Sun Exposure and the Incidence of Melanocytic Nevi in Young Australian Children

Sun-Protective Clothing Worn Regularly during Early Childhood Reduces the Number of New Melanocytic Nevi: The North Queensland Sun-Safe Clothing Cluster Randomized Controlled Trial

Numerous pigmented moles are associated with sun exposure and melanomarisk. This cluster randomized controlled trial aimed to determine if sun-protective clothing could prevent a significant proportion of the moles developing in young children (ACTRN12617000621314; Australian New Zealand Clinical Trials Registry. Twenty-five childcare centers in Townsville (19.25° S), Australia, were matched on shade provision and socioeconomic status. One center from each pair was randomized to the intervention arm and the other to the control arm. Children at 13 intervention centers wore study garments and legionnaire hats at childcare and received sun-protective swimwear and hats for home use, while children at the 12 control centers did not. The 1–35-month-old children (334 intervention; 210 control) were examined for moles at baseline (1999–2002) and were re-examined annually for up to 4 years. Both groups were similar at baseline. Children at intervention centers acquired fewer new moles overall (median 12.5 versus 16, p = 0.02; 0.46 versus 0.68 moles/month, p = 0.001) and fewer new moles on clothing-protected skin (6 vs. 8; p = 0.021 adjusted for confounding and cluster sampling) than controls. Intervention children had 24.3% fewer new moles overall (26.5 versus 35) and 31.6% (13 versus 19) fewer moles on clothing-protected skin than controls after 3.5 years. Sunlight’s influence on nevogenesis is mitigated when children regularly wear UPF 30-50+ clothing covering half their body, implying that increased clothing cover reduces melanoma risk. Sun-protective clothing standards should mandate reporting of the percentage of garment coverage for childrenswear.

Slip, Slop, Slap, Slide, Seek and Sport: A Systematic Scoping Review of Sun Protection in Sport in Australasia

Australia and New Zealand have the highest incidence of skin cancer. Sport is a fundamental part of Australasian culture, beginning in childhood, often with life-long participation. Participating in outdoor sports can contribute significantly to the lifetime ultraviolet radiation (UVR) dose individuals receive and their risk of developing skin cancer. This systematic scoping review explores the use of sun-protection by outdoor sporting participants in Australasia and considers how sun-protection practices may be improved and better evaluated in the community. A search of electronic databases using the search strategy "sun protection" AND "sport" AND "Australia" yielded 17 studies published in English from January 1992 to August 2021. Study methods included using UV-dosimeters to measure individual UVR-exposure; remote estimates of clothing-adjusted UVR-exposure; direct observation of sun-protection practices; and self-reported sun-exposure and sun-protection. Despite 40 years of 'Slip, Slop, Slap' campaigns in Australia, the use of sun-protection in most outdoor sports is inadequate. The paucity of comparable data limited our analyses, demonstrating a need for standardized, objective evaluation tools. Such tools, if used across a range of sports, should inform the development of workable recommendations that sporting clubs could implement and adopt into policy, thus empowering them to better protect the health of their participants.

Predictive value of global dermoscopic pattern in patients diagnosed with cutaneous melanoma

Introduction

Dermoscopy is one of the most commonly used methods in early diagnosis of melanoma. It is conducted to differentiate between benign and malignant patterns in melanocytic lesions.

Aim

To determine if there is a predominance of one dermoscopic pattern in patients with melanoma and if there is a significant difference in dominant global dermoscopic pattern in patients with cutaneous melanomas correlated with patients’ sex and the location of the primary tumor.

Material and methods

The study included 162 patients with prior diagnosis of cutaneous melanoma. Dermoscopic and videodermoscopic pictures and patient data were analyzed with regard to the pattern: reticular, globular, homogeneous and mixed pattern (two-component pattern; reticular-globular pattern) with central or peripheral globules and multicomponent (mixed – at least 3 types of structures in one nevus).

Results

The reticular pattern was significantly more prevalent in male patients (38.57%, 27 patients) in comparison to female patients (18.45%, 17 patients). We also found a statistically significant lower prevalence of reticular pattern in patients diagnosed with melanomas located on upper limbs. The homogeneous pattern was statistically significantly more prevalent in patients in whom primary tumors were located on the head and upper limbs.

Conclusions

Our study suggests that predominant complex patterns are more commonly observed in patients diagnosed with cutaneous melanoma, although there is a significant number of patients with predominant reticular and homogeneous patterns, which are not often associated with an increased risk of development of melanoma.

