|
Upon completion of this course, you will be able to:
-
Define and discuss what is meant by latex
- Identify
the various items containing latex that may be found in
the healthcare setting
- List
and discuss the types of allergic reactions to latex that
can be seen in the workplace
- Identify
and discuss the steps that can be taken to minimize those
allergic reactions
This course is intended to alert healthcare personnel to the
potential for allergic reactions in some individuals using
natural rubber latex (NRL) products, particularly gloves,
in the workplace setting. Natural rubber is utilized in a
variety of products including gloves, airways, airway masks,
medication vial tops, anesthesia bags, various catheters,
supplies for intravenous use, dental dams, balloons, and other
products. NRL glove use in the health care setting has risen
dramatically since about 1987, due to the increased threat
of contracting HIV, hepatitis B, and other infectious agents
in the course of delivering health care to patients and the
need for barrier protection. Thus, the frequency of exposure
to NRL among health care and other workers has increased.
NRL
products are also used to provide barrier protection from
some chemicals and other agents in health care and other environments.
(NOTE: While NRL gloves are useful for certain purposes, they
are not universally suitable. The properties of a glove material
for a specific use must be determined in advance of use. Gloves
appropriate for protection from the particular chemical or
agent must be used.) NRL gloves are also used to prevent contamination
of products in some workplaces (e.g., electronics and drug
manufacturing). Natural rubber articles are manufactured in
some workplaces (e.g., manufacturers of medical gloves, industrial
gloves, balloons, rubber bands, boots and shoes, and many
other products).
With
more widespread use of NRL gloves, there has been an increase
in reported NRL allergies, among patients as well as among
workers, notably health care workers. Rarely, these allergies
can be fatal. In addition to reports from the dermatology,
allergy, and pulmonary literature of severe skin and respiratory
symptoms, life-threatening reactions to NRL products have
been noted in pediatric patients with spina bifida who had
undergone numerous surgical procedures, resulting in repeated
NRL exposure. In addition, the US Food and Drug Administration
(FDA) received reports of numerous severe allergic reactions,
including several deaths, associated with exposure to NRL
enema cuffs in providing care to sensitized patients.
NRL
is manufactured from a variety of plants, but mainly the rubber
tree, Hevea brasiliensis. The milky fluid from the
tree contains variable amounts of proteins which may be absorbed
through the skin or inhaled and cause allergic reaction in
susceptible workers. NRL contains many proteins. A number
of these proteins, such as hevamine, hevein, and rubber elongation
factor (REF), may initiate allergic reaction to NRL. Studies
have indicated that corn starch powder, added to gloves to
facilitate donning and removal, can serve as a carrier for
the allergenic proteins from the NRL.
In
addition, gloves, including those made from NRL as well as
some other materials, may contain chemical accelerators such
as thiuram, carbamates, and benzothiazoles to which a worker
may also develop sensitization, resulting in allergic contact
dermatitis. Antioxidants, biocides, soaps, and other chemicals
used in the processing of NRL products may contribute to sensitization
as well.
In
1987 the Centers for Disease Control and Prevention (CDC)
recommended universal precautions, the concept that blood
and certain body fluids from all individuals should be approached
as if potentially infectious. The use of barrier protection
was subsequently required by OSHA's bloodborne pathogens standard.
The increased use of latex gloves in a variety of settings
greatly increased the exposure of health care workers to NRL.
The
two major routes of exposure include dermal exposure and inhalational
exposure. NRL protein absorption has been reported to be enhanced
when perspiration collects under latex clothing articles.
Exposure may also occur by the respiratory route, particularly
when glove powder acts as a carrier for NRL protein which
becomes airborne when the gloves are donned or removed. Some
investigations have indicated that powder free gloves with
reduced protein content reduce risk of development of NRL
allergy. Some questions regarding powder free glove shelf
life and ease of use have arisen and are being addressed.
Importantly, only non-NRL gloves must be used by those workers
who are allergic to NRL.
The
majority of health care workers are able to use NRL products
to care for most patients. Variations exist in the reported
prevalence of NRL allergy. This variation is probably due
to different levels of exposure and methods of estimating
latex sensitization or allergy. Nevertheless, prevalence studies
indicate that from around 6% to 17% of the exposed health
care workforce is allergic to NRL. In a survey of active duty
dental officers in the U.S. Army, the prevalence of allergic
symptoms correlated with NRL use was reported to be 13.7%.
