Short-term effects of air pollution on daily asthma-related emergency department visits in an industrial city

BACKGROUND

Epidemiological studies from Europe and North America have provided evidence that exposure to air pollution can aggravate symptoms in asthmatic patients.

METHODS

Daily number of AEDv, air pollution levels (PM10, PM2.5, SO2, NO2 and CO) and meteorological variables was obtained from Jubail Industrial City, Saudi Arabia, for the period of 2007-11. Data were analyzed using a time-series approach. Relative risks (RRs) were estimated using Poisson regression.

RESULTS

The associations between AEDv and PM10, PM2.5, SO2 and NO2 remained positive and statistically significant after mutual adjustment in the multi-pollutant model.The RR of AEDv increased by 5.4, 4.4, 3.4 and 2.2% per an inter-quartile range increase in SO2 (2.0 ppb), PM2.5 (36 μg/m3), NO2 (7.6 ppb) and PM10 (140 μg/m3), respectively. No significant associations between AEDv and CO were found.

CONCLUSIONS

Current levels of ambient air pollution are associated with AEDv in this industrial setting in the Middle East. Greater awareness of environmental health protection and the implementation of effective measures to improve the quality of air in such settings would be beneficial to public health.

Predictors of human PBDE body burdens for a UK cohort

Human exposure to polybrominated diphenyl ethers (PBDEs) was investigated in a cohort of 20 UK adults along with their anthropometric covariates and relevant properties such as room surveys, lifestyle, diet and activity details. Selected PBDE congeners were measured in matched samples of indoor dust (n = 41), vehicles (n = 8), duplicate diet (n = 24), serum (n = 24) and breast milk (n = 6). Combined exposure estimates via dust and diet revealed total PBDE intakes of 104 to 1,440 pg kg^-1 bw d^-1 for ΣBDEs_3-7 and 1,170 to 17,000 pg kg^-1 bw d^-1 for BDE-209. These adult intakes are well within health reference doses suggested by the European Food Safety Authority (EFSA) and the US EPA. Diet was the primary source of intake of BDE_3-7 congeners for the majority of the cohort, with dust the primary source of BDE-209. Primary sources of PBDE exposure vary between countries and regions with differing fire prevention regulations. Estimated infant exposures (ages 1.5-4.5 years) showed that BDE-99 intake for one of the households did not meet EFSA's recommended margin of exposure, a further two households had borderline PBDE exposures for high level dust and diet intake. Males and those having a lower body fat mass had higher serum BDE-153. Higher meat consumption was significantly correlated with higher BDEs_3-7 in serum. A reduction in dietary BDEs_3-7 would therefore result in the greatest reduction in BDE-99 exposure. Rooms containing PUF sofas or armchairs over 20 years old had more BDEs_3-7 in their dust, and rooms with carpets or rugs of that age had higher dust BDE-209. Dusting rooms more frequently resulted in significantly lower concentrations of all major congeners in their dust. Correlation between BDE-209 body burden and dust or diet exposure was limited by its low bioaccessibility. Although vehicle dust contained the highest concentrations of BDEs_3-7 and BDE-209, serum BDEs_3-7 correlated most strongly with bedroom dust.

Modeling Seasonal and Spatiotemporal Variation: The Example of Respiratory Prescribing

Many measures of chronic diseases, including respiratory disease, exhibit seasonal variation together with residual correlation between consecutive time periods and neighboring areas. We demonstrate a strategy for modeling data that exhibit both seasonal trend and spatiotemporal correlation, using an application to respiratory prescribing. We analyzed 55 months (2002-2006) of prescribing data from the northeast of England, in the United Kingdom. We estimated the seasonal pattern of prescribing by fitting a dynamic harmonic regression (DHR) model to salbutamol prescribing in relation to temperature. We compared the output of DHR models to static sinusoidal regression models. We used the DHR-fitted values as an offset in mixed-effects models that aimed to account for the remaining spatiotemporal variation in prescribing rates. As diagnostic checks, we assessed spatial and temporal correlation separately and jointly. Our application of a DHR model resulted in a better fit to the seasonal variation of prescribing than was obtained with a static model. After adjusting for the fitted values from the DHR model, we did not detect any remaining spatiotemporal correlation in the model's residuals. Using a DHR model and temperature data to account for the periodicity of prescribing proved to be an efficient way to capture its seasonal variation. The diagnostic procedures indicated that there was no need to model any remaining correlation explicitly.

Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and (208)Pb/(206)Pb, (207)Pb/(206)Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5-8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2-3 years for molars, first 1-2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2µgPb/g) with (208)Pb/(206)Pb (mean ±2σ: 2.126-2.079) (208)Pb/(206)Pb (mean ±2σ: 0.879-0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM10, PM2.5) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4µgPb/g) with (208)Pb/(206)Pb (mean ±2σ: 2.145-2.117) (208)Pb/(206)Pb (mean ±2σ: 0.898-0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1-2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot study confirms that laser ablation Pb isotope analysis of deciduous teeth, when carried out in conjunction with histological analysis, permits a reconstruction of the timing, duration and source of exposure to Pb during early childhood. With further development, this approach has the potential to study larger cohorts and appraise environments where the levels of exposure to Pb are much higher.

Determinants of childhood lead exposure in the postleaded petrol era: The Tooth Fairy cohort from Newcastle upon Tyne

Lead is an environmental contaminant causing irreversible health effects in children. We used dentine lead levels as a measure of early-life lead exposure and explored determinants of lead exposure in children living in Newcastle upon Tyne, a historically industrialised UK city, in a cohort born since legislation was introduced to remove lead from petrol, paint and water pipes. The "Tooth Fairy study" cohort comprised 69 children aged 5-8 years. We collected upper deciduous incisors from children and questionnaire data from their parents in 2005. We measured lead levels in pre- and postnatal enamel and dentine using laser ablation inductively coupled plasma mass spectrometry, and assessed associations between dentine lead levels and residential, dietary, lifestyle and socio-economic characteristics. Dentine lead levels were low (mean 0.26 μg/g, range 0.06-0.77); however, we observed considerable variability in dentine lead levels within and between children suggestive of differing exposure levels and/or exposure sources across this population. Variables earlier documented to be associated with childhood lead levels were not found to be significant determinants of dentine lead levels in this study. Exposure pathways should continue to be investigated to enable targeted interventions and prevention of lead-induced health impacts in vulnerable populations.

