Before a sunscreen can carry a sun protection factor, or SPF, in the United States, a technician outlines small squares on the backs of volunteers in indelible ink and spreads the product over some of them with a finger cot, 2 milligrams to every square centimeter. A second lotion goes on beside it, made to a recipe printed in federal regulations: water, lanolin, cocoa butter, stearic acid, 7 percent padimate O, and 3 percent oxybenzone. A solar simulator, a lamp built to imitate sunlight, then gives each square a rising dose, and the next day the technician reads which squares have just turned red. If the reference lotion's SPF on that panel falls outside 16.3, give or take 3.43, the test of the product does not count. 1
In February 2019 the same agency, the Food and Drug Administration, or FDA, proposed that oxybenzone lacked the data to be called generally recognized as safe and effective, its standard for an ingredient sold without a prescription. It asked manufacturers for studies of how much reaches the blood, what it does to hormones and development, and whether it causes cancer. As of September 2026 the agency has not ruled, and the reference lotion in its current rule still contains 3 percent oxybenzone. 2; 3; 1
Oxybenzone, also called benzophenone-3, is a sunscreen chemical that absorbs UVB, the short band of ultraviolet that causes most sunburn, and part of UVA, the longer band. In the FDA's 2020 absorption trial, all 24 people who used a product containing it had it in their blood within two hours of a single application. A national survey found it in the urine of 96.8 percent of 2,517 Americans tested in 2003 and 2004, and people who use no sunscreen carry it too, because it is also in lotions, lip balms, cosmetics, and plastics. 4; 5; 6
Studies in breast cancer cells and in rats have found that oxybenzone acts as a weak estrogen at high doses, and studies in people that compared a urine sample with hormone levels have found links pointing in different directions. No study has shown that it causes disease in anyone. Among 23,908 North American patients patch tested for skin allergies from 2001 to 2010, 82 reacted to it, about 1 in 300. The European Union and Britain allow it at up to 2.2 percent in body sunscreens, and Hawaii has banned its sale without a prescription since 2021. 7; 8; 9; 2; 10; 11; 12
This page covers where oxybenzone came from, what the first animal studies found, who reacts to it in light, how it enters the body and from which products, what it does in cells, animals, and people, including in pregnancy, what the cancer and coral studies measured, and how regulators have ruled. The absorption trials, urine surveys, and reef laws for all sunscreen chemicals are on the sunscreen page. Each study is named as real sun, a lamp or solar simulator, a product applied to people, animal feeding, cells, or a measurement in blood, urine, milk, or tissue.
Key facts
- In 1978 an FDA advisory panel recorded that 96.51 percent of the oxybenzone in a lotion was recovered from the forearms of 14 people after four hours; in the FDA's 2020 trial all 24 users had it in their blood within two hours of one application. 13; 4
- Rats fed oxybenzone at 50,000 parts per million of their diet for 13 weeks had markedly lower sperm density, and a two-year feeding study found "equivocal evidence" of cancer in rats and "no evidence" in mice. 14; 15
- In a Toulouse clinic from 1990 to 1994, 27 of the 57 sunscreen allergies found among 370 patients with suspected light-triggered rashes were to oxybenzone. 16
- Boys aged 12 to 19 in the top quarter of urine oxybenzone had 37 percent less testosterone than boys in the bottom quarter, while girls in the top fifth began breast development 5 to 6 months later than girls in the bottom fifth. 8; 9
- The EU's safety committee calculated a margin of safety of 38 for a whole-body sunscreen with 6 percent oxybenzone, and the EU cut the limit for body products to 2.2 percent in 2022. 17; 10
Oxybenzone was patented as a plastics stabilizer in the 1950s and judged safe for sunscreen in 1978
Oxybenzone's chemical name is 2-hydroxy-4-methoxybenzophenone, and it belongs to the benzophenones, a family of chemicals that absorb ultraviolet light. A 1958 patent credits a 1906 German paper with describing how to make it. 18; 19 In the 1950s two American chemical companies patented ways to make benzophenones like it for plastics. American Cyanamid's 1956 patent called them "very useful as ultraviolet absorbers" in polyester resins, and the 1958 patent, from General Aniline and Film, wanted the pure compound for "colorless organic film-forming plastics, resins, gums, waxes". 20; 19 By 1957 a dermatology journal was describing benzophenones as "ultraviolet light absorbing agents". 21
In a test published in 1970, Stephen Katz marked out squares of previously unexposed skin on the buttocks or shaved lower bellies of nine men. He spread four sunscreens on one side, among them a cream with 3 percent oxybenzone and 3 percent dioxybenzone, had the men swim for ten minutes in a freshwater pool, then dried them and put the same products on the other side. Every square took an hour of "the maximum possible natural sunlight", and three observers graded the redness the next day from 0, "no reaction", to 4, "bright and fiery red". Applied after the swim, the oxybenzone cream kept the skin between 0 and 2, "pink", and applied before it, no product protected consistently. 13; 22
The FDA's advisory panel on sunscreens, a committee of outside experts, published its review in August 1978 and put oxybenzone in its first category, safe and effective, at 2 to 6 percent. Its safety section opens with a sentence the panel used, with the name changed, for ingredient after ingredient: "Clinical use and marketing experience have confirmed that oxybenzone is safe in the dosage range used." The evidence under it included rats that survived more than 12.8 grams per kilogram by mouth, rabbits whose eyes "remained completely free of irritation", and one absorption test. Fourteen people had about half a gram of a lotion with 6 percent oxybenzone and 12 percent homosalate spread on a 1 by 3 inch patch of forearm, and after four hours 96.51 percent of the oxybenzone was recovered from the skin. The panel called that "essentially complete recovery of the test material". 13
Under a solar simulator, a lotion with 3 percent oxybenzone raised the dose of light needed to redden skin by a factor of 2.37, against 1.31 for the plain lotion and 7.06 for 4 percent padimate O, a relative of para-aminobenzoic acid, or PABA, the older sunburn chemical. The panel noted that oxybenzone was "frequently used in combination with other sunscreens". 13 In 1979 the cosmetics industry's trade association counted 62 cosmetic products that contained it, and the largest group was nail polish and enamel. 14 It is also approved as an additive in acrylic plastics that touch food. 15 Through the early 1990s it replaced PABA in sunscreens, the FDA wrote in 2019, "because of its superior UVA coverage". 2
Rats and mice given oxybenzone for 13 weeks had fewer sperm; an industry-sponsored repeat on mouse skin found no fall
The National Cancer Institute nominated oxybenzone for testing in 1979, because so many people were exposed to it and it had never been tested for cancer, and a private individual nominated it as well, to find out whether it damaged genes. 2; 15 From 1985 to 1988 a contract laboratory in Worcester, Massachusetts, ran the National Toxicology Program's first studies of it. Rats and mice ate feed containing up to 50,000 parts per million of oxybenzone, 5 percent of their food, for two or thirteen weeks, and other groups had it painted on their skin. 14
Rats on the richest diet had "markedly lower" sperm density, longer estrous cycles, which are the reproductive cycles of female rodents, and damaged kidneys. On the skin, rats given up to 200 milligrams per kilogram for 13 weeks showed heavier kidneys in the females and nothing else that the report attributed to oxybenzone. Mice given it on the skin for 13 weeks had lower sperm density at all three doses measured, 22.75, 91, and 200 milligrams per kilogram. 14
