Light-emitting diodes (LED) for domestic lighting: any risks for the eye?

Light-emitting diodes (LEDs) are taking an increasing place in the market of domestic lighting because they produce light with low energy consumption. In the EU, by 2016, no traditional incandescent light sources will be available and LEDs may become the major domestic light sources. Due to specific spectral and energetic characteristics of white LEDs as compared to other domestic light sources, some concerns have been raised regarding their safety for human health and particularly potential harmful risks for the eye. To conduct a health risk assessment on systems using LEDs, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), a public body reporting to the French Ministers for ecology, for health and for employment, has organized a task group. This group consisted physicists, lighting and metrology specialists, retinal biologist and ophthalmologist who have worked together for a year. Part of this work has comprised the evaluation of group risks of different white LEDs commercialized on the French market, according to the standards and found that some of these lights belonged to the group risk 1 or 2. This paper gives a comprehensive analysis of the potential risks of white LEDs, taking into account pre-clinical knowledge as well as epidemiologic studies and reports the French Agency's recommendations to avoid potential retinal hazards.

Diagnostic and neural analysis of skin cancer (DANAOS). A multicentre study for collection and computer-aided analysis of data from pigmented skin lesions using digital dermoscopy.

BACKGROUND: Early detection of melanomas by means of diverse screening campaigns is an important step towards a reduction in mortality. Computer-aided analysis of digital images obtained by dermoscopy has been reported to be an accurate, practical and time-saving tool for the evaluation of pigmented skin lesions (PSLs). A prototype for the computer-aided diagnosis of PSLs using artificial neural networks (NNs) has recently been developed: diagnostic and neural analysis of skin cancer (DANAOS). OBJECTIVES: To demonstrate the accuracy of PSL diagnosis by the DANAOS expert system, a multicentre study on a diverse multinational population was conducted. METHODS: A calibrated camera system was developed and used to collect images of PSLs in a multicentre study in 13 dermatology centres in nine European countries. The dataset was used to train an NN expert system for the computer-aided diagnosis of melanoma. We analysed different aspects of the data collection and its influence on the performance of the expert system. The NN expert system was trained with a dataset of 2218 dermoscopic images of PSLs. RESULTS: The resulting expert system showed a performance similar to that of dermatologists as published in the literature. The performance depended on the size and quality of the database and its selection. CONCLUSIONS: The need for a large database, the usefulness of multicentre data collection, as well as the benefit of a representative collection of cases from clinical practice, were demonstrated in this trial. Images that were difficult to classify using the NN expert system were not identical to those found difficult to classify by clinicians. We suggest therefore that the combination of clinician and computer may potentially increase the accuracy of PSL diagnosis. This may result in improved detection of melanoma and a reduction in unnecessary excisions.

Immediate effects of UV radiation on the skin: modification by an antioxidant complex containing carotenoids.

BACKGROUND/AIMS: The ultraviolet (UV) portion of sunlight is involved in the induction and development of skin cancers against which a limited photoprotection may be provided by reduced time of exposure, clothing, and sunscreen applications. The concept of an effective, safe, systemic photoprotection will circumvent many of the shortcomings. The UV-induced oxidative stress is a cause of DNA damage and a few publications have shown, in humans, minimal benefits, if any, of the oral intake of antioxidant complex, contrasting with the large literature showing beneficial effects in vitro or in animal models. METHODS: We investigated, in 25 healthy individuals, the capacity of an antioxidant complex (AOC) - vitamins (lycopene, beta-carotene, alpha-tocopherol), selenium - to reduce UV-induced damages. The AOC was administered orally, daily during 7 weeks. Before and after irradiations, before and after the intake of the product, six parameters were studied: skin color by chromametry, minimal erythemal dose and, on skin biopsies, sunburn cells (SBCs), p53 detected by immunohistochemistry, pigmentation index, and levels of lipoperoxides (thiobarbituric acid reaction). RESULTS: After the oral intake of AOC, we observed an elevation of the actinic erythema threshold (+20%, P=0.01) and a general reduction of the UV-induced erythemas, a reduction of the UV-induced p53 expression (P<0.05) and of SBCs (P<0.01), and a parallel reduction of the lipoperoxide levels (P<0.01). The pigmentation was increased (P<0.01). CONCLUSION: After the oral intake of an antioxidant complex, many parameters of the epidermal defense against UV-induced damages are significantly improved. The oral intake of AOC could provide a safe, daylong and efficient complement to photo-protective measures provided by topical and physical agents and may contribute to reduce the DNA damages leading to skin aging and skin cancers.