PBDEs and PBBs in human serum and breast milk from cohabiting UK couples

Concentrations of PBDEs and PBBs were measured in matched blood and breast milk samples from 10 UK couples collected in 2011-12. These data are the first measurements in human serum from the UK since the 2004 EU ban on all uses of the penta-and octa-BDE formulations and the 2008 ban on the use of the deca-BDE formulation in some applications. Serum ∑PBDE tri-hepta concentrations ranging from 1.0 to 16 ng g(-1) lipid weight, with median 4.0 ng g(-1) lw were measured. Breast milk ∑PBDE tri-hepta concentrations ranged from 1.3 to 21 ng g(-1) lw, with median 5.7 ng g(-1) lw. Couples had similar serum congener concentrations unless one of them frequently stayed away from home for work (different diet and dust exposures) or one had occupational exposure to foams and furnishings or electronics. BB-153 were measured above LOD in 40% of sera and 100% of breast milks samples, with median concentrations of 0.04 and 0.06, and maximums of 0.91 and 0.79 ng g(-1) lw respectively. Concentrations in this study indicated a modest decrease from pre-ban levels reported for the UK. BDE-209 was detected above the limit of detection (LOD) in 15% of sera and 83% of breast milks, with ranges <1.2-20 and <0.2-1.0 ng g(-1) lw respectively. Average daily infant intakes were estimated at 17, 5, 5 and 3 ng kg(-1) bw for BDE-47,-99,-153 and -209 respectively, all well below relevant US-EPA threshold reference dose values (RfDs).

Association between respiratory prescribing, air pollution and deprivation, in primary health care

BACKGROUND

We investigated the association between respiratory prescribing, air quality and deprivation in primary health care. Most previous studies have used data from secondary and tertiary care to quantify air pollution effects on exacerbations of asthma and chronic obstructive pulmonary disease (COPD). However, these outcomes capture patients who suffer from relatively severe symptoms.

METHODS

This is a population-based ecological study. We analysed respiratory medication (salbutamol) prescribed monthly by 63 primary care practices, UK. Firstly, we captured the area-wide seasonal variation in prescribing. Then, using the area-wide variation in prescribing as an offset, we built a mixed-effects model to assess the remaining variation in relation to air quality and demographic variables.

RESULTS

An increase of 10 μg/m(3) in ambient PM10 was associated with an increase of 1% (95% CI: 0.1-2%) in salbutamol prescribing. An increase of 1 SD in income and employment deprivation was associated with an increase of 20.5% (95% CI: 8.8-33.4%) and 14.7% (95% CI: 4.3-26.2%) in salbutamol prescribing rate, respectively.

CONCLUSIONS

The study provides evidence that monthly respiratory prescribing in primary care is a useful indicator of the extent to which air pollution exacerbates asthma and COPD symptoms. Respiratory prescribing was higher on deprived populations.

No improvement in socioeconomic inequalities in birthweight and preterm birth over four decades: a population-based cohort study

BACKGROUND

Birthweight and gestational age are associated with socioeconomic deprivation, but the evidence in relation to temporal changes in these associations is sparse. We investigated changes in the associations between socioeconomic status (SES) and birthweight and gestational age in Newcastle upon Tyne, North of England, during 1961-2000.

METHODS

We used population-based data from hospital neonatal records on all singleton births to mothers resident in Newcastle (births with complete covariate information n = 113,182). We used linear regression to analyse the associations between neighbourhood SES and birthweight over the entire 40-year period and by decade, and logistic regression for associations with low birthweight (LBW) and preterm birth, adjusting for potential confounders.

RESULTS

There was a significant interaction between SES and decade of birth for birthweight (p = 0.028) and preterm birth (p < 0.001). Socioeconomic gradients were similar in each decade for birthweight outcomes, but for preterm birth, socioeconomic disparities were more evident in the later decades [for 1961-70, odds ratio (OR) was 1.1, 95% CI 0.9, 1.3, for the most deprived versus the least deprived quartile, while for 1991-2000, the corresponding OR was 1.5, 95% CI 1.3, 1.7]. In each decade, there was a significant decrease in birthweight adjusted for gestational age for the most deprived compared to the least deprived SES group [1961-1970: -113.4 g (95% CI-133.0, -93.8); 1991-2000: -97.5 g (95% CI-113.0, -82.0)], while there was a significant increase in birthweight in each SES group over time.

CONCLUSIONS

Socioeconomic inequalities did not narrow over the four decades for birthweight and widened for preterm birth. Mean birthweight adjusted for gestational age increased in all socioeconomic groups, suggesting an overall increase in fetal growth.

Maternal exposure to particulate air pollution and term birth weight: a multi-country evaluation of effect and heterogeneity

BACKGROUND

A growing body of evidence has associated maternal exposure to air pollution with adverse effects on fetal growth; however, the existing literature is inconsistent.

OBJECTIVES

We aimed to quantify the association between maternal exposure to particulate air pollution and term birth weight and low birth weight (LBW) across 14 centers from 9 countries, and to explore the influence of site characteristics and exposure assessment methods on between-center heterogeneity in this association.

METHODS

Using a common analytical protocol, International Collaboration on Air Pollution and Pregnancy Outcomes (ICAPPO) centers generated effect estimates for term LBW and continuous birth weight associated with PM(10) and PM(2.5) (particulate matter ≤ 10 and 2.5 µm). We used meta-analysis to combine the estimates of effect across centers (~ 3 million births) and used meta-regression to evaluate the influence of center characteristics and exposure assessment methods on between-center heterogeneity in reported effect estimates.

RESULTS

In random-effects meta-analyses, term LBW was positively associated with a 10-μg/m3 increase in PM10 [odds ratio (OR) = 1.03; 95% CI: 1.01, 1.05] and PM(2.5) (OR = 1.10; 95% CI: 1.03, 1.18) exposure during the entire pregnancy, adjusted for maternal socioeconomic status. A 10-μg/m3 increase in PM(10) exposure was also negatively associated with term birth weight as a continuous outcome in the fully adjusted random-effects meta-analyses (-8.9 g; 95% CI: -13.2, -4.6 g). Meta-regressions revealed that centers with higher median PM(2.5) levels and PM(2.5):PM(10) ratios, and centers that used a temporal exposure assessment (compared with spatiotemporal), tended to report stronger associations.

CONCLUSION

Maternal exposure to particulate pollution was associated with LBW at term across study populations. We detected three site characteristics and aspects of exposure assessment methodology that appeared to contribute to the variation in associations reported by centers.

Defining GP practice areas based on true service utilisation

Where patients who are registered with a general practice actually live (the service utilisation area) often differ from what GPs consider their practice boundaries or catchment area to be, as well as from administrative boundaries. A key aim of primary care commissioners is to allocate resources efficiently and to locate services in such a way that access is convenient for patients. To achieve this robust understanding of practice service utilisation areas and the overlap between practices and administrative areas are essential. We used kernel analysis of the postcodes of over 400,000 registered patients to define GP service utilisation areas. We estimated service utilisation for each of 64 practices for a period of five years (2002-2006) exploring the areas in which 99%, 98%, and 95% of registered patients were expected to live. These service utilisation areas were not coterminous with other practices or with administrative boundaries. We present a simple analytical method to define GP catchment areas that captures the true service utilisation area and identifies the extent of overlap. This is a practical tool that can assist health care commissioning.

Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 μm diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers.

Particulate matter exposure during pregnancy is associated with birth weight, but not gestational age, 1962-1992: a cohort study

BACKGROUND

Exposure to air pollutants is suggested to adversely affect fetal growth, but the evidence remains inconsistent in relation to specific outcomes and exposure windows.