An investigation of dental workers using NRL skin prick testing
at two consecutive American Dental Association meetings revealed
allergic responses in 9.1-9.7% of dental hygienists and assistants,
although dentists showed a lower rate of 5.1-6.7%. The general
population exhibits a lower rate of NRL sensitization (approximately
1 to 6%). These prevalence statistics are based on seroprevalence
as well as skin test positivity and/or allergic manifestations
and do not refer to the more serious anaphylactic response,
which is rare but potentially life threatening in some individuals.
In
addition to dentists, health care workers reported to have
especially high risks include operating room personnel consistently
exposed to NRL (i.e., operating room nurses, physicians, and
technicians). NRL allergy has also been reported in greenhouse
workers, hairdressers, doll manufacturing workers, and workers
in a glove manufacturing plant, and may pose a risk to others
as well.
Use
of natural rubber products may result in several varieties
of reactions (see table). These reactions include irritant
and several types of allergic reactions. They can vary from
localized redness and rash to nasal, sinus, and eye symptoms
to asthmatic manifestations including cough, wheeze, shortness
of breath, and chest tightness; and rarely, systemic reactions
with swelling of the face, lips, and airways that may progress
rapidly to shock and, potentially, death.
When
gloves are associated with skin lesions, the most common reaction
is irritant contact dermatitis. Irritant contact dermatitis
may be due to direct irritation from gloves or glove powder,
but may also be due to other causes, such as irritation from
soaps or detergents, other chemicals, or incomplete hand drying.
Irritant contact dermatitis presents as dried, cracked, split
skin. Although irritant contact dermatitis is not in itself
an allergic reaction, the breaking of the intact skin barrier
due to these lesions may afford a pathway for latex proteins
to gain access, and thus promote development of allergy.
The
second type of reaction that may be associated with glove
use is allergic contact dermatitis (also known as type IV
delayed hypersensitivity or allergic contact sensitivity).
When glove use has been associated with this reaction, it
appears to be due to the chemicals used in processing NRL
or other glove materials. The allergic contact dermatitis
has an appearance similar to the typical poison ivy reaction,
with blistering, itching, crusting, oozing lesions. Also,
like poison ivy, this dermatitis may appear a day or two after
the use of gloves or exposure to other sources of chemical
sensitizers.
The
third and potentially most serious type of reaction sometimes
associated with glove use is a true IgE/histamine-mediated
allergy (also called immediate or type I hypersensitivity)
to glove protein [in the case of NRL allergy, to NRL protein(s)].
This type of reaction can involve local or systemic symptoms.
Localized symptoms include contact urticaria (hives) which
appear in the area where contact occurred (in the case of
gloves, the hands), but which can spread beyond that area
and become generalized. More generalized reactions include
allergic rhinoconjunctivitis and asthma. The presence of allergic
manifestations to NRL indicates an increased risk for anaphylaxis,
a rare but serious reaction experienced by some individuals
who have developed an allergy to certain proteins (e.g., insect
stings, natural rubber, penicillin).
This
type I reaction can occur within seconds to minutes of exposure
to the allergen (in the case of NRL, to natural rubber proteins)
either by touching a product with the allergen (e.g., gloves)
or by inhaling the allergen (e.g., powder to which natural
rubber proteins from gloves have adsorbed). When such a reaction
occurs, it can progress rapidly from swelling of the lips
and airways to shortness of breath, and may progress to shock
and death, sometimes within minutes. While any of these signs
and symptoms may be the first indication of allergy, in many
workers with continued exposure to the allergen (in the case
of NRL allergy, to natural rubber proteins), there is progression
from skin (contact urticaria) to respiratory symptoms over
a period of months to years. Some studies indicate that individuals
with latex allergy are more likely than latex non-allergic
persons to be atopic (have an increased immune response to
some common allergens, with symptoms such as asthma or eczema.
Once NRL allergy occurs, allergic individuals continue to
experience symptoms, which have included life-threatening
reactions, not only on exposure to NRL in the workplace but
also upon receiving or accompanying a family member receiving
health care services at inpatient as well as office-based
settings. In addition, such reactions have occurred on exposure
to consumer goods such as balloons, condoms, and other products.
Moreover, some affected individuals continue to experience
asthmatic symptoms even without contact with NRL. Therefore,
development of allergy to NRL in an individual has lifestyle
implications beyond the workplace.
