Biomass smoke exposure as a serious healthhazard for women

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Biomass smoke exposure as a serious health hazard for women

Aylin BABALIK¹, Nadi BAKIRCI², Mahşuk TAYLAN¹, Leyla BOSTAN¹, Şule KIZILTAŞ¹, Yelda BAŞBUĞ¹, Haluk C. ÇALIŞIR¹

1SB Süreyyapaşa Göğüs Hastalıkları ve Göğüs Cerrahisi Eğitim ve Araştırma Hastanesi, Göğüs Hastalıkları Kliniği, İstanbul,

2Acıbadem Üniversitesi Tıp Fakültesi, Halk Sağlığı Anabilim Dalı, İstanbul.

ÖZET

Kadınlarda önemli bir sağlık tehdidi olarak biomass maruziyeti

Giriş:Özellikle kadınlarda, sağlığa zararlı partikülleriyle birlikte biomass, akciğer hastalıklarına neden olmaktadır. Bu ça- lışma, kadınlarda akciğer hastalığına sebep olan biomass maruziyetini araştırmak için planlanmıştır.

Materyal ve Metod:Eylül 2008-Mart 2009 tarihleri arasında Süreyyapaşa Göğüs Hastalıkları ve Göğüs Cerrahisi Eğitim ve Araştırma Hastanesinde yatırılarak tedavi edilen kronik obstrüktif akciğer hastalığı (KOAH), astım, bronşektazi, tüberkü- loz veya interstisyel akciğer hastalığı olan toplam 100 kadın (ortalama yaş 55.13 ± 17.65 yıl) hasta çalışmaya dahil edildi.

Biomass maruziyeti konusunda veri toplanması, hastanede meslek, eğitim seviyesi, doğum yeri, ısıtma ve pişirme sırasın- da biomass dumanına maruz kalma (tezek, odun, kömür, kuru bitkiler) ve maruziyet yılı değerlendirildi.

Bulgular:KOAH (%22), akciğer kanseri (%12), bronşit (%8), tüberküloz (%26) ve interstisyel akciğer hastalığı (%17) olan kadınlar çalışmaya dahil edildi. En sık saptanan meslek ev hanımlığı idi (%86). Sigarayı aktif kullananların, bırakmış olan- ların ve hiç kullanmamış olanların oranları sırasıyla %6, %22 ve %72 idi. Hastaların %67’si köyde, %9’u ilçede doğmuştu.

Bölge dağılımına göre, en sık bölge %29 oranıyla İç Anadolu Bölgesi idi. Biomassa maruziyet en sık, odun (%92), tezek (%30), kömür (%23) ve kuru bitkiler (%23) ile olmaktadır. Ortalama maruziyet yılı odun için 52.6 (17.6) yıl, tezek için 40.8 (17.9) yıl, kuru bitkiler için 48.1 (20.8) yıl ve kömür için 38.5 (21.4) yıldı. En sık biomass maruziyeti, %97 oranıyla köyde,

%79 oranıyla şehirde ve %89 oranıyla tüm ülkede şeklindeydi.

Sonuç:Bizim bulgularımız, kadınlarda biomass maruziyetinin önemini göstermektedir. Aynı zamanda kadınlar ve çocuk- lar için maruziyet seviyesini ölçen detaylı analitik epidemiyolojik çalışmalara gerek olduğunu gösterir.

Anahtar Kelimeler: Biomass maruziyeti, solunumsal hastalık, kadın, Türkiye.

SUMMARY

Biomass smoke exposure as a serious health hazard for women

Aylin BABALIK¹, Nadi BAKIRCI², Mahşuk TAYLAN¹, Leyla BOSTAN¹, Şule KIZILTAŞ¹, Yelda BAŞBUĞ¹, Haluk C. ÇALIŞIR¹

Yazışma Adresi (Address for Correspondence):

Dr. Aylin BABALIK, SB Süreyyapaşa Göğüs Hastalıkları ve Göğüs Cerrahisi Eğitim ve Araştırma Hastanesi, Göğüs Hastalıkları Kliniği, İSTANBUL - TURKEY

e-mail: aylinbabalik@gmail.com

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INTRODUCTION

Indoor air pollution (IAP) is a major environmental and public health hazard for many of the world’s poorest most vulnerable people. There has been an increasing scientific interest in indoor pollution since the second half of 1980 (1). IAP resulting from combustion of biomass fuels has now been recognised as a relevant risk factor for respiratory disorders especially in developing countries in relation to the shift from use of biofuel to petroleum products (kerosene, LPG) and electricity in developed countries (2).

