The effects of UV filters on health and the environment

Organic ultraviolet filters (OUVF) in freshwater bathing areas: Necessary sunscreen protection versus environmental threat

This study presents the first comprehensive assessment of seven organic ultraviolet filters (OUVFs), namely benzophenone-3 (BP3), 4-methylbenzylidene camphor (4MBC), octocrylene (OC), ethylhexyl methoxycinnamate (EHMC), isoamyl p-methoxycinnamate (IAMC), butyl methoxydibenzoylmethane (BMDBM), and homosalate (HMS), in Polish freshwater ecosystems, providing novel insights into their seasonal variability and ecological risks. Water samples from three recreational lakes and a reference reservoir were collected in April and July from both surface and water column layers were analysed to quantify OUVFs concentrations and calculate aquatic risk quotients (RQs). Our results revealed a clear seasonal pattern, with significantly higher OUVF concentrations in July, particularly at Kryspinów reservoir, coinciding with peak tourist activity. IAMC, HMS, and BMDBM were the main contributors to moderate cumulative risk values with localized high-risk values at Kryspinów, while the reference site exhibited consistently low contamination and negligible risks. This study not only establishes a baseline for OUVF contamination in Central European recreational waters but also demonstrates the utility of a multi-depth sampling approach in assessing pollution dynamics. The findings contribute to the growing understanding of emerging contaminants in freshwater ecosystems and underline the need for enhanced environmental monitoring and regulatory measures.

Effects of the UV Filter Octocrylene and Its Degradation Product Benzophenone on Pacific Oyster (Magallana gigas) Larvae: A Call for Reassessment of Environmental Hazards

Early life stages are pivotal to the functioning and resilience of ecological systems, displaying heightened vulnerability to environmental changes and exposure to contaminants. Octocrylene (OC), an organic ultraviolet (UV) filter, and its breakdown product benzophenone (BP) are commonly found in aquatic environments, but their impact on keystone processes determining the success or failure of the early life stages of marine organisms remains underexplored. This study aims to assess the impacts of OC and BP at environmentally realistic concentrations (1, 10, and 100 µg.L-1), over a 24 h exposure period, on larvae of the Pacific oyster (Magallana gigas). A multiparametric approach was employed, examining DNA integrity, embryo-larval development and swimming velocity. The results showed that DNA integrity and swimming velocity were not affected by OC or BP; however, both compounds increased developmental abnormalities in D-shaped larvae in all concentrations tested. Considering the robustness of morphological parameters, often assumed as irreversible, and their critical influence on larvae survival, these findings suggest that environmentally relevant concentrations of OC and BP may threaten the success of oyster larvae, potentially impacting the population's long-term stability and, ultimately, raising ecological health issues.

A review of ultraviolet filters and their impact on aquatic environments

Numerous anthropogenic ultraviolet filters (UVF) have been detected in aquatic environments and concerns have arisen regarding their potential impacts on aquatic organisms. This manuscript reviews the environmental concentrations and potential toxicity of various UVF. The highest concentrations of UVF are typically observed near frequently visited recreational areas and during peak water-activity periods, which suggests that sunscreen application correlates with noticeable alterations in UVF concentrations. Aquatic concentrations of certain filters have sporadically exceeded 10 μg/L, although most measurements remain below 1 µg/L, which is below commonly reported toxicity levels. UVF have also been detected in aquatic organisms, typically ranging from nondetectable levels to a few hundred ng/g, depending on the species. The toxic effects from UVF, such as coral bleaching and diminished growth, have been observed in laboratory settings, however, toxicity tends to manifest only at significantly higher levels than what is typically detected in aquatic environments. Further research is imperative to provide consumers with improved guidance on selecting sunscreen containing UVF that poses the least environmental risk.

In vitro study of the UV-filter homosalate effects on rat and human thyroid cells

Homosalate is a UV-B filter, commonly used in sunscreens and personal-care products. Homosalate was shown to exert estrogenic and anti-androgenic effects in animal models, while few data are available on the effects of Homosalate on thyroid cells. The aim of this study was to evaluate if Homosalate exposure could exert adverse effect on thyroid cells in vitro. FRTL-5 and NHT were treated with increasing concentration of Homosalate for 24-48-72 h. Cell viability was assessed by WST-1. Cell proliferation was evaluated by cristal violet. Micronucleus staining was performed to assess genotoxicity. mRNA levels of thyroid-related genes (TSHR, TPO, TG, NIS, and PAX8) were evaluated by RT-PCR. Changes in ROS production by FRTL-5 and NHT were assessed with H2DCFDA. Homosalate significantly reduced cell viability after 72 h in FRTL-5 starting from the concentration 250 μM, while in NHT, Homosalate exposure significantly reduced cell viability after 48 and 72 h only at highest concentration (2000 μM). Cell proliferation was not modified by Homosalate at any concentration and time-point. Homosalate significantly up-regulated mRNA expression levels of TPO and Tg genes in FRTL-5, while a significant increase only in Tg mRNA expression was observed in NHT. No changes in ROS production was found in both cell types. The present study suggest that the effects of Homosalate exposure may differ according to the type of cell tested. The in vitro exposure of thyroid cells to Homosalate produces: i) cytotoxicity at high concentrations or after long time of incubation, ii) genotoxicity only in rat thyroid cells at the highest concentration, iii) upregulation of Tg mRNA in both thyroid cell types and of TPO mRNA in rat thyroid cells, iv) no changes in cell proliferation or oxidative stress. Further studies on the effects of Homosalate on thyroid cells should be encouraged.