Types
of Reactions
|
Type
Reaction
|
Symptoms/Signs
|
Cause
|
Prevention
/ Management
|
|
| Irritant
Contact Dermatitis |
scaling,
drying, cracking of skin |
direct
skin irritation by gloves, powder, soaps/detergents,
incomplete hand drying |
Obtain
medical diagnosis, avoid irritant product, consider
use of cotton glove liners , consider alternative
gloves/products |
Allergic
Contact Dermatitis
(Type IV delayed hypersensitivity or allergic contact
sensitivity) |
blistering,
itching, crusting (similar to
poison ivy reaction) |
accelerators
(e.g., thiurams, carbamates, benzothiazoles) processing
chemicals (e.g., biocides, antioxidants)
Consider penetration of glove barrier by chemicals |
Obtain
medical diagnosis, identify chemical. Consider use
of glove liners such as cotton Use alternative glove
material without chemical Assure glove material
is suitable for intended use (proper barrier) |
NRL
Allergy - IgE/histamine mediated
(Type I immediate hypersensitivity) --------------------------
A) Localized contact urticaria which may be associated
with or progress to:
B) Generalized Reaction |
---------------------
Hives in area of contact
with NRL
---------------------
Include: generalized urticaria, rhinitis, wheezing,
swelling of mouth, shortness of breath. Can progress
to anaphylactic shock |
NRL
proteins: direct contact with or breathing NRL proteins,
including glove powder containing proteins, from
powdered gloves or the environment |
Obtain
medical diagnosis, allergy consultation, substitute
non-NRL gloves for affected worker and other non-NRL
products Eliminate exposure to glove powder - use
of reduced protein, powder free gloves for coworkers
Clean NRL-containing powder from environment Consider
NRL safe environment |
|
|
Recommended
Strategies - Risk Reduction
|
It is of primary importance that barrier protection be used
when hands would otherwise contact infectious materials or
hazardous chemicals. OSHA's bloodborne pathogens standard
requires that gloves be worn when it is reasonably anticipated
that hand contact may occur with blood, other potentially
infectious materials, mucous membranes, non-intact skin, or
contaminated items or surfaces, as well as when performing
most vascular access procedures [29 CFR 1910.1030, paragraph
(d)(3)(ix)]. NRL is a glove material that has been used in
the health care environment for barrier protection for a number
of years. In response to reported NRL allergy in some patients
and health care workers, measures have been recommended to
reduce the risk of NRL allergy in workers.
Primary
prevention involves reducing potential development of allergy
by reducing unnecessary exposure to NRL proteins for all workers.
Food service workers or gardeners, for example, do not need
to use NRL gloves for food handling or gardening purposes.
Gloves made of NRL as well as synthetic materials have been
cleared for marketing as medical gloves by the FDA and can
be used effectively for barrier protection against bloodborne
pathogens. General administrative procedures that an institution
can follow to reduce worker exposure to NRL proteins include:
- If
selecting NRL gloves for worker use, designating NRL as
a choice only in those situations requiring protection from
infectious agents;
-
When selecting NRL gloves, choosing those that have lower
protein content. Selecting powder free gloves offers the
additional benefit of reducing systemic allergic responses;
and
-
Providing alternative suitable non-NRL gloves as choices
for worker use (and as required by OSHA's bloodborne pathogens
standard [29 CFR 1910.1030, paragraph (d)(3)(iii)] for workers
who are allergic to NRL gloves).
Providing
alternative suitable non-NRL gloves as choices for worker
use (and as required by OSHA's bloodborne pathogens standard
[29 CFR 1910.1030, paragraph (d)(3)(iii)] for workers who
are allergic to NRL gloves).
Use
of powder free gloves has been shown to reduce the dissemination
of NRL proteins into the environment and decrease the likelihood
of reactions by both the inhalation and dermal routes. Appropriate
work practices when wearing hand protective equipment, including
NRL gloves, include avoidance of contact with other body areas
such as the eyes or face. Handwashing after glove removal
is required by OSHA's Bloodborne Pathogens Standard [paragraph
(d)(2)(v)] and helps to minimize powder and/or NRL remaining
in contact with the skin. Thorough clean-up of any residual
powder in the workplace with appropriate vacuum filters will
decrease employees' exposure as well.
Since
the reason for wearing gloves is to provide barrier protection
from hazardous substances, substitute materials must maintain
an adequate barrier protection and be appropriate for the
hazard. At a minimum, gloves made from NRL or other materials
and used for a medical purpose should be labeled as medical
gloves. Such gloves must meet the FDA criteria for marketing,
manufacturing, and testing of medical gloves. The Health Industry
Manufacturers Association (HIMA), in conjunction with the
FDA, has proposed general guidelines for use of medical gloves
with some recommendations for those individuals who are allergic
to natural rubber.