When outside scientists reviewed the report, one principal reviewer, Dr. Goodman, asked why the study had been done at all, since an FDA panel and a cosmetic ingredient review panel had both judged oxybenzone safe. He asked how the doses that caused harm compared with what a person would get from sunscreen, and the program's Dr. French answered that "this would be difficult to do". Richard Davis of American Cyanamid, the company whose 1956 patent had described such benzophenones as ultraviolet absorbers, suggested also counting spermatids, sperm cells still forming in the testes, and noted a threefold spread in sperm density among the unexposed groups alone. A note added before publication recorded that later studies on mouse skin, "sponsored by the Cosmetic Toiletry and Fragrance Association", found no significant fall in sperm density. 14
In 2019 the FDA cited the 13-week results and noted that they came from feeding and from skin doses in acetone, "methods of exposure" that "could potentially lead to higher levels of systemic exposure to oxybenzone than with sunscreen use", and said that data on absorption were needed to judge whether the findings applied to sunscreen. 2
In clinic series oxybenzone is among the commonest causes of sunscreen photoallergy
In 1987 a 61-year-old man was referred to Columbia-Presbyterian Medical Center in New York for a rash on his face and the backs of his hands. He wore sunscreen whenever he expected to be outdoors, and his own doctor had diagnosed an unexplained sensitivity to light and treated it with PUVA, a drug called methoxsalen followed by doses of UVA. "After six treatments with oral methoxsalen plus UV-A light, the rash worsened." 23
Photopatch tests, in which suspect chemicals are taped to the back in two sets and one set is given UVA from a lamp, found that he and three other patients had a photoallergy to oxybenzone, a reaction that appears only where light falls on skin carrying the chemical. The Columbia authors expected such reactions to "become more commonplace" because oxybenzone was "by far the most frequently used agent" in sunscreens above SPF 8. 23
In June 1989 a 28-year-old woman in London with a mild light rash on her neck put a sunscreen called Caribe Factor 20 Babyscreen on her face and chest and spent several hours in the sun "wearing a bikini top and shorts". An eczema followed where the sunscreen had been, and afterward "5 min of sunshine exposure regularly precipitated" her rash at every exposed site. 24
In Toulouse from 1990 to 1994, 370 patients with suspected light-triggered rashes had patch and photopatch tests, 57 were allergic to a sunscreen, and 27 of those reactions were to oxybenzone. 16 In Bogotá from 2011 to 2013, oxybenzone caused 11 of 20 photopatch reactions among 100 patients, and several patients who reacted to sunscreen chemicals "insisted that they had not used sunscreens". 25 A 2010 study in Portland, Oregon, started from the other end, with 27 people who said they were allergic to sunscreen; 11 agreed to four days of testing, 8 of them had no reaction, and one reacted to oxybenzone. The authors titled their paper "True Photoallergy to Sunscreens Is Rare Despite Popular Belief". 26
A 40-year-old childcare assistant in Liverpool came out in a "nettle rash" soon after putting sunscreen on her daughter in May 2000. A month later a fake-tan product brought on "stomach cramps, an extensive rash, swelling of lips and tongue and eventually syncope", a faint. Patch tests traced both to oxybenzone, which was in three of the four cosmetics she brought in. 27
A 45-year-old man in Minneapolis who built hydraulic pumps washed his hands and face "up to 30 times a day", used lip balm "numerous times per day", ate hard candies or chewing gum "all the time" at work, and drank "gallons" of flavored drinks. Patch tests gave strong reactions to benzophenone-3 and to his Blistex, which contained it, and once he avoided both he was free of dermatitis at a three-month visit. 28
In 2019 the FDA wrote that the evidence "establishing oxybenzone as a photoallergen in individuals with photosensitivity is clear" and asked for no more studies of it. Its adverse event files held 31 reports of hypersensitivity to oxybenzone sunscreens from 1988 to 2011, 4 of them anaphylaxis. 2
In sunlight oxybenzone reacts on the skin; under a lamp, one skin model made more free radicals after an hour
At midday in May, at latitude 54 degrees in England, Karin Schallreuter's group spread Soltan Facial Cream, an SPF 25 product with oxybenzone, on a metal plate and on the inner arms of eight people and set them in the sun for 15 minutes. They followed the chemical with Raman spectroscopy, which reads molecules with a laser without cutting the skin. The oxybenzone oxidized quickly into a reactive form, and the spectra showed a band the authors read as oxybenzone bound to glutathione, one of the skin's own antioxidants. In one volunteer "with skin type 1 and red hair" the first change appeared only briefly and was followed by a rapid rise in the signal for sulfur bonds. The authors wrote in 1996 that oxybenzone "may be rather harmful to the homeostasis of the epidermis". 29
In 2006 a group at the University of California, Riverside, spread an oxybenzone formula on laboratory-grown human skin at the test thickness and gave it a dose of ultraviolet from a lamp. They imaged reactive oxygen species, unstable oxygen molecules that can damage DNA and proteins, in the living layers of the skin. Straight after application the sunscreen chemical cut them sharply. After 20 minutes it cut them less, and by 60 minutes skin with oxybenzone made more of them than skin without it, which the authors traced to oxybenzone that had soaked into the layers of living cells. Octocrylene and octinoxate did the same. 30
Oxybenzone acts as a weak estrogen in breast cancer cells and in rats fed more than 1,000 milligrams per kilogram a day
Margret Schlumpf's group at the University of Zurich started from a finding in fish: in 1991 and 1993 six sunscreen chemicals had been found in the perch and roach of the Meerfelder Maar, a crater lake in Germany's Eifel hills. Paid by the Swiss environment agency, they reported tests of six sunscreen chemicals for estrogen activity in 2001, estrogen being the hormone behind female development and the growth of some breast cancers. In MCF-7 cells, human breast cancer cells that multiply faster under estrogen, oxybenzone pushed growth as far as estradiol, the body's main estrogen, but needed 3.73 micromolar to reach half that effect, against 1.22 picomolar for estradiol, a concentration about three million times lower. Immature rats fed oxybenzone in powdered food for four days grew heavier wombs only at 1,525 milligrams per kilogram a day, and the authors called the effect weak. They concluded that "UV screens should be tested for endocrine activity". 7
The sunscreen page gives a 2011 calculation that a woman would need 34.6 years of daily whole-body sunscreen to take in the oxybenzone these rats ate. It began from the Zurich study's 1,525 milligrams a day for four days. 31 In 2019 the FDA noted reports that "some oxybenzone metabolites are more hormonally active than the parent drug". 2 A metabolite is a chemical the body makes from another, and oxybenzone's main one in urine is benzophenone-1. 32
In 2018 a University of Massachusetts group fed pregnant mice oxybenzone from the first day of pregnancy until their pups were weaned, at 30, 212, or 3,000 micrograms per kilogram a day. The authors chose the doses to match a tolerable daily intake, the exposure of pregnant women at the top 5 percent of urine levels, and the highest dose that had caused no harm in earlier animal tests. Five weeks after the mothers stopped nursing, those given the top dose had permanently denser ducts in their mammary glands than both the unexposed mothers and mice that had never been pregnant. 33
