uterine fibroids 子宫平滑肌瘤
Common chemicals called phthalates 邻苯二甲酸酯；邻苯二甲酸盐 found in hundreds of household products have been linked to uterine fibroids 子宫平滑肌瘤—non-cancerous tumors 良性肿瘤 ranging from the size of a seed to a soccer ball that grow in or around the uterus 子宫. These fibroids affect millions of women and can cause pelvic and back pain 骨盆和背部疼痛, heavy menstrual bleeding, pain during sex, or reproductive problems.
Phthalates are known to interfere with hormones and have been the subject of health research for over a decade. Several studies have identified greater risks of fibroids among women exposed to these chemicals. In a 2017 analysis of five studies, researchers from China found increased risks of fibroids in women with escalating levels of byproducts of one phthalate called DEHP—a chemical that’s commonly added to plastics to make them flexible—in their urine 女性尿液中邻苯二甲酸酯(一种被称为dehp的化学物质，通常被添加到塑料中以使其具有弹性)的副产物水平不断上升，从而增加了患肌瘤的风险. In a 2019 preliminary study, Ami Zota, an environmental health scientist now at the Columbia University Mailman School of Public Health, and her colleagues found that higher levels of phthalates in urine, particularly byproducts of DEHP, were associated with larger fibroids and an enlarged uterus in Black women in the United States undergoing surgery for fibroids. 在接受肌瘤手术的美国黑人女性中，尿液中邻苯二甲酸盐含量较高，尤其是DEHP的副产物，与较大的肌瘤和较大的子宫有关。
In the U.S., an estimated 26 million women between the ages of 15 and 50 have uterine fibroids, and more than half of them will experience its debilitating 使衰弱的 symptoms. Currently there are no medications that can permanently reduce the size of the tumor. These tumors can shrink on their own, particularly after menopause, and many women may not need treatment unless the symptoms become hard to manage.目前还没有一种药物可以永久减小肿瘤的大小。这些肿瘤可以自行缩小，特别是在绝经后，许多女性可能不需要治疗，除非症状变得难以控制。
Some medications can alleviate the symptoms, but surgery is the only option when the drugs prove ineffective or the fibroids make it hard for a woman to get pregnant. 一些药物可以缓解症状，但当药物无效或子宫肌瘤使女性难以怀孕时，手术是唯一的选择。
Patients can opt for treatments like a myomectomy to surgically remove the fibroids, which can be minimally invasive and preserve the uterus, but in certain situations a hysterectomy to remove the uterus becomes necessary. 患者可以选择像子宫肌瘤切除术这样的治疗方法，通过手术切除肌瘤，这可以是微创的，并保留子宫，但在某些情况下，子宫切除术切除子宫是必要的。
Even though uterine fibroids are incredibly common, Zota says, they’re poorly understood.
Scientists don’t know what causes these growths, although genetic mutations, sex hormone imbalance, and risk factors like age, race, obesity, and synthetic chemicals have been linked to them. But a recent study found that exposing fibroid cells to a metabolic byproduct DEHP stimulated the growth of these cells in the laboratory and delayed their death.“We’re not saying that phthalates start the tumors,” says gynecologist Serdar Bulun at the Northwestern University Feinberg School of Medicine, who led the research. “However, phthalates help these tumors grow to large sizes.” His team identified a molecular pathway that fosters the survival and growth of these tumor cells, providing strong mechanistic evidence connecting phthalate exposure with fibroids.
This research reinforces the link between these ubiquitous chemicals and a disease that’s greatly underappreciated, says Tracey Woodruff, a University of California, San Francisco, scientist studying the impact of environmental contaminants on reproductive health who wasn’t involved in Bulun’s research.
But phthalates are poorly regulated, Zota says, and almost impossible to avoid.
How phthalates enter our body
Called “everywhere chemicals,” phthalates are a family of chemical compounds that are manmade and often used as plasticizers to lend softness, flexibility, and durability to materials like polyvinyl chloride or PVC—one of the most widely used plastics—and synthetic rubber.
邻苯二甲酸盐被称为“无处不在的化学物质”，是一种人造化合物，经常被用作增塑剂，为聚氯乙烯或pvc(应用最广泛的塑料之一)和合成橡胶等材料提供柔软性、柔韧性和耐久性。
They are present in many household items ranging from food packaging and processing equipment to shower curtains, building materials, and car interiors.
它们存在于许多家庭用品中，从食品包装和加工设备到浴帘、建筑材料和汽车内饰。
Phthalates are also used as solvents in cosmetics and other personal care products and to coat or encapsulate certain pharmaceutical pills and dietary supplements.
