Respiratory Diseases and Allergies in Two Polluted Areas in East ...

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Respiratory Diseases and Allergies in Two Polluted Areas in East Germany Joachim Heinrich,1 Bernd Hoelscher,1 Matthias Wjst1 Beate Ritz,2 Josef Cyrys,1 and H.-Erich Wichmann"13 1GSF Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Epidemiologie, Neuherberg, Germany; 2UCLA School of Public Health, Centers of Occupational and Environmental Health, Los Angeles, CA, 90095-1772, USA; 3Lehrstuhl fuer Epidemiologie, Institut fuer medizinische lnformationsverarbeitung, Biometrie und Epidemiologie, der Ludwig-Maximilians Universitaet Muenchen, Oberschleissheim, Germany -

This cross-sectional epidemiological study collected health data for 2,470 school children between 5 and 14 yeas of age (89% of elgible children) who had lived most of their lives in either one of two counties trongly impacted by industrial pollution (Bitterfeld and Hettstedt) or in a neighborng county without any sources of industrial pollution (Zerbst). The objective of the study was to eimine whether regional diffierences-with respect to the occurrence of childhood respiratory diseases and symptoms or allergies-exist and, if such dierences are found, whether dty persist when we adjust for the effecs of known risk factors such as medical and sociodemographic factors or fiators related to the indoor environment. Controlling for medical, sociodemographic, and indoor factors, according to parental reports, children residing in Hettstedt have about a 50% increased lifetime prevalence for physician-diagnosed allergies, eczema, and bronchitis compared to children fiom Zerbst and about twice the number of respiratory symptoms such as wheeze, shortness of breath, and cough without cold. Sensitization to common aeroaliergen according to skin prick tests [odds ratio (OR) _ 1.38; 95% confidence interval (CI), 1.02-1.86] and specific IgE levels (OR = 1.75; CI, 1.31-2.33) was more common for children from Hetsedt than cildren from the nonpolluted county. Bitterfeld children, on the other hand, more often received a diagnosis of asthma and eczema than children residing in Zerbst and also showed dightly increased sensitization rates. In condusion, industrial pollution related to mining and smelting operations in the county of Hettstedt were associated with a higher lifetime prevalence of respiratory disorders and an increased rate of allergic sensitizion in children between the ages of 5 and 14 years. Further studies are needed to determine what role the high dust content of heavy metals plays in Hettstedt. Key words: allergy, bronchial reactivity, children, eastern Germany, IgE, industrial pollution, respiratory health, skin prick test. Environ Healb P"ept 107:53-62 (1999). [Online 9 December 1998]

bIt hap:llehpneal. niehs. nib.gpovldocs/199/1 07p53-62heinrich/absr m.

In industrialized countries of the Northern Hemisphere, the prevalence of atopic diseases such as asthma, atopic dermatitis, and allergic rhinitis appear to have increased during the last decades (1-4). Possible explanations for this increase are changes of diagnostic criteria, lifestyle factors, and environmental factors such as indoor and outdoor air pollution. Ambient air pollution has previously been associated with adverse chronic health effects such as diseases of the airways, including chronic bronchitis and dry cough (5-11) and a decrease of lung function (12-13). However, it is not clear what role ambient air pollution or other environmental factors might play in the development of atopic diseases, or if they are even involved in this process. Epidemiologic studies examining the long-term effects of ambient air pollution on the occurrence of asthma and allergies have not been unequivocal. In most crosssectional studies, asthma prevalence was not related to higher levels of sulfur dioxide or

total suspended particulates (5,8,14-15). Some of these studies did not adequately control for potential confounding factors such as indoor air pollution or individual

risk factors. One U.S. study found an association of asthma with increases in trafficdependent pollutants (16). Two studies conducted in West Germany showed increased prevalences of hay fever (17) and allergic sensitization (18) depending on proximity of residence to streets with heavy traffic, while another study found no such association (154. Recent publications reported higher rates of atopy among children (3,20-22) and young adults (23,24) living in western compared to eastern Germany. In the late 1980s and the early 1990s, air pollution levels in eastern Germany exceeded western levels by an order of magnitude, especially with regard to sulfur dioxide and total suspended particles. This observation further adds to the controversy about the impact of environmental factors on atopic diseases. It is not clear,-however, whether the east-west comparison adequately controlled for many potential risk factors that might be differentially distributed between these two distinct German populations. The goal of the present study was to determine whether regional differences exist for the occurrence of respiratory and