Clinical Characteristics in Early Childhood Associated with a Nevus-Prone Phenotype in Adults from Tropical Australia: Two Decades of Follow-Up of the Townsville Preschool Cohort Study

Having numerous melanocytic nevi increases melanoma risk. Few studies have enumerated nevi in children and re-examined them as adults. We aimed to determine if childhood nevus-counts predict nevus-prone adults, and further explore the relevance of host-factors and sun-exposure. Fifty-one Caucasian residents of Townsville (19.16° S, Queensland, Australia) had full-body nevus-counts aged 1–6 and 21–31 years-old. Sun-exposure was determined from questionnaires. Children in the upper-quartile of nevus-counts acquired nevi more rapidly than those in the bottom-quartile (13.3 versus 4.7 nevi/year; p < 0.0005). Children sunburnt before 7 years-old acquired more incident nevi by adulthood (238 versus 126, p = 0.003) particularly if sunburn was severe (321 versus 157.5, p = 0.003) or erythema occurred annually (380 versus 132, p = 0.008). Fair-skinned, freckled children with some nevi ≥ 3 mm, solar lentigines, or a family history of melanoma acquired more incident nevi than children without these attributes. Nevus-prone adults exhibit distinguishing features earlier in life (<7 years-old in Queensland) than has been shown previously. In addition to intervening with sun-protection counselling early enough to reduce risk, being able to reliably triage children into high- and low melanoma-risk groups may inform more efficacious and cost-effective targeted-screening in melanoma-prone populations. Further longitudinal research is needed to confirm that these attributes can reliably separate risk-groups.

Ultraviolet radiation and cutaneous melanoma: a historical perspective

In this article, we summarize the research that eventually led to the classification of the full ultraviolet (UV) radiation spectrum as carcinogenic to humans. We recall the pioneering works that led to the formulation of novel hypotheses on the reasons underlying the increasing burden of melanoma in light-skinned populations. It took long before having compelling evidence on the association between UV and melanoma, in particular, the importance of UV exposure during childhood for both the occurrence of melanoma and death. The role of UVA was established only after 2005. If molecular lesions caused by UV radiation are better known, the precise mechanism by which UV exposure drives melanoma occurrence and progression still needs to be elucidated. More research on the UV-melanoma relationships has led to more evidence-based sun-protection recommendations, especially for children, and to effective control of the artificial UV tanning fashion. Since around 1985-1995, the mortality because of melanoma has started to decrease in younger age groups in most light-skinned populations. If sun protection among children remain on top of public health agendas, there is a fairly great chance that melanoma mortality will stabilize and steadily decrease in all light-skinned populations. The introduction of effective therapies against metastatic disease will improve this reversal in mortality trends.

Childhood sun safety at different ages: relations between parental sun protection behavior towards their child and children's own sun protection behavior

BACKGROUND

Sunburns during childhood are strongly associated with development of melanoma in later life. While parents play an important role in children's sun protection, insight in possible shifts in behavioral responsibility from parents towards their children and the possible effect of children's sex is important for targeting sun safety interventions throughout childhood and adolescence.

METHODS

This cross-sectional survey study was conducted among a representative sample of Dutch parents (N = 1053) of children aged between 4 and 13 years old. Questionnaires measured both parental and children's own sun safety behavior during planned (e.g. going to the beach) and incidental (e.g. bycicling) sun exposure situations. Analyses of variance were used to test for age group differences and linear regression models were computed to detect behavioral shifts in executive behavior.

RESULTS

Parents applied all sun safety behaviors (i.e. sunscreen use, wearing UV-protective clothing and seeking shade) more often on younger children, except for supportive behavior (facilitating children's own sun safety behavior), which remained relatively stable over the years. Older children and girls were more likely to execute sun safety behaviors themselves. A behavioral shift was found in wearing UV-protective clothing during planned situations among 11 year old children. For other behaviors, shifts were predicted after the age of 13.

CONCLUSIONS

Older children execute sun safety behaviors more often than younger children, although they still largely depend on their parents' protection. Specific attention for boys in the primary school years, and for both boys and girls in the years adjacent to adolescence is warranted in skin cancer prevention interventions.

Cutaneous nevi and risk of melanoma death in women and men: A prospective study

BACKGROUND

It was unclear whether an increased number of common nevi (moles) predicts melanoma death.

OBJECTIVE

We prospectively examined the association between number of common nevi and risk of melanoma death.

