Rechecked: the chemicals in sunscreens penetrate the blood

In 2019, the FDA food and drug administration (FDA) has published a study according to which the chemicals contained in sunscreens, penetrate into the human body in potentially harmful doses.

“Conduct.Science” in detail told about this work. Recall that in the course of the study in the blood plasma of volunteers after one day of use of sunscreens (lotion, cream and two kinds of spray) was exceeded by concentrations of four key substances: avobenzone, oxybenzone, octocrylene and Mexoryl (or ecamsule).

Concentrations were below 0.5 nanograms per milliliter. This is the threshold set by the FDA for a waiver of additional safety testing.

Experts, however, were not convinced that these concentrations of these substances are associated with risks to human health.

in addition, the study was criticized for small sample size (it was attended by only 24 people).

So specialists the FDA held another job. They expanded the sample size and the list of substances the concentration of which was studied in the blood of people.

In the new test involved 48 healthy men and women. Their average age was 38 years.

Volunteers randomly “appointed” one of the four sun-protection sprays or lotions. The participants were covered up to 75% of the body once on the first day of the experiment and four times a day for the next three days.

each volunteer within 21 days of observations were taken in a total of 34 blood samples.

the Tests showed that the majority of participants of the active ingredients is absorbed at levels exceeding the FDA threshold, even after a single application.

this, in particular, consists of six substances: avobenzone, oxybenzone, octocrylene, homosalate, octisalate and octinoxate.

the Maximum concentration of oxybenzone was 180,1 258,1 to nanograms per milliliter, and the concentrations of five other airin ranged from 3.3 to 23.1 nanograms per milliliter, depending on the varieties of sunscreen.

While the active ingredients of sunscreens is often delayed in the body: more than 50% of the volunteers levels of avobenzone, octisalate and octinoxate remained elevated for seven days, while the concentration of homosalate and oxybenzone remained above the threshold for three weeks.

the Most common undesirable side effect was rash, she appeared in 14 of the participants.

Thus, specialists have confirmed and extended the results of previous work.

However, the question is, what danger can bear the ingredients of sunscreens remains open.

According to the FDA and oncologists, there has been no proof that the identified substances cause harm. (Although under suspicion by the Russian researchers is avobenzone: experiments have shown that chlorinated water under the action of sunlight it breaks down into harmful chemicals.)

meanwhile, in the dangers of ultraviolet radiation no doubt, his impact could lead not only to sunburn and accelerated skin aging, but also the very real cancer.

of Course, the new findings are of concern and talk about the need for additional research.

By the way, about the limitations of the new work. The present test was conducted in laboratory conditions, and it is unknown how exposure to heat and sunlight in the open air would affect the absorption of active ingredients of sunscreens skin people.

At this stage, the experts urge the public to continue to use sunscreen when necessary.

Toxicologist from the University of Hertfordshire Robert Chilcott (Robert Chilcott) noted that the results of the study FDA several to be expected because the skin is not a barrier and can absorb the chemicals from the funds deposited on its toplastnosti.

“It doesn’t mean that sunscreen is unsafe to use. But manufacturers should undertake appropriate tests of security, — said Professor Chilcott not taking part in the new work. — It should be emphasized that the health benefits of using sunscreen are well known and greatly outweighs the risks associated with excessive sun exposure on unprotected skin”.

Recall that the sunscreen people have to recommend a dermatologist. The authors of an accompanying editorial stress that the experts drafting such recommendations must be mindful of the balance of risks and benefits for each individual.

in Other words, clinicians must determine whether the benefits exceed the risks for a particular patient. This balance may be different depending on factors such as skin type and age, the frequency and duration of use.

read More about the new study described in an article presented in the journal JAMA.

by the Way, earlier “Conduct.Science” ( wrote about a new sunscreen based on DNA and natural remedy from ultraviolet radiation from the slime of the fish and shrimp shells. We were also told how to tan without sun tanning and skin cancer.

Text: To.Science