Ethylhexyl triazone sunscreen and its disinfection byproducts obtained after chlorine treatment: Ecofriendliness or ecotoxicity?

In recent years, there has been a growing demand for high-quality sunscreens that combine high efficacy with ecological characteristics. This trend has led to an increased use of triazine compounds, which represent an emerging class of UV filters. While it is well-established that sunscreens can have significant environmental impacts, there is limited data on the degradation of triazine UV filters, despite available information on their environmental persistence, particularly in relation to disinfection processes. This study investigates the chemical fate of ethylhexyl triazone (EHT) under chlorination conditions, typical of swimming pools. Twelve disinfection byproducts (DBPs) were isolated and fully identified using nuclear magnetic resonance and mass spectrometry, with three of these byproducts being identified for the first time. DBP1-DBP12 were isolated at relative percentages of 1.26, 9.68, 1.05, 0.42, 0.84, 3.37, 3.58, 1.89, 0.84, 1.47, 0.42, and 0.63. Additionally, a mechanism for their formation was proposed. The ecotoxicological assessment of EHT and of byproducts (DBP1-DBP4) was conducted using acute, sub-chronic or chronic toxicity tests in producers and primary consumers of the freshwater trophic chain. The organisms included the alga Raphidocelis subcapitata, the rotifer Brachionus calyciflorus, the crustacean anostracan Thamnocephalus platyurus and the benthic ostracod Heterocypris incongruens. EHT caused a lethal median concentration in rotifers, with values in the range of tens of mg/L. EHT, DBP1, and DBP4 exhibited sub-chronic effects in ostracods at concentrations in the μg/L range, with EC50s of 210, 9, 20 μg/L, respectively. Rotifers were slightly affected by DBP3 with a chronic EC50 of 200 μg/L. Algae were not affected by either EHT or byproducts.

The structural characterization and UV-protective properties of an exopolysaccharide from a Paenibacillus isolate

Introduction

Overexposure to ultraviolet (UV) light is known to cause damage to the skin, leading to sunburn and photo-aging. Chemical sunscreen products may give rise to health risks including phototoxicity, photosensitivity, and photosensitivity. Natural polysaccharides have attracted considerable interests due to diverse biological activities.

Methods

A novel polysaccharide isolated was purified and structurally characterized using chemical methods followed by HPLC, GLC-MS, as well as 1D and 2D NMR spectroscopy. The photoprotective effect of the EPS on UVB-induced damage was assessed in vitro using cultured keratinocytes and in vivo using C57BL/6 mouse models.

Results

The average molecular weight of the EPS was 5.48 × 106 Da, composed of glucose, mannose and galactose residues at a ratio of 2:2:1. The repeating units of the EPS were →3)-β-D-Glcp (1→3) [β-D-Galp (1→2)-α-D-Glcp (1→2)]-α-D-Manp (1→3)-α-D-Manp (1→. In cultured keratinocytes, the EPS reduced cytotoxicity and excessive ROS production induced by UVB irradiation. The EPS also exhibits an inhibitory effect on oxidative stress, inflammation, and collagen degradation found in the photodamage in mice. 1H NMR-based metabolomics analysis for skin suggested that the EPS partly reversed the shifts of metabolic profiles of the skin in UVB-exposed mice.

Conclusion

The EPS exhibits skin photoprotective effects through regulating oxidative stress both in vivo and in vitro. Our findings highlight that the EPS is a potential candidate in sunscreen formulations for an efficient solution to UVB radiation.

