Abstract:
This is descriptive case control study, from July 2010 to July 2013,
aimed to detect the respiratory epithelium changes in regards to
occupational exposure to cement dust pollution. Sputum samples
were collected from 531 individuals; of who 433 were exposed to
cement dust pollution (cases) and 98 were non exposed (controls),
their ages ranging from 11 to 70 years and genders participated
376/431 male and 155/531 female in the cases. Cytological one
smear was prepared from each sample and demonstrated by
Papanicolaou stain for detection of cytological changes and
AgNOR method for evaluation of the mean count of AgNOR dots
per nucleus. A significant correlation between exposure to cement
dust pollution and respiratory epithelium changes was found
among cases compared to controls. Cytological atypia (dysplasia)
was detected in 21(4.8%) of the cases and was not detected in
controls (P=0.013). Notably, squamous metaplasia was detected
in 236(54.5%) of the cases compared to 43(43.9%) of controls
(P=0.037). Acute inflammatory cells infiltrates were observed in
252(58.2%) of the cases compared to 43(43.9%) of controls
(P=0.007). Chronic inflammatory cells infiltrates were observed in
45(10.4%)
of the
cases compared to
4(4.1%)
of controls
(P=0.032). Asbestos bodies were detected in 59(13.6%) of the
cases and non of the controls (P=0.000). The fungal infection by
Actinomyces israelii and Monilia were detected in 54(13%) and
9(2%) of the cases compared to 1(1%) of controls (p=0.001). Also
were
found
a
significant
relationship
between
respiratory
epithelium changes and duration, closeness, female than male,
surrounding population than workers, and with Alhagz residence.
The mean AgNORs dots counts were elevated in cases (3±.043)
compared to (1.8±.07) in controls (P=0.000), in addition elevated
with long term of duration, 3km to 5km of distance, male,
workers, and with Alhagz village residence. Also it were elevated
in cytological atypia (3.89±0.9) (P=0.000), squamous metaplasia
(3.09±0.8) (P=0.035) and asbestosis (3.32±0.9) (P=0.004). This
study concluded that exposure to cement dust is a risk factor for
occurrence of respiratory epithelium atypical changes, Squamous
metaplasia, susceptibility of infections, inflammatory changes and
asbestosis. The cytological changes increase with duration,
closeness, female than male, surrounding populations than
workers and with Alhagz than other residence. Cytology is a useful
technique in evaluation of environmental and pollution induced
changes in respiratory tract. The mean AgNORs count is a useful
indicator for cellular proliferation activity in respiratory epithelium
and for prediction of the risk of exposure to certain carcinogenic
elements that may induce lung cancer.
