Risk of limb birth defects and mother's home proximity to cornfields

Background

Although previous studies have linked proximity to crops and birth defects, they lacked individual-level exposure data and none was based on using planted area instead of linear proximity to crops as the exposure metric. We studied birth defects in relation to the area of corn or soybeans within 500 m of the mother's residence.

Methods

We selected all singleton births from rural areas conceived during the 2000-2004 spring-summer months (n = 48,216). We determined whether the area with corn or soybeans around the home was associated with birth defects using multiple unconditional logistic regression.

Results

We found that limb birth defects (ICD-9-CM 754.5, 755) increased in relation to cornfields (Adjusted OR = 1.22; 95 % CI = 1.01, 1.47 per additional 10 ha planted with corn within 500 m). None of the birth defect types studied was associated with soybeans.

Conclusions

In the Midwest, a significant and expanding proportion of the population is now living in close proximity to cornfields. Our results suggest that additional studies should be conducted to identify which factor(s) associated with cornfields are behind the observed increase in limb birth defects.     

Heavy metal exposure in patients suffering from electromagnetic hypersensitivity

Background

Risks from electromagnetic devices are of considerable concern. Electrohypersensitive (EHS) persons attribute a variety of rather unspecific symptoms to the exposure to electromagnetic fields. The pathophysiology of EHS is unknown and therapy remains a challenge.

Objectives

Heavy metal load has been discussed as a potential factor in the symptomatology of EHS patients. The main objective of the study was to test the hypothesis of a link between EHS and heavy metal exposure.

Methods

We measured lead, mercury and cadmium concentrations in the blood of 132 patients (n = 42 males and n = 90 females) and 101 controls (n = 34 males and n = 67 females).

Results

Our results show that heavy metal load is of no concern in most cases of EHS but might play a role in exceptional cases.

Conclusions

The data do not support the general advice to heavy metal detoxification in EHS.     

The association between arsenic exposure from drinking water and cerebrovascular disease mortality in Taiwan

Background

Chronic arsenic exposure is associated with a variety of diseases, including cancer, peripheral vascular disease, and diabetes. However, its association with cerebrovascular diseases (CVD) has not yet been resolved. The aim of this study is to explore this association in Taiwan using nation-wide data.

Materials and methods

We analyzed mortality data in Taiwan from 1971 to 2005 and choose two geographic areas with populations suffering from chronic exposure to arsenic in drinking water for study, the blackfoot disease endemic area (BFDEA) in the southwest and Lan-Yang Basin (LYB) in the northeast parts of Taiwan. The Chia-Yi and Tainan Counties, which surround the BFDEA, and the nation of Taiwan as a whole were used as reference populations. Direct standardized mortality rates and gender-specific indirect standardized mortality ratios (SMRs) were calculated for the four populations.

Results

The direct standardized mortality rate for CVD in Taiwan decreased from 2.46/10³ person-year in 1971 to 0.63/10³ person-year in 2005, and women had significantly lower mortality than men (SMR = 0.80; p < 0.05). The CVD mortality rates of populations with chronic arsenic exposure were significantly higher than the reference populations (SMR ranging from 1.06 to 1.09 in men and 1.12 to 1.14 in women; p < 0.05). The BFDEA had higher CVD mortality rates than the LYB, with SMR = 1.05 (p < 0.05) in men and SMR = 1.04 (p = 0.05) in women.

Conclusion

In Taiwan, while CVD mortality decreased in both genders between 1971 and 2005, chronic arsenic exposure from drinking water was associated with increased risks of CVD.     

Exposure to toxic agents alters organic elemental composition in human fingernails

Background and objective:

The human fingernail plate is highly keratinized. The keratin structure is held together by disulfide bonds. The organic elements sulfur and nitrogen occur almost exclusively in amino acids of the nail plate. This study analyzed whether occupational exposure to harmful chemical agents alters the organic elemental composition in fingernails.

Subjects and methods:

Participants were 71 occupationally exposed workers (49 hairdressers, 22 painters) and 49 unexposed controls. Aspects of exposure were assessed by questionnaire. Nail clippings of index and little fingers were analyzed for sulfur (S), nitrogen (N), carbon (C), and hydrogen (H) contents, using an automatic elemental analyzer (Vario EL III, Elementar Analysensysteme, Hanau, Germany). C/N, N/S, and C/S ratios were calculated. Reliability of elemental measurements was tested in a subset.