One institution has reported that a coordinated effort to
identify NRL sensitive individuals and reduce the use of "high
allergenic" natural rubber latex gloves substantially
reduced aeroallergen levels and costs.4 Other investigators
have reported that some NRL allergic workers have been able
to work wearing nonlatex gloves when their coworkers wore
powder free latex gloves.
Effective
September 30, 1998, the FDA requires labeling statements for
medical devices which contain natural rubber and prohibits
the use of the word "hypoallergenic" to describe
such products.8 NRL gloves with a reduced level of chemical
accelerators must be labeled to eliminate confusion associated
with the "hypoallergenic" claim and to provide more
specific information to the user. Some NRL gloves and other
devices produced before the effective date of the FDA regulation
may not carry the NRL labeling or may be labeled "hypoallergenic".
Such products may still be in use in some facilities. It should
be noted that such products should not be presumed to be NRL
free. The hypoallergenic claim referred to the chemical additives,
and such gloves may be powder free; however, they contain
the NRL proteins to which NRL allergic workers react.3The
FDA is currently exploring options for reducing exposure to
NRL proteins and powder. It is important to note that these
FDA regulations do not apply to non-medical devices, including
utility gloves.
|
Recommended
Worker Evaluation and Management
|
The
administrative procedures outlined above may not be sufficient
to protect all individuals who have already developed NRL
allergy. The American College of Allergy, Asthma, and Immunology
has suggested that "safe zones" (areas in which
non-NRL products are used and NRL proteins have been thoroughly
removed from the environment) may be needed to protect those
workers who are already sensitized to NRL. Health care facilities
should develop policies and procedures for reducing the risk
of NRL allergies in the workplace. Prudent risk reduction
strategy involves an initial survey and assessment, with a
coordinated effort to identify and catalogue all NRL products
used in the workplace. An ongoing program, involving close
coordination with resource and materials management staff,
should be established to monitor the NRL content of incoming
products so that management staff can be prepared to choose
appropriate products for offering non-NRL alternatives to
control NRL exposure as well as for creating NRL safe zones.
Mechanisms for reporting and managing cases should be in place.
It
is not possible, at present, to determine which workers will
become allergic to NRL proteins, the extent of an individual
worker's reaction, or the length of time required for such
allergic reactions to develop. It is also not possible, at
present, to predict who will progress from local contact urticaria
to the more dangerous allergic reactions, nor when this may
occur.
Laboratory
and clinical evidence indicates that an association exists
between allergy to natural rubber proteins and allergy to
certain foods and plants (e.g., avocado, banana, kiwi, chestnut)
and some aeroallergens (e.g., pollens, grasses). A history
of multiple surgeries has also been reported to be a risk
factor for NRL allergy. In some institutions, periodic screening
questionnaires for symptoms of NRL allergy in workers with
current or past history of significant NRL exposure (e.g.,
surgical personnel) have been useful for ascertaining reaction
rates and managing those individuals experiencing reactions.
A medical evaluation of hand dermatitis, by a physician experienced
in dermatologic diagnoses, is essential for taking preventive
steps and assuring effective therapeutic measures. Evaluation
of signs/symptoms associated with latex allergy should be
accomplished under the direction of a physician with expertise
in NRL allergy, with additional medical testing and treatment
made available if indicated.
Provision
of latex-free procedure trays and crash carts for treatment
of natural rubber allergic individuals has been recommended.
Although the fundamentals of emergency response
(i.e.,
assuring airway, breathing, and circulation) remain of primary
importance should a worker develop symptoms (including those
caused by NRL allergy) requiring resuscitation, these situations
should be anticipated in the workplace and provision of immediate
access to non-natural rubber containing equipment considered.
Investigation
continues into various aspects of NRL allergy; our understanding
of some issues continues to evolve. Meanwhile, workers and
workplaces need to be aware of the present state of knowledge
regarding NRL allergy and methods of protection. Workers should
be advised of symptoms of NRL allergy as well as primary and
secondary preventive measures for decreasing the risk of NRL
allergy development and NRL allergic reactions in workers
who are allergic.
The
National Institute for Occupational Safety and Health (NIOSH)
has published an Alert titled Preventing Allergic Reactions
to Natural Rubber Latex in the Workplace which is presented
below:
The
National Institute for Occupational Safety and Health (NIOSH)
requests assistance in preventing allergic reactions to natural
rubber latex* among workers who use gloves and other products
containing latex. Latex gloves have proved effective in preventing
transmission of many infectious diseases to health care workers.
