Dermal uptake of petroleum substances

Sexual dimorphism association of combined exposure to volatile organic compounds (VOC) with kidney damage

BACKGROUND

Epidemiological evidence emphasizes air pollutants' role in chronic kidney disease (CKD). Volatile organic compounds (VOCs) contribute to air pollution, yet research on VOCs and kidney damage, especially gender disparities, is limited.

METHODS

This study analyzed NHANES data to explore associations between urinary VOC metabolite mixtures (VOCMs) and key kidney-related parameters: estimated glomerular filtration rate (eGFR), albumin-to-creatinine ratio (ACR), chronic kidney disease (CKD), and albuminuria. Mediation analyses assessed the potential mediating roles of biological aging (BA) and serum albumin in VOCM mixtures' effects on kidney damage. Sensitivity analyses were also conducted.

RESULTS

The mixture analysis unveiled a noteworthy positive association between VOCM mixtures and the risk of developing CKD, coupled with a significant negative correlation with eGFR within the overall participant cohort. These findings remained consistent when examining the female subgroup. However, among male participants, no significant link emerged between VOCM mixtures and CKD or eGFR. Furthermore, in both the overall and female participant groups, there was an absence of a significant correlation between VOCM mixtures and either ACR or albuminuria. On the other hand, in male participants, while no significant correlation was detected with albuminuria, a significant positive correlation was observed with ACR. Pollutant analysis identified potential links between kidney damage and 1,3-butadiene, toluene, ethylbenzene, styrene, xylene, acrolein, crotonaldehyde and propylene oxide. Mediation analyses suggested that BA might partially mediate the relationship between VOCM mixtures and kidney damage.

CONCLUSION

The current findings highlight the widespread exposure to VOCs among the general U.S. adult population and indicate a potential correlation between exposure to VOC mixtures and compromised renal function parameters, with notable gender disparities. Females appear to exhibit greater sensitivity to impaired renal function resulting from VOCs exposure. Anti-aging treatments may offer some mitigation against kidney damage due to VOCs exposure.

HIF-1α/m6A/NF-κB/CCL3 axis-mediated immunosurveillance participates in low level benzene-related erythrohematopoietic development toxicity

Defective erythropoiesis is one of the causes of anemia and leukemia. However, the mechanisms underlying defective erythropoiesis under a low-dose environment of benzene are poorly understood. In the present study, multiple omics (transcriptomics and metabolomics) and methods from epidemiology to experimental biology (e.g., benzene-induced (WT and HIF-1α + ) mouse, hiPSC-derived HSPCs) were used. Here, we showed that erythropoiesis is more easily impacted than other blood cells, and the process is reversible, which involves HIF-1 and NF-kB signaling pathways in low-level benzene exposure workers. Decreased HIF-1α expression in benzene-induced mouse bone marrow resulted in DNA damage, senescence, and apoptosis in BMCs and HSCs, causing disturbances in iron homeostasis and erythropoiesis. We further revealed that HIF-1α mediates CCL3/macrophage-related immunosurveillance against benzene-induced senescent and damaged cells and contributes to iron homeostasis. Mechanistically, we showed that m6A modification is essential in this process. Benzene-induced depletion of m6A promotes the mRNA stability of gene NFKBIA and regulates the NF-κB/CCL3 pathway, which is regulated by HIF-1α/METTL3/YTHDF2. Overall, our results identified an unidentified role for HIF-1α, m6A, and the NF-kB signaling machinery in erythroid progenitor cells, suggesting that HIF-1α/METTL3/YTHDF2-m6A/NF-κB/CCL3 axis may be a potential prevention and therapeutic target for chronic exposure of humans to benzene-associated anemia and leukemia.

How to Promote Skin Repair? In-Depth Look at Pharmaceutical and Cosmetic Strategies

Skin repair encompasses epidermal barrier repair and wound healing which involves multiple cellular and molecular stages. Therefore, many skin repair strategies have been proposed. In order to characterize the usage frequency of skin repair ingredients in cosmetics, medicines, and medical devices, commercialized in Portuguese pharmacies and parapharmacies, a comprehensive analysis of the products' composition was performed. A total of 120 cosmetic products, collected from national pharmacies online platforms, 21 topical medicines, and 46 medical devices, collected from INFARMED database, were included in the study, revealing the top 10 most used skin repair ingredients in these categories. A critical review regarding the effectiveness of the top ingredients was performed and an in-depth analysis focused on the top three skin repair ingredients pursued. Results demonstrated that top three most used cosmetic ingredients were metal salts and oxides (78.3%), vitamin E and its derivatives (54.2%), and Centella asiatica (L.) Urb. extract and actives (35.8%). Regarding medicines, metal salts and oxides were also the most used (47.4%) followed by vitamin B5 and derivatives (23.8%), and vitamin A and derivatives (26.3%). Silicones and derivatives were the most common skin repair ingredients in medical devices (33%), followed by petrolatum and derivatives (22%) and alginate (15%). This work provides an overview of the most used skin repair ingredients, highlighting their different mechanisms of action, aiming to provide an up-to-date tool to support health professionals' decisions.