邻苯二甲酸盐也被用作化妆品和其他个人护理产品的溶剂，并用于包裹或封装某些药物药丸和膳食补充剂。
The chemicals can leach out of these products and enter food, air, and water, meaning people can swallow, inhale, or absorb these phthalate particles through direct skin contact. The body then metabolizes these chemicals, yielding byproducts that several studies have detected in human urine, breastmilk, and blood.
While the U.S. Environmental Protection Agency often uses animal studies to determine safe exposure levels for humans, research suggests that certain phthalates can cause adverse effects on human health even at levels below the defined thresholds. For example, exposure to low levels of phthalates like DEHP, DBP, BBP, and DIBP during pregnancy were associated with neurological issues, including delayed cognitive development and memory impairment in children. These chemicals have also been linked with genital abnormalities in baby boys.
How phthalates impact uterine fibroids
In laboratory experiments, scientists have found that DEHP exposure allowed uterine fibroid cells in petri dishes to live longer and multiply more.
It’s also known that many fibroid cells harbor mutations in a gene called MED12, which may trigger tumor formation. The mutation may happen in a single stem cell, Bulun says, and then the cells just keep dividing and form the entire tumor. DEHP can enhance this process.
In a November 2022 study, Bulun and his colleagues demonstrated the molecular mechanism behind how a major DEHP byproduct called mono-(2-ethyl-5-hydroxyhexyl) phthalate affects tumor cells. Scientists often study such phthalate byproducts because the body rapidly breaks down the parent compound an individual may have been exposed to, yielding a family of metabolites that are excreted in the urine. The team found that the chemical helps tumor cells absorb an amino acid called tryptophan that gets converted to a compound called kynurenine which activates a protein receptor called AHR (aryl hydrocarbon receptor) that is known to initiate cancer. This active receptor promotes the growth of fibroid cells leading to larger growths.
“We’re thinking that if we can target and stop the conversion of tryptophan to kynurenine, then we can stop or block AHR activation,” Bulun says, “which could stabilize the tumors or shrink them.”
Living with uterine fibroids
While living with symptomatic uterine fibroids can be physically painful, the emotional toll of undergoing a hysterectomy for women who still aspire to get pregnant is heart-wrenching, says 46-year-old Saudia Davis, based in Chicago.
In August 2021, her fibroids had grown rapidly. Her tummy bulged. “I went from appearing to be four months pregnant to seven months,” Davis says. But the tumors were causing tremendous pain in her left butt cheek and with every sneeze or cough, she would feel a bit of incontinence. Davis underwent a hysterectomy 子宫切除 that year.
“I had to reconcile with the fact that I can’t bear my own child 我不得不接受我不能生育自己孩子的事实,” she says. “My fibroids were so large and encased in the uterus, they had to go.”
Neither Davis nor her doctors know why she developed these tumors in the first place or what triggered their sudden growth. Research shows that compared to white women, Black women like Davis are two to three times more likely to have uterine fibroids and their tumors tend to be larger and more numerous, leading to severe symptoms and higher rates of hysterectomy. Why they face heightened risks remains unclear.
She wonders if it was the hair relaxers she used from a young age until she was 42 years old to straighten her curly hair. These products can contain phthalates and their use could potentially be linked to uterine fibroids.
But it’s not easy to establish causation 但要建立因果关系并不容易, says environmental health scientist Kyungho Choi at South Korea’s Seoul National University. The time it takes for phthalates to break down in our body is hours, he says, and the levels can fluctuate over a couple of orders of magnitude every day. Knowing the exposure levels when the disease initiates is also important, Choi adds, but almost impossible to determine in the real world.
While we cannot change our age, our sex, or genetics, “we can still reduce the amount of chemicals we use,” he says. “Their contribution may be small, but we still have a handle on it.”
What Are Phthalates?
Phthalates are a group of chemicals which are used in the manufacture of plastic products.
邻苯二甲酸盐是一组用于制造塑料产品的化学物质。
These chemicals help soften plastics and allow them to be light, flexible and strong.
Think PVC, rubber ducks in the bathroom and wellie boots.
When used in cosmetics, phthalates help boost the absorption of this product into the skin, improve its texture and allow the product to be spread more evenly over the skin.
There are many types of phthalates which include:
DBP (di-n-butyl phthalate); DEP (diethyl phthalate); DEHP (di-(2-ethylhexyl) phthalate or bis (2-ethylhexyl) phthalate); BzBP (benzylbutyl phthalate); DMP (dimethyl phthalate)
You’ll find these chemicals absolutely everywhere, from cosmetics to perfumes, building materials, food storage containers, kids toys, electronics, household goods, food and drink, rain gear, and even baby toiletries.
