Estimated risk for altered fetal growth resulting from exposure to fine particles during pregnancy: an epidemiologic prospective cohort study in Poland.
The purpose of this study was to estimate exposure of pregnant women in Poland to fine particulate matter particulate matter
n. Abbr. PM
Material suspended in the air in the form of minute solid particles or liquid droplets, especially when considered as an atmospheric pollutant.
Noun 1. [[less than or equal to] 2.5 [micro]m in diameter (P[M.sub.2.5])] and to assess its effect on the birth outcomes. The cohort consisted of 362 pregnant women who gave birth between 34 and 43 weeks of gestation. The enrollment included only nonsmoking non·smok·ing
1. Not engaging in the smoking of tobacco: nonsmoking passengers.
2. Designated or reserved for nonsmokers: the nonsmoking section of a restaurant. women with singleton pregnancies, 18-35 years of age, who were free from chronic diseases such as diabetes and hypertension. P[M.sub.2.5] was measured by personal air monitoring over 48 hr during the second trimester Noun 1. second trimester - time period extending from the 13th to the 27th week of gestation
trimester - a period of three months; especially one of the three three-month periods into which human pregnancy is divided of pregnancy. All assessed birth effects were adjusted in multiple linear regression Linear regression
A statistical technique for fitting a straight line to a set of data points. models for potential confounding confounding
when the effects of two, or more, processes on results cannot be separated, the results are said to be confounded, a cause of bias in disease studies.
confounding factor factors such as the size of mother (maternal height, prepregnancy weight), parity, sex of child, gestational age ges·ta·tion·al age
See estimated gestational age.
The estimated age of a fetus expressed in weeks, calculated from the first day of the last normal menstrual period. , season of birth, and self-reported environmental tobacco smoke environmental tobacco smoke (ETS/passive smoke),
n the gaseous by-product of burning tobacco products, including but not limited to commercially manufactured cigarettes and cigars; contains toxic elements harmful to the health of adults and children (ETS ETS Educational Testing Service (nonprofit private educational testing and measurement organization)
ETS Emergency Telecommunications Service
ETS Electronic Trading System
ETS Engineering (&) Technical Services ). The regression model explained 35% of the variability in birth weight ([beta] = -200.8, p = 0.03), and both regression coefficients for P[M.sub.2.5] and birth length ([beta] = -1.44, p = 0.01) and head circumference (HC; [beta] = -0.73, p = 0.02) were significant as well. In all regression models, the effect of ETS was insignificant. Predicted reduction in birth weight at an increase of exposure from 10 to 50 [micro]g/[m.sup.3] was 140.3 g. The corresponding predicted reduction of birth length would be 1.0 cm, and of HC, 0.5 cm. The study provides new and convincing epidemiologic evidence that high personal exposure to fine particles Fine particles are an air pollutant mainly produced by cars running on diesel. Other sources are the combustion of fossil fuels in power plants and various industrial processes. is associated with adverse effects on the developing fetus. These results indicate the need to reduce ambient fine particulate concentrations. However, further research should establish possible biologic mechanisms explaining the observed relationship. Key words: air pollutants, cohort study A cohort study is a form of longitudinal study used in medicine and social science. It is one type of study design.
In medicine, it is usually undertaken to obtain evidence to try to refute the existence of a suspected association between cause and disease; failure to refute , fetal growth, pregnancy, prenatal exposure. Environ Health Perspect 112:1398-1402 (2004). doi:10.1289/ehp.7065 available via http://dx.doi.org/[Online 21 June 2004]
A large body of evidence demonstrates that, in addition to parental smoking (Bosley et al. 1981; Jedrychowski et al. 1977; Kallen 1997a, 1997b; Lowe 1959; Martinez et al. 1994; Miller et al. 1976; Savitz et al. 1991; Shaw et al. 1996; Simpson 1957; Underwood et al. 1967; Wasserman et al. 1996; Wyszynski et al. 1997) and environmental tobacco smoke (ETS) [Jedrychowski and Flak 1996; Mainous and Hueston 1994; Martin and Bracken 1986; National Research Council 1986; Ogawa et al. 1991; Perera et al. 2004; Rubin et al. 1986; U.S. Environmental Protection Agency Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise pollution, and radiation and to ensure the safe handling and (EPA EPA eicosapentaenoic acid.
