Page iv
Health Hazard Evaluation Report 2009-0131-3171
Mention of any company or product does not constitute endorsement by NIOSH. In
addition, citations to websites external to NIOSH do not constitute NIOSH endorsement
of the sponsoring organizations or their programs or products. Furthermore, NIOSH is not
responsible for the content of these websites. All web addresses referenced in this document
were accessible as of the publication date of this report.
Abbreviations
ACGIH®
American Conference of Governmental Industrial Hygienists
CFR
Code of Federal Regulations
HHE
Health hazard evaluation
IgE
Immunoglobulin E
IOM
Institute of Medicine
kU/L
Killiunits per liter of serum
mg/m
3
milligrams per cubic meter
NAICS
North American Industry Classification System
ND
Not detected
NIOSH
National Institute for Occupational Safety and Health
OEL
Occupational exposure limit
OSHA
Occupational Safety and Health Administration
PEL
Permissible exposure limit
REL
Recommended exposure limit
STEL
Short-term exposure limit
TLV®
Threshold limit value
TWA
Time-weighted average
WEEL™
Workplace environmental exposure level
Page 1
Health Hazard Evaluation Report 2009-0131-3171
Introduction
On April 3, 2009, the National Institute for Occupational Safety and Health (NIOSH) received
a request for a health hazard evaluation (HHE) at a poultry breading plant in Georgia. The
United Food and Commercial Workers union submitted the request. The request stated that
employees at the plant were experiencing asthma, bronchitis, and nasal symptoms from
exposure to breading dust, which consists of flour, spices, and other ingredients.
NIOSH investigators visited the plant on June 24–25, 2009. We held an opening meeting with
plant managers, the corporate health and safety manager, and union representatives to discuss
the HHE request. We observed work processes, practices, and workplace conditions and spoke
with employees. We reviewed material safety data sheets for breading ingredients, the plant’s
respiratory protection program, the Occupational Safety and Health Administration (OSHA)
Log of Work-Related Injuries and Illnesses Form 300 from 2005 to 2009, and environmental
sampling results from 2003 to 2009. We also held confidential interviews with 47 employees
to discuss health and workplace concerns. We sent an interim letter with the findings from this
visit to the participants of the opening meeting. We returned to the plant on March 8–10, 2010,
to further evaluate employees’ exposures to breading dust.
Background
Process Description
More than 400 employees worked in production at this plant, which had two production
shifts and one sanitation shift. The plant received raw chicken from deboning plants.
The chicken was then breaded, flash fried, and frozen; breaded, fully cooked, and frozen;
or marinated and frozen. The plant had six production lines that used interchangeable
components including conveyor belts, marinating tanks, and breading and batter applicators.
One line was devoted to marinating and freezing chicken.
Dry batter and breading mix supplied in paper bags of varying sizes were manually emptied
into dispensing hoppers along the lines. Local exhaust ventilation on the lines could be
connected to the interchangeable components as they were rearranged to accommodate the
type of chicken product being produced.
Baker’s Asthma
Baker’s asthma is a well-known form of occupational asthma. Rhinitis (inflammation
inside the nose) among bakers is common and usually precedes asthma. Conjunctivitis
(inflammation of the white part of the eye and the lining of the eyelids) and skin symptoms
may also occur. Atopy (the predisposition to allergy) is a risk factor for asthma, but sex,
age, and smoking habits do not have a significant influence on sensitization or asthma [De
Zotti et al. 1994; Baur et al. 1998; Houba et al. 1998a]. Symptoms of baker’s asthma may
develop months or years after first exposure, and risk increases with increasing exposure
concentration. In addition to allergy, nonspecific mucous membrane and respiratory irritation
Page 2
Health Hazard Evaluation Report 2009-0131-3171
also occur frequently among those exposed to flour, possibly more commonly than allergic
symptoms [Houba et al. 1998b].
Wheat and other cereal flours are the main causes of baker’s asthma. Wheat flour is a
complex mixture that contains at least 40 antigens [Sander et al. 2001]. Epidemiologic
studies have demonstrated prevalences of sensitization of 5%–28% to wheat among
bakers [Houba et al. 1996]. Variability in these prevalences is due to differing methods for
measuring sensitization. The prevalence of sensitization to flour dust and spices, allergy, and
asthma among poultry breading workers is unknown, as is the range of exposures in this type
of manufacturing environment.
Methods
Previous environmental monitoring for total dust by the plant found employee exposures
that exceeded the OSHA permissible exposure limit (PEL) for particulates not otherwise
regulated. Using this information and observation of plant processes, for our statistical
analysis we classified employees as “lower-exposure” or “higher-exposure.” The lower-
exposure group included employees who worked on lines breading chicken but worked
with product that was already cooked, employees on a line that did not bread chicken, and
other jobs with minimal direct contact with breading dust (Table 1). The higher-exposure
group included production employees who handled flour and other ingredients and uncooked
breaded product (Table 1). Persons who reported prior job assignments at the plant that were
in the higher-exposure group were assigned to the past higher-exposure group.
All production employees at the plant were asked to participate in our evaluation. The
evaluation was designed to compare sensitization and symptoms prevalences between groups
of employees with differing levels of exposure to breading dust and to characterize exposure
to flour dust, wheat, and soy. Full-shift personal breathing zone air samples for inhalable flour
dust, wheat, and soy were collected across job titles on all six lines. Although we did not
evaluate ventilation controls, we observed use of the ventilation systems.
Employees were informed of the benefits and risks of the evaluation and gave signed consent
for participation. We drew participants’ blood and tested it for immunoglobulin E (IgE)
antibody specific to flour dust, wheat, garlic, onion, soybean, corn, and paprika. We also
tested for common aeroallergens (using the AlaTOP®) to assess atopy. A positive antibody
test indicates sensitization to a specific substance.
We administered a questionnaire to all participants, asking about job title, years worked, and
work department; cough; symptoms of asthma; and symptoms of rhinoconjunctivitis (nose
and eye symptoms). Study participants were individually informed in writing of the results of
their blood tests and what they meant.
The methods used for this evaluation are discussed in detail in Appendix A.