METHODS

Using birth records from the two major maternity hospitals in Newcastle upon Tyne in northern England between 1961 and 1992, we constructed a database of all births to mothers resident within the city. Weekly black smoke exposure levels from routine data recorded at 20 air pollution monitoring stations were obtained and individual exposures were estimated via a two-stage modeling strategy, incorporating temporally and spatially varying covariates. Regression analyses, including 88,679 births, assessed potential associations between exposure to black smoke and birth weight, gestational age and birth weight standardized for gestational age and sex.

RESULTS

Significant associations were seen between black smoke and both standardized and unstandardized birth weight, but not for gestational age when adjusted for potential confounders. Not all associations were linear. For an increase in whole pregnancy black smoke exposure, from the 1(st) (7.4 μg/m(3)) to the 25(th) (17.2 μg/m(3)), 50(th) (33.8 μg/m(3)), 75(th) (108.3 μg/m(3)), and 90(th) (180.8 μg/m(3)) percentiles, the adjusted estimated decreases in birth weight were 33 g (SE 1.05), 62 g (1.63), 98 g (2.26) and 109 g (2.44) respectively. A significant interaction was observed between socio-economic deprivation and black smoke on both standardized and unstandardized birth weight with increasing effects of black smoke in reducing birth weight seen with increasing socio-economic disadvantage.

CONCLUSIONS

The findings of this study progress the hypothesis that the association between black smoke and birth weight may be mediated through intrauterine growth restriction. The associations between black smoke and birth weight were of the same order of magnitude as those reported for passive smoking. These findings add to the growing evidence of the harmful effects of air pollution on birth outcomes.

Sex differences in the prevalence of congenital anomalies: a population-based study

BACKGROUND

Limited data is available concerning the sex distribution of various congenital anomaly subtypes. This study investigated sex differences in the prevalence of congenital anomalies, overall and by subtype, using high quality population-based data from the North of England.

METHODS

Information on congenital anomalies occurring among singleton pregnancies during 1985-2003 were extracted from the Northern Congenital Abnormality Survey (NorCAS). Anomalies were categorized by groups, subtypes, and syndromes according to the European Surveillance of Congenital Anomalies guidelines. Relative risks (RRs) comparing the prevalences in males to that in females were calculated for a range of congenital anomaly subtypes.

RESULTS

A total of 12,795 eligible cases of congenital anomaly were identified during the study period, including 7019 (54.9%) males and 5776 (45.1%) females. Overall, male fetuses were significantly more prevalent in pregnancies affected by a congenital anomaly than female fetuses (RR, male vs. female = 1.15; 95% confidence interval [CI], 1.11-1.19), but there was significant heterogeneity between subtypes (p < 0.001). Forty-four of 110 (40%) unique subtypes were at least 40% more prevalent in males than females, with affected subtypes occurring across all major anomaly groups. Thirteen of 110 (12%) unique subtypes were at least 40% more prevalent in females than males, but the female-biased RR of a neural tube defect was less pronounced than previously reported (RR = 0.84; 95% CI, 0.73-0.95).

CONCLUSION

This study adds to the growing evidence of sex-specific differences in the prevalence of a wide range of congenital anomaly subtypes.

Ambient air pollution and congenital heart disease: a register-based study

Maternal exposure to ambient air pollution has increasingly been linked to adverse pregnancy outcomes. The evidence linking this exposure to congenital anomalies is still limited and controversial. This case-control study investigated the association between maternal exposure to ambient particulate matter with aerodynamic diameter less than 10 μm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxide, nitric oxide (NO), ozone (O(3)), and carbon monoxide (CO) and the occurrence of congenital heart disease in the population of Northeast England (1993-2003). Each case and control was assigned weekly average (weeks 3-8 of pregnancy) of pollutant levels measured by the closest monitor to the mother's residential postcode. Using exposure as both continuous and categorical variables, logistic regression models were constructed to quantify the adjusted odds ratios of exposure to air pollutants and the occurrence of each outcome group. We found exposure to CO and NO to be associated with ventricular septal defect and cardiac septa malformations. CO was also associated with congenital pulmonary valve stenosis and NO with pooled cases of congenital heart disease and tetralogy of Fallot. Findings for SO(2), O(3) and PM(10) were less consistent.

Association between maternal exposure to ambient air pollution and congenital heart disease: A register-based spatiotemporal analysis

Recent studies have linked maternal exposure to air pollution with a range of adverse pregnancy outcomes. However, the available evidence linking this exposure to congenital anomalies is still limited and controversial. The present case-control study tested the hypothesis that maternal exposure to ambient black smoke and sulfur dioxide is a risk factor for the occurrence of congenital heart disease. The authors used registry-based data on congenital heart disease for the population of the northeast of England in 1985-1996. A 2-stage spatiotemporal model was developed to predict weekly black smoke and sulfur dioxide levels at each maternal place of residence. Controls were frequency-matched to cases by year of birth (control-to-case ratio of 4:1). Two sets of analyses were performed, using predicted mean values of exposure and 1,000 simulated scenarios of exposure. The analyses were adjusted for birth year, socioeconomic status, infant sex, season of conception, and degree of urbanity. The authors found a weak association between maternal exposure to black smoke and congenital malformations of cardiac chambers and connections only when using exposure as a continuous variable. When the authors used quartiles of exposure, odds ratios did not show a dose-response relation for consecutive quartiles. For sulfur dioxide, the results were not indicative of any association.

Stillbirth and infant mortality in singletons by cause of death, birthweight, gestational age and birthweight-for-gestation, Newcastle upon Tyne 1961-2000

The dramatic reduction observed in stillbirth and infant mortality over the last few decades has not been assessed by both birthweight and gestation. We have explored temporal changes in stillbirth and infant mortality in Newcastle upon Tyne, UK, by cause of death, birthweight, gestational age, birthweight standardised for gestation and infant sex during 1961-2000. We included 131 044 singleton births to mothers resident in Newcastle, including 1342 stillbirths and 1620 infant deaths. Cause-, birthweight-, gestational age- and birthweight-for-gestation-specific stillbirth (per 1000 total births) and infant mortality (per 1000 livebirths) rates were compared between 1961-80 and 1981-2000 and between individual consecutive decades. Between 1961 and 2000, total stillbirth and infant mortality rates declined dramatically from 23.4 to 4.7 per 1000 total births and from 25.7 to 5.9 per 1000 livebirths, respectively. Rates fell continuously during the first two study decades; however, from 1981-90 to 1991-2000 the decline was not statistically significant. Between 1961-80 and 1981-2000, both stillbirth and infant mortality significantly declined in all birthweight and gestational age categories and for most leading causes of death. Although the population mean birthweight during 1981-2000 [3304 g (SD +/- 569)] was significantly higher than during 1961-80 [3255 g (SD +/- 572)] (P < 0.0001), the lowest stillbirth and infant mortality rates in 1981-2000 were consistently at about 1 SD above the mean birthweight, with mortality rates increasing for babies with lower or higher weight-for-gestation. Declines in stillbirth and infant mortality in Newcastle were associated with reductions in birthweight- and gestational age-specific mortality rates and occurred in most cause-specific groups of death.