Human biomonitoring of low-level benzene exposures

Historically, benzene has been widely used in a large variety of applications. Occupational exposure limits (OELs) were set for benzene as it was found to be acutely toxic, causing central nervous system depression at high exposures. OELs were lowered when it was discovered that chronic exposure to benzene could cause haematotoxicity. After confirmation that benzene is a human carcinogen causing acute myeloid leukaemia and possibly other blood malignancies, OEL were further lowered. The industrial application of benzene as solvent is almost completely discontinued but it is still used as feedstock for the production of other materials, such as styrene. Occupational exposure to benzene may also occur since it is present in crude oil, natural gas condensate and a variety of petroleum products and because benzene can be formed in combustion of organic material. In the past few years, lower OELs for benzene in the range of 0.05-0.25 ppm have been proposed or were already established to protect workers from benzene-induced cancer. The skin is an important potential route of exposure and relatively more important at lower OELs. Consequently, human biomonitoring - which integrates all exposure routes - is routinely applied to control overall exposure to benzene. Several potential biomarkers have been proposed and investigated. For compliance check of the current low OELs, urinary S-phenylmercapturic acid (S-PMA), urinary benzene and blood benzene are feasible biomarkers. S-PMA appears to be the most promising biomarker but proper validation of biomarker levels corresponding to airborne benzene concentrations below 0.25 ppm are needed.

Kill two birds with one stone: Ceramisite production using organic contaminated soil

Disposal of organic-contaminated soil through ceramsite production can not only generate ceramsite with acceptable properties but also completely remediate the organic-contaminated soil owing to high treatment temperature. However, the removal mechanism of organic pollutants and the gas-solid phase distribution of the pollutants remain unclear. In this study, coking contaminated soils with high concentrations of polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbon (PHC) were used to prepare ceramsite at 1160 °C. The quality of ceramsite met the required product standard when the disposal ratio of contaminated soil was up to 60%. The concentration of PAHs and PHC in the soil was 57.7 mg kg^-1 and 255 mg kg^-1. After the experiment, almost no PAHs and PHC were found in the ceramsite. High-ring PAHs were dominant in the flue gas when using model soil spiked with PAHs. Computed tomography scanning indicated that cracks developed in the ceramsite when the temperature was higher than 200 °C. High-temperature in-situ thermal analysis showed that when the temperature was increased to 400 °C, the pollutant from the interior of ceramsite would flow into the flue gas with the released volatile matter. Thermal desorption and degradation of PAHs were the main mechanisms of pollutant removal.

Development and Evaluation of Biocompatible Topical Petrolatum-liquid Crystal Formulations with Enhanced Skin Permeation Properties

Transdermal administration represents a major advancement over traditional pharmaceutical dosing methods. However, a frequent issue is inadequate penetration of the active medicinal component through the skin. As a result, in the current research, we assessed the utility of newly developed petrolatum-liquid crystal (LC) ointment formulations and characterized their biocompatibility and function in the transdermal drug delivery system. To begin, we made petrolatum-LC formulations using p-aminobenzoic acid (PABA) as a hydrophilic model molecule. The viscosity, small-angle X-ray scattering (SAXS), particle diameters, and z-potential were measured to assess the physicochemical properties of the formulations. A dialysis release technique was used to evaluate medication release from petrolatum-LC formulations. In vitro testing was performed to determine the potential to enhance skin penetration. The biocompatibility of the produced formulations was further tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and single-cell gel electrophoresis. According to the results, the novel petrolatum-LC formulations are biocompatible and effective in forming hexosomes. PABA skin penetration was significantly enhanced by the new petrolatum-LC formulations. According to this study, petroleum-LC formulations are more efficient than commercial petrolatum in terms of skin permeability improvement and PABA skin concentration.

