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بسم الله الرحمن الرحيم. Welcome. Pollution & SKIN. By. Dr . Amal Ahmed El - Ashmawy. Lecturer of Dermatology & Venereology. Tanta University. Pollution&Skin. Tanta University. POLLUTION.
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Pollution & SKIN
By Dr . Amal Ahmed El - Ashmawy Lecturer of Dermatology & Venereology Tanta University
Pollution&Skin • Tanta University POLLUTION • Pollution is contamination by a chemical or other agent that renders part of the environment unfit for intended or desired use. • The environment refers to the place where we live.
Pollution&Skin • Tanta University • Natural processes have released toxic chemicals into the environment throughout the history of the earth. • The pollution generated by human activities; presents the most serious problem.
Pollution&Skin • Tanta University Major causes of the pollution
Tanta University Pollution&Skin The harm that can occur to the skin with sufficient exposure will result in the following diseases .
Pollution&Skin • Tanta University Contact Dermatitis Skin Cancers Atopic Dermatitis Chemical Depigmentation Halogen Acne Photosensitive Dermatosis Vibration White Syndrome Connective Tissue Disorders
Pollution&Skin • Tanta University Contact Dermatitis • It is an eczematous eruption caused by external agents Irritant contact dermatitis Allergic skin dermatitis
Tanta University Pollution&Skin Irritant contact dermatitis(ICD) • It is caused by direct damage of the skin by the irritant substance.
Pollution&Skin • Tanta University • ICD is very common with at least 10% of the population suffering from hand dermatitis. • An infant’s skin is more susceptible to irritant damage than adult skin.
Pollution&Skin • Tanta University Irritant Contact Dermatitis
Pollution&Skin • Tanta University Develop If the exposure of the substance or substances is sufficient The skin is particularly susceptible as is found in (AD) patients
Pollution&Skin • Tanta University • The commonest irritants found in the environment are: • Soaps • Detergents • Water • Solvents and • Dry atmosphere.
Pollution&Skin • Tanta University Allergic Skin Reaction • There are two allergic mechanisms that can commonly affect the skin Immediate (IgE) Delayed (cell mediated)
Pollution&Skin • Tanta University Immediate allergic reactions Th2 IL-4 IL-5 C I O B Lymphocytes Plasma cells IgE
Pollution&Skin • Tanta University • The commonest allergenic proteins found in the environment are: • House dust mite • Grasses • Pollens • Natural rubber latex • Dairy products • Peanuts
Pollution&Skin • Tanta University • These allergenic proteins do not penetrate normal skin particularly, but can penetrate damaged skin such as AD and hence aggravate it. • Sometimes exposure to these allergens can lead to anaphylaxis. Peanuts andnatural rubber latex are good examples.
Pollution&Skin • Tanta University • The commonest examples of immediate allergic reaction • Hay fever • Asthma • Contact urticaria
Pollution&Skin • Tanta University Delayed allergic reactions Th 1 IFN-γ IL-2 Allergic Contact Dermatitis (ACD)
Pollution&Skin • Tanta University Allergic Contact Dermatitis
Pollution&Skin • Tanta University • The commonest causes found in the environment are: • Nickel • Rubber • Fragrances • Additives • Plants • Medicaments • Preservatives
Pollution&Skin • Tanta University • The immune system of atopics tends towards Th2 responses and so is less likely to develop ACD even though their exposure to certain delayed allergens will be greater than for non-atopics.
Tanta University Pollution&Skin Atopic Dermatitis • There has been a three-fold increase in patients suffering from AD in the past 30 years. • There is increase in frequency of atopy in industrialized countries. • The reason for this is not clear but the hygiene hypothesis seems to be the best explanation • . It would therefore appear that exposure to pollutants in some way protects against the development of atopy or that the exposure to infectious diseases associated with poorer, protects against atopy
Pollution&Skin • Tanta University Atopic Dermatitis
Pollution&Skin The UVR upon reaching & penetrating the skin can induce certain biological changes. • Tanta University Sunlight & Skin
Pollution&Skin • Tanta University Sunlight (particularly ultraviolet B, and to a lesser degree ultraviolet A radiation) plays an important role in the etiology of the commonest skin disordes.
Pollution&Skin • Tanta University Reaction To UVR Normal Response Abnormal Reaction Ac. reactions • Idiopathic Photo Derm. • Diseases aggravated by sun light. • Abnormal responses due metabolic diseases Ch. reaction • Erythema • Aging • Pigmentation • Pre malignant • & • malignant • ↑Epi. thickness
Pollution&Skin Mainly due to UVB & lesser extent UVA. Due to -Direct effect of UVR on dermal Bl. Vs -UVR affect epidermis → release of vasodilator substances as; prostaglandinώ diffuse into dermis → vasodilatation. • Tanta University Erythema
Pollution&Skin • Tanta University Erythema
Pollution&Skin • Tanta University Pigmentation Immediate Delayed (Suntan) • By UVA &visible light • Very soon after exposure • Photooxidation of • previously formed melanin • By UVB & lesser extent by • UVA & visible light • Formation of new melanin • in the epidermis. • It protects the skin from • further exposure to UVA
Pollution&Skin • Tanta University Pigmentation
Pollution&Skin It starts few days after exposure It related to ↑DNA synthesis & accelerated rate of proliferation of epidermal cells. It provides some protection against further exposure to UVR. • Tanta University Increase Epidermal Thickness
Pollution&Skin • Tanta University Aging Dermal changes Epidermal changes Vascular changes • Irregularly distributed • Some completely absent, • while others are elongated , • tortuous & dilated. • KCs. in ch. exposed skin show • ↓ in life span if compared with • normal one. • These KCs changes are • irregularly distributed; so the • adjacent areas of the epidermis • may be of various thickness • & show uneven pigmentation.
Pollution&Skin • Tanta University Dermal changes Elastic tissue hyperplasia In the sun exposed areas It increases with age
Pollution&Skin • Tanta University Premature Aging
Pollution&Skin • Tanta University • Certain CT disorders are frequently observed in chronic exposed skin Solar Elastosis Colloid Millium
Pollution&Skin • Tanta University Cutis Rhomboidalis Nuchae • The skin is thickened • & yellow • It is divided by well • defined furrows into • an irregular • Rhomboidal network
Pollution&Skin • Tanta University Favre Racouchot Syndrome • The skin is yellow • & thickened and • studded with • numerous comedons • and follicular cysts. • Most common around • orbit & around nose