Biomass fuel, or biofuel, refers to any plant or animal based material deliberately burned by humans as their primary source of domestic energy for cooking, home heating and lightening. While the wood is the most common biofuel, use of animal dung and crop residues is also widespread (2). Typically burnt in open fires or poorly functioning stoves, the use of these fuels leads to very high levels of IAP. Smoke exposure affects mainly women and also young children accompanying their mot- hers during cooking and other household activities (2).

Around 50% of the world’s population uses biomass fuels ranging from near zero in industrialized countries to

more than 80% in countries like China, India and sub- Saharan Africa. In Latin America, approximately 50- 75% of households were reported to use biomass fuels for cooking, especially in rural areas (1). In Turkey, use of biomass fuels was documented to be 30% in urbani- zed areas; 30% in rural areas and 90% in Central Ana- tolia, East Anatolia and Southeastern Anatolia regions (3).

Biomass smoke contains thousands of substances, many of which have a significant potential to damage human health. The most damaging substances are car- bon monoxide, nitrous dioxides, sulphur oxides (more with coal), formaldehyde and polycyclic organic mat- ter which includes carcinogens such as benzo(a)pyre- ne (1,2).

There is now consistent evidence that biomass smoke exposure increases respiratory and non-respiratory diseases. A significant relation of smoke exposures to the risk of childhood acute respiratory infections, pneumo- nia in particular and respiratory diseases seen in women including chronic bronchitis and chronic obstructive pulmonary disease, asthma, lung cancer and lung fibrosis was demonstrated. Besides, evidence of an inc-

1Clinic of Chest Diseases, Sureyyapasa Chest Diseases and Chest Surgery Training and Research Hospital, Istanbul, Turkey,

2Department of Public Health, Faculty of Medicine, Acibadem University, Istanbul, Turkey.

Introduction:Lung diseases caused by biomass exposure cause a significant health hazard particularly amongst women.

The present study was designed to investigate biomass exposure in women suffering from lung disease.

Materials and Methods:A total of 100 women [mean (SD) age: 55.13 (17.65) years] hospitalized for chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis, tuberculosis or interstitial lung disease were included in this study conducted between September 2008-March 2009 in three chest disease clinics at Sureyyapasa Chest Diseases and Chest Surgery Training and Research Hospital. Data collection on biomass exposure was based on application of hospital-based survey questionnaire including items on occupation, level of education, place of birth (location, region), exposure to bi- omass fuel fumes for heating and cooking purposes (animal dung, wood, charcoal, dried plant) and years of exposure with animal dung, wood, charcoal, dried plant.

Results:COPD in 22% patients, lung carcinoma in 12%, bronchitis in 8%, tuberculosis in 26%, and interstitial lung disease in 17% were the diagnosis for hospitalization. The most identified occupation was housewifery 86%. Active, former and non- smokers composed 6%, 22% and 72% of the population. Birth place was village in 67% patients while districts in 9%. Accor- ding to regional distribution, the most common place of birth was Central Anatolia region in (29%). Exposure to biomass fuels was identified in all of patients including wood (92%), animal dung (30%), charcoal (23%), and dry plant (23%). Me- an (SD) years of exposure was identified to be 52.6 (17.9) years for wood, 40.8 (17.9) years for animal dung, 48.1 (20.8) years for dry plant and 38.5 (21.4) years for charcoal. The most common type of biomass exposure was wood in village (97%), city (79%) and county (89%).

Conclusion:Findings indicating impact of biomass exposure in women seem to emphasize the need for analytic epidemi- ologic studies assessment measuring biomass exposure levels-particularly for women and young children.