Sunscreen use and intentional exposure to ultraviolet A and B radiation: a double blind randomized trial using personal dosimeters.

A previous randomized trial found that sunscreen use could extend intentional sun exposure, thereby possibly increasing the risk of cutaneous melanoma. In a similarly designed trial, we examined the effect of the use of sunscreens having different sun protection factor (SPF) on actual exposure to ultraviolet B (UVB) and ultraviolet A (UVA) radiation. In June 1998, 58 European participants 18-24 years old were randomized to receive a SPF 10 or 30 sunscreens and were asked to complete daily records of their sun exposure during their summer holidays of whom 44 utilized a personal UVA and UVB dosimeter in a standard way during their sunbathing sessions. The median daily sunbathing duration was 2.4 hours in the SPF 10 group and 3.0 hours in the SPF 30 group (P = 0.054). The increase in daily sunbathing duration was paralleled by an increase in daily UVB exposure, but not by changes in UVA or UVB accumulated over all sunbathing sessions, or in daily UVA exposure. Of all participants, those who used the SPF 30 sunscreen and had no sunburn spent the highest number of hours in sunbathing activities. Differences between the two SPF groups in total number of sunbathing hours, daily sunbathing duration, and daily UVB exposure were largest among participants without sunburn during holidays. Among those with sunburn, the differences between the two groups tended to reduce. In conclusion, sunscreens used during sunbathing tended to increase the duration of exposures to doses of ultraviolet radiation below the sunburn threshold.

Randomised trial of interferon alpha-2a as adjuvant therapy in resected primary melanoma thicker than 1.5 mm without clinically detectable node metastases. French Cooperative Group on Melanoma.

BACKGROUND: Owing to the limited efficacy of therapy on melanoma at the stage of distant metastases, a well-tolerated adjuvant therapy is needed for patients with high-risk primary melanoma. Our hypothesis was that an adjuvant treatment with low doses of interferon alpha could be effective in patients with localised melanoma. METHODS: After resection of a primary cutaneous melanoma thicker than 1.5 mm, patients without clinically detectable node metastases were randomly assigned to receive either 3x10(6) IU interferon alpha-2a, three-times weekly for 18 months, or no treatment. The primary endpoint was the relapse-free interval. FINDINGS: 499 patients were enrolled, of whom 489 were eligible. When used as part of a sequential procedure, interferon alpha-2a was of significant benefit for relapse-free interval (p=0.038). A long-term analysis, after a median follow-up of 5 years, showed a significant extension of relapse-free interval (p=0.035) and a clear trend towards an increase in overall survival (p=0.059) in interferon alpha-2a-treated patients compared with controls. There were 100 relapses and 59 deaths among the 244 interferon alpha-2a-treated patients compared with 119 relapses and 76 deaths among the 245 controls. The estimated 3-year-relapse rates were 32% in the interferon alpha-2a group and 44% in controls; the 3-year death rates were 15% and 21%, respectively. Only 10% of patients experienced WHO grade 3 or 4 adverse events. Treatment was compatible with normal daily life. INTERPRETATION: Adjuvant therapy of high-risk melanoma with low doses of interferon alpha-2a for 18 months is safe and is beneficial when started before clinically detectable node metastases develop.

Should subjects who used psoralen suntan activators be screened for melanoma? Epidemiology and Prevention Subgroup, EORTC Melanoma Cooperative Group EORTC Prevention Research Division.