COPD prevalence and its association with occupational exposures in a general population

The aim of this study was to ascertain the population prevalence of chronic obstructive pulmonary disease (COPD) in an area with past heavy industry and to establish the relative contributions of occupational and other risk factors. We investigated respiratory symptoms and the prevalence of spirometrically-defined COPD in a population-based study in North-East England (UK) between 2002 and 2004. Questionnaires were posted to 6,000 males and 6,000 females, 45-69 yrs of age, who were randomly selected from a primary care database (response rate 64%, n = 7,566). Spirometric measurements were performed on 845 randomly selected responders. We defined COPD by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) II criteria. The prevalence of respiratory symptoms was 55%. Symptoms were strongly associated with smoking, occupational exposures and hay fever. COPD was present in 10% of subjects. Its presence was significantly associated with occupational exposures, smoking and hay fever. COPD is common in North-East England. Respiratory effects of occupational exposures can be detected within the general population: there were clear associations between occupational exposures and respiratory symptoms. The association with COPD was more marked in females.

No association between ambient particulate matter exposure during pregnancy and stillbirth risk in the north of England, 1962-1992

OBJECTIVES

Research evidence suggests that exposure to ambient air pollutants can adversely affect the growth and development of the foetus and infant survival. Much less is known regarding the potential for an association between black smoke air pollution and stillbirth risk. This potential association was examined using data from the historical cohort UK Particulate Matter and Perinatal Events Research (PAMPER) study.

METHODS

Using data from paper-based neonatal records from the two major maternity hospitals in Newcastle upon Tyne (UK), a birth record database of all singletons born during 1961-1992 to mothers resident in the city was constructed. Weekly black smoke levels were obtained from routine data recorded at 20 air pollution monitoring stations over the study period. A two-stage statistical modelling strategy was used, incorporating temporally and spatially varying covariates to estimate black smoke exposure during each trimester and for the whole pregnancy period for each individual pregnancy. Conditional logistic regression models, with stratification on year of birth, were used to assess potential associations between black smoke exposures in pregnancy and stillbirth risk.

RESULTS

The PAMPER database consists of 90,537 births, between 1962 and 1992, with complete gestational age and residential address information, of which 812 were stillborn. There was no association between black smoke exposures in any trimester or across whole pregnancy and risk of stillbirth. Adjustment for potential confounders did not alter these results.

CONCLUSIONS

While black smoke in pregnancy is likely to be related to other pregnancy outcomes, our findings do not suggest that black smoke air pollution exposure during pregnancy increases the risk of stillbirth.

Maternal exposure to ambient air pollutants and risk of congenital anomalies

Studies have suggested an association between maternal exposure to ambient air pollution and risk of congenital anomaly. The aim of this study is to investigate the association between exposure to black smoke (BS; particulate matter with aerodynamic diameter <4 microg/m(3)) and sulphur dioxide (SO(2)) during the first trimester of pregnancy and risk of congenital anomalies. We used a case-control study design among deliveries to mothers resident in the UK Northern health region during 1985-1990. Case data were ascertained from the population-based Northern Congenital Abnormality Survey and control data from national data on all births. Data on BS and SO(2) from ambient air monitoring stations were used to average the total pollutant exposure during the first trimester of pregnancy over the daily readings from all monitors within 10 km of the mother's residence. Logistic regression models estimated the association via odds ratios. A significant but weak positive association was found between nervous system anomalies and BS (OR=1.10 per increase of 1000 microg/m(3) total BS; 95% CI: 1.03, 1.18), but not with other anomaly subtypes. For SO(2), a significant negative association was found with congenital heart disease combined and patent ductus arteriosus: OR significantly <1 for all quartiles relative to the first quartile. The relationship between SO(2) levels and other anomaly subtypes was less clear cut: there were either no significant associations or a suggestion of a U-shaped relationship (OR significantly <1 for moderate compared to lowest levels, but not with high SO(2) levels). Overall, maternal exposure to BS and SO(2) in the Northern region had limited impact on congenital anomaly risk. Studies with detailed exposure assessment are needed to further investigate this relationship.

Views on chemical safety information and influences on chemical disposal behaviour in the UK

This study examined how groups representing four tiers in the chemical supply chain (manufacturers, vendors, workers and consumers) understood safety information, and the factors that influenced disposal behaviour. Data from seven, semi-structured, focus groups was analysed both qualitatively (textual analysis) and quantitatively (network analysis). Such combined analytical methods enabled us to achieve both detailed insights into perceptions and behaviour and an objective understanding of the prevailing opinions that occurred within and between the focus group discussions. We found issues around awareness, trust, access and disposal behaviours differed between groups within the supply chain. Participants from the lower tiers perceived chemical safety information to be largely inaccessible. Labels were the main source of information on chemical risks for the middle and bottom tiers of the supply chain. Almost all of the participants were aware of the St Andrew's Cross and skull and crossbones symbols but few were familiar with the Volatile Organic Compound logo or the fish and tree symbol. Both the network and thematic analysis demonstrated that whilst frequent references to health risks associated with chemicals were made environmental risks were usually only articulated after prompting. It is clear that the issues surrounding public understanding of chemical safety labels are highly complex and this is compounded by inconsistencies in the cognitive profiles of chemical users. Substantially different cognitive profiles are likely to contribute towards communication difficulties between different tiers of the supply chain. Further research is needed to examine the most effective ways of communicating chemical hazards information to the public. The findings demonstrate a need to improve and simplify disposal guidance to members of the public, to raise public awareness of the graphic symbols in the CHIP 3.1, 2005 regulations and to improve access to disposal guidance.

Descriptive epidemiology of congenital heart disease in Northern England

Congenital heart disease (CHD) is the most prevalent group of congenital anomalies. There is considerable variation in the reported epidemiology of CHD, mainly attributable to methodological differences. Using register-based data, the current study describes the epidemiology of CHD in a geographically well-defined population of the North of England during 1985-2003. The total prevalence of CHD was 85.9 per 10 000 births and terminations of pregnancy for fetal anomaly. Livebirth prevalence was 79.7 per 10 000 livebirths. Both total and livebirth prevalence increased during the study period. Ninety-two per cent of affected pregnancies resulted in a livebirth, 5% were terminated, 2% resulted in a stillbirth, and 1% in a late miscarriage. Almost a quarter (23%) of cases had one or more coincident anomalies of other organs, with chromosomal abnormalities the most frequent group. A total of 89.2% of cases survived to 1 year and the survival improved during the study period. This population-based study has demonstrated an increasing trend in both prevalence and survival among children with CHD.

Temporal changes in key maternal and fetal factors affecting birth outcomes: a 32-year population-based study in an industrial city

Background

The link between maternal factors and birth outcomes is well established. Substantial changes in society and medical care over time have influenced women's reproductive choices and health, subsequently affecting birth outcomes. The objective of this study was to describe temporal changes in key maternal and fetal factors affecting birth outcomes in Newcastle upon Tyne over three decades, 1961–1992.