Results:

Reliability analysis of elemental measurements showed a very good agreement. Both painters and hairdressers displayed in their fingernails significantly lower percentages of sulfur, but higher percentages of carbon than unexposed controls. A trend was observed in that sulfur content was lowest in those hairdressers who reported structural changes in their fingernails. As a consequence, the C/S and N/S ratios were significantly increased in both exposed groups.

Conclusion:

The occupational use of harmful substances leads to decreased sulfur levels in the exposed persons, probably due to diminution of sulfur-rich proteins in the nails, resulting from destruction of disulfide-bonds by alkaline and acid groups. Thus, the C/S ratio seems to be a useful indicator for the amount of damage of nail protein by harmful agents.     

The association between fine particulate air pollution and hospital emergency room visits for cardiovascular diseases in Beijing, China

Background

Because epidemiological studies have yielded different results, the association between exposure to fine particulate matter less than 2.5 μm in aerodynamic diameter (PM_2.5) and acute events of cardiovascular diseases (CVD) is unknown. Additionally, no research has been conducted to explore the association between PM_2.5 and hospital emergency room (ER) visits of cardiovascular diseases in Beijing, China.

Objective

To explore the association between PM_2.5 and the hospital ER visits in Beijing, China for CVD {(International Classification of Diseases, 10th vision (ICD-10): I00~I99)}.

Methods

We collected data for daily hospital ER visits for CVD from the Peking University Third Hospital, daily ambient PM_2.5 data from a fixed monitor site at Peking University, and data on the daily level of gaseous air pollutants {sulfur dioxide (SO₂) and nitrogen dioxide (NO₂)} from the Beijing Municipal Environmental Monitoring Center between June 1, 2004 and December 31, 2006. A time-stratified case-crossover design was used to evaluate associations between CVD health outcomes and ambient air pollutants.

Results

8377 hospital ER visits of CVD were collected in our study. After adjusting the temperature and the relative humidity, the associations for 10 μg/m³ increases in levels of PM_2.5, SO₂, or NO₂ and hospital ER visits for cardiovascular diseases were statistically significant with odds ratios (ORs) of 1.005{95% confidence interval (CI): 1.001-1.009}, 1.014(95% CI: 1.004-1.024), and 1.016(95% CI: 1.003-1.029), respectively.

Conclusion

These findings suggest that elevated levels of ambient air pollutants are associated with the increase in hospital ER visits for CVD in Beijing, China.     

Urinary 1-hydroxypyrene and PAH exposure in 4-year-old Spanish children

Aims:

Exposure to polycyclic aromatic hydrocarbons (PAH), among the main compounds present in polluted urban air, is of concern for children's health. Childhood exposure to PAH was assessed by urinary monitoring of 1-hydroxypyrene (1-OHP), a pyrene metabolite, investigating its association with exposure to air pollution and other factors related to PAH in air.

Methods:

A group of 174 4-year-old children were recruited and a questionnaire on their indoor and outdoor residential environment was completed by parents. At the same time, environmental measurements of traffic-related air pollution (NO₂) were carried out. A urine sample was collected from each child in order to analyze 1-OHP using HPLC with fluorescence detection, correcting for creatinine concentrations. Non-parametric tests and regression analyses were used to identify environmental factors that influence 1-OHP excretion.

Results:

Mean urinary 1-OHP concentration was 0.061 μmol/mol creatinine, ranging from 0.004 to 0.314 μmol/mol. Non-parametric tests and regression analysis showed positive and significant associations (P ≤ 0.05) between 1-OHP and predicted residential exposure to NO₂ (which was based on outdoor environmental measurements and geo-statistical analysis), self-reported residential vehicle traffic, passive smoking and cooking appliance. 1-OHP levels tended to be higher among children living in urban areas (0.062 μmol/mol vs. 0.058 μmol/mol for children living in rural areas) but differences were not significant (P = 0.20).

Conclusion:

In Southern Spain, concentrations of urinary 1-OHP were in the lower range of those generally reported for children living in non-polluted areas in Western Europe and the USA. Traffic-related air pollution, passive smoking and cooking appliance influenced urinary 1-OHP level in the children, which should be prevented due to the health consequences of the inadvertent exposure to PAH during development.     

Prenatal exposure to lead in Spain: cord blood levels and associated factors

Introduction and Objective

Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood).

Methods

A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2 μg/dL).

