study guide need by tomorrow afternoon

1

 Protective mechanisms of the respiratory tract

 Removal of large particles in the nasopharyngeal

region

 Bifurcation of respiratory tract

 Cough reflex

 Mucociliary elevator

 Macrophages

 Aerodynamic diameter

 Classes of airborne hazards

 Gases and vapors

 Particulates

 Oxygen-deficient atmosphere

 Size-selective sampling

 Inhalable fraction

 Thoracic fraction

 Respirable fraction

 Pneumoconiosis

 Silicosis

 Asbestosis

 Coal worker’s pneumoconiosis

 Byssinosis

 PEL for silica

 Amorphous silica

 Crystalline silica

EHST 3700/3701:

Industrial Hygiene

 To recognize the basic structure and functions of the human respiratory tract

 To list the major classifications of airborne hazards

 To identify airborne hazards and their source processes

 To describe occupational diseases associated with exposure to airborne contaminants

 To understand how spirometry is used to evaluate lung function and detect patterns of lung damage

 To recognize situations where oxygen-deficient atmospheres might exist

 To explain the difference between simple and chemical asphyxiants

 To explain the mechanisms leading to hypoxia

 Anatomy and function of the respiratory

system

 Airborne hazardous materials

 Occupational diseases associated with

airborne particulates

 Oxygen-deficient atmospheres

 May be inhaled either as fumes or dusts

 Metal oxides – metal atoms combined with

oxygen atoms (i.e. iron oxide or rust)

 Metal fume fever

 Due to inhalation of metal fumes during

welding

 Associated with a set of

symptoms mistaken for

flu

 Characterized by fever,

nausea, coughing and

wheezing, muscle

aches

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Metal Organs/Systems Affected Metal Organs/Systems Affected

Aluminum Nervous system,

respiratory tract

Iron Nervous system, liver,

gastrointestinal tract,

respiratory tract,

hematopoietic system

Beryllium Respiratory tract, skin Lead Kidneys, nervous system,

gastrointestinal tract,

hematopoietic system, skin,

reproductive system

Cadmium Kidneys, nervous system,

gastrointestinal tract,

respiratory tract, bones,

heart

Mercury Kidneys, nervous system,

gastrointestinal tract,

respiratory tract

Chromium Kidneys, nervous system,

liver, respiratory tract,

skin, teeth

Nickel Nervous system, respiratory

tract, skin

Copper Gastrointestinal tract,

hematopoietic system

Thallium Kidneys, nervous system, liver,

gastrointestinal tract,

respiratory tract

 Fumes are inhaled during smelting and

refining of aluminum

 Used in making paints and coatings,

ammunition and explosives, abrasives,

ceramics

 Eye deposition – corneal damage

 Inhalation of aluminum oxides

 Acute exposure: alveolar edema

 Chronic exposure: Shaver’s disease or

bauxite lung

 OSHA PEL = 15 mg/m3 (total); 5 mg/m3 (resp)

 NIOSH REL = 10 mg/m3 (total); 5 mg/m3 (resp)

 ACGIH TLV (2010) =

1 mg/m3 (resp)

 Worker exposure to lead fume or dust

(lead oxide)

 Processes: lead mining and smelting,

cutting and welding on surface with lead,

manufacture or recycling of lead-

containing batteries, production of lead-

containing paint

 Legislation requiring identification of

lead-based paint in residential buildings

 Lead removal workers

 People living in the buildings (children)

 Lead accumulation

 90% lead  bones  10-20 years

 10% lead  liver and kidneys  months

 Symptoms of lead toxicity

 Muscle weakness

 Insomnia

 Lassitude

 Weight loss

 Colic

 Constipation

 Headache

 Memory loss

 Anemia

 Irritability

 Paralysis of extensor muscle

in the wrist

 Lead line

 29 CFR 1910.1025 (General industry)

 29 CFR 1926.69 (Construction industry)

 Action level = 35 ug/m3

 Employee training on lead hazards and

protection methods

 Shower and change rooms

 Air monitoring for lead

 Provision of control measures

(engineering, PPE)

 Medical surveillance (lead in blood)

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 Present in lead and zinc ores

 Uses: alloys, electroplating, pigments,

corrosion-resistant coatings, batteries,

fungicides

 Occupations at risk:

 Smelter workers

 Electroplating workers

 Welding or soldering workers

 Blood  liver  kidneys (20 years)

 29 CFR 1910.1027

 Acute exposure

 Coughing

 Chest pain

 Metallic taste in

mouth

 Chronic exposure

 Anemia

 Liver and kidney

damage

 Emphysema

 Heart damage

 Processes: smelting, roasting and extraction

of chromate from ore, chemical and

refractory processing, manufacture of alloys

containing lead

 Hexavalent chromium

 Acute exposure

 Coughing

 Wheezing

 Headache

 Difficulty and

pain in breathing

 Fever

 Weight loss

 Chronic

 Lung cancer

 Liver damage

 Kidney damage

 An occupational respiratory disease caused

by the inhalation of cotton dust or dusts from

other vegetable fibers such as flax, hemp, or

sisal

 A chronic, asthma-like narrowing of airways

 Bysinossis – exposure to

cotton, linen, hemp,

flax

 Allergic alveolitis –

exposure to spores from

fungi and molds

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 Obstructive pattern

 Damage to the small airways or bronchioles

 Results to decreased ability to exhale air

 Evaluated using expiratory volume (air that

can be exhaled)

 Example: coal worker’s pneumoconiosis

 Restrictive pattern

 Reduction in the volume of air taken in and

then pushed out of the lungs

 Evaluated using vital capacity (VC)

 Due to formation of fibrotic lesions

 Used to evaluate lung function

 Involves exhaling into a tube attached to a

machine that measures the volume of air

passing through the tube

 Normal atmospheric oxygen = 21%

 Oxygen-deficient < 19.5%

 Symptoms: dizziness, uncoordination,

unconsciousness

 End result: Permanent brain damage or

death

 Found in confined spaces

 Oxygen-enriched > 23%

 Can pose fire or explosion hazards

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 Confined spaces (tanks, tunnels, etc)

 Interiors of metal tanks which have oxidized

inside

 Enclosed areas containing inert gases, simple

and chemical asphyxiants

 Use of evaporative cleaning solvents in tanks

 Welding or cutting inside of tanks or other

confined spaces

 Decomposition of vegetation or other organic

matter

 Processes that use or generate chemical or

simple asphyxiants

 Interfere with the body’s absorption of

oxygen from the surrounding air

 Simple asphyxiants

 Displace air and the oxygen it contains

 Chemical asphyxiants

 Interfere with absorption or utilization of oxygen

through reactions on a molecular level

 Health effect

 Hypoxia – condition within the body in which an

inadequate amount of oxygen is available to the

tissues

 Carbon monoxide (CO)

 Interferes with the functioning of hemoglobin

by competing with oxygen for binding to the

heme groups

 Hemoglobin

 Has a much higher affinity (200x) for CO than O2

 Result: Carboxyhemoglobin

CO O2

Canaries were

used by miners

as “living

oxygen

meters”.

 Hydrogen cyanide

 Changes iron present in hemoglobin from a

ferrous state (Fe2+) to a ferric state (Fe3+)

 Result: methemoglobin  methemoglobinemia

 Metals with occupational exposure

significance include aluminum, lead,

chromium and cadmium.

 Lung function is evaluated using spirometry,

which is used to measure specific volumes of

inhaled or exhaled air. Patterns may be

obstructive or restrictive.

 Hypoxia is produced either by simple and

chemical asphyxiants, which displaces air

and interfere with hemoglobin, respectively.