Methods

For these descriptive analyses we used data from a population-based birth record database constructed for the historical cohort Particulate Matter and Perinatal Events Research (PAMPER) study. The PAMPER database was created using details from paper-based hospital delivery and neonatal records for all births during 1961–1992 to mothers resident in Newcastle (out of a total of 109,086 singleton births, 97,809 hospital births with relevant information). In addition to hospital records, we used other sources for data collection on births not included in the delivery and neonatal records, for death and stillbirth registrations and for validation.

Results

The average family size decreased mainly due to a decline in the proportion of families with 3 or more children. The distribution of mean maternal ages in all and in primiparous women was lowest in the mid 1970s, corresponding to a peak in the proportion of teenage mothers. The proportion of older mothers declined until the late 1970s (from 16.5% to 3.4%) followed by a steady increase. Mean birthweight in all and term babies gradually increased from the mid 1970s. The increase in the percentage of preterm birth paralleled a two-fold increase in the percentage of caesarean section among preterm births during the last two decades. The gap between the most affluent and the most deprived groups of the population widened over the three decades.

Conclusion

Key maternal and fetal factors affecting birth outcomes, such as maternal age, parity, socioeconomic status, birthweight and gestational age, changed substantially during the 32-year period, from 1961 to 1992. The availability of accurate gestational age is extremely important for correct interpretation of trends in birthweight.

Concentration of polybrominated diphenyl ethers (PBDEs) in household dust from various countries

Seven polybrominated diphenyl ether (PBDE) congeners were measured in the particulate fraction (<2mm) of household dust samples (n=40), collected in four different countries (Australia, Germany, Great Britain, and United States). Dust samples from Germany contained the lowest concentrations of total PBDEs (median: 74 ng/g, range: 17-550 ng/g dust). Australian dust contained the second lowest concentration (median: 1200 ng/g, range: 500-13,000 ng/g dust). The dust from the United States and Great Britain contained the highest measured amounts of total PBDEs (US median: 4200 ng/g dust, range: 520-29,000 ng/g; Great Britain median: 10,000 ng/g, range: 950-54,000 ng/g). Daily intake of PBDEs has been estimated from published reference values on daily dust intake rates. The highest daily intake of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) found was in the United States (<1-330 ng/day) and the lowest was in Germany (<1-2 ng/day). The PBDE congeners present in commercially available pentabromodiphenyl ether were the highest in concentration in the United States, and the congener distribution was similar to that of the technical preparation (i.e., 2,2',4,4',5-pentabromodiphenyl ether [BDE-99] was similar in concentration to that of BDE-47). We conclude that further studies are required to investigate human indoor exposure to PBDEs across countries and to determine the risk factors related to indoor design factors.

Does the effect of air pollution on pregnancy outcomes differ by gender? A systematic review

Gender is known to influence pregnancy outcomes. Recent studies have reported an association between air pollution exposure and adverse pregnancy outcomes, but gender differences have not been considered. In order to assess the current evidence of the interactive effects between gender and air pollution on pregnancy outcomes we undertook a systematic literature review. Using a comprehensive list of keywords, English language articles published between 1966 and 2005 were retrieved from major databases. Additional information on gender was obtained from the study authors. Studies were included if they contained well-defined measurements of ambient air pollutants, investigated pregnancy outcomes and reported estimates by gender. In total 11 studies were included. The quality of the studies was assessed using the framework in Systematic Reviews in Health Care Meta-analysis in context and Bracken's Guidelines. Of the 11 studies, four evaluated low birth weight (LBW); one each evaluated very low birth weight and fetal growth and six examined preterm birth (PTB). Females were at higher risk of LBW: adjusted odds ratios (AOR) ranged from 1.07 to 1.62. Males were at higher risk for PTB: AORs ranged from 1.11 to 1.20. In addition, there was some evidence to suggest that the effect of air pollution on LBW is differential by gender; however, the evidence was available only from four studies. This is the first systematic review to consider gender effect. Further high quality studies are needed to establish whether these findings prevail.

Enabling factors and barriers for the use of health impact assessment in decision-making processes

OBJECTIVE

To identify key stakeholders' views of factors that may enable or limit the use of health impact assessment (HIA) in the decision-making processes within their organizations.

METHODS

In-depth interviews were carried out with 14 key informants from local and regional stakeholder organizations.

SETTING

North East of England, 2005.

RESULTS

Three emergent themes were identified: leadership in HIA; integration of HIA with existing organizational structures; and joint working between key stakeholder organizations.

CONCLUSIONS

With the exception of a 'leadership vacuum' that had not been described previously, the present findings on factors that enable or limit the use of HIA in decision making by organizations in the region are consistent with those reported previously in the literature. In the absence of a nationally defined regulatory and organizational framework for HIA practice, key stakeholders' views on factors that promote or hinder the use of HIA in the decision-making process of their organizations may be pivotal in advancing HIA practice in the region.

Identifying contemporary and historic sources of soil polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in an industrial urban setting

A study of soil polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) concentrations was undertaken in the vicinity of a municipal solid waste incinerator (MSWI) in Newcastle upon Tyne as a result of concerns raised by local residents about potential contamination from fugitive and stack emissions. The study area was divided into four sectors (north-east (NE), south-east (SE), north-west (NW) and south-west (SW)) around the MSWI, and sampling sites were located up to a distance of 2.25 km. Based on air dispersion modelling, the sampling density was four times greater in the NE (downwind) sector compared to the SW (upwind) direction, and twice as great in the NW and SE sectors. PCDD/F concentrations found in soil samples ranged from 6 to 1911 ng I-TEQ/kg DW with a median of 32 ng I-TEQ/kg DW. There was no evidence of elevated concentrations downwind of the MSWI compared to other directions, nor of any trend in concentration at increasing distance from the MSWI. We concluded, therefore, that the MSWI fugitive and stack emissions were not a major source of PCDD/F contamination. Analysis of PCDD/F homologue profiles showed that samples exhibiting furan-dominated and OCDD-dominated profiles and a profile characteristic of the MSWI ash occurred in distinct clusters. Those samples showing the furan-dominated profile had the largest PCDD/F concentrations measured as I-TEQ, followed by samples with the incinerator profile, the deposition profile, and the OCDD-dominated profile. We identified some contamination hotspots located in the SW and SE sampling sectors (upwind of the MSWI), and potential sources for these hotspots were sought by using historic land use data from maps of the locality dating back to 1856. We concluded that the cluster of very high concentrations of PCDD/F in soils showing the furan homologue profile were most likely to have resulted from the disposal of graphite electrode sludges from brine electrolysis carried out at a chemical works between the 1890s and the 1930s.

Does living near heavy industry cause lung cancer in women? A case-control study using life grid interviews

BACKGROUND

The incidence of lung cancer among women is high in the highly industrialised area of Teesside in north-east England. Previous research has implicated industrial pollution as a possible cause. A study was undertaken to investigate whether prolonged residence close to heavy industry is associated with lung cancer among women in Teesside.