Environmental Health Perspectives * Volume 107, Number 1, January 1999

atopic diseases and symptoms in school-age children who exclusively live in eastern Germany. Furthermore, we examined whether known or suspected medical and sociodemographic risk factors or factors related to the indoor environment could explain regional differences. In general, region provided a proxy measure for longterm environmental pollution, specifically air pollution, because the populations of the three counties included in this study have been exposed to air pollution to different degrees. Prior to 1992, air-monitoring measurements were not documented in a manner comprehensive enough to allow sophisticated air-pollution effect analyses such as time-series analyses. However, the available data were useful for general characterization of the air quality experienced by residents of each county.

Methods Study area. The study was conducted in the state of Sachsen-Anhalt [formerly German Democratic Republic (GDR)]. The data presented in this paper were collected between September 1992 and July 1993. The results are based on the first of three subsequent surveys embedded in a cohort study investigating the effects of environmental factors on respiratory health. The Bitterfeld study area includes the towns of Bitterfeld and Wolfen and four adjoining villages located in a mountainless region of Sachsen-Anhalt. The population of the county of Bitterfeld consisted of Address correspondence to J. Heinrich, GSF Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Epidemiologie, Ingolstaedter Landstrasse l,D-85758 Neuherberg, Germany. We thank H. Schneller and K Honig-Blum for handling data; H. Adam and H. Bach for examining the children; I. Hbrhold, I. Keller, S. Loewe, and D. Bodesheim for collecting the blood and urine specimens; T. Schafer and J. Ring for advice conceming the dermatological examinations; G. Burmester, J. Rudzinski, B. Hollstein, H. Machander, D. Albrecht, and C. Boettcher for gathering regional data and local assistance; all teachers in Hettstedt, Zerbst, and Bitterfeld and the local school authorities and health care centers for their support; and all parents and chil-

dren for their participation.

This study was supported exclusively by a governmental funding source, the Federal Environmental Agency (Umweltbundesamt), grant Z 1.5-917420/15. Received 22 April 1998; accepted 14 August 1998.

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Table 1. Annual means of S02, particulates, and heavy metals in dust fall at the three ambient monitoring stations in Zerbst (control), Bitterfeld (polluted), and Hettstedt (polluted), 1984-1994 --------Zerbst Bitterfeld Hettstedt Pollutant Emission SO2 (tons/km2/year) 30.1a 272.7a NA 1984 15.4a 4.7a 155.1a 1990 NA NA NA 1993 Dust (tons/km2/year) 112.4 NA 8.8 1984 78 51.6a 2.7a 1990 NA NA NA 1993

NO,1985(tons/km2/year) 1990 1993 Lead (tons/km2/year) 1984 1989 Arsenic (kg/km2/year) 1984 1989 Ambient concentration SO (passive sampling) (pg/m3)

1988 1990 1992 SO2 (active measurement) (pg/m3) 1988 1991 1994

NO2 (active measurement) (pg/m3) 1988 1991 1993 1994 Dust fall (g/m2/day) 1988 1990 1994 TSP (pg/rm3) 1993

1.98 NA

1a

15.2a

NA

NA

NA NA

NA NA

0.34b

NA NA

NA NA

l15.2b

NA NA NA

229a 1818a

123a 8181

73c

61C

NA

NA 84e

NA 50d,e 29f

0Q22b

13.9b

130 44f

38'

NA NA 21 cg 22f

NA NA 23C

0.21 a,d

0.96-1.40a 0.83-1.07a

0.37-0.40a 0.3140.38a

0.08f 44C

48c,g

0.12-0.14f 65C

NA NA 21C

22f

NA

9gf.

