Sea water or its components alter experimental irritant dermatitis in man

Irritant Contact Dermatitis — a Review

Purpose of Review

Recent Findings

Summary

GuLF DREAM: A Model to Estimate Dermal Exposure Among Oil Spill Response and Clean-up Workers

Tens of thousands of individuals performed oil spill response and clean-up (OSRC) activities following the 'Deepwater Horizon' oil drilling rig explosion in 2010. Many were exposed to oil residues and dispersants. The US National Institute of Environmental Health Sciences assembled a cohort of nearly 33 000 workers to investigate potential adverse health effects of oil spill exposures. Estimates of dermal and inhalation exposure are required for those individuals. Ambient breathing-zone measurements taken at the time of the spill were used to estimate inhalation exposures for participants in the GuLF STUDY (Gulf Long-term Follow-up Study), but no dermal measurements were collected. Consequently, a modelling approach was used to estimate dermal exposures. We sought to modify DREAM (DeRmal Exposure Assessment Method) to optimize the model for assessing exposure to various oil spill-related substances and to incorporate advances in dermal exposure research. Each DREAM parameter was reviewed in the context of literature published since 2000 and modified where appropriate. To reflect the environment in which the OSRC work took place, the model treatment of evaporation was expanded to include vapour pressure and wind speed, and the effect of seawater on exposure was added. The modified model is called GuLF DREAM and exposure is estimated in GuLF DREAM units (GDU). An external validation to assess the performance of the model for oils, tars, and fuels was conducted using available published dermal wipe measurements of heavy fuel oil (HFO) and dermal hand wash measurements of asphalt. Overall, measured exposures had moderate correlations with GDU estimates (r = 0.59) with specific correlations of -0.48 for HFO and 0.68 for asphalt. The GuLF DREAM model described in this article has been used to generate dermal exposure estimates for the GuLF STUDY. Many of the updates made were generic, so the updated model may be useful for other dermal exposure scenarios.

Evaluation of new Seawater-based Mouth Rinse Versus Chlorhexidine 0.2% Reducing Plaque and Gingivitis Indexes. A Randomized Controlled Pilot Study

For a long time, Chlorhexidine digluconate (CHX) has been considered the most used mouth-rinse for reducing plaque and gingivitis. Sea4® Encias is a new seawater-based mouth rinse with a similar action to CHX. Its prolonged use produces fewer side effects. This study compared the effects of two oral rinses: Chlorhexidine 0.20% and Sea 4® Encias (seawater) for reducing plaque and gingivitis indices. This double-blind crossover study recruited and monitored 93 volunteer dental students, hygienists and doctors from the Universidad Católica de Murcia (UCAM), for 1 month, and compared the efficacy of Chlorhexidine 0.20% (Group A); Sea4® Encías (Group B); and a placebo saline solution (Group C) mouth-rinses for reducing plaque and gingivitis indices. Plaque and gingival inflammation (Löe and Silness test) were evaluated at baseline and after each study stage. Group A reduced plaque growth and gingivitis significantly compared with Groups B and C; Group B was more effective than Group C. The mean P.I. decreased similarly in groups A and B. However, Group A showed the statistically significant value compared with other groups. Group A and group B, showed greater reduction in Gingival Indexes compared with group C. The Sea4 mouthwash showed better inhibitory activity on plaque (1.32 ± 0.22) compared with CHX (1.97 ± 0.34) and saline (2.78 ± 0.11). Sea4 Encias and Chlorhexidine 0.20% mouth-rinses significantly reduce plaque growth and G.I. compared with saline mouth-rinse; Sea4 Encías mouth-rinse is more effective against plaque regrowth than Chlorhexidine in this pilot study.

A randomized multicenter study comparing seawater washes and carmellose artificial tears eyedrops in the treatment of dry eye syndrome

PURPOSE

To investigate the safety and efficacy of sterile isotonic seawater washes vs standard treatment with carmellose artificial tears in dry eye syndrome (DES).

