Exposure to flour dust makes bakery workers vulnerable to respiratory diseases, a South African study shows.
A high prevalence of allergic sensitization
and asthma was recently reported in South African supermarket
bakeries. So researchers set out to conduct a detailed exposure
assessment of these bakeries so as to provide the baseline for
a broader intervention study.
A total of 211 full-shift personal samples were collected
on randomly selected individuals within five different job categories
in 18 bakeries. The samples were analyzed for particulate mass
and specific flour dust allergens (wheat, rye, and fungal alpha-amylase).
Exposure models were developed using job, bakery size, tasks,
and specific ingredients used.
The researchers found bread bakers had the highest average (geometric mean)
exposures. For alpha-amylase allergens, most samples were below the limit
of detection for several occupational titles.
Elevated exposure to inhalable
dust particulate as well as wheat and rye allergen concentrations
were seen in large bakeries, bread baking, and in the use of cereal flours,
while tasks such as confectionery work were negatively correlated
with these exposure metrics.
Weighing tasks and use of premix
products were associated with increased exposure to fungal alpha-amylase.
A high correlation between particulate dust and wheat as well as rye was observed, with a much lower correlation
between particulate dust and fungal alpha-amylase.
Overall, a low proportion (39%) of bakery stores implemented
various control measures to reduce dust exposures in the bakeries.
Writing in the Annals of Occupational Hygiene, Mohamed Jeebhay of Centre for Occupational and Environmental Health Research, University of Cape Town and others said, " This study confirms that current exposure control
strategies in supermarket bakery stores are inadequate in reducing
dust exposures to protect the health of bakery workers. "