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Screening and Monitoring in Occupational Health and Safety
OCT 420 HC
SKIN
By Kylie Stitt and David Freeman
Lecturer: Dr J. Cromie
Latrobe UniversitySchool of Occupational Therapy
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Introduction
Occupational skin disease can be induced by, or aggravated by
exposure to irritant agents in the work environment. Although most
occupational skin diseases are not life threatening, they can cause
considerable discomfort to the employee. This can have an effect
on productivity, employee and team moral as well as business
operations.
It is important to recognise the effects of occupational skin disease
with respect to short and long term effects. Occupational health
and safety professionals should be aware of the types, and causes
of occupational skin disease as well as preventive measures.
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Anatomy of Skin
Epidermis
- superficial layer
- epithelium cells
- varying thickness depending on site
- hair shaft
Dermis
- deep layer
- connective tissue
- blood vessels
- lymphatic vessels
- nerves
- hair shaft
- nails
Superficial Fascia
- layer below the dermis
- hair follicle
- sweat glands
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Snell (1986)
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Function of Skin
Protective barrier
- a protective layer of natural oils to retard moisture evaporation
and to act as a mechanical shield.
Goh (1994)
Burns
- depth indicates rate of healing and methods of treatment
Partial thickness- heal from cells of hair follicle, sebaceous glands,
sweat glands, and cells of the edge of the burn
Full thickness - deeper than sweat glands will heal slowly from
the edges of the burn only
- require skin grafting to prevent contracture and
increase the rate of healing
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Skin grafting
Split thickness - removal of epidermis from donor site and
positioning graft on burn site
Full thickness - involves both the epidermis and the dermis, with
the provision of circulation supply at the burn site
and within the donor graft to survive.
Snell (1986)
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Types of Occupational Skin Disease
Occupational Dermatitis
- Eczema and dermatitis- inflammation of the skin
- Contact dermatitis refers to an inflammation that is caused
by an external agent
- Most commonly these diseases are localised to the hands
and forearms and can prevent a person from continuing
employment
- Occupational dermatitis can be caused by a variety of
interactions in the workplace
- Many substances encountered in the occupational
environment can affect the skin in different ways and
cause different types of reactions
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CHEMICALIrritant Absolute, Immediate first contact inflammatory reaction
of the skin – strong bases and acids (potassium chloride, ethylene oxide)
Marginal Repeat contact (Kerosene, various cutting fluids)Allergens Contact causing a reaction (epoxy resins, chemicals
used in making of rubbers, chromates, nickel)MECHANICALFriction Calluses, abrasions, lichenification of skin (violinist
neck, knuckle pads of carpet layers), Koebner’s phenomenon (development of lesions of psoriasis or lichens planus, in workers predisposed to having either of these skin disorders in traumatised areas of skin)
Pressure Blisters, nail dystrophyVibration Vibration induced white fingers, Raynaud’s Disease
(certain types of vibrating equipment)PHYSICALHeat Burns, sweating (Miliaria, intertriginous rashes)Cold Frostbite, Raynaud’s symptomsRadiation Radiation dermatitis, skin cancers (x-ray exposure),
photosensitivity eruptions, phytophotodermatitis (eruptions form contact with plants containing furocoumarin in presence of light.
BIOLOGICALPlants Poison Ivy, oak and sumac (forest fire fighters)Insects Lyme disease from bite of tick in forester)Animal Orf (viral eruption from infected sheep)Microbiological Agents
Viruses- herpetic whitlow (herpes simplex of finger in dentists)Bacterial- anthrax (contact with spores in contaminated goat hair)Fungal- Mycobacterium Marinum (fish tank cleaners)Rickettsial- Rocky Mountain spotted fever (tick bite in dog handler)Protozoa- Plazmodium (causing malaria from mosquito bite in laboratory workers)Helminthes- Ancylostoma braziliense (causing cutaneous larva margins, skin eruptions in workers who
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are exposed to organisms from infected soil)Table 1 from Mc Cunney (1994) ch.17 p.
Irritant Reaction
Cause pathological reactions in the skin with
exposure in sufficiently high concentrations and
length of time
Reactions to irritants can vary greatly between
individuals
Some irritants give no visible change on one or two
contacts, but can still reduce the defence mechanism
of skin
Contact Allergy
Involves an altered type of reaction in the skin
The allergy as such does not cause any visible alteration, but
the skin can develop dermatitis when it comes into contact
with the allergens (sensitisers) to which the allergy has been
acquired
The origin of contact allergies can occur after one week of
exposure or years and even decades
The allergy is very specific and involves one or a few very
similar definitive products
Vary in intensity
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The allergy normally remains for the remainder of the
person’s life, causing a reaction upon every point of contact.