PATIENTS AND METHODS

This is a randomized multicenter prospective study with 12 weeks of follow-up. A group of patients with DES (N=60) were treated with seawater spray (Quinton®) five times daily, and another similar group (N=60) were treated with carmellose artificial tears eyedrops (Viscofresh® 0.5%) five times a day. The parameters studied and measured were as follows: Ocular Surface Disease Index questionnaire score, Schirmer I test (without anesthesia) score, tear osmolarity (TearLab®), tear breakup time, tear meniscus height (meniscography OCT), fluorescein corneal staining score (National Eye Institute scale), lissamine green conjunctival staining score, and levels of IL-1 beta and IL-6 in tears (Luminex® 200).

RESULTS

In the group treated with seawater, symptoms decreased by 68%, and the decrease was 26% statistically superior to the group treated with carmellose artificial tears eyedrops (P<.001). Levels of IL-1 beta and IL-6 in tears significantly decreased in the seawater group compared to the carmellose artificial tears group (19%/17% vs 52%/51%) (P<0.001). There were no statistically significant differences in the other measured parameters. There were no cases of poor tolerance or side effects.

CONCLUSION

Administration of seawater is more effective than treatment with carmellose artificial tears in reducing symptoms and pro-inflammatory molecules (IL-1 beta and IL-6) in tears of patients with DES.

Salt water and skin interactions: new lines of evidence

In Health Resort Medicine, both balneotherapy and thalassotherapy, salt waters and their peloids, or mud products are mainly used to treat rheumatic and skin disorders. These therapeutic agents act jointly via numerous mechanical, thermal, and chemical mechanisms. In this review, we examine a new mechanism of action specific to saline waters. When topically administered, this water rich in sodium and chloride penetrates the skin where it is able to modify cellular osmotic pressure and stimulate nerve receptors in the skin via cell membrane ion channels known as "Piezo" proteins. We describe several models of cutaneous adsorption/desorption and penetration of dissolved ions in mineral waters through the skin (osmosis and cell volume mechanisms in keratinocytes) and examine the role of these resources in stimulating cutaneous nerve receptors. The actions of salt mineral waters are mediated by a mechanism conditioned by the concentration and quality of their salts involving cellular osmosis-mediated activation/inhibition of cell apoptotic or necrotic processes. In turn, this osmotic mechanism modulates the recently described mechanosensitive piezoelectric channels.

Effect of São Pedro do Sul thermal water on skin irritation

Many mineral waters are known for centuries for treating dermatological diseases but there is little scientific evaluation of the effects of these waters in skin. A total of 17 healthy Caucasian volunteers, including men and women, were enrolled in this study. Two skin sites were marked on each volunteer forearm and irritated with sodium lauryl sulphate at 2% (w/v) kept under occlusion for 24 h with Finn chambers. Afterwards, purified water or São Pedro do Sul (SPS) thermal water were applied to the irritated skin sites, and kept under occlusion for 48 h also with Finn chambers. Transepidermal water loss (TEWL) was used as a measure of the skin barrier function to evaluate the potential anti-irritant effect of the thermal water on skin. Statistically significant differences in the mean TEWL variations were observed for the skin treated with SPS thermal water and with purified water (P = 0.036). The thermal water reduced the degree to which the skin barrier was disrupted compared with purified water alone in 82.4% of the volunteers. The SPS thermal water is anti-irritant and, therefore, can be helpful to relieve skin irritation and in cosmetic formulations to improve the tolerability of the products.

Enhancement of keratinocyte differentiation by rose absolute oil

BACKGROUND

Through differentiation processes, keratinocytes provide a physical barrier to our bodies and control skin features such as moisturization, wrinkles and pigmentation. Keratinocyte differentiation is disturbed in several skin diseases such as psoriasis and atopic dermatitis.

OBJECTIVE

The aim of this study is to evaluate the keratinocyte differentiation-enhancing effect of rose absolute oil (RAO).

METHODS

Primary cultured human normal keratinocytes were treated with RAO, and differentiation then checked by the expression of marker genes.