Results

A low percentage of cord blood samples with lead levels ≥ 2 μg/dL were found (5.9%). Geometric mean and maximum were 1.06 μg/dL and 19 μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2 μg/dL.

Conclusion

In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels.     

Maternal exposure to floricultural work during pregnancy, PON1 Q192R polymorphisms and the risk of low birth weight

Background

Although there is evidence from animal studies of impaired reproductive function by exposure to organophosphates (OP), the effects on birth weight have not been sufficiently evaluated in epidemiological studies. Paraoxonase (PON1) detoxifies organophosphates by cleavage of active oxons. Some PON1 gene polymorphisms could reduce the enzyme activity and increase susceptibility to OP toxicity.

Objective

To assess the association between maternal exposure to floriculture during pregnancy and the risk of low birth weight (< 2500 g) in their offspring, as well as to evaluate the interaction between this exposure and maternal genotype for PON1 Q192R polymorphisms.

Materials and methods

A cross sectional study was carried out in two Mexican states (States of Mexico and Morelos) with high frequencies of greenhouse activity. We interviewed and collected blood samples from 264 females (floriculturists or partners of floricultural workers) who became pregnant during the 10 years prior to the interview. The questionnaire measured socioeconomic characteristics, tobacco and alcohol consumption, diseases and occupational and reproductive history. We also applied a food frequency questionnaire. Information was obtained pertaining to 467 pregnancies. DNA was extracted from white cells, and PON1 genotype was determined by Restriction Fragment Length Polymorphism for Q192R polymorphisms. Results were analyzed with generalized estimating equations models.

Results

After adjusting for potential confounders, we detected a statistically significant interaction between maternal exposure to flower growing work during pregnancy and PON1 Q192R polymorphisms on risk of low birth weight. The risk of having a baby with LBW is nearly six times higher if a mother is a floriculture worker during pregnancy and has PON1 192RR genotype (OR 5.93, 95% CI 1.28, 27.5).

Conclusion

These results suggest that the interaction between maternal floriculture work during pregnancy and 192RR PON1 genotype increases the probability of having children with LBW.     

Exposure to polycyclic aromatic hydrocarbons and missed abortion in early pregnancy in a Chinese population

Background

Polycyclic aromatic hydrocarbons (PAHs) are formed during incomplete burning of fossil fuels, wood, and tobacco products. High PAH exposure has been associated with low birth weight, intrauterine growth restriction, and preterm birth, but little is known about its impact on adverse outcomes in early pregnancy such as in-utero fetal death.

Objectives

To examine associations between exposure to PAHs and missed abortion in which the embryo has died but a miscarriage has not yet occurred during early pregnancy in a Chinese population in Tianjin.

Methods

A case-control study was conducted from April to November, 2007 in Tianjin, China. Cases experienced a missed abortion while controls underwent elective abortions before 14 weeks of pregnancy. Eighty-one cases were recruited from four hospitals, with the same number of controls matched on hospital, maternal age (± 8 years), gravidity (1 or >1), and gestational age (± 30 days). Two maternal measures of PAH exposures were obtained based on benzo[a]pyrene (BaP) DNA adducts in 1) aborted tissues and 2) maternal blood (for a subset of subjects). In addition, proxy measures for PAH exposures from different sources were derived from maternal interviews.

Results

In conditional logistic regression analyses, we estimated more than 4-fold increase in risk of having experienced a missed abortion in women with above the median levels of blood BaP-DNA adducts (adjusted OR = 4.27; 95% CI, 1.41-12.99); but no increase with adduct levels in aborted tissues (adjusted OR = 0.76; 95% CI, 0.37-1.54). BaP-DNA adduct levels in maternal blood and aborted tissues were poorly correlated (r = − 0.12; n = 102). Missed abortion risk also was higher among women reporting traffic congestion near the residence, commuting by walking, and performing regular cooking activities during pregnancy.

Conclusion

High levels of maternal PAH exposures may contribute to an increased risk of experiencing a missed abortion during early pregnancy.     

Lead in saliva from lead-exposed and unexposed children

Introduction

Whole blood is used for diagnosis of lead exposure. A non-invasive method to obtain samples for the biomonitoring of lead contamination has become a necessity. This study 1) compares the lead content in whole saliva samples (Pb-saliva) of children from a city with no reported lead contamination (Ribeirão Preto, São Paulo State, Brazil) and children of a region notoriously contaminated with lead (Bauru, São Paulo State, Brazil), and 2) correlates Pb-saliva with the lead content in the enamel microbiopsy samples (Pb-enamel) in the case of these two populations.