Key Words: Biomass exposure, respiratory disease, women, Turkey.

Tuberk Toraks 2013; 61(2): 115-121 • doi: 10.5578/tt.4173

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reased risk of tuberculosis was also shown by a number of studies (1,2).

The present study was designed to investigate the effects of biomass exposure in hospitalized women suffering from lung disease.

MATERIALS and METHODS

A total of 100 women [mean (SD) age: 55.13 (17.65) years] hospitalized for chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis, tuberculosis or interstitial lung disease were included in this study conducted between September 2008-March 2009 in three chest disease clinics at the Sureyyapasa Chest Diseases and Chest Surgery Training and Research Hospital, Istanbul, Turkey.

Being ≥ 18 years of age and to be hospitalized for a respiratory disease including asthma, bronchiectasis, tuberculosis and interstitial lung disease were the inclusi- on criteria. Patients lacking a definite clinical diagnosis or cooperation to answer questionnaire were excluded from the study.

Data collection on biomass exposure was based on application of hospital-based survey questionnaire to the study sample selected through random sampling.

Questionnaire included items on occupation, level of education, place of birth (location, region), exposure to biomass fuel fumes for heating and cooking purposes (animal dung, wood, charcoal, dried plant) and years of exposure with animal dung, wood, charcoal, dried plant. Besides use of flueless systems such as floor furnace, barbecue, fireplace or bottled gas for heating was considered to be risky exposure and years of exposure was also recorded for the heating methods.

Data on symptoms, respiratory function tests, findings of spirometry, physical examination, high resolution of computerized tomography, chest X-ray, bacteriological investigation (sputum smear and culture results) were collected from medical records.

COPD diagnosis was made via spirometry and clinical assessment and patients who had spirometric measu- rement FEV₁/FVC < 0.70 and characteristic symptoms of COPD such as chronic and progressive dyspnea, co- ugh and sputum production were considered to have COPD according to GOLD guidelines (4).

Patients who had symptoms of recurrent episodes of wheezing, breathlessness, chest tightness and coug- hing at night or early morning and who were under asthma treatment were considered to have asthma in accordance with GINA guidelines (5).

Diagnosis of tuberculosis was based on smear or culture positivity of bacteriological sputum or histopatholo- gical confirmation. Diagnosis of interstitial lung disease and bronchiectasis was performed radiologically via high resolution of computerized tomography.

Statistical Analysis

Descriptive statistics were used. Continuous variables will be summarized using mean and standard deviation (for normally distributed variables) and median and quartiles (for non-normally distributed variables). Ca- tegorical variables will be summarized with percent in each category.

RESULTS

Mean (SD) age of the study population composed of 100 women was 55.13 (17.65) years.

COPD in 22 (22%) patients, lung carcinoma in 12 (12%) patients, bronchitis in 8 (8%) patients, tuberculosis in 26 (26%) patients, and interstitial lung disease in 17 (17%) patients were the diagnosis for hospitalization. Of 100 patients 48 (48%) were illiterate, while 3 (33.3%) were university graduates. The most commonly identified occupation was housewifery (86%). Active, former and non-smokers composed 6%, 22% and 72% of the population, respectively and 66.7% of non-smokers identified evidence of passive smoking due to presence of other smokers at home (Table 1).

Birth place location was village in 67% patients while districts in 9%. According to regional distribution, place of birth was Central Anatolia region in 29 (29%), Eastern Anatolia region in 23 (23%), Black Sea region in 22 (22%), Marmara region in 20 (20%), Mediterrane- an region in 3 (3%) and Aegean region in 2 (2%) (Tab- le 2).

Migration was evident in 12 (12%) patients in the first decade of their lives while 37 (37%) patients identified that they migrated in the second decade and 60 (60%) patients in the third decade of their lives.

The most common type of biomass exposure was wood in village (97%), city (79%) and county (89%) (Tab- le 3).

Exposure to biomass fuels was identified in all of patients including wood (92%), animal dung (30%), charcoal (23%), and dry plant (23%). Mean (SD) years of exposure was identified to be 52.6 (17.9) years for wood, 40.8 (17.9) years for animal dung, 48.1 (20.8) years for dry plant and 38.5 (21.4) years for charcoal (Table 4).

