Americans have plenty of sunscreen options, technically speaking. The aisles of any given pharmacy are typically filled with dozens of brightly colored bottles that claim to offer broad-spectrum protection as well as SPFs upward of 50. But lately, American sunscreen has come under fire with critics arguing that sunscreen in the U.S. could be a whole lot better. Media from Vox to Bloomberg to Business Insider have decried American options as being thicker, greasier, goopier, less pleasant to apply, and perhaps most importantly, less safe than their European counterparts.

In February, the U.S. Food and Drug Administration (FDA) announced that it planned to take steps to make sunscreens safer and more effective. As part of that, the FDA says it is currently reviewing the 16 approved ingredients on the market — including zinc oxide, oxybenzone, avobenzone, and others — to determine whether they’re really safe for Americans to use. But the problem isn’t only that currently available ingredients could be more effective, but also that U.S. consumers have far fewer options to choose from compared to buyers in other countries.

“Some of the ingredients used in Europe give better coverage over the full-spectrum of UVA light, which is not fully covered by the products in the United States.”

The two types of ultraviolet (UV) rays that can contribute to skin problems are UVA and UVB. The difference is that UVB rays reach the top layer of skin and cause sunburns, while UVA rays are longer in wavelength and penetrate more deeply into skin. These rays play a role in skin aging.

There are a number of safe sunscreen products currently on the market in the U.S. Where Europeans might have Americans beat is UVA protection, says Dr. Joshua Zeichner, a New York-based dermatologist. “Some of the ingredients used in Europe give better coverage over the full-spectrum of UVA light, which is not fully covered by the products we are using in the United States,” he says. A 2017 study published in the Journal of the American Academy of Dermatology supports the claim, finding that of 20 different U.S. sunscreens tested, almost half did not meet European standards for UVA protection, though most met the U.S. standards for it.

Experts long believed that UVB rays alone were responsible for skin cancer, while exposure to UVA rays only led to wrinkles and sunspots. “We’ve been so focused on SPF in the United States, but as we’ve learned more and more about UV rays, we’ve realized that UVA rays can cause mutations that lead to skin cancer, immunosuppression, and premature skin aging,” says Dr. Elizabeth Hale, a clinical associate professor of dermatology at NYU Langone Center.

According to the American Cancer Society, skin cancer is the most common cancer in the U.S., and melanoma rates have been rising steadily for the past three decades. Preventing skin cancer with sunscreen is where things get complicated. Because ingredients in sunscreens claim to reduce the risk of sunburn and skin cancer, the FDA treats sunscreens as over-the-counter drugs, meaning the requirements to meet FDA standards are much more stringent than they are for cosmetics. “The FDA requires topical safety studies that look at skin irritation, sensitivity, and safety when exposed to the sun,” says Dr. Susan Massick, a dermatologist at The Ohio State Wexner Medical Center. “They recently proposed adding additional safety studies regarding things like systemic absorption, efficacy, and potential for developmental and reproductive toxicity studies.”

The FDA is still reviewing the 16 ingredients available in the U.S. but so far, only two — zinc oxide and titanium dioxide — have been designated as “generally recognized as safe and effective” or GRASE. Another two — PABA and trolamine salicylate — are “not GRASE for use in sunscreens due to safety issues,” the agency recently wrote. The FDA also determined there wasn’t enough data to determine whether the remaining 12 ingredients should receive GRASE status, and that the agency is asking companies to submit studies and data that support the ingredients’ safety.

In contrast, the European Union regulates sunscreens as cosmetics, and there are at least 27 different approved sunscreen ingredients, many of which offer a better degree of protection against UVA rays. Some of these ingredients have cult followings among U.S. customers looking for better offerings.

One of those ingredients is ecamsule, trade name Mexoryl, which has been widely used in European sunscreens since 1993. (Mexoryl is used in Canada under the trade name Mexoryl SX). Mexoryl is also considered a stable ingredient, meaning that it degrades slowly when exposed to sunlight and doesn’t need to be applied as often as other ingredients. It’s a favorite of beauty bloggers and the subject of many Reddit /skincare addiction threads. Technically, it’s possible to find in the U.S., but it’s very limited and costly.

The French arm of L’Oreal, La Roche-Posay, patented encamsule in 1982, Dr. Massick says, but the company wasn’t able to obtain FDA approval for use in the U.S. until 2006 — and even then, it was limited to one specific sunscreen. You can find it online and in some stores in the U.S. under the name Anthelios, though it’ll run you at least $30 a bottle.

For L’Oreal to expand its use of Mexoryl in the U.S., it would need to apply for additional FDA approval. That means not just doing more research, which can be a long process, but also paying for it — which can be expensive. It’s unclear whether L’Oreal will choose to do so. (Elemental reached out to L’Oreal for comment but the company did not respond).

“We know that there’s one part of the UVA spectrum — ‘short’ UVA rays — that U.S. sunscreens don’t block well against, and we know that European ingredients, like Mexoryl, do block those more effectively,” says Hale.

Most Americans do not regularly use sunscreen. And yet, the sunscreens available are not as effective as they could be.

It is worth noting, however, that the FDA recently released the results of a small sunscreen study, which included one product with a 2% concentration of Mexoryl. The study found that of 167 blood samples taken from six people, 58 samples had traces of Mexoryl in them (the remaining 109 samples had levels so low as to be undetectable). The findings implied that some sunscreen ingredients, Mexoryl included, can make it into the bloodstream.

Massick cautions that, “absorption does not automatically equal harmful,” but a growing number of people may worry about the potential health and environmental effects. Take oxybenzone: Like Mexoryl, oxybenzone is a chemical filter, meaning it creates a chemical reaction that absorbs UV rays (in contrast, physical blockers such as zinc oxide sit on your skin and form a physical barrier to deflect UV rays). Oxybenzone has been used in American sunscreen for decades. However, it’s also been found in breast milk, urine, and amniotic fluid, and some animal studies have suggested that it might have hormone-disrupting effects. Recently the ingredient came under fire for its potential role in accelerating coral bleaching, which is partly why Hawaii moved to ban sunscreens with oxybenzone last summer. It’s also one of the ingredients found to seep into the bloodstream easily in the FDA’s new study.

Studies show that most Americans do not regularly use sunscreen. And yet, the sunscreens available are not as effective as they could be or, according to federal officials, are not the safest for people or the environment. Until those issues are addressed, consumer groups recommend looking for sunscreens that offer both UVA and UVB protection and have ingredients that are considered safe: zinc oxide and titanium dioxide.

“As a dermatologist who specializes in skin cancer and skin aging,” says Hale, “We’re constantly on a quest for our patients to find a sunscreen they actually will use and look forward to using instead of dreading the process.”