# The Risk of Using Cosmetics and Cosmetic Procedures During Pregnancy
## 4 The Risks of Cosmetics and Cosmetic Procedures
### Risks of Ingredients of Cosmetics  
Cosmetic products are necessities in human's daily life including pregnant women. Recent studies reported that 60-80% of pregnant women use cosmetic products, including facial cleansers, day cream, foundation, mascara, lipstick, eye pencil, eye shadow, and make-up remover. These products contain various chemical substances (e.g., parabens, formaldehyde, titanium dioxide, nitrosamine, phenol, and organic solvents) and heavy metals, which are either added purposely as efficacy components to enhance the skincare effect of cosmetic products or brought in through the raw materials, auxiliary materials, or technical problems during the production process [41]. Also, cosmetics are a significant tool for many professional aestheticians. Previous studies indicate that aestheticians who are constantly in contact with cosmetics have two to four times more exposure to toxins compared to those who use cosmetics intermittently. Over 10,000 chemicals are used in cosmetics, but many are not completely harmless [42]. Numerous synthetic chemical ingredients should be avoided due to their toxicity. Toxic substances are those capable of destroying life [43]. When toxic substances enter the body, they are metabolized in the liver, where they are inactivated and then excreted by the kidneys or bio accumulated [44]. The most common dangerous chemicals used in cosmetics include the following:  
* Acetone: This solvent, used in nail polish removers, can cause dry mouth, dizziness, nausea, difficulty speaking, and, in extreme cases, coma. It acts as a central nervous system (CNS) depressant [45]. * Aluminum Compounds: Commonly found in deodorants and antiperspirants, aluminum compounds can block sweat glands and pores, preventing the body's natural sweating process. There are concerns that these compounds may be linked to breast cancer, breast cysts, and Alzheimer's disease. However, the dermal absorption of aluminum is not well understood, and it is not yet known whether aluminum can travel from the skin to the brain to cause [PERSON]'s disease. While aluminum may cause gene instability, alter gene expression, or enhance oxidative stress, its carcinogenicity has not been proven. Epidemiological research on aluminum exposure has been inconsistent and conflicting [46; 47]. * Ammonia: Found in many cosmetics, ammonia can cause allergic reactions and, with long-term exposure, may lead to coughing, respiratory arrest, and pulmonary edema, potentially resulting in death [48]. * Titanium Dioxide: Commonly used in sunscreens and toothpastes, titanium dioxide can be absorbed through the skin or inhaled during manufacturing and use. Despite its extensive use, the biological effects and cellular response mechanisms of titanium dioxide nanoparticles (TiO\({}_{2}\)-NPs) are not fully understood. The toxicity of TiO\({}_{2}\)-NPs appears to involve reactive oxygen species (ROS) production, leading to oxidative stress, inflammation, genotoxicity, metabolic changes, and potential carcinogenesis. The extent and type of cell damage depend on the chemical and physical characteristics of TiO\({}_{2}\)-NPs, including size, crystal structure, and photo-activation [49]. * Diethanolamines (DEA): Used mainly as surfactant foam boosters or viscosity increasing agents, DEA can cause allergic reactions and eye and skin irritation and is a potential carcinogen if used in the long term. Recent reports have raised concerns about an increase in allergic dermatitis associated with DEA [50]. Also, older studies in animals have found a link between maternal exposure to DEA and altered memory function in offspring [51]. * Mineral Oil: Found in many creams for eyes, lips, and hydration, mineral oil forms a barrier on the skin that can prevent it from breathing, expelling toxins, hydrating, and producing healthy cells. Common reactions include premature skin aging, cardiac disorders, kidney and liver damage, and breathing difficulties [43]. * Parabens: Parabens in cosmetics are very common and humans use them in daily life.