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DISCUSSION

COPD, asthma, lung fibrosis, interstitial lung diseases, pulmonary tuberculosis and lung cancer are considered among the respiratory diseases associated with exposure of IAP. Women and children seem to be at gre- ater risk of adverse health effects resulting from the IAP since they spend more time indoors compared to rest of the population (1).

Accordingly in our study population composed prima- rily of housewives (86%) who were spending majority of their time indoors with household activities, the significant exposure to biomass fumes from the heating and cooking was evident. Indeed, all of the women included this study was identified to have biomass fuels exposure in the past, especially early years of their li- Table 1. Demographic and basic clinical features of

patients (n= 100).

n (%) Age (years) (mean ± SD) 55.13 ± 17.65 Diagnosis

Tuberculosis 26 (26)

COPD 22 (22)

Bronchiestasis 15 (15)

Interstitial lung disease 17 (17)

Asthma 12 (12)

Educational status

Illiterate 48 (48)

Literate 7 (7)

Primary education 30 (30)

Secondary education 6 (6)

High school 6 (6)

University 3 (3)

Occupation

Housewifery 86 (86)

Others 14 (14)

Smoking status

Active smoker 6 (6)

Former smoker 22 (22)

Non-smoker 72 (72)

COPD: Chronic obstructive pulmonary disease.

Table 2. Distribution of place of birth with respect to geographical region and location (n= 100).

n (%) Region

Mediterranean region 3 (3) Eastern Anatolia region 23 (23)

Aegean region 2 (2)

Central Anatolia region 29 (29)

Black Sea region 22 (22)

Marmara region 20 (20)

Location

Village 67 (67)

City 24 (24)

County 9 (9)

Table 3. Distribution of biomass fules types with respect to birth place location (n= 100).

Biomass fuels types n (%)

Village 67 (67)

Wood 65 (97)

Charcoal 16 (24)

Animal dung 26 (39)

Dry plant 20 (30)

City 24 (24)

Wood 19 (79)

Charcoal 6 (25)

Animal dung 1 (4)

Dry plant 2 (8)

County 9 (9)

Wood 8 (89)

Charcoal 1 (11)

Animal dung 3 (33)

Dry plant 1 (11)

Table 4. Type and year of exposure to biomass fuel in the study population (n= 100).

Overall exposure Years of exposure

n (%) Mean (SD)

Wood 92 (92) 52.6 (17.9)

Charcoal 23 (23) 38.5 (21.4)

Animal dung 30 (30) 40.8 (17.9) Dry plant 23 (23) 48.1 (20.8)

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ves with almost more than 40 years of average exposure to animal dung, dry plant and charcoal.

People from lower socioeconomic status have been considered to be more susceptible to tuberculosis which is a significant socioeconomic public health is- sue (6). In this line, indicating higher use of biomass fuels in rural areas of Turkey including people from lower socioeconomic level, Central Anatolia (29%) and Eas- tern Anatolia (23%) were the most commonly identified geographical regions of place of birth and to be born in a village (67%) predominated in our population. Be- sides, in correlation to their low socioeconomic level, half of our patients were identified to be illiterate.

While wood has been considered as the most commonly used biofuel, use of animal dung and crop residues was also documented to be widespread (7). Ac- cordingly wood usage was very common (93%) in our population.

The evaluation of the medical records showed that out of 100 female patients, tuberculosis was evident in 26%, COPD in 22%, bronchiectasis in 15%, interstitial diseases in 17%, and asthma in %12.

IAP has been considered a risk factor for COPD by the Global Strategy for the Diagnosis Management, and Prevention of Chronic Obstructive Lung Disease (4).