In silico predictions of absorption of MDI substances after dermal or inhalation exposures to support a category based read-across assessment

Methylenediphenyl diisocyanate (MDI) substances used polyurethane production can range from their simplest monomeric forms (e.g., 4,4'-MDI) to mixtures of the monomers with various homologues, homopolymer, and prepolymer derivatives. The relative dermal or inhalation absorption of 39 constituents of these substances in human were predicted using the GastroPlus® program. Predicted dermal uptake and absorption of the three MDI monomers from an acetone vehicle was 84-86% and 1.4-1.5%, respectively, with lower uptake and absorption predicted for the higher MW analogs. Lower absorption was predicted from exposures in a more lipophilic vehicle (1-octanol). Modeled inhalation exposures afforded the highest pulmonary absorption for the MDI monomers (38-54%), with 3-27% for the MW range of 381-751, and <0.1% for the remaining, higher MW derivatives. Predicted oral absorption, representing mucociliary transport, ranged from 5 to 10% for the MDI monomers, 10-25% for constituents of MW 381-751, and ≤3% for constituents with MW > 900. These in silico evaluations should be useful in category-based, worst-case, Read-Across assessments for MDI monomers and modified MDI substances for potential systemic effects. Predictions of appreciable mucociliary transport may also be useful to address data gaps in oral toxicity testing for this category of compounds.

Occurrence and risk assessment of volatile organic compounds in multiple drinking water sources in the Yangtze River Delta region, China

Volatile organic compounds (VOCs) are widely present in water environment, which can threaten ecological sustainability and human health. The concentrations of VOCs and their ecological risks in drinking water are of great concern to human beings. Therefore, 54 kinds of VOCs were investigated from 58 locations of the Yangtze River Delta Region (Yangtze River, Qiantang River, Huangpu River, Taihu Lake and Jiaxing Urban River). Out of 54 target compounds, only 31 VOCs were detected, with total concentrations ranging from 0.570 to 46.820 μg/L from 58 locations of all drinking water sources. Among all detected VOCs compounds, only toluene and styrene can cause high-level ecological risk at location TH-2 of Taihu Lake. According to the carcinogenic and non-carcinogenic risk index, compounds such as 1,2-dichloroethane, bromodichloromethane and 1,1,2-trichloroethane posed a higher carcinogenic risk, and 1,2-dichloroethane, trichloroethylene and toluene posed a higher non-carcinogenic risk. Olfactory risks of water bodies in the Yangtze River Delta region are negligible. Although the concentrations of VOCs in the Yangtze River Delta region did not exceed national standards in China and guidelines of the World Health Organization (WHO) for drinking water, the presence of some ecological and health risks indicated that future monitoring studies and control practices are important to ensure ecological safety of drinking water sources.

Hematological and histological changes from ingestion of Deepwater Horizon crude oil in zebra finches (Taeniopygia guttata)

Exposure to crude oil during spill events causes a variety of pathologic effects in birds, including oxidative injury to erythrocytes, which is characterized in some species by the formation of Heinz bodies and subsequent anemia. However, not all species appear to develop Heinz bodies or anemia when exposed to oil, and there are limited controlled experiments that use both light and electron microscopy to evaluate structural changes within erythrocytes following oil exposure. In this study, we orally dosed zebra finches (Taeniopygia guttata) with 3.3 or 10 mL/kg of artificially weathered Deepwater Horizon crude oil or 10 mL/kg of peanut oil (vehicle control) daily for 15 days. We found that birds receiving the highest dosage experienced a significant increase in reticulocyte percentage, mean corpuscular hemoglobin concentration, and liver mass, as well as inflammation of the gastrointestinal tract and lymphocyte proliferation in the spleen. However, we found no evidence of Heinz body formation based on both light and transmission electron microscopy. Although there was a tendency for packed cell volume and hemoglobin to decrease in birds from the high dose group compared to control and low dose groups, the changes were not statistically significant. Our results indicate that additional experimental dosing studies are needed to understand factors (e.g., dose- and species-specific sensitivity) and confounding variables (e.g., dispersants) that contribute to the presence and severity of anemia resulting from oil exposure in birds.

Mineral oil in food, cosmetic products, and in products regulated by other legislations

For a few years, mineral oils and their potential adverse health effects have been a constant issue of concern in many regulatory areas such as food, cosmetics, other consumer products, and industrial chemicals. Analytically, two fractions can be distinguished: mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). This paper aims at assessing the bioaccumulative potential and associated histopathological effects of MOSH as well as the carcinogenic potential of MOAH for consumer-relevant mineral oils. It also covers the absorption, distribution, metabolism, and excretion of MOSH and MOAH upon oral and dermal exposures. The use and occurrence of consumer-relevant, highly refined mineral oils in food, cosmetics and medicinal products are summarized, and estimates for the exposure of consumers are provided. Also addressed are the challenges in characterizing the substance identity of mineral oil products under REACH. Evidence from more recent autopsy and biopsy studies, along with information on decreasing food contamination levels, indicates a low risk for adverse hepatic lesions that may arise from the retention of MOSH in the liver. With respect to MOAH, at present there is no indication of any carcinogenic effects in animals dermally or orally exposed to highly refined mineral oils and waxes. Such products are used not only in cosmetics but also in medicinal products and as additives in food contact materials. The safety of these mineral oil-containing products is thus indirectly documented by their prevalent and long-term use, with a simultaneous lack of clinical and epidemiological evidence for adverse health effects.