METHODS

Our study used data from the Nurses' Health Study (n = 77,288 women) and Health Professionals Follow-up Study (n = 32,455 men). In 1986, participants were asked about the number of moles they had with a ≥3-mm diameter on the upper extremity, and we stratified their answers into 3 categories (none, 1-2, or ≥3) on the basis of data distribution.

RESULTS

During follow-up (1986-2012), 2452 melanoma cases were pathologically confirmed; among these, we identified 196 deaths due to melanoma. Increased number of nevi was associated with melanoma death; the hazard ratio (HR) for ≥3 nevi compared with no nevi was 2.49 (95% confidence interval [CI] 1.50-4.12) for women and 3.97 (95% CI 2.54-6.22) for men. Among melanoma cases, increased number of nevi was associated with melanoma death in men (≥3 nevi, HR 1.89, 95% CI 1.17-3.05) but not in women. Similarly, the number of nevi was positively associated with Breslow thickness in men only (Ptrend = .01).

LIMITATIONS

This is an epidemiologic study without examination into mechanisms.

CONCLUSION

Increased number of cutaneous nevi was significantly associated with melanoma death. High nevus count might serve as an independent prognostic factor to predict the risk of melanoma death particularly among male melanoma patients.

Dermoscopic changes in melanocytic nevi covered with both opaque tape and sunscreen cream during narrowband ultraviolet B therapy

Background

Ultraviolet (UV) light may cause dermoscopic changes on melanocytic nevi (MN).

Objectives

To investigate the effects of sunscreen cream (SSc) application on dermoscopic changes in MN during narrowband UVB (NBUVB) therapy.

Methods

Half of the randomly selected MN in each patient were covered with opaque tape and SSc [SSc(+)], and the rest were covered with only opaque tape [SSc(−)] during NBUVB treatment sessions.

Results

More SSc(−) MN displayed dermoscopic changes at end of NBUVB therapy compared to the start of therapy (p=0.035). The number of the MN that decreased in size and showed loss of structure was significantly higher in SSc(−) MN (p=0.04 and p=0.026, respectively).

Conclusions

Sunscreen in combination with opaque tape may contribute to some dermoscopic changes in melanocytic nevi, including decrease in size and loss of structure.

Number and size of acquired melanocytic nevi and affecting risk factors in cases admitted to the dermatology clinic

Introduction

The size and number of acquired melanocytic nevi (AMN) and presence of dysplastic nevi are the leading risk factors that should be recognized in the development of malignant melanoma.

Aim

To evaluate AMN and risk factors in the development of AMN in all age groups admitted to a dermatology outpatient clinic.

Material and methods

Four hundred and twelve patients who were admitted to the dermatology outpatient clinic for any dermatological symptom and who accepted to participate in the study were randomly included in the study. For each case, background-family history and dermatological findings were recorded. All AMN observed in the patients were dermatoscopically examined.

Results

The presence of more than 50 nevi was significantly higher in males, in individuals who had a history of sunburn and smokers. The number of nevi that were 5 mm and below was found to be higher in individuals who regularly sunbathed their face/body, in individuals using sunscreen, in individuals who had a history of sunburn, smokers and alcohol users. The number of nevi that were above 5 mm was higher in smokers. The total dermatoscopy score between 4.75 and 5.45 was found to be higher in individuals who had more than 50 nevi, in individuals exposed to more than one chemical substance and in alcohol users.

Conclusions

When determining the patient’s risk factors, factors such as the patient’s sunbathing habits and chemical substance exposure features should be taken into consideration besides the number and size of nevi.

The burden of cutaneous melanoma and status of preventive measures in Central and South America

RATIONALE AND OBJECTIVE

Very little is known about the burden of cutaneous melanoma in Central and South America, despite the existence of a reasonable amount of population-based data. We present data on melanoma incidence calculated in a standardized way for Central and South America, as well as an overview of primary and secondary prevention issues in the region.

METHODS

Cancer registry data on all incident cases reported in the different registries present in Central and South America were combined to provide registry-based country estimates of age-standardized, sex-specific cutaneous melanoma incidence overall, and by histological subtype and anatomical site. A literature search provided additional information.

RESULTS

Age-standardized incidence rates were between 1 and 5 per 100,000 and tended to be higher further away from the equator. Cutaneous melanomas of the acral type, mostly occurring on the lower limbs, are a distinguishing feature of melanoma in Central and South America in comparison with high-incidence areas. Several preventive measures, both primary and secondary, are in place, albeit largely without evaluation.