BACKGROUND: Psoralens are potent tanning activators that have been introduced in France and in Belgium in some tanning lotions and sunscreens. It was shown that poor tanners who ever used psoralen tanning activators display a four-fold increase in melanoma risk when compared to poor tanners using regular sunscreens. Although psoralens have now banned from suntan lotions, it is likely that the increase in melanoma risk linked to their previous use will persist for several years. METHODS: The melanoma risk attributable to psoralens use was calculated to evaluate the population at risk in France and Belgium. RESULTS: Melanoma incidence for the year 1995 was estimated to be of 10.2 per 100,000 in France and of 10.0 per 100,000 in Belgium, representing 5,900 and 1,000 melanoma cases. From the melanoma incidence among poor tanner who ever used psoralens (52 per 100,000) and estimation of the percentage of psoralen users among poor tanners, it can be derived that, for the year 1995, 267 melanoma cases could be attributed to psoralen tanning activators. CONCLUSIONS: Subjects who used psoralen suntan activators should be informed of their increased melanoma risk and be encouraged to participate in clinical programmes for early detection of melanoma, more especially when they are poor tanners and display a high naevi count. Such an action could save a significant number of lives.

Melanoma risk and residence in sunny areas. EORTC Melanoma Co-operative Group. European Organization for Research and Treatment of Cancer.

Melanoma risk among subjects from Germany, France and Belgium who had lived for 1 year or more in sunny climates was examined in a one-to-one unmatched case-control study conducted among white subjects 20 years old or more. A total of 412 consecutive patients with melanoma diagnosed from 1 January 1991 onwards, were derived from hospital registers; 445 controls were randomly chosen in the same municipality as the cases. After adjustment for host characteristics, melanoma risk associated with residence in a sunny area was 2.7 (95% CI: 1.4-5.2), increasing to 4.7 (95% CI: 1.4-13.5) if subjects sought a suntan when residing in sunny climates, and to 4.3 (95% CI: 1.7-11.1) if subjects arrived before the age of 10 years in the sunny area. Residence in sunny areas and recreational sun exposure seemed to combine their effects on melanoma risk. Increase in melanoma risk conveyed by deliberate sun exposure during adulthood was highest among subjects who had lived in sunny areas as a child or adolescent and lowest among subjects who had never resided in sunny areas. Our results support conclusions from migrant studies that indicated that childhood is a critical period of either vulnerability to solar radiation or more frequent exposures to melanoma risk factors. They also suggest that moderate sun exposure of an adult who was heavily sun exposed in childhood is associated with a higher melanoma risk than that of high sun exposure of an adult who was sun protected in childhood.

Melanoma and use of sunscreens: an Eortc case-control study in Germany, Belgium and France. The EORTC Melanoma Cooperative Group.

Use of sunscreens is widely advocated as a preventive measure against sun-induced skin cancers. However, to date, no epidemiologic study has reported a decreased melanoma risk associated with sunscreen use. We have conducted a case-control study aimed at evaluating the influence of sunscreen use on the occurrence of cutaneous malignant melanoma. In 1991 and 1992, 418 melanoma cases and 438 healthy controls were interviewed in Germany, France and Belgium. The questionnaire used differentiated between regular sunscreens, psoralen sunscreen (prepared with 5-methoxypsoralen, a tanning activator and photocarcinogen), and self-tanning cosmetics (which produce a tan without ultraviolet radiation). After adjusting for age, sex, hair colour and holiday weeks spent each year in sunny resorts, the melanoma risk was of 1.50 (95% Cl:1.09-2.06) for regular sunscreens, and of 2.28 (95% Cl: 1.28-4.04) for psoralen sunscreens. No melanoma risk was associated with use of self-tanning cosmetics. Among subjects with a poor ability to tan, psoralen sunscreen users displayed a melanoma risk of 4.45 (95% Cl: 1.25-15.8) when compared with regular sunscreen users. There was a significant negative interaction between regular sunscreen use and sunburns experienced in adulthood. Use of sunscreens, especially psoralen sunscreen, was associated with higher density of pigmented lesions of the skin. Although we cannot exclude the presence of an unknown confounding factor, our results support the hypothesis that sunscreens do not protect against melanoma, probably because of their ability to delay or avoid sunburn episodes, which may allow prolonged exposure to unfiltered ultraviolet radiation. Serious doubts are raised regarding the safety of sunscreens containing psoralens.