n.pr See acid, eicosapentaenoic.
n. ) 1992; Windham et al. 1999), outdoor and indoor air pollutants may increase the risk of adverse birth outcomes, including low birth weight (LBW LBW Low birth weight, see there ), premature births, and intrauterine growth retardation Intrauterine Growth Retardation Definition
Intrauterine growth retardation (IUGR) occurs when the unborn baby is at or below the 10th weight percentile for his or her age (in weeks). (IUGR IUGR intrauterine growth retardation (or restriction).
intrauterine growth retardation
IUGR Intrauterine growth retardation, see there ) (Antipenko and Kogut 1993; Axelsson and Molin 1988; Bhopal et al. 1994, 1998; Bobak 2000; Bobak and Leon 1999; Dejmek et al. 1999, 2000; Kavlock et al. 1979; Landgren 1996; Lin et al. 2001; Longo 1997; Loomis et al. 1999; Norska-Borowka and Bursa Bursa, city, Turkey
Bursa (brsä`), city (1990 pop. 838,323), capital of Bursa prov., NW Turkey. 1993; Pereira et al. 1998; Perera et al. 1998, 2003; Ritz and Yu 1999; Ritz et al. 2000; Singh 1988; Smrcka and Leznarova 1998; Sram 1999; Tabacova and Balabaeva 1993; Wang et al. 1997; Woodruff et al. 1997; Xu et al. 1995). Despite the large number of studies dealing with air pollutants and birth outcomes, the evidence for a causal association remains still weak. Other studies comparing areas with wide ranges of exposure are needed to show the evidence for small effects.
It is assumed that areas in and around the home are important sources of chemical exposures for pregnant women, fetuses, and newborns. Toxic chemicals particularly may be present in proximity to industrial complexes and hazardous waste Hazardous waste
Any solid, liquid, or gaseous waste materials that, if improperly managed or disposed of, may pose substantial hazards to human health and the environment. Every industrial country in the world has had problems with managing hazardous wastes. sites, as well as deriving from local combustion sources such as cars, trucks, and bus routes. The home can also be subject to contamination by particulate matter (PM) and compounds such as nitrogen dioxide nitrogen dioxide
A poisonous brown gas, NO2, often found in smog and automobile exhaust fumes and synthesized for use as a nitrating agent, a catalyst, and an oxidizing agent.
Noun 1. , sulfur dioxide sulfur dioxide, chemical compound, SO2, a colorless gas with a pungent, suffocating odor. It is readily soluble in cold water, sparingly soluble in hot water, and soluble in alcohol, acetic acid, and sulfuric acid. , carbon monoxide carbon monoxide, chemical compound, CO, a colorless, odorless, tasteless, extremely poisonous gas that is less dense than air under ordinary conditions. It is very slightly soluble in water and burns in air with a characteristic blue flame, producing carbon dioxide; , and polycyclic aromatic hydrocarbons (PAHs).
Reproductive epidemiology provides evidence that fetuses and infants are likely to be significantly more sensitive to a variety of environmental toxicants than are adults. They are more sensitive because of differential exposure, physiologic immaturity, and a longer lifetime over which disease initiated in the early life can develop. Newborns and young children are especially vulnerable to the toxic effects of ETS, PAHs, PM, nitrosamines nitrosamines
highly hepatotoxic compounds formed in the rumen by the combination of amines and nitrite. They do not appear to occur naturally in large quantities. Nitrosamine poisoning has also been caused by feeding nitrite-treated fishmeal and Solanum incanum. , pesticides, polychlorinated biphenyls polychlorinated biphenyls, (pol´ēklôr´nā´tid bīfē´n , metals, and radiation (Perera et al. 2002).
