Phthalates are quasi-ubiquitous plasticizers found in products including building materials, food packaging, clothes, and personal care products. Thus, we are permanently exposed to them. Phthalates are endocrine disruptors that can be ingested or absorbed through the skin. Because DEHP is the most common phthalate, we sought to investigate its effect on the epidermis. We generated human epidermal equivalents (HEEs) with keratinocytes from healthy donors and treated them topically with DEHP. Corneodesmosin was decreased in the uppermost layers of the epidermis, indicating a defect in epidermal barrier formation. Furthermore, biotin-diffusion assay showed defective tight junctions. Moreover, the expression of IL1A, IL1B, IL6, IL8 and IL18 was up-regulated, indicating a pro-inflammatory effect of DEHP. Interestingly, GLUT1 was increased as well as glucose consumption, suggesting the capacity of DEHP to modulate metabolic pathways. Furthermore, LC-MS analysis on hair showed that plasticizers, especially phthalates, are increased in AD patients. Phthalates were detectable in about 50% of AD patients and controls; however, semi-quantitative analysis indicated higher levels of phthalates, particularly DEHP, in AD patients. Interestingly, LC-MS analysis of skin samples further showed that 3.7% of all industrial compounds found on the skin were phthalates in the control group, whereas it reached 15.4% in AD patients. Thus, these data show that AD patients are more exposed to topical phthalates that they can accumulate, probably due to damaged epidermal barrier. In vitro experiment showed that DEHP leads to inflammation and epidermal barrier damage, hence suggesting that chronic skin exposure to phthalates might contribute to AD development or flare-ups.

ESDR214 - Topical DEHP exposure leads to inflammation and epidermal barrier damage in epidermal equivalents

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.