They seem like pretty harmless acts: letting your daughter apply a layer of lip gloss or mouth the metallic charm on some children’s jewelry. But those simple actions may be exposing her to harmful metals, such as arsenic, cadmium, chromium, and lead.
Two recent studies are bringing the problem of these potentially harmful elements—which have been reported before—as well as other toxic metals in such products back in the spotlight. Both studies are of particular concern because they involve products frequently used by or intended specifically for children, for whom exposure to these metals is more dangerous because their bodies and brains are still developing.
In one study, researchers at the University of California, Berkeley, took 32 lipsticks and lip glosses used by a group of 14- to 19-year-old girls and women and tested them for nine toxic metals using inductively coupled plasma optical emission spectrometry (Environ. Health Perspect. 2013, DOI: 10.1289/ehp.1205518). They then estimated how much of these metals people were consuming on the basis of how often they applied the lip products and compared those figures to acceptable daily intakes, based largely upon California drinking water standards.
The researchers estimated that women get more than 20% of their acceptable daily intake of aluminum, cadmium, and chromium from applying lipstick roughly twice per day. “Since there are other sources of these metals, you want to keep any one source under 20%,” explains S. Katharine Hammond, who led the study, along with colleagues Sa Liu and Ann Rojas-Cheatham.
Women who apply lip products more frequently, approximately nine times per day, are exposed to even higher levels of those metals, exceeding their total acceptable daily intakes by 3% for aluminum and 68% for chromium.
Cadmium is of particular concern because it is a known human carcinogen and chronic oral exposure can lead to kidney and bone impairments. Exposure to hexavalent chromium, Cr(VI), via drinking water has been linked to stomach tumors. It’s important to note that the spectrometry technique the Berkeley group used to identify the metals was unable to differentiate between their oxidation states, so the researchers don’t know whether the lip products contained carcinogenic Cr(IV) or, for example, Cr(III), which is sold as a dietary supplement.
Hammond’s group also found lead in 75% of the lip products they tested. This did not come as a surprise as several previous studies, including one of 400 lipstick samples conducted by the Food & Drug Administration, had identified the element in trace amounts in lipsticks.
“We found that the levels of lead, although they were present in most of the products, were at low levels,” Hammond says. “They didn’t rise to the level of concern that some of the other metals rose to.” Even so, she notes that lead exposure is still of concern when children are using the products. The Centers for Disease Control & Prevention points out that “even low levels of lead in blood have been shown to affect IQ, ability to pay attention, and academic achievement.”
“If you use lipstick moderately, I wouldn’t worry too much about it,” Hammond tells C&EN. “I would worry if you have children who are using it or if you use it a lot.”
Worry is not warranted, contends Linda Loretz, the chief toxicologist for the Personal Care Products Council, a trade association for the cosmetics industry. “The finding of trace levels of metals in lip products is not unexpected given their natural presence in air, soil, and water,” she said in a statement.
But Hammond disagrees. “I’ve gotten a lot of questions about what products are safe,” she says. “I think it’s FDA’s job to determine that.”
Tamara Ward, a spokeswoman for FDA, says the agency will conduct a thorough review of the Berkeley report. “We are also currently taking steps to evaluate cosmetics for possible trace levels of heavy metals,” she says.
In a second study, Gérald J. Zagury and Mert Guney of Montreal Polytechnic used acid digestion followed by inductively coupled plasma optical emission spectrometry to test 72 toys and children’s jewelry items purchased in North America for 10 harmful elements (Environ. Sci. Technol. 2013, DOI: 10.1021/es304969n). They found that especially in metallic toys and children’s jewelry, contamination by lead and cadmium and to a lesser extent by copper, nickel, arsenic, and antimony poses an acute problem.
Zagury tells C&EN that his goal was not simply to determine the amount of dangerous metals in these products but also to determine whether the products are capable of getting into a child’s system if mouthed or ingested. “We found that a lot of things were published on total metal content of toys or children’s jewelry, but not much on what happens when they are ingested or what happens when they interact with saliva in the mouth,” he says.
To remedy that, he and Guney developed a test that simulates mouthing—by scratching the products and then exposing them to simulated saliva—as well as conditions inside the stomach and intestines. In the study, they exposed four selected items to gastrointestinal conditions and found that one item of children’s jewelry leached about 700 μg of lead in simulated ingestion scenarios. The Consumer Product Safety Commission recommends that children not ingest more than 175 μg of accessible lead in a short period of time.
Since submitting the paper for publication, Zagury says they’ve done such bioaccessibility testing on roughly 30 samples of toys and children’s jewelry. Pliable plastic and painted or coated toys were far less problematic than metallic toys and jewelry, Zagury says. Many of the latter, he says, are made from recycled metal that contains lead or cadmium as part of its matrix.
Zagury says his group’s study cannot conclude that the metal contamination stems from the toys having been manufactured in countries with weak safety standards, such as China.“We found that even famous toy brands were not safer than other brands,” he says. “Even if a toy is expensive, it’s not a guarantee that it’s free of these contaminants.”
Commenting on the two papers, Ellen Silbergeld, an expert in environmental health at Johns Hopkins Bloomberg School of Public Health, says, “Given the propensity of children to put things in their mouths and play with lipsticks and toys, I think this is a very serious issue.” She is particularly concerned about the presence of lead in lip products, toys, and children’s jewelry. “We do not know of a level of lead that is without risk, and therefore we take pretty seriously any preventable exposure,” she says.
However, “there are some significant limitations to these recent studies,” Silbergeld adds. “First, as noted by the authors, there are no data on specific forms of metals, which can influence their toxicity.” Second, Silbergeld disagrees with the researchers’ methods of estimating exposure from mouthing.
Nevertheless, “the levels of lead, cadmium, and other heavy metals may raise some concern about cumulative exposure to a mixture of chemicals,” adds Aimin Chen, who specializes in environmental and pediatric epidemiology at the University of Cincinnati College of Medicine. “Regulatory agencies should notice the metal content and take action to protect children from unwanted contamination.”