Cutaneous malignant melanoma and exposure to sunlamps or sunbeds: an EORTC multicenter case-control study in Belgium, France and Germany. EORTC Melanoma Cooperative Group.

The study objective was to assess whether exposure to sunlamps and sunbeds represents a risk factor for cutaneous malignant melanoma (CMM). A 1-to-1 unmatched case-control study was conducted among subjects 20 years old or more with naturally non-pigmented skin in Germany, France and Belgium. A total of 420 consecutive patients with CMM diagnosed from 1 January 1991 onward were derived from hospital registers; 447 controls with no history of skin cancer were chosen at random in the same municipality as the cases. Exposure to sunlamps or sunbeds starting before 1980 is associated with a crude estimated risk of CMM of 2.71 (95% CI: 1.06-7.78) for at least 10 hr of accumulated exposure. This risk is of 2.12 (95% CI: 0.84-5.37) after adjustment for age, sex, hair colour and average number of holiday weeks each year in sunny resorts. Subjects who experienced skin-burn due to sunlamps or sunbeds, and who had accumulated at least 10 hr of exposure, displayed a crude estimated CMM risk of 4.47 (95% CI: 1.45-13.7), which rose to 8.97 (95% CI: 2.10-38.6) for those who exposed their skin for tanning purposes. The risk associated with skin-burn is only marginally modified after multiple adjustments for host characteristics and recreational exposure to sunlight. Apparently, sunlamps and sunbeds share the increased risk of CMM, which seems to concentrate in subjects exhibiting hazardous behaviour towards ultraviolet radiation sources. However, although it is reasonable to believe that high doses of pure ultraviolet A radiation can be dangerous, this is not firmly established by this study. Most exposures to ultraviolet A tanning devices began after 1980; therefore, epidemiologic studies have difficulty in revealing any increase in risk of CMM starting after 1980 because of the latent period between exposure and occurrence of melanoma. Public health authorities should have a cautious approach towards the rapidly developing fashion of tanning under sunlamps or sunbeds.

Intractable infant diarrhea associated with phenotypic abnormalities and immunodeficiency.

We report on eight children with severe diarrhea beginning in the first 6 months of life (< 1 month in six cases), who had a number of features in common. All were small for gestational age and had an abnormal phenotype, including facial dysmorphism, hypertelorism, and woolly, easily removable hair with trichorhexis nodosa. Two were products of consanguineous marriages. Severe secretory diarrhea persisted despite bowel rest (n = 7). Jejunal biopsy specimens showed total or subtotal villous atrophy with crypt necrosis, and inconstant T-cell activation in some cases (n = 3). Colon biopsy specimens showed moderate nonspecific colitis. All the patients had defective antibody responses despite normal serum immunoglobulin levels, and defective antigen-specific skin tests despite positive proliferative responses in vitro. Three had monoclonal hyper-immunoglobulinemia A. The course was marked by diffuse erythroderma in two cases and mental retardation in three. Treatment included bowel rest, intravenous administration of immune globulins, administration of corticosteroids (n = 6) and cyclosporine (n = 2), and bone marrow transplantation (n = 1). Five patients died between the ages of 2 and 5 years (of sepsis or cirrhosis), two are being fed enterally, and one continues to receive total parenteral nutrition. The cause of the combined low birth weight, dysmorphism, severe diarrhea, trichorrhexis, and immunodeficiency is unclear. These features may constitute a specific syndrome within the group of intractable diarrheas of infancy.

Recreational exposure to sunlight and lack of information as risk factors for cutaneous malignant melanoma. Results of an European Organization for Research and Treatment of Cancer (EORTC) case-control study in Belgium, France and Germany. The EORTC Malignant Melanoma Cooperative Group.

