EFFECTS OF CHEMICALS IRRITANTS AND DRUGS ON SKIN.pptx

chemicals on skin

1. Effects of chemical irritants AND DRUGS to skin PRESENTED BY : MSC/SM/00101/023

2. Definition: Chemical irritants are substances that, upon contact, cause inflammation or irritation to body surfaces like skin, eyes, respiratory tract, or mucous membranes(nose and eyes. May cause permanent damage to skin   Irritation is due partly to activation of mast cells and complement or prostaglandin synthesis that occasionally results in reversible damage to the skin. Such irritation usually occurs within 4 h following topical application of the irritating substance .

3. Irritation, degeneration and necrosis Certain chemicals at sufficient concentration produce an acute irritation, burns among other adverse effects on skin including: erythema, swelling , heat and pain, leukocytosis and increased vascular permeability. Eschar formation, ulceration and necrosis may permanently damage the skin These include strong acids and alkalis and powerful oxidizing and reducing agents are corrosive, caustic and necrotizing chemicals that disrupt the cornified layer, damage cell membrane and produce cytotoxicity directly, and stimulate release of pro-inflammatory cytokines . More common is chronic cumulative irritation from repeated exposures to mild irritants such as soaps, detergents, solvents, and cutting oils. Damage may be temporary or permanent Effects may be Direct to the skin, systemic effects or combined

4. Direct Effects (Local Reactions) Irritation : redness, itching, burning, and inflammation, Blisters or Wheals: Defatting/Drying : certain solvents or detergents, can strip the skin of its natural oils, leading to dryness and cracking

5. Corrosion/Burns : cause severe tissue damage  or Eating away of skin- may be due to strong acids and bases Changes in Pigmentation : permanent changes in skin color, either darkening or lightening specific areas; tar , asphalt products, and some disinfectants Melanin production: increased or decreased production. Chemicals can a ccumulate in dermal macrophages, causing visible pigmentation. Aryl hydrocarbon receptor (AHR): Dioxins and dioxin-like compounds can activate AHR, which is involved in keratinization and melanogenesis , leading to chloracne and hyperpigmentation .

6. Chloracne : acne-like lesions caused by exposure to halogenated aromatic compounds, notably dioxins, and is a hallmark of systemic toxicity. It manifests as comedones , cysts, and nodules, and can lead to open sores and scarring in severe cases. Exposure to Agent Orang e , a herbicide used during the Vietnam War, can lead to various skin conditions, most notably chloracne , a rare skin eruption characterized by blackheads, cysts, and nodules, and potentially other skin diseases and cancer s.

7. Toxic epidermal necrolysis (TEN) is one of the most immediate life-threatening skin diseases caused by chemicals or drugs. Characterized by a sudden onset of large, red, tender areas involving a large percentage of the total body surface area. As the disease progresses, necrosis of the epidermis with widespread detachment occurs at the affected areas. Once the epidermis is lost, only the dermis remains, severely compromising the ability of the skin to regulate temperature, fluid, and electrolyte homeostasis. Since the epidermis is lost, the remaining dermis posses little resistance to chemicals entering the systemic circulation and to infection from microorganisms.

8. Hyperpigmentation is well known to result from exposure to phototoxic agents including coal tar, coumarin derivatives found in perfumes and certain food such as limes and food plants ( parsely , celery), dyes in cosmetics, and elements such aslead , bismuth,and arsenic, smoking etc

9. Skin Cancer : arsenic, coal tar, soot, creosote, petroleum products, and some industrial chemicals, can increase the risk of developing skin cancer, particularly non-melanoma types.

10. Cutaneous Drug Reactions Drug acts as a hapten and binds to proteins. Most are immune mediated hypersensitivity reactions , classified as Immediate reactions. Immune complex-dependent reactions. Delayed hypersensitivity reactions. Non immunologic mechanisms Pigmentary changes related to accumulation in dermis of amiodarone , anti- malarials , minocycline, quinolones. Alteration of hair follicles by antimetabolites. Lipodystrophy associated with metabolic effects. Type I : IgE mediated, menifests as urticaria , angio-oedema and anaphylaxis- caused by proteins -insulin . Type II: Cytotoxic reaction produces haemolysis and purpura. Caused by penicillin , cephalosporins , sulfonamides and rifampin. Type III: is immune complex reactions, result in vasculitis, serum sickness and urticaria . Caused by salicylates, chlorpromazine and sulfonamides. Type IV: Delayed-type reactions, cell-mediated hypersensitivity, result in contact dermatitis , exanthematous reactions and photoallergic reactions. Most common , It is not dose-dependent. Begin usually one to three weeks after medication is started. There may be eosinophilia and may recur if chemically related drugs are used. Immediate reactions include Type I and Type II.