The major difficulty in studying birth outcomes associated with air pollution lies in assessing exposure. Previous studies have attempted to quantify the concentration of outdoor air pollutants in the residence area such as total suspended particulates (TSP), particulate matter [less than or equal to] 10 [micro]m in diameter (P[M.sub.10]), S[O.sub.2], or CO and assign exposure values to the study subjects or use the area-based exposures to approximate individual exposures. Most prior studies, especially ecologic ones, did not consider important confounding factors such as maternal height and prepregnancy weight, smoking status, or occupational exposure.
The purpose of the present study was to estimate the exposure of pregnant women in Poland to potentially hazardous fine PM [[less than or equal to] 2.5 [micro]m in diameter (P[M.sub.2.5])] and to assess its effects on the birth outcomes [weight, length, and head circumference (HC) at birth]. To avoid potential methodologic limitations of previous studies regarding the assessment of exposure, we included assessment of personal individual exposure to fine particulate pollutants from all potential sources indoors and outdoors. In the analysis of the association between air pollutants and birth outcomes, we also considered important confounders such as maternal anthropometric an·thro·pom·e·try
The study of human body measurement for use in anthropological classification and comparison.
an characteristics, parity, sex of child, gestational age, and birth season.
Materials and Methods
The design of this cohort prospective study and the detailed selection of the population have been described previously (Jedrychowski et al. 2003). Briefly, this study is part of an ongoing comparative longitudinal investigation of the health impact of prenatal exposure to outdoor/indoor air pollution on infants and children being conducted in New York City New York City: see New York, city.
New York City
City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S. and Krakow. The ethics committee ethics committee A multidisciplinary hospital body composed of a broad spectrum of personnel–eg, physicians, nurses, social workers, priests, and others, which addresses the moral and ethical issues within the hospital. See DNR, Institutional review board. of the Jagiellonian University
The Jagiellonian University (Polish: Uniwersytet Jagielloński, often shortened to UJ approved the study.
We analyzed data from 362 women who gave birth between 34 and 42 weeks of gestation from January 2001 through March 2003. Women attending ambulatory prenatal clinics in the first and second trimesters of pregnancy were eligible for the study. The enrollment included only nonsmoking women with singleton pregnancies who were 18-35 years of age and were free from chronic diseases such as diabetes and hypertension. Recruited women were interviewed and given a description of the study and requirements for participation in the project. Each subject was given a detailed questionnaire at entry to the study and in the third trimester Noun 1. third trimester - time period extending from the 28th week of gestation until delivery
trimester - a period of three months; especially one of the three three-month periods into which human pregnancy is divided to solicit information on demographic data, house characteristics, date of the last menstrual period last menstrual period Gynecology The most recent time that a ♀ notes menstruation, a datum recorded in a chart during a routine gynecologic visit. See Menstruation. (LMP LMP left mentoposterior (position of fetus); last menstrual period.
last menstrual period
LMP Last menstrual period, see there ), medical and reproductive history reproductive history Obstetrics A set of 4 numbers that may be used to define a woman's obstetric Hx–eg, 4-3-2-1, would mean 4 term infants delivered, 3 preterm infants, 2 abortions, 1 child currently living , occupational hazards, alcohol consumption, and smoking practices of others present in the home. After participating women had given birth, maternal and child hospital records were reviewed to obtain data on complications of delivery. Weight, length, and HC at birth and Apgar score Ap·gar score
A system of evaluating a newborn's physical condition by assigning a value (0, 1, or 2) to each of five criteria: heart rate, respiratory effort, muscle tone, response to stimuli, and skin color. at 1 and 5 min were recorded for all infants. Gestational age at birth was defined as the interval between the last day of the mother's LMP and the date of birth.
Dosimetry dosimetry /do·sim·e·try/ (do-sim´e-tre) scientific determination of amount, rate, and distribution of radiation emitted from a source of ionizing radiation, in biological d. of prenatal personal exposure to fine particles. During the second trimester, a member of the air monitoring staff instructed the women in the use of the personal monitor, which is lightweight and quiet and is worn in a backpack. The women were asked to wear the monitor during daytime hours for 2 consecutive days and to place the monitor near the bed at night. During the morning of the second day, the air monitoring staff person and interviewer visited the women's homes to change the battery pack and administer the full questionnaire. They also checked to see that the monitor had been running continuously and that no technical or operating failures had occurred. A staff member returned to the women's homes on the morning of the third day to pick up the equipment.
