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Chemicals. Forms. Chemical health hazards may be divided into the following categories: Toxic, including carcinogenic; Corrosive & irritant; Dermatitic/sensitising. Forms. Chemical hazards can also be classified according to physical state: Liquids (fluids) Dusts (solid particles)
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Forms • Chemical health hazards may be divided into the following categories: • Toxic, including carcinogenic; • Corrosive & irritant; • Dermatitic/sensitising
Forms • Chemical hazards can also be classified according to physical state: • Liquids (fluids) • Dusts (solid particles) • Fumes (fine solids, often metallic) • Mists (finely suspended droplets) • Vapours (gaseous form of a solid or liquid)
CHIP • Classify substance (Approved supply list) • Assign categories of danger & risk phrases • Provide safety data sheet • Label • Safe packaging • Child-resistant closures • Tactile danger warnings • Mention hazards in advertisements
Health Effects of Hazardous Substances • Under CHIP, suppliers must classify dangerous chemicals under one or more of the following: • Very toxic • Toxic • Harmful • Corrosive • Irritant • Sensitising • Carcinogenic • Mutagenic • Toxic for reproduction
Composition and/or ingredients Hazards First aid Fire fighting Accidental release Handling & storage Exposure controls Personal protection Physical & chemical properties Stability & reactivity Toxicological info Ecological info Disposal Transport Regulatory & other info Safety Data Sheets
Lead • Most dangerous as a fume or dust • Target organs: • Central nervous system • Gastrointestinal tract • Blood & blood-forming organs • Muscles of wrist or foot • Gums • Symptoms affect gastrointestinal tract, nervous system and blood
Mercury • Target organs: • Central nervous system & brain • Kidneys • Symptoms affect central nervous system with personality changes • Workers at risk: • Dentistry • Thermometers, barometers, electrical switchgear
Benzene • Volatile liquid absorbed by inhalation and skin contact • Target organs: • Central nervous system • Blood-forming organs • Symptoms are narcosis, anaemia and leukaemia
Phenol • Corrosive & toxic substance absorbed by the skin • Systemic toxin affecting central nervous system • Symptoms affect central nervous system, liver and kidneys
Trichloroethylene • Harmful by inhalation, prolonged skin contact & ingestion • Affects central nervous system, skin and respiratory tract • May be an animal carcinogen
Siliceous Dust • Inhalation of dust causes fibrosis of lungs • Symptoms caused by reduced lung function, breathlessness, heart strain and possibly death
Asbestos • Inhalation of dust causes fibrosis of lungs • Symptoms caused by reduced lung function, breathlessness, heart strain & possibly death • Risk of lung cancer in fibrotic regions
Carbon Monoxide • Invisible gas absorbed by lungs into blood stream, combining with haemoglobin and inhibiting oxygen transport • Oxygen starvation causes loss of consciousness
Carcinogens • Produce malignant tumours by affecting cell functioning • Long latency period and no threshold of harm • Examples: • Tars (skin cancer) • Asbestos (lung cancer & mesothelioma) • Vinyl Chloride Monomer (angiosarcoma)
Corrosive Substances • Acids destroy living tissue and cause severe burns; examples include nitric and sulphuric acid • Ammonia is a corrosive alkaline gas, soluble in water, which can cause severe burns by liquid contact or inhalation
Dermatitic Hazards • Dermatitis: non-infectious inflammatory condition of the skin caused by contact with chemical, physical or biological agents • Classified into two forms: • Contact: caused by contact with primary cutaneous irritants (greases, mineral oils, solvents); • Sensitisation: Caused by cutaneous sensitisers (rubber additives, nickel compunds, hardwood dust)
Sensitisers • Chemical agents able to produce an allergic reaction in certain individuals • Production of antibodies triggers an allergic reaction each time person is subsequently exposed to very small quantities of the causative agent
Sensitisers • Respiratory System: • Results in asthma • 2 principle types of agent: • Antigens, such as flour, grain & shellfish protein • Substances such as isocyanates and platinum salts • Skin: • Results in dermatitis • Skin reaction will occur whenever there is further contact with sensitising agent (common sensitising agents are isocyanates)
Sensitisers • Chemical agents able to produce an allergic reaction in certain individuals • Production of antibodies triggers an allergic reaction each time person is subsequently exposed to very small quantities of the causative agent