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

Inflammation – allergic or non-allergic

Mucous membranes

– Eyes itching, red, edema, secretion

– Nose edema, secretion, sneezing

– Airways edema, secretion, constriction (asthma)

Skin eczema, nettle rash

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 allergen Low molecular

Often protein mw 5-100 kD chemical

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

IgE- mediated reactions

Skin prick test

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

Allergic contact eczema

Delayed, cell mediated reaction

–Nickel, chrome, cobalt

–Rubber chemicals

–Pharmaceutical drugs, cosmetics (Kathon)

–Colophony, perfume, plants

–“Chemicals” R-phrase 43

Epoxy, acrylates, resins, plastic chemicals, organic dyes, amines etc.

Patch test

Irritative eczema

Trigger factors

Chemical irritation

Mechanical irritation

Heat, perspiration

“Dry skin”

Infection?

Stress

Climate factors (e g time of year)

Accident with 4 liters acetic acid in room ca 12 m2

Asthma after accident

Exposure Fraction with asthma

Percent with asthma

Low 0/6 0

Mean 4/21 19

High 4/9 44

Follow up of 51 persons, 36 previously without airway disease, exposure was estimated.

Substance CAS-nr Year Occupationalexposure limit (8 hour)

Occupationalexposure limit(15 min)

ppm mg/m3 ppm mg/m3

Acetic acid 64-19-7 1990 5 20 10 25

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)

HarmfulAcut toxicity (oral, dermal, inhalation)Skin irritationEye irritationSkin sensitisationSpecific organ toxicity – single exposureAirway irritationNarcotic 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 hazardRespiratory sensitisation Germ cell mutagenicity CarcinogenicityReproductive toxicitySpecific 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.