In 2023 five employees of Procter and Gamble compared the concentrations at which six sunscreen chemicals act in ToxCast, a federal program that screens chemicals in automated laboratory tests, with the peak blood levels in the FDA trials. For five of them the gap was more than a hundredfold. For oxybenzone, the peak in blood at maximal use, 1.13 micromolar, came within tenfold of the 4.92 micromolar that set off an estrogen-response test. The authors wrote that there has been "no definitive cause-effect evidence" that such chemicals disrupt hormones in people. 34
Oxybenzone passes through skin into the blood and leaves in urine over several days
In Göteborg in 2002, 11 volunteers spread about 40 grams of a commercial SPF 14 lotion with 4 percent oxybenzone over the whole body, got dressed, and collected their urine for 48 hours, with no sun. On average 11 milligrams of oxybenzone came out, about 0.4 percent of what went on, and four of the eleven were still passing it two days later. The authors wrote that for small children zinc oxide or titanium dioxide "remain a better choice". 35
A Winnipeg study in 2004 spread a children's sunscreen, Coppertone Colorblok for kids, SPF 30, with 6 percent oxybenzone, on the arms and backs of three women. Up to about 1 percent of the oxybenzone and its metabolites came out in urine, and small amounts appeared in the blood. Hill Top Research, a Winnipeg research company that employed one of the authors, helped pay for it. 32
Inside the body most oxybenzone is bound to glucuronic acid, a sugar acid the body attaches to many chemicals so that the kidneys can clear them; in urine from 30 adult volunteers, only 3 percent came out free. 36 The 2020 FDA trial, described on the sunscreen page, measured how fast oxybenzone arrives and how long it stays. All 24 people using an oxybenzone product passed the agency's threshold of 0.5 nanograms per milliliter within two hours of a single application, while the other five sunscreen chemicals took 3 to 23 hours to reach it in three quarters of their users. Oxybenzone peaked at 258.1 nanograms per milliliter from the lotion, against 7.1 for avobenzone in the same lotion, and after the last dose its level halved about every 79 hours. 4
Cosmetics Europe, the European cosmetics industry association, paid for a 2023 reanalysis of the FDA trials by scientists from Beiersdorf, Procter and Gamble, and L'Oréal. They compared seven sunscreen chemicals with a blood level of 1 micromolar, below which, by their method, an untested chemical is taken to pose little risk, and found every one "except oxybenzone" an order of magnitude below it. 37 A 2024 computer model paid for by Procter and Gamble and Estée Lauder, "manufacturers of facial sunscreen products", predicted that of seven sunscreen chemicals used on the face alone, oxybenzone would reach the highest level in the blood. 38
In Lund, Sweden, a university group screened saliva from 432 people for broken copies of the filaggrin gene, which helps build the skin's outer barrier, and found 28 carriers. They put 4.7 milligrams of pure oxybenzone in alcohol on a square of upper arm in 23 carriers and 31 non-carriers, covered it with foil for four hours, and collected urine for two days. Oxybenzone entered the carriers' skin at a 32 percent higher rate. The volunteers already had oxybenzone in their urine before the test, a median of 1.88 nanograms per milliliter in carriers and 4.45 in the others. 39
On nude mouse skin in the laboratory, lamp doses of UVA or UVB had a negligible effect on how much oxybenzone passed through, and every absorption study in people that we found was run indoors. 40
People who use no sunscreen carry oxybenzone too; it is in lotions, lip balm, mouthwash, indoor air, and clothing
From February to December 2013, 300 young men in Denmark gave urine, blood, and semen within the same hour, and only six of them said they had used sunscreen in the two days before. Oxybenzone was in the urine of 96 percent of them and in 27 percent of the semen samples, at levels ten to a hundred times lower than in urine. 41
In a 2014 survey, researchers bought 231 personal care products in China and the United States and found oxybenzone in 81 percent of them, with the highest levels in skin lotions, sunscreens among them. 6 In the 2009 to 2012 national survey, American adults who said they always used sunscreen had 510 percent more oxybenzone in their urine than those who never did, and daily mouthwash users had 42 percent more than people who never used mouthwash. 42 Among Californian families, adults who used shaving cream had 1.85 times as much. 43
In 2014 researchers sampled the air of 81 indoor places around Albany, New York, and found oxybenzone in every one, highest in cars and then in barber shops, public places, and homes, though they estimated that breathing supplies under 5 percent of a person's intake. 44 A Danish and American team later tested whether clothing could deliver it. They melted about 20 grams of oxybenzone onto pans in "a small closet-sized, sealed dosing chamber" of foam board and aluminum foil, hung new cotton T-shirts from a Lyngby department store in it for 32 days, and had three volunteers wear them for three hours. Over the next day the three passed 12, 9.9, and 82 micrograms of oxybenzone and its metabolite that the authors attributed to the shirts. 45
Southern California firefighters tested at routine fitness examinations in 2010 and 2011 had about five times the oxybenzone of comparable men in the national survey. The authors pointed to plastic parts of their protective equipment, which may use oxybenzone as an ultraviolet stabilizer, and to turnout coats treated against ultraviolet. 46 In 2025 an analysis of 3,072 American women from national survey data found that minority women dissatisfied with their bodies carried more oxybenzone "independent of sunscreen usage", which the authors suggested came from other personal care products. 47
In Salinas, "a small city in an agricultural region" of northern California, 100 Latina teenage girls helped design a study with researchers from the University of California, Berkeley. The girls chose replacement products labeled free of oxybenzone, parabens, phthalates, and triclosan and used only those for three days. Their urine oxybenzone fell by 36 percent on average; the true fall could have been anywhere from about 16 to 51 percent, and the study had no comparison group. 48
Oxybenzone reaches cord blood and milk at lower levels than the mother's blood and urine; pooled birth-weight studies found no link
In 2019 the FDA wrote that high levels of oxybenzone in mothers' urine had been associated with lower birth weight in girls and higher birth weight and head size in boys, and called the association "particularly concerning given the widespread exposure of the U.S. population to oxybenzone". 2 One source was a Mount Sinai study in New York, where 404 women gave urine in the third trimester between 1998 and 2002. Higher oxybenzone went with lower birth weight in girls and higher birth weight in boys. 49
A French study of 191 mothers of baby boys found that each 2.7-fold rise in urine oxybenzone went with 26 grams more birth weight. Its 95 percent confidence interval, the range the true value most likely lies in, ran from 2 grams less to 54 grams more. 50 In 2020 a group at Anhui Medical University pooled ten studies of oxybenzone and birth size in a meta-analysis, a study that combines earlier studies into one estimate, and found no association with birth weight, length, or head circumference. 51
In Tianjin, China, in 2010, blood was drawn from mothers within an hour before delivery and from the umbilical cord at birth. Across 22 pairs, oxybenzone was found in 12 cord samples and 7 of the mothers' samples, and where both could be measured the cord held about half the mother's level. 52 In North Carolina, 34 nursing women recruited for the Environmental Protection Agency gave milk, urine, and blood at the agency's clinic in 2004 and 2005. Oxybenzone was in about half the milk samples and under 30 percent of the blood samples, milk carried 57 to 738 times less than the same woman's urine, and the authors found that exposure "could not be predicted by single daily collections". 53 Studies from Denmark, Guangzhou, Basel, and Barcelona are on the sunscreen page.
