Assessment of air pollution effects in the subjects of Khartoum industrial area , Sudan via cytological interpretations

The study was conducted to assess the air pollution-related lung cellular proliferative activity and inflammatory cells infiltrate among Sudanese subjects, who worked at least 8 hours per day. A total of seventy-five workers who worked for at least 5 years in the polluted area were included, sputum/ blood samples were collected to evaluate the cytological atypia and metaplasia. Out of 75 subjects, Cytological atypia and metaplasia were detected among 8% and 16% of the participant respectively, and such types of changes due to the exposure of occupational air pollution were found to be * ADDRESS FOR CORRESPONDENCE: Osman EM, Department of Medical Laboratories Science, Al-Ghad International Colleges for Health Sciences, KSA. E-mail address: myamya88@hotmail.com Osman, E., M., Rahmani, A., H., Babiker, A., Y., Abbass, M., Abuderman, A., Alsammani, M., A. & Ahmad, H., G. (2016). Assessment of air pollution effects in the subjects of Khartoum industrial area, Sudan via cytological interpretations, Global Journal on Advances in Pure & Applied Sciences. [Online]. 07, pp 13-20. Available from: www.propaas.eu 14 statistically significant (P= 0.01 ). Similarly, acute and chronic inflammatory cells infiltrate were identified among 10.7% and 14.7% of the study subject respectively; the changes was statistically significant compared to control (P= 0.001). Exposure to occupational air pollutant was associated with alteration in cells of lungs such atypia, acute and chronic inflammatory cells. This finding supports the earlier studies that long exposure to air pollutants is associated to lung atypical alterations.


Introduction
Lung cancer is one of the commonest cancers worldwide mainly due to tobacco exposure [1].The estimated new lung and bronchus cancer cases in United State, 2014 were 224,210 accounting for about 13% of all cancer diagnoses [2].In the Arab World, the uppermost mortality rates due to lung cancer were estimated in the Northern African Arab (Egypt (20.7%),Morocco (20.4%),Algeria (15.4%) and then Tunisia (9.9%) of the total death).83.3% of a total deaths related to lung cancer in the Arab populations were in males [3].Since Sudan has no national population-based cancer registry, the only sources of lung cancer data are the hospital-based case series and researches.The relative frequency of lung cancer in the reported case series of adult Sudanese was 0.5% [4,10].Lung was not one of the 10 top common cancer site in a study conducted in Khartoum, Sudan between 2009 -2010, the estimated number of incident lung cancer cases was 159 using the Age-standardized rate (ASR) and Khartoum 2009 [11].
Various factors play an important role in the development and progression of lung cancer including cigarette smoking, chewing, and genetic alterations [12,14].Air pollution is one of the main players in development of lung cancer via alteration in the genes/DNA damage.Previous studies have reported an increase lung cancer among workers exposed to constituents of urban air pollution including polycyclic aromatic hydrocarbons and diesel exhaust [15,16].Unfortunately, the exact mechanism of air pollutants in cancer development is not understood completely.It was considered that constituents of air pollution bind to DNA and causes DNA adduct and finally cancer development occurs.Air pollutant or particulate matter also causes inflammation/asthma and reduced lung function.Earlier studies have shown that outdoor air pollution is associated with decreased lung function [17,18].Pollution and smoking can also cause cell death by necrosis, and with the process of apoptosis, which can increase inflammatory strength [19].The current study aimed to assess the relationship between air pollution exposure and lung inflammatory processes and alteration in lung cell in the exposed subjects.

Materials and Methods
A total of seventy five participants from Khartoum industrial area, Sudan who worked for at least the latest 8 hours a day for 5 years or more were investigated for lung cellular and inflammatory changes.The workers who worked for one year or less considered as control.Sputum and blood sample were collected and processed for cytological examination.5 ml of venous blood was taken in EDTA container for differential blood count by using Sysmix haematology analyser (K21).A questionnaire was used to collect demographical data.Each participant was asked to sign ethical consent and ethical consent form was designed and accepted by the ethical committee of Faculty Research Board, FMLS, and Sudan Academy of sciences (SAS).
Sample Processing for cytological examination: Sputum with deep cough was collected in the early morning and the smear was made.The Smears were further treated according to Papanicolaou method *20+.For nuclear and cytoplasmic staining, smears were treated with Harris's Haematoxylin and Papanicolaou Orange G6 solution respectively.Another smear were stained using silver nitrate method for Ag NOR protein sites and mounted with DPX medium and analysis were made.
Cytological assessment of the epithelial atypia: Nuclear enlargement, changed nuclear/cytoplasmic ratio, nuclear hyperchromatism, irregularity of nuclear membranes was calculated.
Statistical analysis: Statistical Package for Social Sciences (version 16) was used for the analysis and to perform Chi-square test for statistical significance (P value).

Discussion
The effect of air pollution on the expose subject was analyzed by cytological methods and total white blood cells count (TWBCs) was measured in various air pollutant exposed subjects.In our study an association between air pollution, lung atypia and metaplasia was noticed.Previous finding has shown that stronger associations between traffic-related air pollution and lung metaplasia and the relative risk increases with cigarette smoking [21].The exact cause of dysplasia, lung atypia and metaplasia is not known exactly but it is considered that various factor responsible for the alteration in lung cells including air pollutants.Air pollutants also cause respiratory disordered such as asthma and other respiratory related complications.Earlier epidemiological studies have shown an association between exposure to motor vehicle traffic emission and allergic symptoms and reduced lung function [22].
Our study also observed Inflammatory infiltrate in a considerable number in exposed subjects.The possible reason of inflammatory infiltrate in lung is due to the body defence system, which plays an important role in the production of inflammatory response against foreign particle such as dust, pollutant and particulates.Several studies have confirmed the pollutants shows an important role in increases of neutrophils or eosinophils.Earlier study has revealed that traffic policemen showed a statistically significant increase in the percentage neutrophil cell count as compared to the Healthy Subjects [23].Another study results showed that patients living within 1000 m of highways showed an increased risk of bronchitis and increased risk of an asthma diagnosis [24].
In our finding results confirm that considerable number of subjects has symptoms such acute and chronic inflammation and chest diseases.On the other side, significant number of subjects also showed low total WBC count.The exact explanation in this issue is not achieved but it is hypothesized that subject exposed with air pollutant for long time especially who worked at least 8 hours per day for several years shows weak immunity and also shows other complications such chest diseases and chest tightness.Previous finding showed that a variety of inhaled materials stimulate alveolar macrophages to produce proinflammatory cytokines including IL-1, IL-6, and IL-8 and TNF-α *25, 28].

Conclusion
Our results indicated an association of long term exposure of air pollutant and lung cell alterations such atypia and metaplasia and air pollution might lead to causes acute and chronic inflammation.Additionally, long term exposure also causes changes in WBC count and finally altered the immune response.

Figure 5 .
Figure 5. Description of the TWBCs count by cytological findings

Table 2 .
Distribution of cases by levels of TWBCS