But for some workers, exposures to latex may result in skin
rashes; hives; flushing; itching; nasal, eye, or sinus symptoms;
asthma; and (rarely) shock. Reports of such allergic reactions
to latex have increased in recent years --especially among
health care workers.
At
present, scientific data are incomplete regarding the natural
history of latex allergy. Also, improvements are needed in
methods used to measure proteins causing latex allergy. This
Alert presents the existing data and describes six case reports
of workers who developed latex allergy. The document also
presents NIOSH recommendations for minimizing latex-related
health problems in workers while protecting them from infectious
materials. These recommendations include reducing exposures,
using appropriate work practices, training and educating workers,
monitoring symptoms, and substituting nonlatex products when
appropriate.
*In
this document, the term "latex" refers to natural
rubber latex and includes products made from dry natural rubber.
Natural rubber latex is the product manufactured from a milky
fluid derived mainly from the rubber tree, Hevea brasiliensis.
Composition
of Latex
Latex
products are manufactured from a milky fluid derived from
the rubber tree, Hevea brasiliensis. Several chemicals
are added to this fluid during the processing and manufacture
of commercial latex. Some proteins in latex can cause a range
of mild to severe allergic reactions. Currently available
methods of measurement do not provide easy or consistent identification
of allergy-causing proteins (antigens) and their concentrations.
Until well accepted standardized tests are available, total
protein serves as a useful indicator of the exposure of concern.
The chemicals added during processing may also cause skin
rashes. Several types of synthetic rubber are also referred
to as "latex," but these do not release the proteins
that cause allergic reactions.
Products
Containing Latex
A
wide variety of products contain latex: medical supplies,
personal protective equipment, and numerous household objects.
Most people who encounter latex products only through their
general use in society have no health problems from the use
of these products. Workers who repeatedly use latex products
are the focus of this Alert. The following are examples of
products that may contain latex:
Emergency
Equipment
Blood pressure cuffs
Stethoscopes
Disposable gloves
Oral and nasal airways
Endotracheal tubes
Tourniquets
Intravenous tubing
Syringes
Electrode pads
Personal
Protective Equipment
Gloves
Surgical masks
Goggles
Respirators
Rubber aprons
Office
Supplies
Rubber bands
Erasers
Hospital
Supplies
Anesthesia masks
Catheters
Wound drains
Injection ports
Rubber tops of multidose vials
Dental dams
Household
Objects
Automobile tires
Motorcycle and bicycle handgrips
Carpeting
Swimming goggles
Racquet handles
Shoe soles
Expandable fabric (waistbands)
Dishwashing gloves
Hot water bottles
Condoms
Diaphragms
Balloons
Pacifiers
Baby bottle nipples
Individuals
who already have latex allergy should be aware of latex-containing
products that may trigger an allergic reaction. Some of the
listed products are available in latex-free forms.
Latex
in the Workplace
Workers
in the health care industry (physicians, nurses, dentists,
technicians, etc.) are at risk for developing latex allergy
because they use latex gloves frequently. Also at risk are
workers with less frequent glove use (hairdressers, housekeepers,
food service workers, etc.) and workers in industries that
manufacture latex products.
|
TYPES
OF REACTIONS TO LATEX
|
Three
types of reactions can occur in persons using latex products:
- Irritant
contact dermatitis
- Allergic
contact dermatitis (delayed hypersensitivity)
- Latex
allergy
Irritant
Contact Dermatitis
The most common reaction to latex products is irritant
contact dermatitis -- the development of dry, itchy, irritated
areas on the skin, usually the hands. This reaction is caused
by skin irritation from using gloves and possibly by exposure
to other workplace products and chemicals. The reaction can
also result from repeated hand washing and drying, incomplete
hand drying, use of cleaners and sanitizers, and exposure
to powders added to the gloves. Irritant contact dermatitis
is not a true allergy.
Chemical
Sensitivity Dermatitis
Allergic contact dermatitis (delayed hypersensitivity,
also sometimes called chemical sensitivity dermatitis) results
from exposure to chemicals added to latex during harvesting,
processing, or manufacturing. These chemicals can cause skin
reactions similar to those caused by poison ivy. As with poison
ivy, the rash usually begins 24 to 48 hours after contact
and may progress to oozing skin blisters or spread away from
the area of skin touched by the latex.