0.13-0.16'

PM10 (pg/Mr3)

NA 40 33 October 1993-March 1994 Black smoke (pg/m3) NA 42h 26h October 1993-March 1994 Heavy metals in dust fall Lead (pg/m2/day) NA NA NA 1985 147.6-367.1 e 18.0de 1992 18.0-41.2e 47.0-280.2f 16.2f 19.4-26.1 f 1994 Cadmium (pg/m2/day) NA NA NA 1985 1.2de 1.6-2.6e 1992 35_4.7e 1994 0.3f 0.4-0.5f 0.8-3.5f Chromium (pg/m2/day) NA NA NA 1985 7.7-21.9e 5.1d,e 5.8e 1992 1994 1.9f 2.9-4.4 1.1-2.3f Nickel (pg/m2/day) NA NA NA 1985 8.0d,e 14.4-25.8e 37-5.7e 1992 1994 1.6f 2.5-3.8f 3.8-18.0 Arsenic (pg/m2/day) NA NA NA 1985 NA NA NA 1992 2.4f 1.6-2.6f 2.3-6.8f 1994 Abbreviations: TSP, total suspended particulate matter; PM,,, particulate matter 9% from baseline after the cold air challenge test Mfheal diameter >3 mm. "Grasses, birch, hazel, mugwort, plantain.

'>0.35 kl/I.

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Articles * Adverse health effects and air pollutants

small subgroup of children (n = 585) for which we were able to obtain complete data]. We examined potential effect modification for each of the selected covariates including interaction terms with region in our models. We did not find any effect modification and, thus, excluded these terms from our final regression models. We report adjusted odds ratios (ORs) and 95% confidence intervals (CIs). All computations were performed using SAS Version 6.09 (SAS Institute, Cary, NC) in a Unix environment.

Results Descriptive analyses. Table 3 displays crude

prevalences of parent-reported diagnoses and symptoms, bronchial reactivity in our cold air-challenge test, signs of atopic disease noted by the study dermatologist, and the sensitization rate for major aeroallergens by study region. Parents of children living in Hettstedt county reported the highest proportion of lifetime diagnoses of atopic diseases and asthmoid respiratory symptoms. Asthma diagnosed by a physician ("ever asthma bronchiale" or "wheezy bronchitis") was reportedly more frequent for Bitterfeld (4.4%) and Hettstedt (2.1%) youths than for children living in the comparison region of Zerbst (1.6%). The parental reports of higher proportions of asthmoid symptoms experienced by children residing in Hettstedt and Bitterfeld were substantiated by the results from the cold air challenge test performed during this survey. The same trend as for asthma diagnosis was found for increased bronchial reactivity: children from Bitterfeld most often responded positively (19.4%), followed by children from Hettstedt (16.7%) and Zerbst (13.9%). Yet, we did not find regional differences for other lung function tests (FEVI, etc; results not shown). We also observed slightly higher allergic sensitization rates among children from Hettstedt and Bitterfeld, according to both methods employed (the skin prick test and IgE measurements). Most of the sensitized children showed a skin reaction to pollen allergens. Sensitization to food allergens, eggs, and milk were negligible (0.3% of all tested children). Specific IgE increases were found for the common antigens pollen and mites. Cat-specific IgE and IgE against fungi were less frequent. Finally, children from Zerbst (1.8%) suffered less from atopic dermatitis than children from Bitterfeld (2.7%) or Hettstedt (3.2%), according to the assessment of our study dermatologist. A small trend was found for parental reports of previously diagnosed eczema (8.2-11.7%). A greater proportion of parents reported childhood