11. Warfarin induced necrosis of skin : Rare devastating effect of warfarin therapy, consequence of occlusive thrombi in vessels of the skin and subcutaneous tissue, and typically begins three to five days after therapy is initiated Maculopapular eruptions ( Morbilliform ): starts on Trunk and Intertriginous areas. Erythematous macules and papules, frequently symmetric and may become confluent

12. Exacerbation or induction of dermatologic disease Photosensitivity eruptions : abnormal reaction of the skin to light, particularly ultraviolet (UV) radiation. Pigmentation changes . Drug induced hair disorders Hair loss Hirsutism: excessive hair growth in females in androgen-dependent areas (face , chest , back)   Hypertrichosis : excessive hair growth anywhere on the body, in both sexes. Drug induced nail disorders Onycholysis:nail plate separation Onychomadesis : nail plate shedding Paronychia: nail fold infection Nail discoloration: caused by various factors, including infections, trauma, and systemic conditions Pruritus : sensation that provokes the desire to scratch.

13. Urticaria / Angioedema : pruritic red wheals of varying size. Angioedema is deep dermal and subcutaneous edema, may involve respiratory and GI mucous membranes . Hypersensitivity syndromes : Initially presents with a morbilliform eruption, indistinguishable from less serious reactions and eventually develop into erythematous follicular papules , pustules, bullae, or purpura. Fixed Drug Eruptions : One or more sharply demarcated, erythematous lesions leading to blister formation. Hyperpigmentation after resolution Pustular Eruptions : Acute generalised exanthematous pustulosis (AGEP) : acute onset fever , generalised scarlatiniform erythema, small, sterile, non-follicular pustules . Vasculitis : Often present as palpable purpuric lesions, limited to lower extremities or other dependent areas. May involve other organs

14. Stevens-Johnson Syndrome Widely distributed purpuric macules and blisters and prominent involvement of the trunk and face are likely to have Stevens-Johnson syndrome, which is usually drug-induced Drugs implicated : Sulfonamides, nevirapine , allopurinol, lamotrigine , aromatic anticonvulsants, and oxicam NSAIDs . Stevens-Johnson syndrome is characterized by sloughing of less than 10 % of the epidermis Toxic Epidermal Necrolysis(TEN) is characterized by sloughing of more than 30 % of the epidermis

15. Injection Drug Use Effects on Your Skin : Injection drug use with stimulants such as cocaine and methamphetamine and opioids like heroin can cause various skin issues injection mark-“track marks”:caused by post-inflammatory hyperpigmentation that can occur from repeated use skin and soft-tissue infections, such as abscesses and cellulitis, a deep bacterial infection of the skin wound botulism, a rare but serious and potentially life-threatening illness; Inject illicit drugs under your skin or muscles ("skin popping") /(" muscle popping" or "muscling")-Clostridium botulinum-makes a toxin that attacks the body’s nerves, which can make it difficult to breathe, weaken muscles, even cause death Smoking crack cocaine is associated with burns and eyebrow thinning methamphetamine use can precipitate slowed wound healing and suppressed immune function, which can exacerbate the susceptibility to Staphylococcus aureus, a bacterial infection .

16. Alcohol use may cause: Spider angiomas , which are caused by dilated blood vessels under the surface of the skin and resemble a red to purplish spider. These often appear on the hands, upper chest, neck, and face. Jaundice, which can make the whites of the eyes yellow or give the skin a yellowish tint. Bruising easily . Steps to help prevent health problems from chemical exposure to the skin : Recognize the hazard be aware of how your skin can be exposed to chemicals Manage the risk Reduce exposure and prevent injury: Direct contact with liquid, including spills and splashes; Contact with contaminated surfaces; Contact with spray or mist

17. Systemic Effects (Absorption and Beyond)

18. Chemicals may be absorbed into the Body through the skin into the bloodstream, potentially affecting other organs and systems. Paints and coatings contain solvents (such as toluene and xylene), which can cause liver and kidney damage Immune System : certain chemicals can enter the system and weaken the immune system. A ctivate immune cells in the skin, such as Langerhans cells, which process and present antigens to other immune cells, initiating an immune response.  Nervous System : Some neurotoxins absorbed by skin lead to neurological problems by disrupting communication between neurons, or damage nerve cells.  Eg organophosphates; Some chemicals found in hair and skin products and heavy metals- lead , manganese Respiratory System : causing irritation or inflammation. Isocyanates found in paints and building materials, can cause airway sensitization when they come into contact with the skin-leading to allergic reaction or asthma attacks Endocrine System Disruption : Certain chemicals, like parabens and phthalates, can disrupt the endocrine system, potentially leading to reproductive problems and other health issues.