Albeit not consistent, the association between IAP exposure and increased risk of chronic bronchitis with possible progression to COPD, emphysema and cor pulmonale was reported in majority of studies. Accor- dingly, the association between exposure to biomass smoke and chronic bronchitis or COPD was documented in some cross-sectional, case control and cohort studies. Exposure was usually estimated via question- naires based on hours by the wood stove, or hours mul- tiplied by years of exposure. The evidence for chronic bronchitis has generally been defined by questionnaire symptoms. Spirometrical evaluation was done. Additi- onally, women exposed to biomass fumes were reported to be more likely to suffer from chronic bronchitis and COPD compared with urban women even though the prevalence of smoking was higher among the latter group (8-15).

In Turkey and Iran, women exposed to biomass for cooking/heating showed significantly higher prevalence of chronic bronchitis and COPD while recent studies showed contribution of wood smoke and poverty to reduced lung function as an important risk factor for develop- ment of COPD among non-smoking women (16-18).

First large epidemiological study conducted in Turkey showed that biomass exposure, as a sole reason for

COPD, was significantly common among female patients living in rural areas (54.5%) (19). In a systematic review and meta-analysis of 25 studies concerning respiratory diseases associated with solid biomass fuel exposure in rural women and children, the overall pooled ORs indicated significant associations with chronic bronchitis in women (OR 2.52, 95% CI 1.88 to 3.38) and COPD in women (OR 2.40, 95% CI 1.47 to 3.93) (20).

There are still relatively few published studies from developing countries about the relation between asthma and IAP while exposure is not measured and confounding is not dealt with in some of these studies. Altho- ugh evidence from developing countries suggests that IAP may increase risk of developing asthma for children, a number of studies reported no effect for children (8,21-25).

Evidence in adults comes from in rural China which reported adjusted OR for wheezing and asthma for the group with occupational exposure to wood smoke to be 1.36 (1.14-1.61) and 1.27 (1.02-1.58), respectively (20,24). In a systematic review and meta-analysis of 25 studies concerning respiratory diseases associated with solid biomass fuel exposure in rural women and children, no significant association with asthma in children or women was noted (20).

A few studies have found an increased risk of tuberculosis from exposure biomass fuels, although none of them measured the level of exposure specifically and confounding not fully accounted for in one (26-28). In these studies, adjusted OR for socio-economic factors OR were 2.58 (1.98-3.37), 2.4 (1.04-5.6) (26-28). As- sociation between use of biofuel and tuberculosis was found similar with adjustment only for age (27). An increase in risk of tuberculosis may result from reduced resistance to infection, as exposure to smoke interferes with mucociliary defenses and decreases antibacterial properties of lung macrophages (29). Biomass smoke exposure may be an additional factor in the well-estab- lished relationship between poverty and tuberculosis and may be explained by factors including malnutriti- on, overcrowding and limited access to health care.

There is some evidence also that wood smoke exposure may be associated with interstitial lung disease (inf- lammation of the lung structure leading to fibrosis) in developed countries (30-32). In a small case control study, patients with cryptogenic fibrosing alveolitis were determined to be more likely to live in a house he- ated by a wood fire (33). Several studies have descri- bed lung fibrosis which resembles pneumoconiosis including cases with progressive massive fibrosis among

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subjects exposed to wood smoke. Exposure to inorga- nic or organic dusts may coexist in these patients. Non- occupational silicosis has also been reported in developing countries, and attributed to sand storms, but these subjects have often also exposed to biomass smoke (34-36).

The existing studies on the relationship between biomass usage and respiratory diseases in developing countries, provide important evidence of associations with a range of serious and common health problems but suffer from a number of methodological limitations, namely:

a. The lack of detailed and systematic pollution exposure determination,

b. The fact that all studies to date have been observa- tional and,

c. That many have dealt inadequately with confounding (1).

In conclusion, poverty is one of the main barriers to the adoption of cleaner fuels and slow pace of develop- ment in many countries implies that biofuels will conti- nue to be used by the poor for many decades. The available data indicate the significant impact of biomass fuels usage on the respiratory health worldwide and that protective public health measures should be imp- lemented (1). Our findings indicating significant impact of biomass exposure in women seem to emphasize the need for the detailed analytic epidemiologic studies concerning assessment biomass exposure to be able develop practical, robust and valid methods for measuring the exposure levels and patterns-particularly for women and young children.

CONFLICT of INTEREST None declared.

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