Methods

From a population of our previous study that had included 247 children (4- to 6-year-old) from Ribeirão Preto, and 26 children from Bauru, Pb-saliva was analyzed in 125 children from Ribeirão Preto and 19 children from Bauru by inductively coupled plasma mass spectrometry (ICPMS). To correlate Pb-saliva with Pb-enamel, we used Pb-enamel data obtained in our previous study. The Mann-Whitney test was employed to compare the Pb-saliva data of the two cities. Pb-saliva and Pb-enamel values were then Log₁₀ transformed to normalize data, and Pb-saliva and Pb-enamel were correlated using Pearson's correlation coefficient.

Results

Median Pb-saliva from the Ribeirão Preto population (1.64 μg/L) and the Bauru population (5.85 μg/L) were statistically different (p < 0.0001). Pearson's correlation coefficient for Log₁₀ Pb-saliva versus Log₁₀ Pb-enamel was 0.15 (p = 0.08) for Ribeirão Preto and 0.38 (p = 0.11) for Bauru.

Conclusions

A clear relationship between Pb-saliva and environmental contamination by lead is shown. Further studies on Pb-saliva should be undertaken to elucidate the usefulness of saliva as a biomarker of lead exposure, particularly in children.     

Community response to environmental noise and the impact on cardiovascular risk score

Objective

The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.

Methods

The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, L_eq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, L_eq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).

Results

Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).

Conclusions

These findings highlight the association between road traffic noise and cardiovascular risk.     

Sensitization to profilin in the Central region of Portugal

Background

Profilin is a panallergen found in pollens and fruits. Sensitization to this protein may explain some sensitization to multiple pollen species. We aimed to evaluate sensitization to profilin in patients suffering from respiratory allergy sensitized to pollens, in the Central region of Portugal.

Methods

Patients were evaluated for asthma symptoms, rhinitis, conjunctivitis and food allergy. Skin prick tests (SPT) to aeroallergens including 12 different pollens and profilin (nPho d 2) were performed. The patients were divided into two study groups according to the region of residence: A — inland region and B — coastal region.

Results

A total of 370 patients were evaluated (277-group A; 93-group B). 65.9% showed positive skin prick tests and 76.2% were positive to pollens (87.1%-group A; 42.85%-group B; p < 0.0001). All the patients sensitized to pollens had rhinitis (p = 0.001). Sensitization to profilin was associated with pollen sensitization (p = 0.014). 43 patients were sensitized to profilin (40-group A; 3-group B; p = 0.006). 21.0% of patients sensitized to pollens, were also sensitized to profilin. 39 patients were sensitized to at least two pollens (p < 0.0001). Four profilin and pollen sensitized patients had oral allergy syndrome complaints to melon. This syndrome was related with profilin sensitization (p = 0.001).

Conclusions

It is advisable to perform SPT to profilin, particularly in the Inland region, for a better differential diagnosis between cross-reactivity and true sensitization to pollens. The results together with the medical history may support the choice for a specific immunotherapy option.     

Anthropogenic contributions to mercury levels in present-day Arctic animals—A review

Background

Because of concern about the recently increasing levels of biological Hg in some areas of the Arctic, we examined the literature concerning the long-term changes of Hg in humans and selected Arctic marine mammals and birds of prey since pre-industrial times (i.e. before 1800 A.D.), to determine the anthropogenic contribution to present-day Hg concentrations and the historical timing of any changes.

Methods

Mercury data from published articles were extracted on historical and pre-industrial concentrations as percentages of the recent maximum, as well as the man-made contribution was calculated and depicted in a uniform manner to provide an overview of the development over time.

Results and discussion

Trends of [Hg] in hard tissues such as teeth, hair and feathers consistently showed that there had been an order-of-magnitude increase of [Hg] in Arctic marine foodweb-based animals that began in the mid- to late-19th Century and accelerated in the 20th Century. The median man-made contribution to present-day Hg concentrations was 92.4% ranging from 74.2 to 94.4%. Confidence in our data was increased by accompanying data in some studies on stable isotopes (δ¹³C, δ¹⁵N), which allowed us to normalize where necessary for changes in animal trophic position and feeding location over time, and by careful attention to the possibility of sample chemical diagenesis (Hg contamination or loss) which can alter the Hg content of ancient hard tissues.

