Phthalates and Children’s Products

Environmental Exposures, Other Cancers, Prevention
Paul Brown, Keris Krenn Hrubec, Dana Casciotti, PhD, Brandel France de Bravo, MPH, Stephanie Fox-Rawlings, PhD, Cancer Prevention & Treatment Fund

Phthalates are synthetic chemicals found in every home, in plastic toys, personal care products such as shampoos and lotions, vinyl floors, and shower curtains. They are also found in some medical products, such as saline bags, feeding tubes and catheters. They are used to make plastic flexible and to add fragrances to soap and other personal products.  Unfortunately, these chemicals don’t stay inside the products. Based on recent research on ants, scientists have concluded that the high levels of phthalates in the bodies of insects around the world are the result of phthalates in the air.[1] Because phthalates are released into the air and dust around us, they are found in human urine, blood, and breast milk.[2] Levels are highest in women and children ages 6 to 11. Young children may have higher levels of phthalates in their bodies because their hands find their way into their mouths more frequently: they touch objects made with phthalates and surfaces covered with phthalate dust, and then their hands touch their mouths.

Phthalates are called “endocrine disruptors” because they affect the body’s hormones by mimicking them or blocking them. They interfere with the body’s natural levels of estrogen, testosterone, and other hormones, which is why they are called “disruptors.” Endocrine disruptors are hard to study for several reasons: 1) we are exposed to very small quantities from many different sources every day, 2) researchers have proved that, unlike other chemicals, these appear to have more serious effects at lower levels than at higher levels.[3] Usually, we assume that the higher the dose or exposure, the greater the harm, but endocrine disruptors play by different rules. The director of the National Institute of Environmental Health Sciences, Linda Birnbaum, says that chemical manufacturers are asking “old questions” when they test for safety even though “science has moved on.”[4]

Hormones can increase the risk of some cancers, whether those hormones are natural or synthetic. Too much or too little of a hormone can be harmful. Is a child who is exposed to phthalates more likely to develop cancer as an adult?  No one knows for sure but animals exposed to phthalates are more likely to develop liver cancer, kidney cancer, and male reproductive organ damage.[5]

Phthalates are believed to also affect girls’ hormones, but the health impact is not yet known. Studies also show associations between children’s exposure to phthalates and the risk of asthma, allergies and bronchial obstruction.[6][7][8]

Researchers at Mount Sinai also found a link between obesity and phthalates.[9] They found that among overweight girls ages 6 to 8, the higher the concentration of certain phthalates (including low molecular weight phthalates) in their urine, the higher their body mass index (BMI).  BMI takes height and weight into account when determining if someone is overweight. A study among Danish children ages 4 to 9 found that the higher the concentration of phthalates (all of them), the shorter the child. This was true for girls and boys.[10] More research is needed to determine the impact of phthalates on height and BMI.

Even short-term exposure has now been linked to developmental deficits.[11] Researchers found that children in intensive care units were exposed to the phthalate DEHP through plastic tubing and catheters. The children had 18 times (!)  as much DEHP in their blood compared to children who had not spent time in the ICU. Four years later, the children who had been exposed to DEHP had more problems with attention and motor coordination. The researchers found that the DEHP caused these problems regardless of medical complications or treatments.

Prenatal Exposure to Phthalates

Childhood exposure to phthalates begins in the womb. Several studies that have tested phthalate levels in women in their third trimester of pregnancy have found health effects in the infants, toddlers, and older children of the mothers with the highest levels. There are many different types of phthalates. Most studies look at several types, and the effects tend to vary by type.  A 2011 study found that six-month-old boys whose mothers had the highest phthalate levels scored lower on brain and motor development tests.[12] The same effect was not true for female infants.

Research indicates that boys exposed to phthalates while in the womb may be more likely to develop smaller genitals and incomplete descent of the testicles.[13] Boys who are born with undescended testicles are 2-8 times more likely to develop testicular cancer later on than men born with both testicles descended[14] (their risk is lessened if they get corrective surgery before age 13.[15]). Studies by Harvard researchers have shown phthalates may alter human sperm DNA and semen quality.[16][17][18][19]

Columbia University researchers discovered that three-year olds with high prenatal exposure to two types of phthalates were more likely to have motor delays.[20] They also reported that three phthalates were linked to certain behavior problems in three-year olds, such as social withdrawal.  One phthalate in the study was linked to lower mental development in girls.