In Nanjing, researchers compared one urine sample from each of 101 mothers of children with Hirschsprung's disease, in which nerve cells are missing from part of the bowel, with samples from 322 other mothers. Against the lowest-exposure group, mothers in the middle and highest groups had 2.4 and 2.6 times the odds of a child with the disease, with confidence intervals running from about 1.1 to 5.2 and 1.2 to 5.9. The median oxybenzone in these mothers' urine was 0.08 nanograms per milliliter. The samples were taken after the children were born, and the authors assumed that the mothers' habits had not changed "for several months prior to the sample collection". 54
In 2019 Joseph DiNardo and Craig Downs wrote a commentary on the Nanjing study advising pregnant women to use "oversized umbrellas/cabanas". Downs, whose Haereticus Environmental Laboratory led the coral larvae study on the sunscreen page, disclosed that the laboratory had received $1,100 from the W.S. Badger Company to cover 105 T-shirts for a "Save The Reef" rally in Key West. 55
Studies of urine oxybenzone and hormones in people point in more than one direction
In 2016 two scientists at the federal Agency for Toxic Substances and Disease Registry compared urine oxybenzone with blood testosterone in children and teenagers from the 2011 to 2012 national survey. Boys aged 12 to 19 in the top quarter, above 48.7 nanograms per milliliter, had 37 percent less testosterone than boys in the bottom quarter, and the true difference could lie anywhere from about 2 to 59 percent less. Girls showed no consistent link. The authors noted that testosterone in young men can be up to 50 percent lower in the evening than at its morning peak, and called for more studies "because of the limitations inherent to the cross-sectional study design". 8
In 1,239 girls enrolled at ages 6 to 8 in New York City, Cincinnati, and the San Francisco Bay Area and examined every year for seven years, those in the top fifth of urine oxybenzone at enrollment began breast development 5 to 6 months later than those in the bottom fifth. The authors suggested oxybenzone might act as an "antiadipogen", a substance that works against the growth of fat cells. 9 When the Cincinnati researchers reanalyzed 282 of their own girls in 2022, those in the second quarter of oxybenzone began breast development earlier than those in the lowest, and the authors wrote that the finding "may be a random effect". 56
In the ENDO study of 600 women in Utah and California who had surgery or pelvic imaging between 2007 and 2009, oxybenzone was in 99 percent of urine samples and ran highest in July and August. It showed no significant trend with endometriosis, while its metabolite benzophenone-1 did in the women who had surgery. The models adjusted for each woman's "natural hair color at age 18 years", red, blond, or brown or black. 57
Among 65 young Danish men carrying filaggrin mutations, higher urine oxybenzone went with higher testosterone and estradiol and with lower follicle-stimulating hormone, which drives sperm production, while in 130 men without the mutations there was no such link. 58 At a Boston fertility clinic, 142 women gave an average of 2.7 urine samples each between 2009 and 2017, and oxybenzone showed no link with the number of egg follicles or with follicle-stimulating hormone in the group as a whole. 59
A Seoul group working with 1,829 Americans in the 2007 to 2008 national survey found oxybenzone, bisphenol A, and a phthalate each linked to lower thyroid hormones. Because the three rose and fell together in the same people, the group put all three into one model, and oxybenzone's link held while bisphenol A's did not. 60 In 2019 the FDA wrote that the endocrine effects of oxybenzone in people "have been studied with inconclusive results". 2
A two-year feeding study found equivocal evidence of cancer in rats and none in mice
The cancer study that the National Cancer Institute had asked for in 1979 was published by the National Toxicology Program in May 2020. Pregnant rats ate oxybenzone from the sixth day of pregnancy, and their offspring ate it for 105 weeks after weaning, at 1,000, 3,000, or 10,000 parts per million of their food, about 58 to 632 milligrams per kilogram a day. Mice ate the same concentrations for two years. 15
In male rats, malignant meningiomas, tumors of the lining of the brain, appeared in 0, 1, 3, and 0 of 50 animals from the unexposed group up to the highest dose. In female rats, benign thyroid tumors called C-cell adenomas ran at 5, 11, 17, and 10 of 50, and polyps of the womb at 8, 15, 18, and 10 of 50, while cancer of the womb was significantly less common at the middle dose. The program called this "equivocal evidence" of cancer in rats of both sexes, its term for "a marginal increase of neoplasms that may be chemical related", and found "no evidence" in mice. Bacterial tests for damage to genes were negative. 15
A 2020 Michigan State study fed oxybenzone, about 70 milligrams per kilogram a day, to mice carrying transplanted breast tissue that lacks the tumor-suppressor gene p53 and so tends to form tumors. On a lifelong low-fat diet oxybenzone protected against one kind of breast tumor; on a high-fat diet begun in adulthood it promoted the same kind. The authors wrote that the dose gave urine levels "similar to humans subjected to heavy topical sunscreen exposure". 61
We found no study that followed people who used oxybenzone sunscreen and counted cancers, and 4 of the 517 oxybenzone studies in our registry are about cancer at all. The sunscreen industry's 2025 review, which argued that two-year rodent cancer studies of sunscreen chemicals were unnecessary, covered six of them (avobenzone, ensulizole, homosalate, octinoxate, octisalate, and octocrylene) and did not include oxybenzone. 62
Reef laws spread after 2018 on laboratory tests of coral larvae and cells
In 2008 an Italian group led by Roberto Danovaro added whole sunscreens to branches of coral in three oceans and the Red Sea, and the corals bleached, losing the algae that live in their tissue. The group estimated how much sunscreen reaches reefs from 78 million tourists a year in reef areas, two applications a day of 20 grams each over a five-day trip, and at least a quarter washed off, for 4,000 to 6,000 tons a year. They noted that they had tested sunscreen "containing concentrations of UV filters higher than those reported in most natural environments". 63
The smallest number in the 2016 coral study led by Craig Downs, 0.062 micrograms per liter or about 62 parts per trillion, is the concentration that killed a fifth of isolated coral cells in four hours in a dish under light, for the most sensitive of seven species. Half the larvae of the one species tested whole, Stylophora pistillata, died within 24 hours in light at 139 micrograms per liter, more than 2,000 times as much. 64
In 2022 a study in Science found that a sea anemone and a mushroom coral kept under simulated sunlight attached a sugar to oxybenzone, and that this sugar-bound form was a strong photo-oxidant, a chemical that damages tissue in light, while oxybenzone itself protected against ultraviolet damage. Anemones that lacked their algal partners died more, which the authors took to suggest "an enhanced risk from oxybenzone to corals bleached by rising temperatures". 65
Hawaii's law, passed in 2018 and in force from 2021, bans selling sunscreen with oxybenzone or octinoxate without a prescription from a licensed provider, and it does not cover cosmetics for the face. It lists 14 other names for oxybenzone, among them Eusolex 4360, Uvinul M-40, and USAF Cy-9. 12 Key West's city commission adopted a ban in February 2019, three weeks after hearing Carys Mitchelmore of the University of Maryland, who called herself "a Professor and independent scientist", tell it that "there is very limited data on the impacts of oxybenzone and octinoxate on corals". 66; 67 Her 2019 survey of Oahu's coastal water, described on the sunscreen page, was funded by the Personal Care Products Council, the cosmetics industry's trade association, which also sent the commission a letter of opposition. 68; 66
Maui County's council voted unanimously in November 2021 to ban the sale, distribution, and use of all non-mineral sunscreens from October 2022. Its announcement said that zinc oxide and titanium dioxide were the only sunscreen ingredients the FDA deemed "generally recognized as safe and effective"; the FDA had proposed that in 2019 and not ruled. 69; 2 Thailand has banned bringing or using sunscreen with oxybenzone, octinoxate, 4-methylbenzylidene camphor, or butylparaben in its national parks since August 2021, with fines of up to 100,000 baht. 70 In May 2021 the FDA announced that it would consider an environmental impact statement on oxybenzone and octinoxate, and we found no draft in the Federal Register. 71
Europe and Britain cut oxybenzone to 2.2 percent in body products; the FDA has not ruled
The European Union allowed oxybenzone at up to 10 percent until 2017, when it cut the limit to 6 percent, relying on a 2008 opinion that 6 percent posed no risk "apart from its contact allergenic and photoallergenic potential". 72 In 2021 the EU's Scientific Committee on Consumer Safety calculated a margin of safety for sunscreen use, the ratio between the highest dose that caused no harm in a chosen animal study and the dose a person would absorb. 17
The committee took the animal dose from a study in which rats were fed oxybenzone during pregnancy and nursing. At 3,000 parts per million their male offspring had fewer spermatocytes, the cells that become sperm, which the committee said might be a hormone effect, and at 1,000 parts per million, 67.9 milligrams per kilogram a day, they showed none. The committee's model person weighed 60 kilograms, spread 18 grams of sunscreen a day, and absorbed 9.9 percent of the oxybenzone, which at 6 percent gave a margin of 38 for a body cream. The committee judged 6 percent safe in face creams, hand creams, and lipsticks, and 2.2 percent safe in body products. 17
On hormones the committee judged the evidence "inconclusive, and at best equivocal". 17 The EU's 2022 regulation cited "concerns related to potential endocrine disrupting properties", adopted the committee's limits, and let products made to the old rules be placed on the market until January 2023. 10 Britain adopted the same limits from 21 January 2026, the government stating that there was "a potential risk to human health". 11 In 2025 Denmark, evaluating oxybenzone under the EU chemicals law, concluded that it is an endocrine disruptor for human health and the environment and said it intends to propose that classification; we found no adopted EU classification. 73
Australia's Therapeutic Goods Administration, which regulates sunscreen as a medicine, proposed in July 2025 that some products with oxybenzone or homosalate be reformulated, and said in the same release: "All sunscreens available in Australia are safe." 74
In the United States the FDA's 2019 proposal put oxybenzone in its third category, needing more data. It asked for an absorption trial that also measured oxybenzone's metabolites, for studies of development and reproduction "that fully investigate its potential endocrine-disrupting effects", and for cancer studies on the skin and by mouth. It asked whether oxybenzone sunscreens should be kept from children under two, citing a 2006 Swedish report that children that young have not fully developed the enzymes believed to break it down. It also wrote that the new information on absorption was "inadequate, by itself, to support an affirmative conclusion" that the products "are not safe". 2
A 2020 law, the CARES Act, turned the conditions of a 1999 rule into the standing order, under which oxybenzone may be sold at up to 6 percent, and the FDA restated its proposal in a 2021 proposed order. By September 2026 the FDA had removed PABA and trolamine salicylate, added bemotrizinol, and not ruled on oxybenzone. The EU committee's 2021 opinion summarized the FDA's 2019 proposal as "category III: not safe for use as UV filter". The FDA's own question-and-answer page says that the 2021 proposal "does not represent a conclusion by the FDA that the sunscreen active ingredients proposed as having insufficient data are unsafe for use in sunscreens". 3; 17
Misconceptions
What people believe
- The FDA has banned oxybenzone or found it unsafe.