Multiple Sensitisations
Multiple allergens within different products
Cross sensitisation means that contact dermatitis caused by a
primary allergen combined with allergies to chemically
similar substances, all of which can cause an outbreak of a
dermatitis reaction at contact
Phototoxic/Photoallergic Reactions
These forms of reaction only occur where there is contact
with an allergic substance and ultra violet light at the same
time.
Allergic Contact Dermatitis
Can occur after only a single contact
Characterised by redness, itching, swelling, papules, and
vesicles
Many factors affect the appearance of dermatitis such as the
location and quantity of allergen
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The allergens cause skin lesions in a sensitised person and
are normally visible 6-48 hours after contact, but can take
four to five days to remedy.
Chronic allergic dermatitis
Prolonged acute dermatitis and is maintained by repeated
contact with the allergic substance
Irritant and allergic dermatitis is often difficult to distinguish
as they can occur at the same time
Diagnosis
Patch tests are used to reproduce as allergic reaction on skin
with specific products
Bacterial culture test - for blistering or crusting lesions
Conducted by a suitably qualified physician or dermatologist
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Burns
Flame
In direct contact with a fire, the cause of which could be from
a multitude of sources.
The length of exposure and intensity of the heat liberated
from the fire will determine the extent of the burn suffered.
Chemical
Herrington (1995) states that “Chemical burns are uncommon,
accounting for only 3% of all burn injuries; however they are
responsible for over 30% of burn deaths”
(Herrington, 1995, p. 264).
Alkalis are more destructive to human tissue than acids due
to the different reactions with the skin and underlying tissue
When chemical exposure is suffered the continuation of
exposure will directly affect the extent of the burn wound.
Acid or alkali burns should be treated initially by continuous
flushing with copious amounts of running water.
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Neutralisation is not recommended, as the heat produced with
neutralisation will exacerbate the injury.
Herrington (1995)
Electrical
Herrington (1995) states “Electrical burns are caused by the
conversion of the electrical energy to thermal energy. As the
current courses through the body, heat is liberated in proportion to
the resistance of the various tissues” (Herrington, 1995, p. 264).
Damage caused by electric current is generally not visible
The majority of the burn damage is to internal tissue, except
to the entry and exit point of the current and burns due to
associated flame proliferation when an electric arc flashes or
heat ignites.
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Herrington (1995)
Types of burn
First-degree (superficial) burns
Most commonly caused by the exposure to ultraviolet
radiation or scalding due to hot liquids or surface contact
Injuries generally do not require hospitalisation and are
treatable without specialist medical attention
This type of burn should heal within a week or so.
Second-degree (partial thickness) burns
Predominately caused by scalding, contact with hot
surfaces or flame
Treated as soon as possible by flushing or where possible
submerging in cold water as this helps to limit the extent
of the burn injury.
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Hospitalisation is necessary for this type of injury to
ensure appropriate treatment is received, recovery within
three to four weeks.
Herrington (1995)
Third-degree (full thickness) burns
Caused by flame, electrical contact, or immersion in hot
liquids
Affected area has constricted blood flow
Specialist treatment is required
Treatment involves the removal of the affected area and
the positioning of grafts
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Herrington (1995)
Mechanical Injury
Callosity
- Hardened skin that forms when the skin is subjected to
constant friction
- Occurs during manual work and can be painful, causing
difficulty at work
Raynaud’s Phenomenon
- The fingertips change colour when exposed to the cold
- Discoloration is the result of a vasopastic reaction to cold
and in severe cases this can lead to necrosis
- Common with workers using vibrating tools such as
jackhammers, pneumatic drills and pounding machines.
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Goh (1990)
Physical Injury
Heat
- The swelling of the lining of the sweat ducts can obstruct
the entrance of the sweat duct leading to sweat retention
causing miliaria
- Symptoms can be as mild as scaling of the skin, or severe
such as itchy popular rashes
- Treatment involves changing the environment of the
worker to reduce sweating and hygiene
Cold
- Frostbite and Raynaud’s phenomenon
- Environments such as cold rooms and in liquefied gas
workers can cause vasoconstriction leading to decreased
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blood supply to the fingertips with severe damage being
tissue damage and necrosis.
Goh (1990)
Radiation effects
- Electromagnetic radiation is dependent on energy level
and dose
- Little or no warning properties such as odour or sound.
Ionising radiation
- Has a high energy level and occurs in waveform such as
X-rays
- Health impact varies with the type of radiation and
intensity
- Occurs in industry such as curing plastics, sterilising,
medical radiography and therapy, and electronic
equipment such as television sets.