CONCLUSION

Due to incomplete registration and different registration practices, reliable and comparable data on melanoma were difficult to obtain; thus it is likely that the true burden of melanoma in Central and South America has been underestimated. The different characteristics of the cutaneous melanoma patient population in terms of anatomical site and histological type distribution imply a need for adapted primary and secondary prevention measures. The generally high ambient ultraviolet radiation levels require sufficient sun protection measures.

Sun protection policies of Australian primary schools in a region of high sun exposure

Queensland, Australia has the highest rates of skin cancer globally. Predetermined criteria were used to score the comprehensiveness of sun protection policies (SPP) of primary schools across Queensland. SPP were sought for schools in 10 regions (latitude range 16.3°S-28.1°S) from 2011 to 2014. Of the 723 schools sampled, 90.9% had a written SPP available publicly. Total SPP scores were low {mean 3.6 [95% CI: 3.4-3.9]; median 2 [interquartile range (IQR) 2, 4]}, with only 3.2% of schools achieving the maximum score of 12. Median SPP scores were higher in Northern and Central Queensland [both 2 (IQR 2, 6) and (IQR 2, 5), respectively] than in Southern Queensland [2 (IQR 2, 3); P = 0.004]. Clothing and hat-wearing were addressed in most policies (96% and 89%) while few schools used their SPP to plan outdoor events (5.2%) or reschedule activities to minimize sun exposure (11.7%). The SunSmart Schools program has been operating in Queensland for 17 years, and while most primary schools now have a written SPP, most are not comprehensive. Incentive-based approaches (5-star-rating award scheme and grants) may assist in addressing this issue, to reduce sun exposure of students and teachers. These data provide a baseline from which improvements in the comprehensiveness of school SPPs can be evaluated.

Neonatal blue light phototherapy increases café-au-lait macules in preschool children

Neonatal blue light phototherapy (NBLP) is an effective treatment for hyperbilirubinaemia. Concerning the influence on melanocytic nevi, conflicting studies have been published. To assess the role of NBLP according to the incidence of melanocytic nevi in preschool children, a cohort of 104 5- to 6-year-old children were included. The case group consisted of 52 NBLP-exposed children, while the control group (n = 52) never had NBLP and was matched regarding age, gender, gestational age and skin phototype. Six dizygotic twins were included with one twin having received NBLP, respectively. The following parameters were recorded: nevi count, presence of freckles, café-au-lait macules, skin phototype and previous history of sun exposure. There was no significant association between nevi count and exposure to NBLP (median nevi count 17.0 compared to 18.5 in controls). No significant difference was also found in the dizygotic twin pairs with a median nevi count of 10.0 (with NBLP) compared to 14.5 (without NBLP). However, a significantly higher prevalence of café-au-lait macules was found in children with NBLP (mean count 0.5) than in children without NBLP (mean count 0.2; p = 0.001). Significant predictors for the number of melanocytic nevi included skin phototype, sun exposure and vacations in the South.

CONCLUSION

In this study, NBLP had no significant influence on the development of melanocytic nevi, but on café-au-lait macules which was a new finding. Differences with comparable studies regarding age, differentiation between nevi and other pigmented lesions as well as dose and type of NBLP need to be taken into account for further investigations.

Changing the risky beliefs of post-partum women about therapeutic sun-exposure

BACKGROUND

Many post-partum women hold risky beliefs about perceived therapeutic benefits of sun-exposure in the post-partum period and infancy.

QUESTION

Can a maternity hospital based educational intervention reduce the prevalence of such beliefs among post-partum women?

METHODS

In this outcome evaluation of an interventional study, two groups of healthy post-partum women (hospital inpatients) were interviewed, 1-4 days following delivery. The first cross-section (106 women) was recruited prior to in-services for maternity staff; the second (203 women) was recruited after completion of the in-services. Data were compared between the groups.

FINDINGS

More pre-intervention than post-intervention women reported they would expose their baby to sunlight to treat suspected jaundice (28.8% vs. 13.3%; p<0.001) or help his/her skin adapt to the sun (10.5% vs. 2.5%; p=0.003); or use sunlight to manage breastfeeding-associated sore/cracked nipples (7.6% vs. 2%; p=0.026).

CONCLUSION

This simple, effective educational intervention could be implemented in programmes for parents, health professionals and students.