Conclusions

Wildlife hard tissue matrices provide consistent information with respect to the steep onset of Hg exposure of Arctic wildlife beginning in the latter half of the 19th Century. Today the man-made contribution was found to be above 92%. Stable isotope analyses provide important information to normalize for possible changes in diet over time, and are highly relevant to include when interpreting temporal trends, baseline concentrations as well as man-made anthropogenic contribution of Hg.     

Prenatal exposure to organochlorine pesticides and TSH status in newborns from Southern Spain

Objective

To investigate the association between prenatal exposure to organochlorine pesticides (OCPs) and thyroid-stimulating hormone (TSH) levels in male newborns.

Methods

Exposure to 17 OCPs was analyzed in 220 placentas from a male birth cohort in Southern Spain, and TSH was measured in the umbilical cord blood. OCP concentrations were quantified by gas chromatography and mass spectrometry. Multivariate regression analysis was conducted to examine the association between pesticide exposure and neonatal TSH levels, adjusting for confounders.

Results

Newborn boys with higher exposure to endrin in placenta had higher odds of TSH cord blood levels ≥ 5 mU/L (80th percentile) (OR = 2.05; 95% CI = 1.01, 4.18; p = 0.05), whereas higher prenatal exposure to endosulfan-sulfate was associated with lower odds of TSH ≥ 5 mU/L (OR = 0.36; 95% CI = 0.17, 0.77; p = 0.008). A marginally significant negative association was found between TSH and hexachlorobenzene levels (β = − 0.15; 95% CI = − 0.31, 0.02; p = 0.09), and exposure to p,p′-DDE showed a marginally-significant higher odds of TSH ≥ 5 mU/L (OR = 1.32; 95% CI = 0.95, 1.83; p = 0.09). No association was found between TSH and the remaining pesticides.

Conclusions

Early exposure to certain environmental chemicals with endocrine-disruption activity may interfere with neonatal thyroid hormone status; however, the pattern of interference is not yet clearly elucidated.     

Mapping of background air pollution at a fine spatial scale across the European Union

Background

There is a need to understand much more about the geographic variation of air pollutants. This requires the ability to extrapolate from monitoring stations to unsampled locations. The aim was to assess methods to develop accurate and high resolution maps of background air pollution across the EU.

Methods

We compared the validity of ordinary kriging, universal kriging and regression mapping in developing EU-wide maps of air pollution on a 1 × 1 km resolution. Predictions were made for the year 2001 for nitrogen dioxide (NO₂), fine particles < 10 µm (PM₁₀), ozone (O₃), sulphur dioxide (SO₂) and carbon monoxide (CO) using routine monitoring data in Airbase. Predictor variables from EU-wide databases were land use, road traffic, population density, meteorology, altitude, topography and distance to sea. Models were developed for the global, rural and urban scale separately. The best method to model concentrations was selected on the basis of predefined performance measures (R², Root Mean Square Error (RMSE)).

Results

For NO₂, PM₁₀ and O₃ universal kriging performed better than regression mapping and ordinary kriging. Validation of the final universal kriging estimates with results from all validation sites gave R²-values and RMSE-values of 0.61 and 6.73 µg/m³ for NO₂; 0.45 and 5.19 µg/m³ for PM₁₀; and 0.70 and 7.69 µg/m³ for O₃. For SO₂ and CO none of the three methods was able to provide a satisfactory prediction.

Conclusion

Reasonable prediction models were developed for NO₂, PM₁₀ and O₃ on an EU-wide scale. Our study illustrates that it is possible to develop detailed maps of background air pollution using EU-wide databases.     

Short-term effect of fine particulate matter (PM2.5) on daily mortality due to diseases of the circulatory system in Madrid (Spain)

Introduction

Owing to their small size, fine particles, i.e., those having a diameter ≤ 2.5 μm (PM_2.5), have a high alveolar penetration capacity, thereby triggering a local inflammatory process with circulatory repercussion. Despite being linked to respiratory and cardiovascular morbidities, there is limited evidence of an association between this type of particulate matter and short-term increases in mortality.

Objective

The aim of this study was to analyse and quantify the short-term impact of PM_2.5 on daily mortality due to diseases of the circulatory system, registered in Madrid from 1 January 2003 to 31 December 2005.