METHODS

Two hundred and four women aged <80 years with incident primary lung cancer and 339 age matched community controls were recruited to a population based case-control study. Life course residential, occupational, and active and passive smoking histories were obtained using an interviewer administered questionnaire.

RESULTS

The age adjusted odds ratio (OR) for lung cancer among people living >25 years v 0 years near (within 0-5 km) heavy industry in Teesside was 2.13 (95% CI 1.34 to 3.38). After adjustment for confounding factors the OR was 1.83 (95% CI 0.82 to 4.08) for >25 years or 1.10 (95% CI 0.96 to 1.26) for an additional 10 years living near industry. ORs were similar after residence near heavy industry outside Teesside was also included, and when latency was allowed for by disregarding residential exposures within the last 20 years. Adjustment for active smoking had the greatest effect on the OR.

CONCLUSIONS

This population based study using life grid interviews for life course exposure assessment has addressed many deficiencies in the design of previous studies. The findings support those in most of the international literature of a modestly raised risk of lung cancer with prolonged residence close to heavy industry, although the confidence intervals were wide. The effect of air pollution on the incidence of lung cancer merits continued study.

Metal contamination of urban soils in the vicinity of a municipal waste incinerator: one source among many

Concern from local residents about possible contamination with metals and PCDD/F (dioxins and furans) from fugitive and stack emissions from the Byker municipal solid waste incinerator in Newcastle upon Tyne led the City Council to initiate a study of the concentration of these pollutants in soils. We report here the results for the metals and arsenic. Soils were sampled at distances up to 2.25 km from the incinerator stack. The intensity of sampling in concentric zones was four times greater in the northeast (down-wind) direction, and twice as great in the northwest and southeast directions, compared to the southwest (up-wind) direction. In total 163 samples were collected and analyzed for total As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. Concentrations were generally elevated above background levels, but were typical of those found in other urban areas. For As, Cd, Cu, Hg, Pb, and Zn, contamination hotspots were identified. These were spread throughout the sampling area, and there was no evidence of greater concentrations down-wind of the incinerator compared to other directions, nor of any trend in concentration at increasing distance from the incinerator. We concluded that metal contamination resulting from the incinerator could not be detected in an environment with generally elevated concentrations. Potential sources for many of the hotspots of contamination were identified in a survey of historic land use based on maps of the locality dating back to 1856. Detailed investigations of particular areas with serious contamination will now be undertaken by the local authorities using the CLEA (Contaminated Land Exposure Assessment) model.

Does long term residency near industry have an impact on the body burden of polychlorinated dibenzo-p-dioxins, furans, and polychlorinated biphenyls in older women?

BACKGROUND

For the retrospective study of environment and health linkages biomarkers of exposure are required. Polychlorinated dibenzo-dioxins and furans (PCDD/F) and polychlorinated biphenyls (PCBs) have been useful markers in some settings. This is the first study of PCDD/F body burden in a population based sample from the UK.

AIMS AND METHODS

The authors aimed to investigate whether long term residents close to a heavy chemical industrial complex (Teesside, UK) had a higher body burden and distinct pattern of PCDD/F and PCBs. We measured current levels of PCDD/F and PCBs in a population based sample of older women (mean 64 years, range 42-79 years). Forty women were recruited, 20 living near (zone A: 0.1-2.7 km) and 20 distant (zone C: 5-40 km) from industry during 2000-03. The authors ascertained occupational exposure to lung carcinogens, residential history, consumption of local produce, breast feeding, diet, and height and weight.

RESULTS

The mean body burden measured on lipid basis in ng/kg for the whole sample was: WHO-TEQ (PCDD/Fs): 29.9, 2378TCDD: 4.0, PCB 118:16200, PCB156: 13100. Body burdens were similar to others reported from industrialised countries, except that mean 2378TCDD was slightly higher. Mean ages, body mass index, and lifelong dietary patterns were similar in both zones. The authors found no significant difference in mean body burden levels between zones A and C before or after adjustment for covariates. All congener patterns were consistent with an urban background pattern, and there was no significant difference between congener compositions in the two zones. The TCDD body burden increased with age with accelerated increments above age 70.

CONCLUSION

Long term residency near heavy and chemical industry did not have an effect on women's body burden of PCDD/Fs and PCBs on Teesside, UK. The body burden of PCDD/F and PCBs was not a suitable biomarker for chronic, non-occupational exposure to industrial air pollution.

Does particulate air pollution contribute to infant death? A systematic review

There is now substantial evidence that both short- and long-term increases in ambient air pollution are associated with increased mortality and morbidity in adults and children. Children's health is particularly vulnerable to environmental pollution, and infant mortality is still a major contributor to childhood mortality. In this systematic review we summarize and evaluate the current level of epidemiologic evidence of an association between particulate air pollution and infant mortality. We identified relevant publications using database searches with a comprehensive list of search terms and other established search methods. We included articles in the review according to specified inclusion criteria. Fifteen studies met our inclusion criteria. Evidence of an association between particulate air pollution and infant mortality in general was inconsistent, being reported from locations with largely comparable pollution levels. There was some evidence that the strength of association with particulate matter differed by subgroups of infant mortality. It was more consistent for postneonatal mortality due to respiratory causes and sudden infant death syndrome. Differential findings for various mortality subgroups within studies suggest a stronger association of particulate air pollution with some causes of infant death. Research is needed to confirm and clarify these links, using the most appropriate methodologies for exposure assessment and control of confounders.

Particulate air pollution and fetal health: a systematic review of the epidemiologic evidence

BACKGROUND

Research on the potential impact of air pollution on the health of adults and children has grown rapidly over the last decade. Recent studies have suggested that air pollution could also be associated with adverse effects on the developing fetus. This systematic review evaluates the current level of epidemiologic evidence on the association between ambient particulate air pollution and fetal health outcomes. We also suggest further research questions.

METHODS

Using database searches and other approaches, we identified relevant publications published between 1966 and 2001 in English. Articles were included if they reported original data on birthweight, gestational age at delivery, or stillbirth related to directly measured nonaccidental exposure to particulate matter.

RESULTS

Twelve studies met the inclusion criteria. There was little consistency in the evidence linking particulate air pollution and fetal outcomes. Many studies had methodologic weaknesses in their design and adjustment for confounding factors. Even in well-designed studies, the reported magnitude of the effects was small and inconsistently associated with exposure at specific stages of pregnancy.

CONCLUSIONS

The currently available evidence is compatible with either a small adverse effect of particulate air pollution on fetal growth and duration of pregnancy or with no effect. Further research should be directed toward clarifying and quantifying these possible effects and generating testable hypotheses on plausible biologic mechanisms.