- Oxybenzone is banned in Europe.
- Oxybenzone has been shown to disrupt hormones in people.
- Oxybenzone has been shown to cause cancer.
- The oxybenzone in people's urine comes from sunscreen.
- Oxybenzone kills coral reefs at 62 parts per trillion.
- Hawaii banned chemical sunscreens.
What the studies show
- The FDA proposed in 2019 that it lacked the data to call oxybenzone safe and effective and has not ruled. It says the proposal is not a conclusion that the ingredient is unsafe. 2; 3
- The EU and Britain allow it at up to 6 percent in face, hand, and lip products and 2.2 percent in body products. 10; 11
- Urine studies link oxybenzone with hormone levels in different directions, from lower testosterone in boys to later breast development in girls, and the EU's safety committee called the hormone evidence "inconclusive, and at best equivocal". 8; 9; 17
- A two-year feeding study found equivocal evidence of cancer in rats and none in mice, and we found no study that counted cancers in people who used it. 15
- It is also in lotions, lip balm, shaving cream, mouthwash, indoor air, and clothing, and only 6 of 300 young men in Denmark whose semen was tested had used sunscreen in the two days before. 6; 43; 42; 44; 45; 41
- 62 parts per trillion is the level that killed a fifth of isolated coral cells from the most sensitive of seven species in four hours in a dish. 64
- Hawaii's law covers two sunscreen chemicals, oxybenzone and octinoxate, and allows sale with a prescription. 12
Questions people ask
Is oxybenzone safe?
The EU's safety committee found 6 percent oxybenzone not safe in body sunscreens and 2.2 percent safe, and the EU and Britain now cap it there. The FDA said in 2019 that it lacked the data to call oxybenzone safe and effective and has not ruled. No study has shown that oxybenzone causes disease in people. 17; 11; 2
Does oxybenzone cause cancer?
No study in people has tested it. In a two-year feeding study, rats showed "equivocal evidence" of cancer and mice showed none. 15
Is oxybenzone banned in Europe or the United States?
No. The EU and Britain limit it to 6 percent in face, hand, and lip products and 2.2 percent in body products, and the FDA allows it at up to 6 percent. Hawaii bans its sale without a prescription, and Thailand bans it in national parks. 10; 11; 3; 12; 70
Does oxybenzone disrupt hormones?
It acts as a weak estrogen in breast cancer cells and in rats fed large doses. In people, urine studies have linked it to lower testosterone in boys, higher testosterone in young men with a skin-barrier mutation, and later breast development in girls, and the EU's safety committee called the evidence "inconclusive, and at best equivocal". 7; 8; 58; 9; 17
Is oxybenzone bad for coral reefs?
In the laboratory it harmed coral larvae and isolated coral cells. How much it harms reefs in open water has not been measured. 64
Is oxybenzone safe during pregnancy?
It reaches cord blood at about half the mother's level, and a 2020 pooled analysis of ten studies found no link between mothers' urine levels and birth size. We found no study that tested whether sunscreen use in pregnancy harms a baby. 52; 51
Can you be allergic to oxybenzone?
Yes, to the chemical on the skin and to the chemical in light, which is called photoallergy. Of 23,908 North American patients patch tested from 2001 to 2010, 82 reacted to it. 2
How long does oxybenzone stay in the body?
In the 2020 FDA trial its level in the blood halved about every 79 hours after the last application. 4
What is another name for oxybenzone?
Benzophenone-3, often shortened to BP-3, and 2-hydroxy-4-methoxybenzophenone. Trade names include Eusolex 4360 and Uvinul M-40. 12
What we do not know
Nobody knows whether the oxybenzone that people carry in their blood does anything to them. The studies in people compare a urine sample with a hormone level or a diagnosis, in people who also take in oxybenzone from lotions, lip balm, air, and clothing, and their results point in different directions. We found no trial that gave some people oxybenzone sunscreen and others none and followed their health.
What oxybenzone breaks into on sunlit skin, in pools, and in the sea, and whether those products do anything, rests on one real-sun study in eight people, one skin model under a lamp, and the anemone study of 2022. What oxybenzone does to reefs in open water has not been measured.
Every absorption study in people that we found was run indoors, and none measured oxybenzone in the blood after a day of real sun, heat, sweat, and seawater. Among the 517 oxybenzone studies in our registry we found none that put an oxybenzone sunscreen on a child and measured it in the child's blood or urine, though the FDA asked in 2019 whether such sunscreens should be kept from children under two.