Latex
Allergy
Latex allergy (immediate hypersensitivity) can be a
more serious reaction to latex than irritant contact dermatitis
or allergic contact dermatitis. Certain proteins in latex
may cause sensitization (positive blood or skin test, with
or without symptoms). Although the amount of exposure needed
to cause sensitization or symptoms is not known, exposures
at even very low levels can trigger allergic reactions in
some sensitized individuals.
Reactions
usually begin within minutes of exposure to latex, but they
can occur hours later and can produce various symptoms. Mild
reactions to latex involve skin redness, hives, or itching.
More severe reactions may involve respiratory symptoms such
as runny nose, sneezing, itchy eyes, scratchy throat, and
asthma (difficult breathing, coughing spells, and wheezing).
Rarely, shock may occur; but a life-threatening reaction is
seldom the first sign of latex allergy. Such reactions are
similar to those seen in some allergic persons after a bee
sting.
|
LEVELS
AND ROUTES OF EXPOSURE
|
Studies
of other allergy-causing substances provide evidence that
the higher the overall exposure in a population, the greater
the likelihood that more individuals will become sensitized.
The amount of latex exposure needed to produce sensitization
or an allergic reaction is unknown; however, reductions in
exposure to latex proteins have been reported to be associated
with decreased sensitization and symptoms.
Figure
1. Dust produced by removing a latex glove containing powder.
The
proteins responsible for latex allergies have been shown to
fasten to powder that is used on some latex gloves. When powdered
gloves are worn, more latex protein reaches the skin. Also,
when gloves are changed, latex protein/powder particles get
into the air, where they can be inhaled and contact body membranes
(see Figure 1). In contrast, work areas where only powder-free
gloves are used show low levels or undetectable amounts of
the allergy-causing proteins.
Wearing
latex gloves during episodes of hand dermatitis may increase
skin exposure and the risk of developing latex allergy. The
risk of progression from skin rash to more serious reactions
is unknown. However, a skin rash may be the first sign that
a worker has become allergic to latex and that more serious
reactions could occur with continuing exposure.
Workers
with ongoing latex exposure are at risk for developing latex
allergy. Such workers include health care workers (physicians,
nurses, aides, dentists, dental hygienists, operating room
employees, laboratory technicians, and hospital housekeeping
personnel) who frequently use latex gloves and other latex-containing
medical supplies. Workers who use latex gloves less frequently
(law enforcement personnel, ambulance attendants, funeral-home
workers, fire fighters, painters, gardeners, food service
workers, and housekeeping personnel) may also develop latex
allergy. Workers in factories where latex products are manufactured
or used can also be affected.
Atopic
individuals (persons with a tendency to have multiple allergic
conditions) are at increased risk for developing latex allergy.
Latex allergy is also associated with allergies to certain
foods especially avocado, potato, banana, tomato, chestnuts,
kiwi fruit, and papaya. People with spina bifida are also
at increased risk for latex allergy.
|
DIAGONISING
LATEX ALLERGY
|
Latex
allergy should be suspected in anyone who develops certain
symptoms after latex exposure, including nasal, eye, or sinus
irritation; hives; shortness of breath; coughing; wheezing;
or unexplained shock. Any exposed worker who experiences these
symptoms should be evaluated by a physician, since further
exposure could result in a serious allergic reaction. A diagnosis
is made by using the results of a medical history, physical
examination, and tests.
Taking
a complete medical history is the first step in diagnosing
latex allergy. In addition, blood tests approved by the Food
and Drug Administration (FDA) are available to detect latex
antibodies. Other diagnostic tools include a standardized
glove-use test or skin tests that involve scratching or pricking
the skin through a drop of liquid containing latex proteins.
A positive reaction is shown by itching, swelling or redness
at the test site. However, no FDA-approved materials are yet
available to use in skin testing for latex allergy. Skin testing
and glove-use tests should be performed only at medical centers
with staff who are experienced and equipped to handle severe
reactions.
Testing
is also available to diagnose allergic contact dermatitis.
In this FDA-approved test, a special patch containing latex
additives is applied to the skin and checked over several
days. A positive reaction is shown by itching, redness, swelling,
or blistering where the patch covered the skin.
Occasionally, tests may fail to confirm a worker who has a
true allergy to latex, or tests may suggest latex allergy
in a worker with no clinical symptoms. Therefore, test results
must be evaluated by a knowledgeable physician.