Integrated Pollution Prevention and Control: a review of health authorities' experience

In August 2000, health authorities in England and Wales became statutory consultees for permits issued to industry by the Environment Agency as part of the implementation of EU directives. This responsibility has since been delegated to Primary Care Trusts. To assess health authority responses to applications made under the Integrated Pollution Prevention and Control (IPPC) regulations, we collected data from public registers during the first 12 months of this new regulatory regime. There was evidence of 27 applications, of which 59 per cent had substantive comments from health authorities. There was wide variation in the length and content. Responses were from Consultants in Communicable Disease Control (57 per cent) or Directors of Public Health (43 per cent). Only two health authorities had a dedicated resource for responding to IPPC applications. Capacity and capability are lacking and require resources invested for consistent, effective public health input to the process of permitting potentially polluting industries.

"It wasn't the plague we expected." Parents' perceptions of the health and environmental impact of opencast coal mining

This paper explores the health and environmental concerns of parents living close to opencast coal mines in the UK and characterises parental risk perceptions in relation to children's asthma status. This qualitative research was undertaken in tandem with an epidemiological investigation aiming to establish whether opencast coal mining adversely affected children's respiratory health. Using a social construction approach, the centrality of health claims in environmental health disputes becomes apparent for a number of claims-makers. We focus on claims of non-activist participants in an epidemiological study, hitherto unknown and unexplored. In all but one case health claims were anticipated rather than realised. No link was found between children's asthma and exacerbation of the condition although some parents of children with asthma had greater concerns during the opencast planning stage. In fact, parents' discourses on children's health largely mirrored the epidemiological findings which showed increased dust, no increase in asthma prevalence but higher rates of general practitioner (GP) consultations for respiratory conditions suggesting that the commonly observed lack of convergence between lay and expert knowledge should not be taken for granted. In spite of this overall lack of an experienced health effect, the sociological data highlight respondents' recognition of the place-specificity of exposures, hence, the reasons why opencast proposals are likely to continue to be met with opposition. Environmental health studies which incorporate epidemiological and social approaches simultaneously have a better chance of arriving at conclusions meaningful to affected communities and facilitate greater understanding of environmental disputes.

Children's respiratory health and daily particulate levels in 10 nonurban communities

We conducted a study to assess the association between the acute respiratory health of children and the levels of particulates in communities near and away from active opencast coal mines. The study enrolled children aged 1-11 years from the general population of five socioeconomically matched pairs of nonurban communities in northern England. Diaries of respiratory events were collected for 1405 children, and information was collected on the consultations of 2442 children with family/general practitioners over the 6-week study periods during 1996-1997, with concurrent monitoring of particulate levels. The associations found between daily PM(10) levels and respiratory symptoms were frequently small and positive and sometimes varied between communities. The magnitude of these associations were in line with those from previous studies, even though daily particulate levels were low, and the children were drawn from the general population, rather than from the population with respiratory problems. The associations among asthma reliever use, consultations with general practitioners, and daily particulate levels were of a similar strength but estimated less precisely. The strength of association between all respiratory health measures and particulate levels was similar in communities near and away from opencast coal mining sites.

Consultations of children living near open-cast coal mines

Because of local concerns, general practitioner consultation rates in children living in communities close to and away from open-cast mines were compared. Information on consultations was collected on 2,442 children 1-11 years of age living in five socioeconomically matched pairs of open-cast and control communities in northern England. The data collection periods were 6 weeks each during 1996-1997 and the 52-week periods preceding these weeks. Consultations were categorized as respiratory, skin and eye conditions (possibly exacerbated by particulate matter), or other conditions. Over the 6-week periods, children in 4/5 pairs of open-cast and control communities had similar consultation rates for all conditions combined [2.7 vs. 2.4 per person-year; odds ratio (OR) = 1.1; 95% confidence interval (CI), 0.96-1.3). Consultations were higher in the open-cast communities for respiratory, skin, and eye conditions (2.1 vs. 1.5 per person-year; OR = 1.4; 95% CI, 1.2-1.7), and respiratory conditions alone (1.5 vs. 1.1 per person-year; OR = 1.5; 95% CI, 1.2-1.8). However, increases in consultation rates in open-cast communities were generally not seen over the portions of the 52-week periods when the open-cast sites were either active or inactive.

Prevalence of asthma and other respiratory symptoms in children living near and away from opencast coal mining sites

BACKGROUND

Public concern about respiratory conditions prompted the investigation of asthma and other respiratory diseases in children living near and away from opencast coal mining sites.

METHODS

We selected all 4860 children aged 1--11 years from five socioeconomically matched pairs of communities close to (OC) and away from (CC) active opencast sites. A postal questionnaire collected data on health and lifestyle. Outcomes were the cumulative and period prevalence (2 and 12 months) of wheeze, asthma, bronchitis and other respiratory symptoms.

RESULTS

The cumulative prevalence of wheeze varied from 30% to 40% across the ten communities, it was 36% in OC and 37% in CC. The cumulative prevalence of asthma was 22% in both OC and CC, varying between 12% and 24%. We found little evidence for associations between living near an opencast site and an increased prevalence of respiratory illnesses, or asthma severity. Some outcomes such as allergies, hayfever, or cough varied little across the study communities. Others, such as the use of asthma medication, the number of severe wheezing attacks in the past year or tonsillitis showed large variation. These similarities and variations were not explained by differences in lifestyle factors or differences in health services delivery and remain unexplained.

CONCLUSIONS

There was little evidence of an association between residential proximity to opencast mining sites and cumulative or period prevalence of respiratory illness, or asthma severity. Some variations in health outcomes between communities remained unexplained.

Is it feasible to construct a community profile of exposure to industrial air pollution?

OBJECTIVE

An epidemiological investigation to assess the validity of residential proximity to industry as a measure of community exposure.

METHODS

19 Housing estates in Teesside (population 1991: 77 330) in north east England were grouped into zones: A=near; B=intermediate; C=further from industry. With residential proximity of socioeconomically matched populations as a starting point a historical land use survey, historical air quality reports, air quality monitoring, dispersion modelling data, and questionnaire data, were examined.

RESULTS

The populations in zones A, B, and C were similar for socioeconomic indicators and smoking history. Areas currently closest to industry had also been closest for most of the 20th century. Historical reports highlighted the influence of industrial emissions to local air quality, but it was difficult to follow spatial pollution patterns over time. Whereas contemporary NO(x) and benzene concentrations showed no geographical variation, dispersion modelling of emissions (116 industrial stacks, traffic, and domestic sources) showed a gradient associated with industry. The presumed exposure gradient of areas by proximity to industry (A>B>C) was evident for all of zone A and most of zones B and C.

CONCLUSIONS

It was feasible to assemble a picture of community exposure by integration of measurements from different sources. Proximity of residence was a reasonable surrogate for complex community exposure.

Living near opencast coal mining sites and children's respiratory health

OBJECTIVES

To answer the question whether living near opencast coal mining sites affects acute and chronic respiratory health.