Key studies
- Katz, 1970. Nine men in an hour of natural sun: an oxybenzone cream protected when applied after swimming, and no product protected consistently when applied before. 22
- FDA advisory panel, 1978. Judged oxybenzone safe and effective at 2 to 6 percent; 96.51 percent recovered from the forearms of 14 people after four hours. 13
- National Toxicology Program, 1992, Worcester. Rats fed 50,000 parts per million for 13 weeks had lower sperm density, and so did mice given it on the skin. 14
- Knobler and colleagues, 1989, New York. Four patients photoallergic to oxybenzone, one of them treated with PUVA. 23
- Journe and colleagues, 1999, Toulouse. 27 of 57 sunscreen allergies among 370 patients were to oxybenzone. 16
- Schallreuter and colleagues, 1996, England. Oxybenzone oxidized on skin in 15 minutes of May sun. 29
- Hanson and colleagues, 2006, Riverside. After an hour on a skin model under a lamp, three sunscreen chemicals made more reactive oxygen species than none. 30
- Schlumpf and colleagues, 2001, Zurich. A weak estrogen in breast cancer cells and in rats fed 1,525 milligrams per kilogram a day. 7
- LaPlante and colleagues, 2018, Amherst. Mice fed 3,000 micrograms per kilogram a day in pregnancy and nursing had denser mammary ducts. 33
- Gonzalez and colleagues, 2002, Göteborg. About 0.4 percent of one whole-body application appeared in urine over 48 hours. 35
- Matta and colleagues, 2020, West Bend. All 24 oxybenzone users were above 0.5 nanograms per milliliter within two hours; the level halved about every 79 hours. 4
- Rietz Liljedahl and colleagues, 2021, Lund. Carriers of filaggrin mutations absorbed oxybenzone at a 32 percent higher rate. 39
- Morrison and colleagues, 2017, Lyngby. T-shirts that had hung in oxybenzone-laden air delivered it to the people who wore them. 45
- Frederiksen and colleagues, 2021, Copenhagen. Oxybenzone in 27 percent of semen samples from young men, 6 of 300 of whom had used sunscreen. 41
- Harley and colleagues, 2016, Salinas. Three days of swapped products cut urine oxybenzone by 36 percent. 48
- Wolff and colleagues, 2008, New York. Mothers' urine oxybenzone went with lower birth weight in girls and higher in boys. 49
- Zhong and colleagues, 2020, Hefei. Ten pooled studies found no link with birth size. 51
- Scinicariello and Buser, 2016, national survey. Boys in the top quarter had 37 percent less testosterone. 8
- Wolff and colleagues, 2015, three US cities. Girls in the top fifth began breast development 5 to 6 months later. 9
- National Toxicology Program, 2020. Equivocal evidence of cancer in rats and no evidence in mice. 15
- Downs and colleagues, 2016. Oxybenzone killed and deformed coral larvae and cells in the laboratory. 64
- Vuckovic and colleagues, 2022. A sea anemone and a coral turned oxybenzone into a form that damages them in light. 65
- Scientific Committee on Consumer Safety, 2021. A margin of safety of 38 for a 6 percent body sunscreen; 2.2 percent judged safe. 17
Definitions
- Benzophenone-1. The main metabolite of oxybenzone in urine, measured alongside it in many studies.
- Benzophenones. A family of chemicals that absorb ultraviolet light. Oxybenzone is benzophenone-3.
- Confidence interval. The range within which the true value of an estimate most likely lies, usually given at 95 percent.
- Contact allergy. An allergic skin reaction to a chemical touching the skin, with or without light.
- Cross-sectional study. A study that measures exposure and outcome at the same time, so it cannot show which came first.
- Endocrine disruptor. A chemical that interferes with the body's hormones in a way that causes harm. European assessors disagree on whether oxybenzone meets the definition.
- Equivocal evidence. The National Toxicology Program's term for "a marginal increase of neoplasms that may be chemical related".
- Estradiol. The main estrogen in the human body.
- Estrogen. A hormone that drives female development and the growth of some breast cancers.
- Filaggrin. A protein that helps build the outer barrier of the skin. Some people carry broken copies of its gene.
- Follicle-stimulating hormone. A pituitary hormone that drives egg development in women and sperm production in men.
- Generally recognized as safe and effective. The FDA's standard for an ingredient that can be sold without a prescription.
- Glucuronic acid. A sugar acid the body attaches to many chemicals so that the kidneys can clear them.
- Margin of safety. The ratio between the highest dose that caused no harm in an animal study and the dose a person is estimated to absorb.
- Meta-analysis. A study that pools the results of earlier studies into one estimate.
- Metabolite. A chemical the body makes from another one.
- Micromolar. A millionth of a mole per liter, a unit of concentration. A picomolar is a million times smaller.
- Oxybenzone. A sunscreen chemical, also called benzophenone-3, that absorbs UVB and part of UVA.
- Parts per million. A unit of concentration. Feed with 50,000 parts per million of a chemical is 5 percent that chemical.
- Photoallergy. An allergic reaction to a chemical that happens only where light falls on the skin.
- Photopatch test. A test for photoallergy in which suspect chemicals are taped to the back in two sets and one set is given UVA from a lamp.
- PUVA. A treatment that combines a psoralen drug, such as methoxsalen, with UVA light.
- Raman spectroscopy. A method that identifies molecules by how they scatter laser light, used here to follow a chemical in living skin without cutting it.
- Reactive oxygen species. Unstable molecules containing oxygen that can damage DNA, proteins, and cell membranes.
- Solar simulator. A lamp built to give off a spectrum close to that of sunlight.
- SPF. Sun protection factor. The ratio of the ultraviolet dose that reddens skin under 2 milligrams per square centimeter of a sunscreen to the dose that reddens bare skin, measured under a lamp.
- Spermatocyte. A cell in the testes on its way to becoming sperm. A spermatid is a later stage.
- UVA. Ultraviolet light from 315 to 400 nanometers, most of the ultraviolet that reaches the ground.
- UVB. Ultraviolet light from 280 to 315 nanometers. It causes most sunburn.
Statistics
In 30 urine samples from anonymous adult volunteers collected 2000 to 2004, only 3 percent of the oxybenzone came out in its free, unbound form. 36
In the same 30 adult urine samples, oxybenzone bound to glucuronic acid made up 84.6 percent of the total excreted. 36
In 24 pooled blood serum samples made from 936 US children aged 3 to 11 in the 2001-2002 national survey, oxybenzone was detected in 15 pools. 75
In those pooled serum samples from US children, mean oxybenzone concentrations ranged from 0.5 to 5.9 micrograms per liter, and it was found in every demographic group except non-Hispanic Black children. 75
In 33 young Danish men who each gave eight urine samples over three months, oxybenzone levels were fairly stable within each man, with intraclass correlations of 0.69 to 0.80, against 0.10 to 0.42 for bisphenol A. 76
In 24-hour urine from 129 healthy Danish children and adolescents aged 6 to 21, the median oxybenzone concentration was 1.41 ng/mL and the highest was 162 ng/mL. 77
Among 23 adults in Tianjin, China, who gave matched blood and urine, oxybenzone was found in 19 blood and 15 urine samples, at up to 4.41 ng/mL in blood and 45.2 ng/mL in urine. 52
In 166 urine samples from children and adults, geometric mean oxybenzone was 9.97 ng/mL in US children and 15.7 ng/mL in US adults, against 0.622 and 0.977 ng/mL in Chinese children and adults. 78
In urine from 625 women in Utah and California, oxybenzone was detected in 99.0 percent of samples. 57
In fat tissue from 20 people in New York City, oxybenzone had a geometric mean of 43.4 ng per gram wet weight and a maximum of 4,940 ng per gram. 79
In 24 pools of urine, each from 100 people in Queensland, Australia, oxybenzone had a geometric mean of 61.5 ng/mL. 80
Among 34 nursing women in North Carolina, oxybenzone in breast milk was 57 to 738 times lower than in the same woman's urine. 53
In the North Carolina milk study, oxybenzone was detectable in about half of milk samples and in less than 30 percent of serum samples, with a mean of 3.7 µg/L in the 7 of 10 milk samples where it was found. 53
In urine from 168 Korean adults tested in 2014, the mean oxybenzone level was 5.87 ng per gram creatinine, and it rose with the number of cosmetic products used. 81
