Presentation on theme: "Mathias Holm, M. D., PhD Occupational and Environmental Medicine (Arbets- och miljömedicin) Sahlgrenska academy and University Hospital 2013-03-21 Asthma,"— Presentation transcript:
Mathias Holm, M. D., PhD Occupational and Environmental Medicine (Arbets- och miljömedicin) Sahlgrenska academy and University Hospital 2013-03-21 Asthma, allergy and laboratory work
Allergy Reaction in the immune system. Specificity, “memory”, host factors of importance. Reactions in mucous membranes mediated by immunoglobuline E (IgE, type I). Eczema by cells (type IV), nettle rash by IgE.
Non-allergic reactions Hypersensitivity Other specific immunologic mechanism (not type I or IV)? Other, non-immunologic mechanism?? Irritation Non-specific mechanism –No specificity, no memory? –Host factors important, variable sensitivity Corrosion Very strong irritation, irreversible tissue damage.
Allergen in IgE-mediated reactions High molecular allergenLow molecular Often protein mw 5-100 kDchemical Hapten Human protein
What causes allergy? IgE-mediated reactions High molecular agents –Pollen, furred animals, mites –Plants, fish and shellfish, enzymes, latex, lab animals, insects Low molecular agents (also other mechanisms) –Diisocyanats, acid-anhydrids, cyanoacrylate, some amines, glutaraldehyde, persulfates
High molecular agents can cause asthma, rhinitis
Low molecular agents can cause asthma, rhinitis
Symptoms from airways by irritants - vapour, gas, dust, fumes
Irritation/corrosion on skin and eyes and airway irritation Irritation and corrosion - localised effects at the place of contact between the agent and the skin, eyes or airway mucous membrane. Corrosive substances may destroy tissues at first contact. Irritating substances are non-corrosive substances that may cause inflammation in tissues at first contact.
Irritating chemicals - irritation in airways. Irritation – reversible changes (usually – obs! asthma). Also toxic effects (interaction with autonomic nervous system) leading to reflexes (sneezes, cough, etc). These effects are reversible. Irritation/corrosion on skin and eyes and airway irritation
Extract from CLP-regulation H332 Harmful if inhaled (skadligt vid inandning) H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled (kan orsaka allergi- eller astmasymtom eller andningssvårigheter vid inandning) H335 May cause respiratory irritation (kan orsaka irritation i luftvägarna)
Harmful Acut toxicity (oral, dermal, inhalation) Skin irritation Eye irritation Skin sensitisation Specific organ toxicity – single exposure Airway irritation Narcotic effects Product is harmful by inhalation, skin contact or ingestion. Also used for products causing allergy at skin contact, irritating skin, eyes or airways or having narcotic effects.
Health hazard Respiratory sensitisation Germ cell mutagenicity Carcinogenicity Reproductive toxicity Specific Target Organ Toxicity — Single exposure, Specific Target Organ Toxicity — Repeated exposure Aspiration hazard Product may cause hereditary genetic damage, cancer, be teratogenic or impair reproduction. Also used for products causing allergy when inhaled, chemical pneumonitis at ingestion or other serious damages at single or repeated exposure.