This study addressed the impact of exposure to ultraviolet radiation on the risk of cutaneous malignant melanoma (CMM), as well as the behavioral components at stake in its occurrence. We performed a one-to-one unmatched case-control study among subjects aged 20 years or more with naturally non-pigmented skin in Germany, France and Belgium. Four-hundred and twenty consecutive patients with CMM diagnosed from 1 January 1991 on were derived from hospital registries; 447 controls were chosen randomly in the same municipality as cases. Subjects unaware of the dangers of exaggerated exposure to sunlight display an estimated CMM risk of 3.72% (95% confidence interval 2.63-5.26). The number of holiday weeks spent annually in sunny resorts and sunbathing during the hot hours of the day are strong risk factors in the three countries, but not the number of years spent outdoors, as farmers or building workers. Multiple logistic adjustments on the host characteristics increases the CMM risk associated with recreational exposure to sunlight, as well as the adjustment on the unawareness of the dangers of exaggerated exposure to sunlight. Recreational exposure to sunlight and sunburn early in life seem capable of fostering the proliferation of pigmented lesions of the skin. Our data support the hypothesis that most CMM develop from pigmented lesions of the skin containing initiated melanocytes, and that the cell proliferation due to brutal, intermittent exposures to solar radiation amplifies the likelihood of a melanocyte entering into a malignant process.(ABSTRACT TRUNCATED AT 250 WORDS)

Validity of the histopathological criteria used for diagnosing dysplastic naevi. An interobserver study by the pathology subgroup of the EORTC Malignant Melanoma Cooperative Group.

Ten (dermato)pathologists studied 50 cutaneous melanocytic lesions including common naevocellular naevi, dysplastic naevi (DN), melanomas in situ and invasive primary melanomas, with emphasis on the histological criteria of DN. Using a standardised form, 20 defined histopathological features were scored (semi)quantitatively. Concordance of diagnosis, efficacy and reproducibility of features were investigated. DN were distinguished well from the other entities (mean Po 0.87). Agreement on the degree of atypia of DN was low. The reproducibility of the scoring was best for the following features: irregular nests, lymphohistiocytic infiltrate, marked junctional proliferation and large nuclei. The overall values of these features to discriminate between DN and non-DN were better than for the other features studied. Using the presence of at least three of the four features as a condition for the diagnosis of DN, values for sensitivity, specificity and positive and negative predictive values were 0.86, 0.91, 0.96 and 0.73, respectively. On the basis of the results these features seem best suited as histological criteria for the diagnosis of DN.

[Biological effects of solar radiations]. / Les effets biologiques des radiations solaires.

Main biological effects of ultra-violet radiations are discussed. At a dermatological point of view, most of these effects are harmful: actinic erythema, cutaneous cancerogenesis (basal and spinous cell carcinomas, malignant cutaneous melanomas). Photo-immunosuppression and photoaging of the skin are discussed. Two benefic actions of sunlight are reviewed: synthesis of vitamin D3 and positive action of visible radiations on human psychism.

[Histology and physiology of black skin]. / Histologie et physiologie de la peau noire.

The aim of this article is to review the experimental knowledge concerning black skin. We point out its histological and physiological features without discussing here the specific pathology of black patients. Under the microscope skin structure is roughly the same in all races, but morphological differences exist, particularly within the epidermis, with potential practical consequences. In comparison with white skin, the black skin stratum corneum is equal in thickness but more compact: about twenty cell layers are observed in blacks versus sixteen layers in whites. The lipid content of black epidermis is also somewhat higher, and this perhaps explains the greater cellular cohesion, hence the difficulty in stripping off the black horny layer. These findings could also explain a slightly inferior permeability of black skin to certain chemicals. The hair of blacks in naturally more brittle and more susceptible to breakage and spontaneous knotting than that of whites. The kinky or wooly form of black hair, the weak intercellular cohesion between cortical cells and the specific hair grooming practices among black people account for these effects. The higher electrical resistance of black skin suggests that the black epidermis would be less hydrated than white epidermis. Anatomically, the amount of sweat glands in black and white skins is identical and varies with climatic changes but not with racial factors. Likewise, sweating is thought to be similar in both races, taking into account the contradictory results from studies, but black subjects withstand humid heat better while whites cope better with dry heat.(ABSTRACT TRUNCATED AT 250 WORDS)