Other studies have also linked increased prenatal phthalate exposure to behavior problems. Researchers in Taiwan found an association with aggressive and disobedient behaviors in eight-year-olds of both sexes.[21][22] Similarly, researchers from Icahn School of Medicine at Mount Sinai found that higher levels of exposure to phthalates during gestation were associated with aggression, rule-breaking, and conduct problems for males only.[23]

Researchers at Mount Sinai School of Medicine studied the impact of prenatal exposure to “low molecular weight” phthalates—the kind often found in personal care products and the coatings of some medications—on the social behavior of children ages 7 to 9. Children who were exposed to higher levels of these phthalates, which include DEP and DBP, had worse scores for social learning, communication, and awareness.  This means they were less able to interpret social cues, use language to communicate, and engage in social interactions.[24]

What Is Being Done to Limit Children’s Exposure?

As of February, 2009, children’s toys and child care products sold in the U.S (such as teething rings and plastic books) cannot contain certain phthalates.  The ban on those phthalates is the result of a law passed in 2008, the Consumer Product Safety Improvement Act.  The law permanently bans certain kinds of phthalates (BBP, DBP and DEHP) from toys and child care products, and temporarily bans other phthalates (DIDP, DINP and DnOP) until a scientific board (the Chronic Hazard Advisory Panel) determines for the Consumer Product Safety Commission (CPSC) whether or not they are safe. In 2014 the Chronic Hazard Advisory Panel determined that stricter regulations were appropriate.[25] It stated that the permeant bans should remain on BBP, DBP and DEHP, and that DINP should be added to this list. Furthermore, because a large component of exposure to these chemicals comes from food and other products, it recommended increased regulation. The panel was less concerned about DIDP and DnOP, but recommended additional study. Finally, the panel recommended permanently banning DIBP, DPENP, DHEXP, and DCHP, and putting an interim ban on DIOP.

A few months before the 2008 bill passed, major retailers such as Wal-Mart, Target, and Babies “R” Us promised to remove or severely restrict children’s products containing phthalates by the end of 2008.[26] That provided added incentives for major companies making teething rings and other soft plastic products to stop using phthalates.

The ban in the U.S.followed similar bans in other countries.  In 2006, the European Union banned the use of 6 phthalates in toys that may be placed in the mouth by children younger than 3 years old.[27] The banned phthalates are DINP, DEHP, DBP, DIDP, DNOP, and BBzP.  Fourteen other countries, including Japan, Argentina, and Mexico, had also banned phthalates from children’s toys prior to the U.S.

Phthalate Exposure Continues

A 2014 study looking at data over a ten-year period (2001– 2010) found that exposures to some phthalates have declined while others have increased. Americans’ exposure to three substances permanently banned in toys and children’s products—DEHP, DBP and BBP—has declined. But exposure to other phthalates such as DiNP and DiBP, as measured in urine, has increased. The higher  levels of DiBP and other phthalates “suggest that manufacturers may be using them as substitutes for other phthalates even though the US EPA has expressed concern about their use.”[28] It is surprising that DiNP exposure has gone up since it was banned on an interim basis from children’s toys and children’s products.  Additionally, in 2013, California declared DiNP a carcinogen.[29]

Even with the ban on phthalates in children’s toys, children, and adults, too, continue to be exposed because these chemicals are in many products, including food packaging, pharmaceuticals, medical devices and tubing, soap, lotions, and shampoos.[30] Johnson & Johnson recently reformulated its baby shampoo to remove harmful chemicals,[31] and Proctor & Gamble has promised to eliminate the phthalate DEP from fragrances used in its products by the end of 2014.[32] DEP is used in personal care products  and “reductions in DEP exposures have been the most pronounced,” according to the 2014 study.[33] Ten years ago, more than a thousand companies pledged to remove “chemicals of concern from personal care products,” however, it is unclear how many have done so. The U.S. Food and Drug Administration (FDA) regulates many of these products, including baby shampoo and baby lotion.  If the FDA does not decide to ban phthalates from these products, legislation would be required to do so.

The U.S. Environmental Protection Agency (EPA) developed an “action plan” in 2010 for eight phthalates “because of their toxicity and the evidence of pervasive human and environmental exposure.” [34] The phthalates are being studied for health effects and for alternatives. The EPA developed two new rules for these chemicals. However, the rules were delayed and then withdrawn in 2013.[35] In 2014, seven of these phthalates were included in the Toxic Substances Control Act work plan, because of their potential for harm and the frequency of exposure.[36] The eighth phthalate (DnPP) was not included because it is no longer being used in new products. The chemicals on the work plan are to be assessed for additional study or regulation, but it is unclear when that assessment will occur.

While other government agencies are concerned about phthalates in specific products, the EPA’s job is to focus on the chemicals for use in any kind of product and establish safety standards for each phthalate.  A challenge for the EPA is to set safety standards that make sense given that people may be exposed to several phthalates from many different sources. Teenage girls, for instance, have been found to use up to 17 personal care products a day.[37] Setting safety standards for phthalates individually or for individual products without considering their interactions and cumulative effects could underestimate the real-world risks of phthalates to the health of children and adults.

All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.

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