Constitutive and relative facultative skin pigmentation among Victorian children including comparison of two visual skin charts for determining constitutive melanin density

Our aim was to examine the association between ethnicity, phenotype, sun behavior and other characteristics, and constitutive and relative facultative skin pigmentation. A total of 191 participants were recruited, with a mean age of 7.6 years (SD 3.4), during 2009-2011 from Maternal and Child Health Centres (MCHC) and schools in Melbourne, Australia. Parental questionnaire data were obtained on sun behavior and examination consisted of noting the child's natural skin, hair and eye color, ethnicity, nevi count and spectrophotometric melanin density (MD). Constitutive skin pigmentation was estimated from buttock MD. Relative facultative skin pigmentation was estimated by hand compared with buttock absorption. Ethnicity, hair color and skin color were associated with constitutive and facultative skin pigmentation on univariate analysis. Higher ambient ultraviolet radiation (UVR) in the past month, greater freckling, greater nevi and increased sun exposure over the past year were related to darker facultative skin pigmentation. Sun exposure over the life course was not. The two skin charts accounted for 39.7% and 21.4% of buttock MD, respectively. Relative facultative skin pigmentation is associated with recent UVR levels, not life-course sun exposure. Relative facultative skin pigmentation may not be a useful measure of sun exposure over the early life course. Skin color charts can be used to assess constitutive skin pigmentation if spectrophotometry is not available.

Patterns and timing of sunlight exposure and risk of basal cell and squamous cell carcinomas of the skin--a case-control study

BACKGROUND

Non-melanoma skin cancer (NMSC), comprised of basal (BCC) and squamous (SCC) cell carcinomas, is the most common cancer in Caucasians. Ultraviolet radiation (UVR) exposure is the most important environmental risk factor for NMSC. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type.

METHODS

A case-control study was conducted among Florida residents to investigate measures of patterns (intermittent vs. continuous) and timing (childhood vs. adulthood) of sunlight exposure in BCC and SCC. Participants included 218 BCC and 169 SCC cases recruited from a university dermatology clinic and 316 controls with no history of skin or other cancers.

RESULTS

A history of blistering sunburn (a measure of intermittent sunlight exposure) was associated with both BCC (OR = 1.96, 95% CI = 1.27-3.03) and SCC (OR = 2.02, 95% CI = 1.22-3.33). Additionally, having a job in the sun for ≥ 3 months for 10 years or longer (a measure of continuous sunlight exposure) was also associated with both BCC and SCC in our study population. With the exception of younger age at first blistering sunburn, measures of younger age at sunlight exposure tended to be associated with SCC, but not BCC risk.

CONCLUSIONS

Results from the current study suggest that sunlight exposure is associated with both BCC and SCC risk regardless of the pattern in which the exposure was received (i.e. intermittent vs. continuous). The data also suggest that sunlight exposure at a younger age may be more important for SCC but not BCC, however additional studies are needed to further characterize sunlight exposure-response relationships in different types of NMSC.

Prevalence of melanocytic nevi in 8- to 10-year-old children in Southern Spain and analysis of associated factors

BACKGROUND

There is a known relationship between melanocytic nevi (MN) and cutaneous melanoma. MN are related to genetic and environmental factors, and the latter appear to be more important in childhood.

OBJECTIVES

To determine the prevalence of MN and its relationship with phenotypic traits and sun exposure habits in 8- to 10-year-old children.

SUBJECTS AND METHODS

We performed a cross-sectional study of 8- to 10-year-old primary school children in the city of Granada (Spain), gathering data on phenotypic traits, sun protection measures, sunburn frequency and the number and density of MN.

RESULTS

We detected a mean of 19.38 MN per child, predominantly <2 mm in diameter. MN count was associated with low phototype, and was higher in boys vs. girls with low phototype. MN were more numerous with higher age. The largest number of MN of all sizes was detected in 10-year-old boys. MN were most frequently located on the torso and other sites intermittently exposed to sunlight.

CONCLUSIONS

A higher MN count is associated with lower phototype (blonde hair and fair skin) and higher age. The mean number of MN, including those of smaller size (<2 mm), was elevated in our series, especially on intermittently exposed sites.