Table 4. Prevalence rates of potential predictors of health outcomes in 5-14-year-old children of two polluted areas (Bitterfeld and Hettstedt) in comparison with the control area (Zerbst) Zerbst Bitterfeld Hettstedt Predictors Prevalence Frequencya Prevalence Frequencya Prevalence Frequencya Medical history Low birth weight (20 m2 Child shared bedroom 44.8 52.9 (360/804) 49.2 (384/726) (377/767) Dampness or visible molds 20.2 19.0 (163/808) 17.6 (139/730) (136/774) District or central heating 50.3 55.0 (410/815) 46.7 (404/734) (364/779) 35.8 Heating with coke/ 37.8 (285/797) 36.8 (274/724) (281/763) coal/briquettes Heating with gas 8.7 4.0 (69/797) 8.1 (29/724) (62/763 Child's room Child's room near main 22.7 22.0 (183/807) 22.3 (157/715) (172/772)

street/industry

Wall-to-wall carpet in child's room Environmental tobacco smoke Current or prior exposure at home Mother smoked during pregnancy Contact with pet Contact to cats Other Child ever attended

67.0

(547/816)

57.4

(421/734)

67.9

(529/779)

53.2 6.4

(431/810) (51/797)

61.5 6.2

(448/728) (45/731)

59.0 3.5

(457/774) (27/767)

39.0

(313/803)

23.3

(169/726)

34.8

87.1

(705/809)

91.4

(672/735)

89.0

(268/771) (685/770)

day-care center 'The variation in total subjects is a result of missing data.

bAtopic diseases (asthma, hay fever, eczema, other allergy) in at least or

tonsillitis in Hettstedt than in Zerbst (70.0% vs. 63.6%); this was paralleled by a higher proportion of abnormal or removed tonsils diagnosed in our physical examinations (data not shown). Potential predictors of health outcomes. Table 4 presents the distribution of factors potentially related to the health outcomes of interest by region. Most of these possible risk factors were quite homogenously distributed throughout the three counties. Slightly more parents from Bitterfeld and Hettstedt reported suffering from atopic diseases (28.4% and 26.5%, respectively) than parents living in Zerbst (24.9%). Bitterfeld children more often lived in houses built before 1960 and in houses made out of concrete. Because these structures were usually multilevel complexes, dwelling on the ground floor was less common in Bitterfeld (31.8%) compared to Zerbst (46.1%) and Hettstedt (45.9%). Bitterfeld children were also more likely to share their bedrooms than their peers living in Zerbst or Hettstedt. Consequently, Bitterfeld residents also reported less living space per person. Of all homes, 18.9% were described as damp or showed visible mold. Approximately half of the homes were heated by a long-distance steam pipeline or a central heating sys-

Environmental Health Perspectives * Volume 107, Number 1, January 1999

tem. Homes in Bitterfeld used gas furnaces less often for heat. Parents reported wall-towall carpeting in the child's room and the use of mattresses made of horsehair, curtains, chipboards, and upholstered furniture in similar proportions. Currently, as well as throughout their lives, a higher proportion of Bitterfeld and Hettstedt children had lived with a household member who smoked tobacco, and mothers of children from Bitterfeld and Zerbst more often reported smoking during pregnancy. Children from Zerbst had more contact to pets. Multivariate analyses. Logistic regression modeling allowed us to adjust for the influence of potential confounders while examining the effect of the study region on each of the health outcome measures of interest separately. Tables 5-7 show crude and adjusted (i.e., adjusted for all of the above mentioned variables) ORs for residing in Bitterfeld or Hettstedt versus Zerbst

(reference county).

We found 1.5-2 times more parents in Hettstedt who reported that physicians had diagnosed their children with asthma (adjusted OR = 1.97), allergies (adjusted OR = 1.69), eczema (adjusted OR = 1.52), or bronchitis (adjusted OR = 1.52). On the 57

Articles * Heinrich et al.