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Adams (1999)
Acute radiodermatitis
- Occupational exposure to ionising radiation is usually
localised
- Acute radiodermatitis affects the skin in stages
- Initially, there is blanching of the skin and oedema that
reaches a peak at 48 hours after exposure and rapidly
subsides. From six to ten days the skin begins to change in
colour and texture with considerable pain
- Acute radiodermatitis effects the functioning of the
sebaceous glands and hair follicles. After months of
healing a scar remains present
- As the intensity of exposure to radiation increases, the
effects become worse, with amputation a possibility.
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Adams (1999)
Ultraviolet light radiation
- Common cause of cancer such as melanoma, and
squamous cell carcinoma.
- Enhances the skin ageing process and this can lead to skin
cancer
- Industry use artificial sources of UV radiation, examples
include welding and cutting torches, numerous laboratory
equipment and electric arc furnaces
- Outdoor workers are affected
- Personal protection equipment
- Some medication can cause photosensitivity reaction
effecting toenails and fingernails following exposure to
UV radiation
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Adams (1999)
Irritants and Allergens
Resins
Acrylic - associated with causing allergic contact
dermatitis in the uncured form
- skin irritant and sensitiser
Epoxy - inert form is not a skin sensitiser
- can cause dermatitis
- used in thermoplastics, prosthetics, and
dentures
Polyurethane - skin irritants
- dermatitis caused by direct contact
- used in prosthetics, adhesives and
furniture
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Formaldehyde - skin irritant and sensitiser
- allergic contact dermatitis possible
as formaldehyde is released from the
resin
- used in electrical and manufacturing
industries
Goh (1990)
Rubber Chemicals
Most common skin sensitiser
Allergic contact urticaria
Latex gloves can cause dermatitis
Substitutes include plastic gloves
Solvents
Skin irritants
Can cause cumulative dermatitis in hands
Used for dissolving substances, degreasing and in inks
Used as cleanser
Soaps and Detergents
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Skin irritants
Skin sensitiser in fragrances
Can cause contact dermatitis
Cleansers
Goh (1990)
Foodstuffs
Uncooked food can cause skin reactions
Occupational dermatitis can be cumulative
Allergic contact dermatitis possible with preservatives and
spices
Contact urticaria result of contact with shellfish, fish meat
and fruit
Patch test can confirm allergy
Chefs and food handlers
Plants and Woods
Irritant and allergic contact dermatitis
Plant dermatitis - lesions on the skin
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Wood dermatitis – airborne, exposed skin
Forest workers, florists, gardeners, and horticulturists
Goh (1990)
Metals
Skin sensitiser and irritant
Can cause contact dermatitis
Nickel - skin sensitiser and can cause contact dermatitis
- jewellery, hairdressing and electronics industries
- patch test available to detect nickel
Chromium - not a skin sensitiser
- chromate can cause allergic contact dermatitis
- dermatitis continues after stopping contact
- used in tanning leather and in cement
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Goh (1990)
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Health Risk Assessment
Hazard Identification
- First step in risk assessment
- What is a hazard and what the effects of exposure on
health
- Injury type or disease and exposure conditions.
Dose Response Assessment
- Relationship of dose and the occurrence of an adverse
effect
- Animal studies and human studies, showing route of
exposure, dose type, and the response.
Exposure Assessment
- Amount of exposure from the environment such as
ingestion, absorption, and inhalation.
- Duration and estimated dose of exposure is determined to
be able to identify current and to anticipate future adverse
conditions.
Risk Characterisation
- Determine the extent of the risk with respect to regulations
and legislation.
Adams (1999)
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References
Adams, R.M. (Ed.). (1999). Occupational Skin Disease (3rd ed.).
Philadelphia: W.B. Saunders Company
Berger, T.G., Elias, P.R., and Wintroub, B.U. (1990). Manual of Therapy
For Skin Diseases. New York, U.S.: Churchill Livingstone
Dr. Kevin Macdonald. Occupational Physician, B.Med.Sc., M.B.B.S.,
F.A.F.O.M.
Goh, C.L. (1990). Handbook of Occupational Skin Diseases. Singapore:
P.G. Publishing
Herrington, T and Morse, L. (1995). Occupational Injuries, Evaluation,
Management and Prevention. St Louis Missouri, U. S. A.: Mosby, Year
Book Incorporated
Mc Cunney, R. (1994). A Practical Approach to Occupational and
Environmental Medicine (2nd ed.). Boston: Little, Brown and Company
Snell, R.S. (1986). Clinical Anatomy for Medical Students (3rd ed.). Boston:
Little, Brown and Company
Zenz, C., Dickerson, O., and Horvath, E. (Eds.). (1995). Occupational
Medicine (3rd ed.). St Louis Missouri, U. S. A.: Mosby, Year Book
Incorporated
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