RESULTS

RAO did not induce cytotoxicity on cultured keratinocytes at a dose of 10microM. The level of involucrin, an early marker for keratinocyte differentiation, was significantly increased by RAO. Concomitantly, RAO increased involucrin promoter activity, indicating that RAO increased involucrin gene expression at the mRNA level. Furthermore, RAO increased the level of filaggrin in cultured keratinocytes, and in the granular layer of mouse skin. In line with these results, RAO decreased the proliferation of keratinocytes cultured in vitro. When RAO was applied topically on the tape-stripped mouse skins, it accelerated the recovery of disturbed barrier function.

CONCLUSION

These results suggest that RAO may be applicable for the control of skin texture and keratinocyte differentiation-related skin diseases.

Water, salts and skin barrier of normal skin

BACKGROUND

We recently reported that open application of seawater for 20 min ameliorated experimental irritant contact dermatitis induced by sodium lauryl sulphate (SLS) cumulative irritation. The efficacy was overall contributed by 500 mm of sodium chloride (NaCI) and 10 mm of potassium chloride (KCl), which are consistent with the each concentration in seawater. Although the usefulness of mineral water with 500 mm NaCl and 10 mm KCl to treat atopic dermatitis (AD) or irritated skin was considered, seawater or its components would induce a feel of stinging in patients with AD. Furthermore, 20 min application was thought to be too long to use everyday as a treatment.

OBJECTIVE

We report the effects of 3 types of mineral water with NaCl and KCl to check the further efficacy with lesser stinging by 2 min application.

RESULTS

A mineral water with 250 mm NaCl and 50 mm KCl was the most effective water to prevent disruption of skin barrier and stratum corneum water content after cumulating irritation by SLS. Moreover, improvement of skin dryness and pruritus were shown 2 weeks after the application of the mineral water to a 6-year-old boy with atopic dermatitis.

CONCLUSION

Our results suggested the possible usefulness of the mineral water with 250 mm NaCl and 50 mm KCl as the therapy of atopic dermatitis of other chronic dermatitis. Although the mineral water would not cure those skin diseases, it could be an adjunctive therapy. Further controlled clinical trials with evaluation by TEWL and capacitance are required to declare the efficacy of the mineral water in the treatment of patients with AD or other chronic dermatitis.

Irritant contact dermatitis: is there an immunologic component?

Irritant contact dermatitis (ICD) describes a multifactorial disease resulting from exposure to occupational irritants. Though often characterized as a localized reaction, there are at least 10 forms of ICD, several of which possess systemic involvement. The exact mode of irritant action in ICD is not completely understood, but recent literature suggests that an immunologic-like component may be present. The correlation between the morphology, clinical manifestations and chemokines involved in allergic contact dermatitis and irritant contact dermatitis will be discussed and studies indicating an irritant "immunologic-like" response will be reviewed and analyzed.

Do cool water or physiologic saline compresses enhance resolution of experimentally-induced irritant contact dermatitis?

Acute irritant contact dermatitis (ICD) is frequently treated with cool water or saline compresses. While presumed effective, little quantitative evaluation documents the treatment's benefit. This study sought to determine the efficacy of both distilled water and physiologic saline compresses on experimentally-induced ICD. 24-h application of both the lipophilic nonanoic acid (NAA) and the hydrophilic sodium lauryl sulfate (SLS) were used to induce irritant contact dermatitis in 9 healthy volunteers. Following irritation, compresses were applied 0.5 h 2x daily for 4 consecutive days. Transepidermal water loss (TEWL), laser Doppler flowmetry (LDF), chromametry and visual scoring were used to quantify results. Cool compresses of both water and saline significantly reduced TEWL and LDF, with no statistically significant difference between the efficacy of the saline or water compresses. Chromametry and visual scoring did not detect a significant effect with either the water or saline compresses. The results suggest an improvement with 2x-daily application of either water or physiologic saline compresses in the treatment of acute ICD, though true clinical benefit will be elucidated through further experimentation. Certainly, the current recommendation regarding the use of cool compresses for treating ICD should not be discarded.