Once
a worker becomes allergic to latex, special precautions are
needed to prevent exposures during work as well as during
medical or dental care. Certain medications may reduce the
allergy symptoms, but complete latex avoidance (though quite
difficult) is the most effective approach. Many facilities
maintain latex-safe areas for affected patients and workers.
|
HOW
COMMON IS LATEX ALLERGY?
|
The
prevalence of latex allergy has been studied by several methods:
- Questionnaires
to assess reactions to latex gloves
- Medical
histories of reactions to latex-containing products
- Skin
tests
- Tests
for latex antibodies in a worker's blood
Reports
about the prevalence of latex allergy vary greatly. This variation
is probably due to different levels of exposure and methods
for estimating latex sensitization or allergy. Recent reports
in the scientific literature indicate that from about 1% to
6% of the general population and about 8% to 12% of regularly
exposed health care workers are sensitized to latex. Among
sensitized workers, a variable proportion have symptoms or
signs of latex allergy. For example, one study of exposed
hospital workers found that 54% of those sensitized had latex
asthma, with an overall prevalence of latex asthma of 2.5%.
Prevalence rates up to 11% are reported for non-health care
workers exposed to latex at work.
Several
reasons may exist for the large numbers of latex allergies
recently reported in workers
- Workers
rely increasingly on latex gloves to prevent the transmission
of human immunodeficiency virus (HIV), hepatitis B virus,
and other infectious agents as outlined in Recommendations
for Prevention of HIV Transmission in Health-Care Settings
[CDC 1987] and in Guidelines for Prevention of Transmission
of Human Immunodeficiency Virus and Hepatitis B Virus to
Health-Care and Public-Safety Workers [CDC 1989].
-
Since
1992, the Occupational Safety and Health Administration
(OSHA) has required employers to provide gloves and other
protective measures for their employees [29 CFR*1910.1030,
Bloodborne pathogens].
*Code of Federal Regulations. See CFR in references.
- Some
manufacturers may have produced more allergenic gloves because
of changes in raw materials, processing, or manufacturing
procedures to meet the increased demand for latex gloves.
These production changes may account partly for the varied
concentrations of extractable latex proteins reported for
latex gloves (up to a 3,000-fold difference in gloves from
various manufacturers). Variations may also exist between
lots produced by the same manufacturer.
- Physicians
are more familiar with latex allergy and have improved methods
for diagnosing it.
The
following case reports briefly describe the experiences of
six workers who developed latex allergy after occupational
exposures. These cases are not representative of all reactions
to latex but are examples of the most serious types of reactions.
They illustrate what has occurred in some individuals.
Case
No. 1
A
laboratory technician developed asthma symptoms after wearing
latex gloves while performing blood tests. Initially, the
symptoms occurred only on contact with the gloves; but later,
symptoms occurred when the technician was exposed only to
latex particles in the air.
Case
No. 2
A
33-year-old woman sought medical treatment for occupational
asthma after 6 months of periodic cough, shortness of breath,
chest tightness, and occasional wheezing. She had worked for
7 years as an inspector at a medical supply company, where
her job included inflating latex gloves coated with cornstarch.
Her symptoms began within 10 minutes of starting work and
worsened later in the day (90 minutes after leaving work).
Symptoms disappeared completely while she was on a 12-day
vacation, but they returned on her first day back at work.
Case
No. 3
A
nurse developed hives in 1987, nasal congestion in 1989, and
asthma in 1992. Eventually she developed severe respiratory
symptoms in the health care environment even when she had
no direct contact with latex. The nurse was forced to leave
her occupation because of these health effects.
Case
No. 4
A
midwife initially suffered hives, nasal congestion, and conjunctivitis.
Within a year, she developed asthma, and 2 years later she
went into shock after a routine gynecological examination
during which latex gloves were used. The midwife also suffered
respiratory distress in latex-containing environments when
she had no direct contact with latex products. She was unable
to continue working.
Case
No. 5
A
physician with a history of seasonal allergies, runny nose,
and eczema on his hands suffered severe runny nose, shortness
of breath, and collapse minutes after putting on a pair of
latex gloves. He was successfully resuscitated by a cardiac
arrest team.
Case
No. 6
An
intensive care nurse with a history of runny nose, itchy eyes,
asthma, eczema, and contact dermatitis experienced four severe
allergic reactions to latex. The first reaction began with
asthma severe enough to require treatment in an emergency
room. The second and third reactions were similar to the first.
The fourth and most severe reaction occurred when she put
on latex gloves at work. She went into severe shock and was
successfully treated in an emergency room.