In vitro skin penetration of petrolatum and soybean oil and effects of glyceryl monooleate

OBJECTIVES

Petrolatum and soybean oil are common ingredients incorporated in topical skin formulations for skin protection and moisturization. However, the stratum corneum (SC) penetration kinetics of these two cosmetic ingredients has not been systematically studied. Glyceryl monooleate (GlyMOle) has been shown to enhance skin penetration of various compounds. It was hypothesized that GlyMOle could enhance skin penetration of petrolatum and soybean oil. This study aimed to examine the in vitro skin penetration of petrolatum and soybean oil in the presence or absence of GlyMOle.

METHODS

Skin permeation experiments were conducted using the in vitro Franz diffusion cell model with split-thickness human skin and human epidermal membrane (HEM). The effect of permeant dose and the kinetics of permeant penetration were examined with and without GlyMOle in vitro.

RESULTS

Petrolatum and soybean oil were found to permeate across HEM, and no effect of GlyMOle on skin permeation into the receptor chamber was observed. GlyMOle enhanced the penetration of petrolatum into the split-thickness skin at 50 μg dose (petrolatum:GlyMOle, 49 : 1, w/w). However, no effect of GlyMOle on petrolatum penetration was observed at 200 μg dose (of the same petrolatum:GlyMOle ratio), indicating a dose-dependent effect. GlyMOle at the level used in the study did not enhance the penetration of soybean oil with 50 and 200 μg doses at any timepoints.

CONCLUSION

GlyMOle was a skin penetration enhancer for petrolatum under the in vitro conditions identified in this study.

Review of data on the dermal penetration of mineral oils and waxes used in cosmetic applications

Mineral oils and waxes used in cosmetic products, also referred to as "personal care products" outside the European Union, are mixtures of predominantly saturated hydrocarbons consisting of straight-chain, branched and ring structures with carbon chain lengths greater than C16. They are used in skin and lip care cosmetic products due to their excellent skin tolerance as well as their high protecting and cleansing performance and broad viscosity options. Recently, concerns have been raised regarding potential adverse health effects of mineral oils and waxes from dermal application of cosmetics. In order to be able to assess the risk for the consumer the dermal penetration potential of these ingredients has to be evaluated. The scope and objective of this review are to identify and summarize publicly available literature on the dermal penetration of mineral oils and waxes as used in cosmetic products. For this purpose, a comprehensive literature search was conducted. A total of 13 in vivo (human, animal) and in vitro studies investigating the dermal penetration of mineral oils and waxes has been identified and analysed. The majority of the substances were dermally adsorbed to the stratum corneum and only a minor fraction reached deeper skin layers. Overall, there is no evidence from the various studies that mineral oils and waxes are percutaneously absorbed and become systemically available. Thus, given the absence of dermal uptake, mineral oils and waxes as used in cosmetic products do not present a risk to the health of the consumer.

Petrolatum: Barrier repair and antimicrobial responses underlying this "inert" moisturizer

BACKGROUND

Petrolatum is a common moisturizer often used in the prevention of skin infections after ambulatory surgeries and as a maintenance therapy of atopic dermatitis (AD). However, the molecular responses induced by petrolatum in the skin have never been assessed.

OBJECTIVE

We sought to define the cutaneous molecular and structural effects induced by petrolatum.

METHODS

Thirty-six healthy subjects and 13 patients with moderate AD (mean SCORAD score, 39) were studied by using RT-PCR, gene arrays, immunohistochemistry, and immunofluorescence performed on control skin, petrolatum-occluded skin, and skin occluded with a Finn chamber only.

RESULTS

Significant upregulations of antimicrobial peptides (S100A8/fold change [FCH], 13.04; S100A9/FCH, 11.28; CCL20/FCH, 8.36; PI3 [elafin]/FCH, 15.40; lipocalin 2/FCH, 6.94, human β-defensin 2 [DEFB4A]/FCH, 4.96; P < .001 for all) and innate immune genes (IL6, IL8, and IL1B; P < .01) were observed in petrolatum-occluded skin compared with expression in both control and occluded-only skin. Application of petrolatum also induced expression of key barrier differentiation markers (filaggrin and loricrin), increased stratum corneum thickness, and significantly reduced T-cell infiltrates in the setting of "normal-appearing" or nonlesional AD skin, which is known to harbor barrier and immune defects.

CONCLUSIONS

Petrolatum robustly modulates antimicrobials and epidermal differentiation barrier measures. These data shed light on the beneficial molecular responses of petrolatum in barrier-defective states, such as AD and postoperative wound care.