What’s the Problem with Phthalates?
Numerous studies suggest that phthalates pose significant health risks for the human body.
Known as ‘endocrine disruptors 内分泌干扰物’ to the scientific community, these so-called ‘gender-bending’ chemicals could affect your natural hormone balance at all stages of life and trigger hormone imbalances like PCOS and PMT, trigger or worsen infertility, reduce sperm count and potentially increase your risk of developing breast cancer.
Phthalates appear to be especially harmful when it comes to the growth and development of unborn babies, contributing to genital deformation, premature puberty, lowered IQ, behavioural problems like ADHD, diabetes, reduced masculinisation and autism.
How to Avoid Phthalates
It’s certainly not an easy task to avoid phthalates as they are almost everywhere. However, you can take steps to reduce your exposure to this harmful chemical by taking the following steps.
1. Check your labels
Whilst you won’t find anything on a label that says ‘phthalates’ outright, you can identify those products most likely to contain them by checking which type of plastic the item is made from. Look for a recycling symbol and look out for the numbers 3 and 7. These are most likely to contain phthalates.
2. Avoid fragranced products
If you see the word ‘parfum’ or ‘fragrance’ on your product, you can almost guarantee that there are phthalates lurking in there somewhere. Opt for unscented or naturally scented products instead.
3. Never heat your food in plastic
When plastic is heated, it can leach chemicals into your food which then end up in your bloodstream. Instead choose glass, stainless steel or silicone bakeware instead.
4. Go organic!
The phthalates found in foods are the result of farmers spraying with pesticides. You can easily avoid these by choosing organic produce, organic meats and organic dairy instead.
5. Get a water filter
Unfortunately, phthalates are often used to line water pipes but you can avoid these by investing in a granular activated carbon filter to remove it.
6. Don’t use old plastic toys or food storage containers
Those cute toys from your childhood and vintage Tupperware containers were manufactured in a time before there were laws about phthalates or BPA, so they’re generally best avoided. But don’t worry – this only applies to soft plastics so your old Lego is safe.
7. Avoid plastics wherever possible
Phthalates and other harmful chemicals could be lurking in most plastic items in your home, so it’s best to avoid plastics wherever possible. Stainless steel, glass, silicone, cloth, paper and cardboard are great eco-friendly alternatives.
How to Spot Phthalates on Ingredients Lists
Unfortunately, ingredients lists generally make it difficult to identify phthalates. They are usually written as a 3 or 4-word acronym. Here are some to look out for:
BBP (butyl benzyl phthalate); DBP (di-n-butyl phthalate); DEHP (di-(2-ethylhexyl) phthalate); DEP (diethyl phthalate); DiDP (di-isodecyl phthalate); DiNP (di-isononyll phthalate); DnHP (di-n-hexyl phthalate); DnOP (di-n-octyl phthalate)
How to Know if Phthalates are in the Cosmetics You Use
Historically, the primary phthalates used in cosmetic products have been dibutylphthalate (DBP), used as a plasticizer in products such as nail polishes指甲油 (to reduce cracking by making them less brittle); dimethylphthalate (DMP), used in hair sprays发胶 (to help avoid stiffness by allowing them to form a flexible film on the hair); and diethylphthalate (DEP), used as a solvent and fixative in fragrances香水. According to the FDA's latest survey of cosmetics, conducted in 2010, however, DBP and DMP are used rarely. DEP appears to be the only phthalate still commonly used in cosmetics.
Under the authority of the Fair Packaging and Labeling Act (FPLA), the FDA requires an ingredient declaration on cosmetic products sold at the retail level to consumers. FDA要求在零售销售给消费者的化妆品上进行成分声明 Consumers can tell whether some products contain phthalates by reading the ingredient declaration on the labels of such products.
However, the regulations do not require the listing of the individual fragrance or flavor, or their specific ingredients. Fragrance or flavor may be listed as such. As a result, a consumer may not be able to determine from the ingredient declaration on the label if phthalates are present in a fragrance or a flavor used in the product. Based on currently available safety information, the FDA does not have safety concerns with the use of DEP as currently used in cosmetics and fragrances. Consumers who nevertheless do not want to purchase cosmetics containing DEP may wish to choose products that do not include "Fragrance" or “Flavor” in the ingredient declaration.
Possible Health Effects of Phthalates in Cosmetics
The FDA considers all available scientific literature on the safety of phthalates in cosmetics published by the scientific community.