In urine from 101 Southern California firefighters, the geometric mean oxybenzone level was about five times that of a comparable group in the US national survey. 46
Among the 101 firefighters, a higher body fat percentage went with lower urine oxybenzone. 46
Across 10,232 participants in five US national survey cycles from 2003 to 2012, urine oxybenzone showed no statistically significant overall change, though it trended upward from 2005-2006. 82
In post-mortem brain tissue, oxybenzone was not among the chemicals found in 24 hypothalamus samples and was detected in a single one of 12 white-matter samples. 83
In fat tissue from 144 hospital patients in southern Spain, oxybenzone was detected in 79.2 percent of samples, at a median of 0.60 ng per gram. 84
In urine from 98 people in households in eastern China, oxybenzone was the most abundant of four UV filters measured, at a median of 1.89 micrograms per gram of creatinine. 85
In Hong Kong tap water and distilled bottled water, oxybenzone was found in every sample, at geometric means of 9.64 and 14.5 nanograms per liter. 86
Of 53 Hong Kong children aged 4 to 6 whose urine was tested for UV filters, only two had used sun cream, though the filters were found widely. 86
Among 137 pairs of US adults living in the same home, urine oxybenzone levels were correlated between housemates, with a tau of 0.31, second only to 2,5-dichlorophenol. 87
In paired samples from 300 young Danish men collected in 2013, oxybenzone was detected in 27 percent of seminal fluid samples, at levels 10 to 100 times lower than in urine. 41
Only 6 of the 300 Danish men reported using sunscreen in the 48 hours before their samples were taken. 41
In 50 female beauticians, median urine oxybenzone was 2.1 ng/mL before a work shift and 2.65 ng/mL after it, against 0.22 ng/mL in 35 housewives. 88
Among 69 public figures from six European countries who gave spot urine, the highest oxybenzone level was 1,915.1 ng/mL, and women had higher levels than men. 89
When 11 volunteers applied the recommended amount of a commercial oxybenzone sunscreen once, they excreted an average of 11 mg of oxybenzone in urine over 48 hours, about 0.4 percent of the amount applied. 35
Some of the 11 volunteers were still excreting oxybenzone in their urine 48 hours after a single sunscreen application. 35
In three women aged 22 to 42 who put 2 mg/cm2 of a children's SPF 30 sunscreen with 6 percent oxybenzone on their arms and back, up to about 1 percent of the applied oxybenzone and its metabolites came out in urine. 32
Three people who wore, for 3 hours, cotton shirts that had been exposed for 32 days to air laden with oxybenzone excreted 12, 9.9 and 82 micrograms of oxybenzone and its metabolite BP-1 in the next 24 hours, attributed to the shirts. 45
In a skin exposure test on 23 Swedish carriers of filaggrin null mutations and 31 non-carriers, oxybenzone was absorbed through the skin with a 32 percent higher rate constant in the carriers. 39
In the same Swedish skin test, filaggrin null carriers had a 77 percent higher oxybenzone absorption rate constant than non-carriers with the highest filaggrin copy numbers. 39
Re-analysing the FDA maximal-use trial blood data for seven filters against an internal safety threshold of 1 micromolar, the authors found every filter except oxybenzone an order of magnitude below it. 37
On nude mouse skin irradiated with lamp UVA at 24 or 39 J/cm2 or UVB at 150 to 250 mJ/cm2, UV exposure had a negligible effect on how much oxybenzone passed into and through the skin. 40
On pig-ear skin in the laboratory, about 0.5 percent of oxybenzone applied at 2 mg/cm2 in a 10 percent water-in-oil sunscreen passed through the skin in the first hour. 90
From their pig-skin data, the authors calculated a margin of safety of 42 for whole-body use of a 10 percent oxybenzone sunscreen at 0.5 mg/cm2, below the benchmark of 100, while octinoxate and avobenzone scored 485 and 192. 90
In MCF-7 breast cancer cells, oxybenzone increased cell growth with a half-maximal concentration of 3.73 micromolar, and its maximum effect reached the level of estradiol. 7
In immature Long-Evans rats fed UV filters in powdered feed for 4 days, oxybenzone increased uterine weight only weakly, at 1,525 mg/kg a day, against an ED50 of 309 mg/kg a day for 4-MBC. 7
Of 253 industrial chemicals screened in AR-EcoScreen cells, 9 blocked the androgen receptor, and oxybenzone was one of them, listed sixth of the nine by potency. 91
Among 600 women examined for endometriosis in Utah and California, urine oxybenzone showed no significant trend with the diagnosis; only its metabolite 2,4-dihydroxybenzophenone did, with an odds ratio of 1.19 in the surgical group. 57
In 1,239 US girls followed from age 6 to 8, those in the top fifth of urine oxybenzone began breast development 5 to 6 months later than those in the bottom fifth, a hazard ratio of 0.80. 9
In 495 women who later had surgery to check for fibroids, geometric mean urine oxybenzone was 11.31 µg/g in women with fibroids and 6.10 µg/g in those without, but no chemical showed a significant odds ratio for fibroids after adjustment. 92
In 143 healthy premenopausal women tracked over two menstrual cycles, a combined urine factor for oxybenzone and BP-1 went with lower estradiol, FSH and LH, with coefficients of -0.16, -0.12 and -0.17. 93
Among 65 young Danish men carrying filaggrin skin-barrier mutations, higher urine oxybenzone went with higher testosterone and estradiol and lower FSH, while no such link appeared in 130 non-carriers. 58
Of 215 university men aged 18 to 23 in southern Spain, 97 percent had at least one of five benzophenone filters in their urine, and higher oxybenzone went with slightly higher serum FSH (beta 0.04). 94
Among 142 women seeking fertility treatment in Boston, oxybenzone was found in 98 percent of urine samples at a geometric mean of 85.9 µg/L, and it showed no link with antral follicle count or FSH in the full group. 59
In the Boston fertility study, among women aged 35 or younger, each unit rise in log oxybenzone went with an antral follicle count 0.91 times as high. 59
In 1,829 Americans aged 12 and over in the 2007-2008 national survey, urine oxybenzone stayed linked with lower serum thyroid hormones after the model accounted for chemicals that may share its sources. 60
In 155 samples of ovarian follicular fluid from 111 couples at a Danish fertility clinic, oxybenzone was the only benzophenone of six measured that could be detected. 95
Of 54 consecutive patients with suspected photosensitivity tested in Tours, France, in 1989-1990, oxybenzone caused 4 cases of contact allergy and 3 of photocontact allergy, 13 percent of the patients. 96
Of 58 customers who complained to Swedish pharmacies about skin problems from sunscreens, 27 were fully investigated, and contact or photocontact allergy to oxybenzone caused severe dermatitis in 3. 97
Among 370 patients with suspected photodermatitis tested in Toulouse from 1990 to 1994, 57 (15.4 percent) had contact or photocontact allergy to sunscreens, and 27 of those reactions were to oxybenzone. 16
Of 207 patients photopatch tested in Athens from 1992 to 2006, 28 (13.52 percent) had photocontact reactions, and oxybenzone caused 12.5 percent of them. 98
Of 83 patients photopatch tested in Coimbra, Portugal, from 2003 to 2007 with 5 J/cm2 of lamp UVA, 10 relevant reactions were to UV filters, including 3 patients reacting to oxybenzone. 99
Of 27 patients who said they were allergic to sunscreen, 11 agreed to photopatch testing, 8 tested negative, and one had relevant photopatch reactions to oxybenzone and padimate O. 26
Among patients photopatch tested at Toronto Western Hospital from 2001 to 2010, 54 (33.8 percent) had at least one photoallergic reaction, and oxybenzone was the most common relevant photoallergen. 100
Compared with pooled North American data from 1996 to 2006, oxybenzone was one of only 3 allergens that tested positive significantly more often in 2007-2008, among 5,085 patients. 101
Of 1,527 patients in a Canadian patch test database, 8 with no history of sunscreen allergy reacted to oxybenzone, and allergic contact dermatitis to sunscreen overall was found in 0.8 percent. 102
Of 100 patients photopatch tested in Bogota, Colombia, with 5 J/cm2 of lamp UVA, 15 had 20 photopatch reactions, 95 percent caused by UV filters and 55 percent by oxybenzone. 25