Vitamin D status of adults from tropical Australia determined using two different laboratory assays: implications for public health messages

We measured serum 25 hydroxyvitamin D [25(OH)D] levels of ambulatory adults in tropical Australia to determine whether it is appropriate to continue promoting sun-safety in this population. In August 2006 (winter), self-administered questionnaires were completed by 145 Meals-on-Wheels volunteers (49.3% male; mean age 57.8 ± 14.7 years; 76.6% response) from Townsville, Queensland (Latitude 19(o) S). Serum 25(OH)D was analyzed using two common assays. Mean levels were 68.3 (SD ± 18.7; range 26-142) by DiaSorin Radioimmunoassay and 83.0 (SD ± 30.8; range 30-184) by DiaSorin Liaison® one. No participants were 25(OH)D deficient (<25 nmol L(-1)). Nine participants (6.2%) had 25(OH)D levels between 25 and 50 nmol L(-1) (insufficient), by both methods (seven with a BMI ≥ 25). Twenty-eight participants (19.3%) had one result in the insufficient range and the other in the adequate range. Thus, almost all of these free-living adults in tropical Australia had adequate vitamin D levels at the end of winter. There was poor agreement between the two 25(OH)D assays. These results suggest it is appropriate to continue promoting sun-safe messages to the ambulatory Caucasian adult population of North Queensland, which has an extremely high incidence of skin cancer. The lack of agreement between the two assays is a concern. Few doctors are aware of this measurement issue.

The human health effects of ozone depletion and interactions with climate change

Depletion of the stratospheric ozone layer has led to increased solar UV-B radiation (280-315 nm) at the surface of the Earth. This change is likely to have had an impact on human exposure to UV-B radiation with consequential detrimental and beneficial effects on health, although behavioural changes in society over the past 60 years or so with regard to sun exposure are of considerable importance. The present report concentrates on information published since our previous report in 2007. The adverse effects of UV radiation are primarily on the eye and the skin. While solar UV radiation is a recognised risk factor for some types of cataract and for pterygium, the evidence is less strong, although increasing, for ocular melanoma, and is equivocal at present for age-related macular degeneration. For the skin, the most common harmful outcome is skin cancer, including melanoma and the non-melanoma skin cancers, basal cell carcinoma and squamous cell carcinoma. The incidence of all three of these tumours has risen significantly over the past five decades, particularly in people with fair skin, and is projected to continue to increase, thus posing a significant world-wide health burden. Overexposure to the sun is the major identified environmental risk factor in skin cancer, in association with various genetic risk factors and immune effects. Suppression of some aspects of immunity follows exposure to UV radiation and the consequences of this modulation for the immune control of infectious diseases, for vaccination and for tumours, are additional concerns. In a common sun allergy (polymorphic light eruption), there is an imbalance in the immune response to UV radiation, resulting in a sun-evoked rash. The major health benefit of exposure to solar UV-B radiation is the production of vitamin D. Vitamin D plays a crucial role in bone metabolism and is also implicated in protection against a wide range of diseases. Although there is some evidence supporting protective effects for a range of internal cancers, this is not yet conclusive, but strongest for colorectal cancer, at present. A role for vitamin D in protection against several autoimmune diseases has been studied, with the most convincing results to date for multiple sclerosis. Vitamin D is starting to be assessed for its protective properties against several infectious and coronary diseases. Current methods for protecting the eye and the skin from the adverse effects of solar UV radiation are evaluated, including seeking shade, wearing protective clothing and sunglasses, and using sunscreens. Newer possibilities are considered such as creams that repair UV-induced DNA damage, and substances applied topically to the skin or eaten in the diet that protect against some of the detrimental effects of sun exposure. It is difficult to provide easily understandable public health messages regarding "safe" sun exposure, so that the positive effects of vitamin D production are balanced against the negative effects of excessive exposure. The international response to ozone depletion has included the development and deployment of replacement technologies and chemicals. To date, limited evidence suggests that substitutes for the ozone-depleting substances do not have significant effects on human health. In addition to stratospheric ozone depletion, climate change is predicted to affect human health, and potential interactions between these two parameters are considered. These include altering the risk of developing skin tumours, infectious diseases and various skin diseases, in addition to altering the efficiency by which pathogenic microorganisms are inactivated in the environment.