Looking beyond the obvious: The ecotoxicological impact of the leachate from fishing nets and cables in the marine mussel Mytilus galloprovincialis

Once in the marine environment, fishing nets and cables undergo weathering, breaking down into micro and nano-size particles and leaching plastic additives, which negatively affect marine biota. This study aims to unravel the ecotoxicological impact of different concentrations of leachate obtained from abandoned or lost fishing nets and cables in the mussel Mytilus galloprovincialis under long-term exposure (28 days). Biochemical biomarkers linked to antioxidant defense system, xenobiotic biotransformation, oxidative damage, genotoxicity, and neurotoxicity were evaluated in different mussel tissues. The chemical nature of the fishing nets and cables and the chemical composition of the leachate were assessed and metals, plasticizers, UV stabilizers, flame retardants, antioxidants, dyes, flavoring agents, preservatives, intermediates and photo initiators were detected. The leachate severely affected the antioxidant and biotransformation systems in mussels' tissues. Following exposure to 1 mg·L-1 of leachate, mussels' defense system was enhanced to prevent oxidative damage. In contrast, in mussels exposed to 10 and 100 mg·L-1 of leachate, defenses failed to overcome pro-oxidant molecules, resulting in genotoxicity and oxidative damage. Principal component analysis (PCA) and Weight of Evidence (WOE) evaluation confirmed that mussels were significantly affected by the leachate being the hazard of the leachate concentrations of 10 mg·L-1 ranked as major, while 1 and 100 mg·L-1 was moderate. These results highlighted that the leachate from fishing nets and cables can be a threat to the heath of the mussel M. galloprovincialis.

Ultraviolet Filters: Dissecting Current Facts and Myths

Skin cancer is a global and increasingly prevalent issue, causing significant individual and economic damage. UV filters in sunscreens play a major role in mitigating the risks that solar ultraviolet ra-diation poses to the human organism. While empirically effective, multiple adverse effects of these compounds are discussed in the media and in scientific research. UV filters are blamed for the dis-ruption of endocrine processes and vitamin D synthesis, damaging effects on the environment, induction of acne and neurotoxic and carcinogenic effects. Some of these allegations are based on scientific facts while others are simply arbitrary. This is especially dangerous considering the risks of exposing unprotected skin to the sun. In summary, UV filters approved by the respective governing bodies are safe for human use and their proven skin cancer-preventing properties make them in-dispensable for sensible sun protection habits. Nonetheless, compounds like octocrylene and ben-zophenone-3 that are linked to the harming of marine ecosystems could be omitted from skin care regimens in favor of the myriad of non-toxic UV filters.

Protective Effects of Pear Extract on Skin from In Vitro and In Vivo UVA-Induced Damage

The ancient Chinese medical book "Compendium of Materia Medica" records that pears can relieve symptoms of respiratory-related diseases. Previous research has shown that pear Pyrus Pyrifolia (Burm.f.) Nakai has antioxidant and anti-inflammatory properties. However, the anti-inflammatory, antioxidant, and anti-photoaging protective effects of Pyrus pyrifolia (Burm.f.) Nakai seed components have not been studied. Ultraviolet light (UV) causes skin inflammation, damages the skin barrier, and is an important cause of skin photoaging. Therefore, UV light with a wavelength of 365 nm was used to irradiate HaCaT and mice. Western blot, real-time quantitative polymerase chain reaction, and fluorescence imaging system were used to explore its anti-UVA mechanism. Dialysis membrane and nuclear magnetic resonance were used for the chemical constituent analysis of pear seed water extract (PSWE). We found that PSWE can significantly reduce UVA-induced skin cell death and mitogen-activated protein kinase phosphorylation and can inhibit the mRNA expression of UVA-induced cytokines (including IL-1β, IL-6, and TNF-α). In addition, PSWE can also reduce the generation of oxidative stress within skin cells. In vivo experimental studies found that PSWE pretreatment effectively reduced transepidermal water loss, inflammation, redness, and dryness in hairless mice. The molecular weight of the active part of pear water extract is approximately 384. Based on the above results, we first found that pear seeds can effectively inhibit oxidative stress and damage caused by UVA. It is a natural extract with antioxidant properties and anti-aging activity that protects skin cells and strengthens the skin barrier.

The use of natural extracts with photoprotective activity: a 2015-2023 patent prospection

Synthetic sunscreen offers protection against excessive exposure to ultraviolet (UV) radiation from the sun, and protects the skin from possible damage. However, they have low efficacy against the formation of reactive oxygen species (ROS), which are highly reactive molecules that can be generated in the skin when it is exposed to UV radiation, and are known to play a role in oxidative stress, which can contribute to skin aging and damage. Thus, there is an ongoing search for sunscreens that do not have these negative effects. One promising source for these is natural products. Therefore, the current patent review summarizes topical formulations made from natural compounds that have antioxidant properties and can be used as photoprotective or anti-aging agents, either using a single natural extract or a combination of extracts. The review reports basic patent information (applicant country, type of applicant, and year of filing) and gives details about the invention, including its chemical composition, and the in vitro and in vivo tests performed. These patents describe natural products that can be used to protect the skin and validate their efficacy, and safety, in addition to standardizing their formulations. The compositions described illustrate the consistent innovation in the use of natural products to protect against UV damage and photoaging disorders, a promising field which is receiving growing global recognition.