In the Bogota series, 8 of the positive photopatch reactions (53.3 percent) appeared only at the day 6 reading. 25
Of 35 patients with photosensitivity confirmed by photopatch testing in La Plata, Argentina, in 2015-2016, 5 (14.28 percent) reacted to oxybenzone, 4 of them only at sites irradiated with 5 J/cm2 of UVA. 103
Of 7 patients with photodermatitis from the painkiller gel ketoprofen, 4 also had positive UVA photopatch tests to oxybenzone. 104
A 40-year-old childcare assistant in Liverpool had hives from several sunscreens, then anaphylaxis with syncope after a false-tan product, traced to oxybenzone. 27
Oxybenzone was found in all 81 indoor air samples taken around Albany, New York, in 2014, at 0.19 to 72.0 ng per cubic meter, with a geometric mean of 2.67. 44
In the Albany air survey, cars had the highest oxybenzone levels, a geometric mean of 10.7 ng per cubic meter, followed by barber shops at 6.57 and homes at 3.27. 44
In 38 house dust samples from California, oxybenzone was one of only ten compounds, out of 144 quantified, with a median above 10,000 ng per gram of dust. 105
Of 231 personal care products bought in China and the United States, 81 percent contained oxybenzone, at up to 0.148 percent, with skin lotions, including sunscreen lotions, the highest at a geometric mean of 548 ng/g. 6
From product levels and use rates, the authors estimated a geometric mean oxybenzone intake through the skin of 24.4 micrograms a day for adult women in the US, against 0.978 for women in China. 6
A US SPF 50 sunscreen containing oxybenzone and homosalate, added to seawater at 50 microliters per liter for 24 hours, caused abnormalities in 100 percent of sea urchin embryos; the test used the whole product. 106
Of ten suspected hormone-disrupting chemicals tracked in urine and in wastewater from five treatment plants, oxybenzone and BP-1 were the only two found in urine, and they were among three found in wastewater. 107
When 19 volunteers got three minimal erythema doses of UVB on three days in a row, those who first applied an SPF 29 sunscreen containing oxybenzone kept their contact allergy response, no different from 10 unirradiated controls. 108
In skin samples given UV after a 2 mg/cm2 layer of formulation, oxybenzone first cut reactive oxygen species in the living epidermis, but after 60 minutes on the skin the filters generated more of them than skin without any filter. 30
In 1,576 urine samples from South Koreans aged 6 to 89, collected in the summers of 2010 and 2011, oxybenzone was detected in fewer than 25 percent. 109
Among 3,529 US adults in the 2009-2012 national survey, those who said they always used sunscreen had urine oxybenzone 510 percent higher than those who never did. 42
In the same 3,529 US adults, daily mouthwash users had urine oxybenzone 42 percent higher than people who never used mouthwash. 42
Among 52 children and 71 adolescents in Taiwan, oxybenzone was detected in 8.1 percent of urine samples overall, never in the children, and only in adolescent girls. 110
In first-morning urine from about 515 German children and teenagers aged 3 to 17, sampled 2014 to 2017, oxybenzone could be quantified in 35 percent, and its geometric mean fell below the limit of quantification. 111
Among 3,072 US women in national survey data from 2003 to 2016, urine oxybenzone averaged 59 percent higher in Mexican American women and 16 percent higher in non-Hispanic white women than in non-Hispanic Black women, after adjusting for sunscreen use. 47
Other Hispanic women who saw themselves as overweight had urine oxybenzone 69 percent higher than non-Hispanic Black women, against 32 percent higher among those who saw their weight as right. 47
In a national survey of 1,082 Swedish adolescents aged 11 to 21 in 2016-2017, mean urine oxybenzone was more than 15 times lower than in the US national survey. 112
In BALB/c mice carrying Trp53-null mammary transplants, oxybenzone at 70 mg/kg body weight a day protected against epithelial tumors on a lifelong low-fat diet but promoted them on a high-fat diet in adulthood. 61
Rats fed oxybenzone at 50,000 ppm in their diet for 13 weeks had markedly lower epididymal sperm density and longer estrous cycles. 14
In mice given oxybenzone on the skin for 13 weeks, epididymal sperm density fell at all three doses evaluated, 22.75, 91 and 200 mg/kg. 14
Rats given 12.5 to 200 mg/kg of oxybenzone on the skin for 13 weeks showed no effect of it except higher kidney weights in females. 14
Among 282 girls followed from age 6 or 7, those in the second quarter of urine oxybenzone began breast development earlier than those in the lowest quarter, a hazard ratio of 1.584, which the authors say may be a random effect. 56
A skin model trained on laboratory and FDA trial data predicted that, of seven sunscreen filters applied to the face, oxybenzone would reach the highest blood concentration. 38
Among 8,498 US adults in the 2005-2014 national surveys, people at the 75th percentile of urine oxybenzone had lower odds of diabetes than those at the 25th, an odds ratio of 0.69; the authors could not rule out reverse causation. 113
In 8,027 US adults in national survey data from 2005 to 2016, those in the top quarter of urine oxybenzone had lower odds of diabetes than those in the bottom quarter, an odds ratio of 0.63, with the curve flattening above about 6.8 ng/mL. 114
Across 1,339 teenagers pooled from six European biomonitoring studies, each natural-log unit rise in urine oxybenzone went with higher odds of obesity, an odds ratio of 1.20, and 1.34 in boys. 115
In urine from Chinese children, the geometric mean share of oxybenzone in its free, unconjugated form was 0.64, twenty times the 0.03 found in US children. 78
Among 90 Californian adult and child pairs, those who had used sunscreen in the past 24 hours had urine oxybenzone 2.21 times as high in adults and 3.10 times as high in children. 43
In the SUPERB families, adult shaving cream users also had urine oxybenzone 1.85 times as high as non-users. 43
Oxybenzone in the SUPERB adults ran about 9 times higher than in US adults generally over the same period, while other phenols were similar. 43
In the authors' intake estimate from 231 products, skin lotions and face creams supplied more than 80 percent of daily oxybenzone exposure from personal care products. 6
A 1989 report described 4 patients whose photoallergy to oxybenzone in sunscreens was mistaken for, or worsened, their light sensitivity. 23
In the 1978 FDA panel's absorption test, 96.51 percent of the oxybenzone in a lotion spread on the forearms of 14 people for four hours was recovered from the skin. 13
Under a solar simulator, a lotion with 3 percent oxybenzone raised the dose of light needed to redden skin by a factor of 2.37, against 1.31 for the lotion alone and 7.06 for 4 percent padimate O. 13
In the 2020 FDA trial, all 24 people who applied an oxybenzone product indoors had more than 0.5 ng/mL in their blood within 2 hours of a single application. 4
In the same trial, oxybenzone's terminal half-life in the blood was 78.5 hours with the lotion and 79.2 hours with the aerosol spray. 4
In the 2020 FDA trial, the oxybenzone lotion gave a peak blood level of 258.1 ng/mL, against 7.1 ng/mL for avobenzone in the same lotion. 4
Of 23,908 North American patients patch tested from 2001 to 2010, 82 (0.34 percent) reacted to oxybenzone. 2
Boys aged 12 to 19 in the top quarter of urine oxybenzone in the 2011-2012 national survey had 36.87 percent lower serum testosterone than boys in the bottom quarter, with a 95 percent confidence interval from 1.98 to 59.34 percent lower. 8
In 22 mother and cord blood pairs collected at delivery in Tianjin, oxybenzone was detected in 12 cord blood samples and 7 maternal samples, and the cord-to-mother ratio averaged 0.48 where both were measured. 52
Pooling ten studies of mothers' urine oxybenzone and birth size, a 2020 meta-analysis found no association with birth weight, length, or head circumference. 51
In a two-year feeding study, malignant meningiomas appeared in 0, 1, 3, and 0 of 50 male rats fed 0, 1,000, 3,000, and 10,000 ppm oxybenzone. 15
In the same two-year study, thyroid C-cell adenomas appeared in 5, 11, 17, and 10 of 50 female rats across the same feed concentrations. 15
The EU's safety committee calculated a margin of safety of 38 for a 6 percent oxybenzone body cream, assuming 18 grams applied a day, 9.9 percent absorbed through the skin, and a 60 kilogram body. 17