METHODS

All 4860 children aged 1-11 from five socioeconomically matched pairs of communities close to active opencast sites and control sites away from them were selected. Exposure was assessed by concentrations of particulate matter with aerodynamic diameter < 10 microns (PM10), residential proximity to active opencast sites, and particle composition. PM10 was monitored and sampled for 6 weeks in four pairs, and for 24 weeks in one pair. A postal questionnaire collected data on health and lifestyle. Daily health information was collected by a symptom diary (concurrently with PM10 monitoring) and general practitioner (GP) records were abstracted (concurrently with PM10 monitoring and 52 weeks before the study). Outcomes were the cumulative and period prevalence (2 and 12 months) of wheeze, asthma, bronchitis, and other respiratory symptoms, and the prevalence and incidence of daily symptoms and GP consultations.

RESULTS

Patterns of the daily variation of PM10 were similar in opencast and control communities, but PM10 was higher in opencast areas (mean ratio 1.14, 95% confidence interval (95% CI) 1.13 to 1.16, geometric mean 17.0 micrograms/m3 v 14.9 micrograms/m3). Opencast sites were a measurable contributor to PM10 in adjacent areas. Little evidence was found for associations between living near an opencast site and an increased prevalence of respiratory illnesses, asthma severity, or daily diary symptoms, but children in opencast communities 1-4 had significantly more respiratory consultations (1.5 v 1.1 per person-year) than children in control communities for the 6 week study periods. Associations between daily PM10 concentrations and acute health events were similar in opencast and control communities.

CONCLUSIONS

Children in opencast communities were exposed to a small but significant amount of additional PM10 to which the opencast sites were a measurable contributor. Past and present respiratory health of children was similar, but GP consultations for respiratory conditions were higher in opencast communities during the core study period.

Does living near a constellation of petrochemical, steel, and other industries impair health?

OBJECTIVES

To investigate concern that local industrial air pollution in Teesside, England, was causing poor health, several areas there were compared with parts of the City of Sunderland.

METHODS

Populations in similar social and economic circumstances but varying in their proximity to major industries were compared. Study populations lived in 27 housing estates in Teesside and Sunderland, north east England, with some data from subsets of estates. The estates were aggregated into zones (designated as A, B, and C in Teesside where A is closest to and C furthest from industry, and S in Sunderland). Zone S provided a reference area. The hypothesis was that a health gradient both within Teesside (A > B > C) and between Teesside and Sunderland (ABC > S) would indicate a possible health effect of local industrial air pollution. Data presented were: mortality (1981-91) from 27 housing estates; population self completion questionnaire survey data (1993, 9115 subjects) from 15 housing estates; and general practitioner (GP) consultation data (1989-94) from 2201 subjects in 12 Teesside estates.

RESULTS

The populations in the four zones were comparable for indicators including smoking habits, residential histories, and unemployment. All cause and cause specific mortalities were high compared with England and Wales. Mortality in all Teesside zones (ABC) combined was mostly higher than in zone S. In people aged 0-64, lung cancer and respiratory disease showed gradients with highest mortality in areas closest to industry (A > B > C and ABC > S). The association was clearest for lung cancer in women (0-64 years old, trend across zones ABC, p = 0.07, directly standardised rate ratio relative to zone S was 169 (95% confidence interval (95% CI) 116-122)). There were no important, consistent gradients in the hypothesised direction between zones in consultation rates in general practice, and self reported respiratory and nonrespiratory health including asthma.

CONCLUSIONS

There was no clear evidence that living close to industry was associated with morbidity, including asthma, or for most measures of mortality. For lung cancer in women the gradients indicated a health effect of local industrial air pollution. In the age group 0-64 observed gradients in lung cancer in men and mortality from respiratory disease in men and women were consistent with the study hypothesis, although not significant. The reasons for the different patterns at different ages, and between men and women, remain a puzzle.

alpha-1-Microglobulin: epidemiological indicator for tubular dysfunction induced by cadmium?

OBJECTIVES

To evaluate the suitability of alpha-1-microglobulin as a marker for cadmium induced renal dysfunction.

METHODS

alpha-1-Microglobulin was studied in a cross sectional survey in relation to the body burden of cadmium. Concentrations of alpha-1-microglobulin in 24 h urine of 831 people aged 2-87 years were analysed in association with urinary cadmium excretion, cadmium blood concentration, age, sex, occupational and smoking history, and estimated creatinine clearance. Participants came from a population residentially exposed to cadmium and from two control populations matched for socioeconomic status.

RESULTS

The excretion of alpha-1-microglobulin/24 h ranged from 0.1 mg to 176.3 mg and 44.4% of samples showed concentrations near the detection limit. Ordinal logistic regression analysis of people of all ages identified a high risk only for males compared with females (odds ratio (OR) 2.14; 95% confidence interval (95% CI) 1.56 to 2.94), age group, and duration of living on contaminated soil (OR 1.03/year; 95% CI 1.02 to 1.04), but not urinary cadmium excretion (OR 1.30; 95% CI 0.96 to 1.77) as significant predictors. For people < or = 50 years of age a weaker effect of sex (OR 1.76; 95% CI 1.13 to 2.73) and age group and an effect of similar magnitude for the duration of soil exposure (OR 1.03; 95% CI 1.01 to 1.04) were found. Also, the urinary cadmium excretion (OR 2.26; 95% CI 1.38 to 3.70) and occupational exposure (OR 1.71; 95% CI 1.03 to 2.83) were found to be significant in this younger age group. The estimated creatinine clearance had no significant impact on the alpha-1-microglobulin excretion.

CONCLUSION

alpha-1-Microglobulin is a suitable marker for early tubular changes only for people < or = 50 years. It may not be sufficiently specific for cadmium, and therefore not a suitable surrogate for cadmium exposure in epidemiological studies.

Lung cancer, proximity to industry, and poverty in northeast England

This study assesses whether deprived populations living close to industry experience greater mortality from lung cancer than populations with comparable socioeconomic characteristics living farther away. Mortality data, census data, a postal survey of living circumstances, historic and contemporary data on air quality and a historic land-use survey were used. Analysis was based on two conurbations in England, Teesside and Sunderland. Housing estates in Teesside were selected based on socioeconomic criteria and distinguished by proximity to steel and chemical industries; they were grouped into three zones: near (A), intermediate (B), and farther (C), with a single zone in Sunderland. We included 14,962 deaths in 27 estates. Standardized mortality ratios (SMR) for lung cancer [International Classification of Diseases #9 (ICD-9) 162] and cancers other than lung (ICD-9 140-239, excluding 162), and sex ratios were calculated. Mortality from lung cancer was well above national levels in all zones. For men, a weak gradient corresponding with proximity to industry at younger ages reversed at older ages. In women 0-64 years of age, stronger gradients in lung cancer mortality corresponded with proximity to industry across zones A, B, and C (SMR = 393, 251, 242, respectively). Overall rates in Teesside were higher than Sunderland rates for women aged 0-64 years (SMR = 287 vs. 185) and 65-74 years (SMR = 190 vs. 157). The association between raised lung cancer mortality and proximity to industry in women under 75 years of age could not be explained by smoking, occupation, socioeconomic factors, or artifact. Explanations for differences between men and women may include gender-specific occupational experiences and smoking patterns. Our judgment is that the observed gradient in women points to a role for industrial air pollution.