Parents' attitudes related to melanocytic nevus count in children

Sun exposure, fair phototype, and a high common melanocytic nevus (MN) count have been identified as the most important risk factors for melanoma. MN are mainly acquired during childhood, and their relationship to sun exposure, sunburn, and light skin complexion is well documented. The purpose of this study was to investigate how the sun protection attitudes of parents and their offspring affect MN development in children. We designed a cross-sectional study in 828 9-year-old school children. Trained nurses counted the MN on each child's back and arms, depending on their size. Questionnaires filled by children and parents provided information about sun exposure, attitude towards the sun, and sun-protection behaviors. Multivariate analysis showed that the childhood MN count was linked to fair phenotype--fair skin: rate ratio (RR)=3.80, 95% confidence interval (CI)=2.25-6.41; blue/green eyes: RR=1.2, 95% CI=1.11-1.34; blond hair: RR=1.25, 95% CI=1.10-1.41; history of sunburn: RR=1.13, 95% CI=1.03-1.23, seaside sun exposure--RR=1.14, 95% CI=1.01-1.28, and to their parents' behaviors during exposure to the sun--increase in the number of MN when parents used sunscreen: RR=1.23, 95% CI=1.08-1.40; decrease in MN count when parents wore a tee-shirt: RR=0.86, 95% CI=0.79-0.93. In conclusion, fair phenotype and sun exposure are known major risk factors for MN. Parents' behaviors influence their children and appeared in our analysis as another determinant predictor of MN count, being protective against (wearing a tee-shirt when exposed to sun) or increasing the risk (sunscreen use, reflecting higher sun exposure) for childhood MN development.

Sun-induced changes in stratum corneum function are gender and dose dependent in a Chinese population

Previous studies have demonstrated that UVB radiation changes the epidermal permeability barrier and stratum corneum (SC) hydration. It is well known that sun exposure causes erythema, sunburn and melanoma. However, whether daily sun exposure alters SC integrity and epidermal permeability barrier function is largely unknown, especially in Chinese subjects. In the present study, we assess the SC integrity, SC hydration and epidermal permeability barrier function following various doses of sun exposure. A total of 258 subjects (124 males and 134 females) aged 18-50 years were enrolled. A multifunctional skin physiology monitor (Courage & Khazaka MPA5) was used to measure SC hydration and transepidermal water loss (TEWL) on the forearms. In males, basal TEWL was higher with higher doses of sun exposure than with lower doses and control, whereas in females, basal TEWL was higher with lower doses of sun exposure than with higher doses and control. In the group with higher doses of sun exposure, TEWL in females was significantly lower than that in males. The barrier recovery was faster in females than in males in both control and lower-dose groups. In both males and females, barrier recovery was delayed with higher doses of sun exposure. In males, sun exposure did not alter SC hydration, while in females SC hydration was lower with lower doses of sun exposure as compared with control and higher doses of sun exposure. These results demonstrated that sun-induced changes in SC function and SC hydration vary with gender and the extent of sun exposure.

IGFBP7 is not required for B-RAF-induced melanocyte senescence

Induction of senescence permanently restricts cellular proliferation after oncogenic stimulation thereby acting as a potent barrier to tumor development. The relevant effector proteins may therefore be fundamental to cancer development. A recent study identified IGFBP7 as a secreted factor mediating melanocyte senescence induced by oncogenic B-RAF, which is found commonly in cutaneous nevi. In contrast to the previous report, we demonstrate that B-RAF signaling does not induce IGFBP7 expression, nor the expression of the IGFBP7 targets, BNIP3L, SMARCB1, or PEA15, in human melanocytes or fibroblasts. We also found no correlation between B-RAF mutational status and IGFBP7 protein expression levels in 22 melanoma cell lines, 90 melanomas, and 46 benign nevi. Furthermore, using a lentiviral silencing strategy we show that B-RAF induces senescence in melanocytes and fibroblasts, irrespective of the presence of IGFBP7. Therefore, we conclude that the secreted protein IGFBP7 is dispensable for B-RAF(V600E)-induced senescence in human melanocytes.

Nutritional approach to sun protection: a suggested complement to external strategies

The increasing incidence of skin cancer despite the use of externally applied sun protection strategies, alongside research showing that nutrients reduce photo-oxidative damage, suggest nutritional approaches could play a beneficial role in skin cancer prevention. Penetrating photo-oxidative ultraviolet A radiation reduces skin and blood antioxidants and damages cell components, including DNA. Dietary antioxidant vitamins, minerals, and phytochemicals in addition to n-3 polyunsaturated fatty acids, n-9 monounsaturated fatty acids, and low pro-inflammatory n-6 polyunsaturated fatty acids, have demonstrated protective properties. The presence of these elements in the traditional Greek-style Mediterranean diet may have contributed to the low rates of melanoma in the Mediterranean region despite high levels of solar radiation. This suggests a potentially relevant model for studying dietary/nutritional supplementation for lifelong internal support of sun-protection mechanisms, which could complement external strategies.