Methods

An ecological longitudinal time-series study was conducted, with risks being quantified by means of Poisson regression models. As a dependent variable, we took daily mortality registered in Madrid from 1 January 2003 to 31 December 2005, attributed to all diseases of the circulatory system as classified under heads I00-I99 of the International Classification of Diseases-10th revision (ICD-10) and broken down as follows: I21, acute myocardial infarction (AMI); I20, I22-I25, other ischemic heart diseases; and I60-I69, cerebrovascular diseases. The independent variable was daily mean PM_2.5 concentration. The other variables controlled for were: chemical pollution (PM₁₀, O₃, SO₂, NO₂ and NO_x); acoustic and biotic pollution; influenza; minimum and maximum temperatures; seasonalities; trend; and autocorrelation of the series.

Results

A linear relationship was observed between PM_2.5 levels and mortality due to diseases of the circulatory system. For every increase of 10 μg/m³ in daily mean PM_2.5 concentration, the relative risks (RR) were as follows: for overall circulatory mortality, associations were established at lags 2 and 6, with RR of 1.022 (1.005-1.039) and 1.025 (1.007-1.043) respectively; and for AMI mortality, there was an association at lag 6, with an RR of 1.066 (1.032-1.100). The corresponding attributable risks percent (AR%) were 2.16%, 2.47% and 6.21% respectively. No statistically significant association was found with other ischemic heart diseases or with cerebrovascular diseases.

Conclusion

PM_2.5 concentrations are an important risk factor for daily circulatory-cause mortality in Madrid. From a public health point of view, the planning and implementation of specific measures targeted at reducing these levels constitute a pressing need.     

Mortality due to lung, laryngeal and bladder cancer in towns lying in the vicinity of combustion installations

Background

Installations that burn fossil fuels to generate power may represent a health problem due to the toxic substances which they release into the environment.

Objectives

To investigate whether there might be excess mortality due to tumors of lung, larynx and bladder in the population residing near Spanish combustion installations included in the European Pollutant Emission Register.

Methods

Ecologic study designed to model sex-specific standardized mortality ratios for the above three tumors in Spanish towns, over the period 1994-2003. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using mixed Poisson regression models, we analyzed: risk of dying from cancer in a 5-kilometer zone around installations that commenced operations before 1990; effect of type of fuel used; and risk gradient within a 50-kilometer radius of such installations.

Results

Excess mortality (relative risk, 95% confidence interval) was detected in the vicinity of pre-1990 installations for lung cancer (1.066, 1.041-1.091 in the overall population; 1.084, 1.057-1.111 in men), and laryngeal cancer among men (1.067, 0.992-1.148). Lung cancer displayed excess mortality for all types of fuel used, whereas in laryngeal and bladder cancer, the excess was associated with coal-fired industries. There was a risk gradient effect in the proximity of a number of installations.

Conclusions

Our results could support the hypothesis of an association between risk of lung, laryngeal and bladder cancer mortality and proximity to Spanish combustion installations.     

High temperature effects on out-patient visits and hospital admissions in Chiang Mai, Thailand

Objectives

This study investigated the short-term effects of temperature on out-patient visits and hospital admissions in Chiang Mai, Thailand. While mortality outcomes in the literature have been reported, there is less evidence of morbidity effects with very few studies conducted in developing countries with subtropical or tropical climate.

Methods

Time-series regression analysis was employed using generalized negative binomial regression to model the short-term relationships between temperature and morbidity after controlling for seasonal patterns and other potential confounders. Lag effects up to 13 days and effect modification by age (0-14 years, 15-64 years, ≥ 65 years) were examined.

Results

Temperature effects with wide confidence intervals were found, with an increase in diabetic visits of 26.3% (95% CI: 7.1%-49.0%), and circulatory visits of 19.2% (95% CI: 7.0%-32.8%) per 1 °C increase in temperature above an identified threshold of 29 °C. Additionally, there was a rise of both visits (3.7% increase, 95% CI: 1.5%-5.9%) and admissions (5.8% increase, 95% CI: 2.3%-9.3%) due to intestinal infectious disease in association with each 1 °C increase across the whole temperature range. The effects of temperature were stronger in the elderly though not statistically significant.

Conclusions

Daily morbidity in Chiang Mai was positively associated with temperature with a lag effect of up to 2 weeks, which was longer than lag effects previously reported. Public health preparedness and interventions should be considered to minimise possible increased hospital visits and admissions during hot weather.