Conclusions
Latex
allergy in the workplace can result in potentially serious
health problems for workers, who are often unaware of the
risk of latex exposure. Such health problems can be minimized
or prevented by following the recommendations outlined in
this Alert.
The
following recommendations for preventing latex allergy in
the workplace are based on current knowledge and a common-sense
approach to minimizing latex-related health problems. Evolving
manufacturing technology and improvements in measurement methods
may lead to changes in these recommendations in the future.
For now, adoption of the recommendations wherever feasible
will contribute to the reduction of exposure and risk for
the development of latex allergy.
Employers
Latex
allergy can be prevented only if employers adopt policies
to protect workers from undue latex exposures. NIOSH recommends
that employers take the following steps to protect workers
from latex exposure and allergy in the workplace:
- Provide
workers with nonlatex gloves to use when there is little
potential for contact with infectious materials (for example,
in the food service industry).
- Appropriate
barrier protection is necessary when handling infectious
materials [CDC 1987]. If latex gloves are chosen, provide
reduced protein, powder-free gloves to protect workers from
infectious materials.
The goal of this recommendation is to reduce exposure
to allergy-causing proteins (antigens). Until well accepted
standardized tests are available, total protein serves as
a useful indicator of the exposure of concern.
- Ensure
that workers use good housekeeping practices to remove latex-containing
dust from the workplace:
o Identify areas contaminated with latex dust for frequent
cleaning (upholstery, carpets, ventilation ducts, and plenums).
o Make sure that workers change ventilation filters and
vacuum bags frequently in latex-contaminated areas.
- Provide
workers with education programs and training materials about
latex allergy.
- Periodically
screen high-risk workers for latex allergy symptoms. Detecting
symptoms early and removing symptomatic workers from latex
exposure are essential for preventing long-term health effects.
- Evaluate
current prevention strategies whenever a worker is diagnosed
with latex allergy.
Workers
Workers
should take the following steps to protect themselves from
latex exposure and allergy in the workplace:
-
Use nonlatex gloves for activities that are not likely to
involve contact with infectious materials (food preparation,
routine housekeeping, maintenance, etc.).
- Appropriate
barrier protection is necessary when handling infectious
materials [CDC 1987]. If you choose latex gloves, use powder-free
gloves with reduced protein content:
o Such gloves reduce exposures to latex protein and thus
reduce the risk of latex allergy (though symptoms may still
occur in some workers).
o So-called hypoallergenic latex gloves do not reduce the
risk of latex allergy. However, they may reduce reactions
to chemical additives in the latex (allergic contact dermatitis).
- Use
appropriate work practices to reduce the chance of reactions
to latex:
o When wearing latex gloves, do not use oil-based hand creams
or lotions (which can cause glove deterioration) unless
they have been shown to reduce latex-related problems and
maintain glove barrier protection.
o After removing latex gloves, wash hands with a mild soap
and dry thoroughly.
o Use good housekeeping practices to remove latex-containing
dust from the workplace:
§ Frequently clean areas contaminated with latex dust
(upholstery, carpets, ventilation ducts, and plenums).
§ Frequently change ventilation filters and vacuum
bags used in latex-contaminated areas.
- Take
advantage of all latex allergy education and training provided
by your employer:
o Become familiar with procedures for preventing latex allergy.
o Learn to recognize the symptoms of latex allergy: skin
rashes; hives; flushing; itching; nasal, eye, or sinus symptoms;
asthma; and shock.
- If
you develop symptoms of latex allergy, avoid direct contact
with latex gloves and other latex-containing products until
you can see a physician experienced in treating latex allergy.
- If
you have latex allergy, consult your physician regarding
the following precautions:
o Avoid contact with latex gloves and other latex-containing
products.
o Avoid areas where you might inhale the powder from latex
gloves worn by other workers.
o Tell your employer and your health care providers (physicians,
nurses, dentists, etc.) that you have latex allergy.
o Wear a medical alert bracelet.
- Carefully
follow your physician's instructions for dealing with allergic
reactions to latex.
ADDITIONAL
INFORMATION
For additional information about latex allergy, call 1-800-35-NIOSH
(1-800-356-4674); or visit the NIOSH Home Page on the World
Wide Web at http://www.cdc.gov/niosh/homepage.html
You
may access the following latex allergy website directly or
by selecting Latex Allergy through the NIOSH Home Page:
http://www.familyvillage.wisc.edu/lib_latx.htm
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