Regional variation in infant hypoallergenic formula prescriptions in Australia

There is little information on the regional distribution of food allergy in Australia. We examined the influence of latitude (a marker of sunlight/vitamin D status) on food allergy, as measured by 2007 infant hypoallergenic formula (IHF) prescription rates in children ages 0-2 yrs. Data were compiled from the 52 statistical divisions in mainland Australia plus the island of Tasmania (n=53 observations). Data from the Australian Department of Health and Aging and the Australian Bureau of Statistics were analysed by statistical division. There was significant regional variability in hypoallergenic formula prescription rates (per 100,000 population/yr), with the highest rates in southern Australia (14,406) and the lowest in the north (721), compared with a national average of 4099. Geographical factors (decreasing latitude and increasing longitude) were associated with a higher rate of IHF prescriptions, such that rates were higher in southern vs. northern regions, and in eastern compared with western regions. Controlling for longitude, physician density and markers of socioeconomic status, southern latitudes were associated with higher hypoallergenic formulae prescription rates [beta, -147.98; 95% confidence interval (CI)=-281.83 to -14.14; p=0.03]. Controlling for latitude, physician density and markers of socioeconomic status, eastern longitudes were also associated with higher hypoallergenic formulae prescription rates (beta, 89.69; 95% CI=2.90-176.49; p=0.04). Among young children, hypoallergenic formula prescription rates are more common in the southern and eastern regions of Australia. These data provide support for a possible role of sun exposure/vitamin D status (amongst other potential factors) in the pathogenesis of food allergy.

Regional variation in epinephrine autoinjector prescriptions in Australia: more evidence for the vitamin D-anaphylaxis hypothesis

BACKGROUND

There is little information on the regional distribution of anaphylaxis in Australia.

OBJECTIVE

To examine the influence of latitude (a marker of sunlight/vitamin D status) as a contributor to anaphylaxis in Australia, with a focus on children from birth to the age of 4 years.

METHODS

Epinephrine autoinjector (EpiPen) prescriptions (2006-2007) in 59 statistical divisions and anaphylaxis hospital admission rates (2002-2007) in 10 regions were used as surrogate markers of anaphylaxis.

RESULTS

EpiPen prescription rates (per 100,000 population per year) were higher in children from birth to the age of 4 years (mean, 951) than in the overall population (mean, 324). In an unadjusted model of children from birth to the age of 4 years, decreasing absolute latitude was associated with a decrease in EpiPen prescription rates, such that rates were higher in southern compared with northern regions of Australia (beta, -44.4; 95% confidence interval, -57.0 to -31.8; P < .001). Adjusting for age, sex, ethnicity, indexes of affluence, education, or access to medical care (general, specialist allergy, or pediatric) did not attenuate the finding (beta, -51.9; 95% confidence interval, -71.0 to -32.9; P < .001). Although statistical power was limited, anaphylaxis admission rates (most prominent in children aged 0-4 years) showed a similar south-north gradient, such that admission rates were higher in southern compared with northern regions of Australia.

CONCLUSIONS

EpiPen prescription rates and anaphylaxis admissions are more common in southern regions of Australia. These data provide additional support for a possible role of vitamin D in the pathogenesis of anaphylaxis.

In defense of the sun: An estimate of changes in mortality rates in the United States if mean serum 25-hydroxyvitamin D levels were raised to 45 ng/mL by solar ultraviolet-B irradiance

Emerging scientific evidence strongly supports the beneficial role of vitamin D in reducing the risk of incidence and death from many chronic and infectious diseases. This study estimates increases in melanoma and nonmelanoma skin cancer mortality rates and decreases in chronic and infectious disease mortality rates in the US from the standpoint of approximately doubling population doses of solar UVB to increase mean serum 25-hydroxyvitamin D levels from 16 ng/mL for black Americans and 25 ng/mL for white Americans to 45 ng/mL. The primary benefits are expected to come from reductions in cancer and cardiovascular diseases. Although a few thousand excess deaths per year might occur from melanoma and skin cancer, the avoided premature death rate could be near 400,000/ year, with most of the avoided deaths coming late in life. While oral sources of vitamin D could be used instead of UVB or when UVB irradiance is not available, public health policies do not yet recommend the 3,000-4,000 IU/day required to raise serum 25-hydroxyvitamin D levels to the levels required for optimal health, which would be required before vitamin D fortification levels in food can be raised. Until then, moderate solar UVB irradiance remains an import source, and the health benefits greatly outweigh the risks.