduce the cost of your favorite products. Of course, the lower cost means manufacturers have an incentive to use it instead of other ingredients, regardless of its safety or environmental impact.

Like other synthetic ingredients, cyclopentosiloxane has a bad rap in the skin and hair care world because it is not considered a natural ingredient. This compound's bad reputation is partly a misconception.

As long as they are safe to use, some artificial ingredients are better for the environment because they are not derived from natural, plant or animal sources. However, since D5 is silicone, this does mean that it won't break down over time.

What products should you use cyclopentosiloxane with?

It works well with heavier silicones or oils because the compound makes them spread more easily.

What should you not use cyclopentosiloxane with? D5 actually works well with most types of ingredients. The only problem is that it's not natural, so if you tend to choose mostly natural products, any product containing D5 may not be suitable for you.

Whether you know it or not, you may already use several products that contain cyclopentasiloxane.

Here are 6 examples of top products that may contain D5:

  1. hair loss products
  2. waterproof mascara
  3. Base
  4. Hair spray
  5. shampoo
  6. body lotion

Safety issues for human use

The Environmental Working Group (EWG) found that concerns about D5, which is considered an endocrine disruptor, or something that interferes with the normal function of hormones, are low. It can be more concerning when it is used in concentrations higher than those typically used in cosmetics. The Cosmetic Ingredients Review Expert Panel has deemed the chemical safe to use at existing concentrations.

To become an endocrine disruptor, a chemical must enter the body. A 2012 study published in the International Journal of Toxicology found that D5 is not absorbed through the skin. A 2016 study confirmed that it evaporates quickly upon contact with the skin, with very few chemicals entering the body.

If inhaled, it is either quickly exhaled or breaks down and is excreted in urine. This means the chemical is less likely to accumulate in the body.

D5 has also not been found to cause skin irritation or allergy in humans. When used in sunscreen and lotion, studies show it can even prevent irritation in people with skin conditions like rosacea.

Environmental hazard

There is some controversy surrounding the environmental impact of this ingredient. When chemicals used in hair and skin products are flushed down the drain, they enter the environment. These products can accumulate and harm fish and other wildlife.

Cyclopentasiloxane was once considered harmful to aquatic wildlife. It has been found to bioaccumulate in some aquatic animals in laboratory studies. This prompted the Canadian Review Board to conduct more research into the environmental impacts of this chemical.

A 2011 review concluded that the D5 posed no danger to the environment. The review board found no evidence of toxicity to any organism. The committee also found no evidence that the chemical could accumulate to high enough concentrations to cause problems for animals.

A 2013 study found that the chemical evaporates during typical use. Only a tiny fraction of chemicals enter the environment through sewers. The study authors consider this amount to be negligible.

Contrary to earlier studies, a recent EU assessment of the environmental accumulation of D5 has limited the concentration for use in rinse-off cosmetics to less than 0.1%, effective January 31, 2020.

What are the side effects of cyclopentosiloxane?

Cyclopensiloxane has no known side effects and is generally well tolerated. However, as with any new product you try, it's best to test it on a small area of ​​your skin before you try it and apply it all over your body .
Because cyclopentosiloxane spreads easily and leaves a good feel on the skin, it's often mixed with heavier silicones or oils, so be aware of hidden ingredients in D5 that you may not want to show up on your skin.
Although there are no known health side effects from using products containing D5, they may have a negative impact on the environment. Like other types of silicones, cyclopentosiloxane can take years to decompose.

Restricted in the EU

Main changes

In 2015, the Scientific Committee on Consumer Safety (SCCS) stated that levels of cyclotetrasiloxane (D4), an impurity in cyclopentasiloxane (D5), should be kept as low as possible due to its potential toxicity.

In early 2017, the European Commission (EC) proposed a ban on the use of 0.1% or more of cyclotetrasiloxane (D4) and cyclopentasiloxane (D5) in rinse-off cosmetics . The ban will cover shampoo, conditioner, body wash and other products when officially announced.

The European Chemicals Agency (ECHA) plans to go a step further and extend the restrictions to personal care products that are left on the skin. The proposal is currently under public consultation.

Why limit these ingredients?

Cyclotetrasiloxane (D4) is toxic to the human reproductive system and can accumulate in the environment with unpredictable long-term effects. Cyclopentasiloxane (D5) may also be harmful to the environment.

The main issue is the purity of the silicone - or lack thereof. The harmful cyclotetrasiloxane (D4) is a common occurrence of cyclopentasiloxane (D5) impurities and can be difficult to distinguish between them.

What does the manufacturer need to do?

  • Make sure your raw material supplier provides you with the highest purity (99%) cyclopentasiloxane (D5) and no cyclotetrasiloxane (D4)
  • As a precautionary measure - plan to reformulate rinse-off cosmetics with cyclopentosiloxane by reducing the amount to 0.1% or replacing it with another type of silicone

EU restrictions on cosmetic ingredients

Cosmetic ingredients have always been monitored by the Scientific Committee on Consumer Safety (SCCS) and regulatory authorities. The aim is to assess their safety and establish limits to protect human health. Silicones have recently appeared on the scene. Attention has now turned to one of the most widely used types - cyclopentosiloxane. Cosmetic manufacturers and their responsible persons should pay close attention to SCCS updates and track revisions to relevant regulations to make the right decisions to ensure the compliance of their products on the EU market.

Common user concerns

  • One or more animal studies have shown tumor formation at moderate doses
  • Allergy and immunotoxicity
  • Developmental and reproductive toxicity
  • Usage restrictions
  • One or more animal studies have shown any effects at moderate doses
  • One or more animal studies show endocrine disruption at moderate doses
  • Persistence and bioaccumulation
  • Non-reproductive system toxicity
  • Suspected to be an environmental toxin, persistent or bioaccumulative

Summary

Products containing cyclopentasiloxane are safe to use on your hair and skin with minimal personal risk. It helps your skin and hair products dry quickly and spread more easily. It leaves hair feeling silky without weighing it down.

While there are concerns that this ingredient could disrupt hormones in your body, research shows that it doesn't get absorbed into the skin in high enough doses to cause harm.

D5 may accumulate in water supplies when the concentration is above 0.1% and is washed away before evaporation. This possibility has led to increased regulation of its use in some countries.

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