In 2002, the Cosmetic Ingredient Review (CIR) Expert Panel, an industry-sponsored organization that reviews cosmetic ingredient safety and publishes its results in open, peer-reviewed literature, reaffirmed its original conclusion (reached in 1985), finding that DBP, DMP, and DEP were safe as used in cosmetic products. (See “Annual Review of Cosmetic Ingredient Safety Assessments 2002/2003,”International Journal of Toxicology (Supplement 1), 1-102, 2005.) Looking at maximum known concentrations of these ingredients in cosmetics, the panel evaluated phthalate exposure and toxicity data, and conducted a safety assessment for DBP in cosmetic products. The panel found that levels of exposures to phthalates from cosmetics were low compared to levels that may cause adverse effects in animals.
The Centers for Disease Control and Prevention (CDC) released a report on March 21, 2001, titled"National Report on Human Exposure to Environmental Chemicals."The report described a survey of a small segment of the U.S. population for environmental chemicals in urine to learn more about the extent of human exposure to industrial chemicals. One group of chemicals surveyed was phthalates. While the CDC report noted elevated levels of phthalates excreted by women of child-bearing age, neither this report nor the other data reviewed by the FDA established an association between the use of phthalates in cosmetic products and a health risk. Based on this information, the FDA determined that there wasn’t a sound, scientific basis to support taking regulatory action against cosmetics containing phthalates.
An expert panel convened by the National Toxicology Program, part of the National Institute of Environmental Health Sciences, from 1998 to 2000, concluded that reproductive risks from exposure to phthalates were minimal.
As the FDA continues to follow the ongoing scientific discussions, we will consider additional actions as needed.
The FDA's Role in Regulating Phthalates in Cosmetics
Under the law, cosmetic products and ingredients, with the exception of color additives, are not subject to FDA approval before they go on the market. Cosmetics must be safe under the labeled or customary conditions of use, and the FDA can take action against cosmetics on the market that do not comply with the law.
At the present time, the FDA does not have evidence that phthalates as used in cosmetics pose a safety risk. If we determine that a health hazard exists, we will advise the industry and the public, and will take action to protect consumers within the scope of our authority under the Federal Food, Drug, and Cosmetic Act. For related information, seeFDA Authority Over Cosmetics.
The FDA’s Continued Evaluation of Phthalates in Cosmetics
The FDA continues to monitor levels of phthalates in cosmetic products. We have developed an analytical method for determining the levels of phthalates in a survey of marketed cosmetic products.
The FDA published this analytical method and results of our 2004 survey in the article, “Analysis of Consumer Cosmetic Products for Phthalate Esters,” (J.C. Hubinger and D.C. Havery,Journal of Cosmetic Science, 2006, vol. 57, pp. 127-137). We conducted a second survey in 2006. Results were published in the article,“A Survey of Phthalate Esters in Consumer Cosmetic Products," (PDF 488 KB) (J.C. Hubinger, Journal of Cosmetic Science, 2010, vol. 61, no. 6, pp. 457-465). Results of a third survey, concluded in 2010, are shown below in the table, 2010 Survey of Cosmetics for Phthalate Content. We learned from these surveys that use of phthalates in cosmetics decreased considerably from 2004 to 2010.
Infant Exposure to Phthalates in Personal Care Products
Infants, like all consumers, are exposed daily to phthalates from a number of sources, including air, drugs, food (including breast milk), plastics, water, and cosmetics. The American Academy of Pediatrics published an article stating that infants exposed to infant care products, specifically baby shampoos, baby lotions, and baby powder, showed increased levels of phthalate metabolites in their urine (see“Baby Care Products: Possible Sources of Infant Phthalate Exposure,” S. Sathyanarayana,Pediatrics, 2008, vol. 121, pp. 260-268). This biomonitoring study was not designed to establish an association between these findings and any adverse health effects. In addition, levels of phthalates, if any, in the infant care products were not determined in this study.
In its survey that was completed in 2006, the FDA included 24 children’s products intended for infants and children, and included nearly 50 products for infants and children in the survey we completed in 2010. We learned that the use of phthalates in cosmetics intended for people of all ages, including infants and children, has decreased considerably since our surveys began in 2004.
Results of the FDA's 2010 Survey of Cosmetics for Phthalate Content
The products listed below represent a sample of cosmetics on the market at the time the survey was conducted, and products may have been reformulated since then. This survey was intended to monitor trends in the use of phthalates in cosmetics, not as a comprehensive analysis of all cosmetics on the market. The law does not require cosmetic firms to file their formulations with the FDA. Also, please note that some so-called "personal care products," such as diaper creams and nipple creams, are regulated as drugs, or in some cases both cosmetics and drugs.