19. Sensitization: Allergic Contact Dermatitis Allergic contact dermatitis is an allergic response caused when certain chemicals contact the skin. For example, epoxy resins, chromates, rubber chemicals, amine hardeners, and phenol-formaldehyde resins may cause allergic contact dermatitis Airway Sensitization : allergic reaction of the mucous membranes or airways may result when certain chemicals are inhaled or are exposed to the skin. For example, skin exposures to isocyanates (contained in many paints and other building materials, like spray-on insulation and roofing materials) can result in airway sensitization. Combined Effects Chemical exposure to the skin may cause multiple health problems. For example, individuals working with cement may experience combined health problems. Contact with the cement may result in direct irritation at the point of contact from the ability of the cement to dry out the skin. Workers may also become sensitized to cement due to the chrome salts present in the material.

20. Common Irritants and Sensitizers Soaps and Detergents Solvents: paints and cleaning products, varnishes , and nail polish remover. Oils and Cutting Fluids : Oils used in machinery or cutting fluids can cause skin irritation and dermatitis. Perfumes and Fragrances : allergic reactions or skin irritation. Cement dust can cause skin irritation and dermatitis. Pesticides and Fertilizers: organophosphates Preservatives: Certain preservatives in cosmetics and toiletries can also be irritants or sensitizers; isothiazolinones

21. Metals: Nickel , often found in jewelry, clothing fasteners, and other items, is a common allergen that can cause contact dermatitis. Body fluids: Urine and saliva can cause irritation to the skin. Topical Medications: Some topical medications, like retinoids and benzoyl peroxide, can cause irritant contact dermatitis with long-term use. Antiseptics and Antibacterials : Acids and Alkalis Plants : poison ivy, poison oak, poison sumac, wood/stinging nettles, and certain herbs like chamomile and ragweed. can cause contact dermatitis.

22. Common chemical substances used in skincare Active Ingredients for Skin: Retinoids (like Retinol): derivatives of vitamin A, known for their anti-aging and acne-fighting properties, promoting cell turnover and collagen production. Vitamin C: antioxidant that helps brighten the skin, reduce hyperpigmentation, and protect against free radical damage Alpha Hydroxy Acids (AHAs): like glycolic acid, are used for exfoliation, improving skin texture and reducing the appearance of fine lines and wrinkles Salicylic Acid : A beta hydroxy acid (BHA) that is effective for treating acne and blackheads, as it can penetrate deep into pores. Hyaluronic Acid : A humectant that attracts and binds water to the skin, providing hydration and plumping the skin. Niacinamide - a form of vitamin B3: acne, hyperpigmentation, and redness Vitamin B5-panthenol : Acting as both a humectant and emollient; used as a hydrating and moisturizing ingredient

23. Toluene : Used in nail polish and fragrances, but has raised concerns about potential health effects. Coal Tar : Used in some treatments for psoriasis and dandruff, but is a known carcinogen. Polyethylene Glycol (PEG): Used to thicken products and help replenish the moisture barrier. Hydroquinone : skin-brightening agent or depigmentation used to treat skin discoloration (dyschromia), such as hyperpigmentation, freckles, melasma , solar lentigines , and chloasma . Hydroquinone can inhibit the conversion of L-3,4-dihydroxyphenylalanine (L-DOPA) into melanin, helping to lighten the skins ; but has been linked to health concerns Vitamin E - antioxidant: protect skin from damage, hydrate, and potentially reduce signs of aging. Sunscreen- Oxybenzone : chemical compounds to filter out harmful UV rays from the sun. Sulfates : These are cleansing agents that can strip the skin's natural oils. Phthalates : These are chemicals that soften skin and dissolve certain ingredients, but some studies indicate they can have adverse health effect

24. Some chemical medications Hydrocortisone Cream (1%): soothe inflammation and itching in eczema , contact dermatitis, and insect bites. Calamine Lotion : for contact dermatitis, such as poison ivy or oak rashes, as it can reduce itching and dry out blister-like rashes. Zinc Oxide Ointm ent: soothing to irritated skin. Emollients : moisturizing treatments applied directly to the skin to reduce water loss and cover it with a protective film, often used for managing dry or scaly skin conditions. Oral Antihistamines : like diphenhydramine (Benadryl) or loratadine (Claritin), can help reduce itching and symptoms associated with allergic reactions. Topical Antihistamines : These are available as creams, ointments, and sprays and may help relieve itching and reduce inflammation caused by contact allergens.

25. Preservatives : Parabens: These are commonly used as preservatives in skincare products to prevent bacterial growth and extend shelf life. Formaldehyde : While it can reduce bacterial growth, formaldehyde is also considered a human carcinogen and should be avoided. Fragrance : Many fragrances are used in skincare products to give them a pleasant aroma, but some can cause allergic reactions . THE END