Table 5. Adjusted odds ratios (ORs) and 95% confidence intervals (Cis) for lifetime prevalence of self-reported physician's diagnoses Allergy Bronchitis Asthma or wheezy bronchitis (n= 1,768) (n= 1,773) (n= 1,773) Cl Cl Adj OR Adj OR Cl Adj OR Potential predictors 1.44* (0.99-2.09) 0.97 (0.76-1.24) (0.55-2.43) 1.16 Age 8-10 years (vs. 5-7 years) 1.64** (1.14-2.36) 1.07 (0.84-1.37) 1.13 (0.54-2.38) Age 11-14 years (vs. 5-7 years) 1.27* (0.96-1.68) 1.18* (0.98-1.44) (0.79-2.61) 1.43 Male vs. female 1.27 (0.95-1.70) 1.54# (1.26-1.90) 1.99* (1.06-3.74) Higher parental education" 0.70 (0.35-1.41) 0.91 2.47 (0.77-7.93) (0.60-1.39) Low birth weight (20 m2 0.78 (0.58-1.06) 0.97 (0.78-1.20) 0.69 (0.36-1.30) Child shared bedroom 1.19 (0.83-1.70) 1.42** (1.09-1.84) (0.60-2.76) 1.28 Dampness or visible mold 0.57* (0.31-1.07) (0.55-1.58) 0.94 (0.13-2.96) 0.62 District or central heating 0.44* (0.24-0.84) (0.53-1.50) 0.89 (0.11-2.58) 0.54 Heating with coke/coal/briquettes 0.61 (0.60-2.02) 1.10 (0.29-1.29) (0.22-7.69) 1.30 Heating with gas 1.35* (0.97-1.88) (0.67-1.08) 0.85 (0.50-2.40) 1.09 Child's room near main street/industry (0.80-1.46) 1.08 (0.74-1.12) 0.91 (0.42-1.46) 0.78 Wall-to-wall carpet in child's room 0.99 (0.74-1.32) 1.14 (0.93-1.40) 0.68 (0.37-1.27) Current or prior ETS exposure at home (0.40-1.89) 0.87 (0.86-2.31) 1.41 (0.33-6.78) 1.48 Mother smoked during pregnancy 1.06 (0.77-1.45) 0.88 (0.71-1.10) (0.30-1.46) 0.66 Contactwith cats (0.62-1.56) 0.98 1.58** (1.13-2.19) (0.33-2.86) 0.97 Child ever attended day-care center Geographic area 1.15 (0.79-1.67) (0.75-1.22) 0.95 4.40' (1.84-10.5) Bitterfeld vs. Zerbst, adjustedc (0.77-1.59) 1.11 (0.86-1.36) 1.08 4.51# (1.95-10.4) Bitterfeld vs. Zerbst, crude 1.69** (1.21-2.36) 1.52# (1.20-1.92) 1.97 (0.78-4.99) Hettstedt vs. Zerbst, adjustedc 1.73** (1.25-2.39) 1.56' (1.24-1.96) (0.82-5.08) 2.04 Hettstedt vs. Zerbst, crude

Eczema (n= 1,780) Cl Adj OR 0.93 (0.62-1.39) 1.08 (0.73-1.60) (0.67-1.25) 0.91 1.32* (0.95-1.83) 0.27* (0.08-0.89) 0.82 (0.52-1.29) 1.49* (1.08-2.08) 0.83 (0.51-1.34) 0.81 (0.48-1.38) (0.93-1.89) 1.33 0.85 (0.58-1.25) 0.85 (0.60-1.20) 1.23 (0.82-1.84) 1.04 (0.45-2.41) 0.94 (0.41-2.20) 0.90 (0.33-2.43) (0.58-1.32) 0.88 (0.72-1.41) 1.01 1.06 (0.77-1.48) 0.70 (0.27-1.80) 1.02 (0.71-1.46) (0.66-2.00) 1.15 1.42* 1.39 1.52* 1.54*

(0.94-2.15) (0.93-2.06) (1.03-2.24) (1.05-2.26)

ETS, environmental tobacco smoke. &Education of father or mother was at least 12 years. bAtopic diseases (asthma, hay fever, eczema, other allergy) in at least one parent. CAdjusted for potential predictors. *p