A personal environmental monitoring sampler (PEMS PEMS Predictive Emissions Monitoring System
PEMS Portable Emissions Measurement System
PEMS Pharmacy Education Management System
PEMS Paris Evangelical Missionary Society
PEMS Power and Energy Management Solutions
PEMS Pre-and Early Modern Studies ) was used to measure particle mass. The PEMS is designed to achieve the particle target size of [less than or equal to] 2.5 [micro]m at a flow rate of 4.0 L/min with an array of 10 impactor nozzles. Flow rates were calibrated cal·i·brate
tr.v. cal·i·brat·ed, cal·i·brat·ing, cal·i·brates
1. To check, adjust, or determine by comparison with a standard (the graduations of a quantitative measuring instrument): (with filters in place) before the monitoring and were checked again with a change of the battery pack on the second day and at the conclusion of the monitoring. Pumps operated continuously at 2 L/min over the 48-hr period. To modify the sampler to achieve the 2.5-[micro]m size cutoff at 2 L/min, five of the nozzles were blocked. Particles were collected on Teflon membrane filter (37 mm Teflo; SKC SKC Salish Kootenai College (Pablo, MT)
SKC Sky Clear (Meteorology)
SKC St Kevin's College (Melbourne, Victoria-Australia)
SKC Chief Storekeeper , Inc., Eighty Four, PA, USA). The combination of low pressure drop (permitting use of a low-power sampling pump), low hygroscopicity hygroscopicity
the quality of being hygroscopic. (minimizing bound water interference in mass measurements), and low trace element background (improving analytical sensitivity) of these filters makes them highly appropriate for personal particle sampling. Dust air samples were analyzed by J.D.S. and his staff.
Statistical methods. The main birth outcomes were birth weight, length, and HC at birth, and association with exposure was examined by univariate and multivariate models. We constructed several models where exposure to P[M.sub.2.5] was treated as continuous and dichotomous di·chot·o·mous
1. Divided or dividing into two parts or classifications.
2. Characterized by dichotomy.
di·chot variables. First, crude effects were estimated, and subsequently they were adjusted to confounders. All maternal factors included in multivariate analyses were related to birth outcomes in bivariate bi·var·i·ate
Mathematics Having two variables: bivariate binomial distribution.
Adj. 1. analysis. In the final statistical analysis, we assessed the effect of P[M.sub.2.5] and ETS exposure on the birth outcomes by multiple linear regression, controlling for potential confounders (parity, height of mother, prepregnancy weight, sex of infant, gestational age, and season of birth). We tested seasons of year for confounding because of their association with exposure and their potential association with fetal growth. Season of birth was introduced in the regression models as a dummy variable This article is not about "dummy variables" as that term is usually understood in mathematics. See free variables and bound variables.
In regression analysis, a dummy variable , with summer defined as the reference level. Because the distribution of the air pollutants in question was skewed skewed
curve of a usually unimodal distribution with one tail drawn out more than the other and the median will lie above or below the mean.
skewed Epidemiology adjective Referring to an asymmetrical distribution of a population or of data , the P[M.sub.2.5] values were log transformed before entry into the regression models. Because the outliers of exposure to P[M.sub.2.5] did not change the regression estimates, they were not removed from the analysis. The ETS variable was categorized as follows: 1, no exposure; 2, exposed to [less than or equal to] 10 cigarettes smoked daily at home; 3, exposed to 11-20 cigarettes smoked daily at home; 4, exposed to > 20 cigarettes smoked daily at home. In all statistical analyses, the significance level was set at p < 0.05.
For testing the functional relationship between P[M.sub.2.5] and birth outcomes, we used generalized additive models in S-Plus (Mathsoft Inc., Seattle, WA, USA; Mathsoft 1999), including gestational age, sex of child, parity, height and prepregnancy weight of mother, and the delivery season. The analysis showed that the relationship between P[M.sub.2.5] and birth length did not differ from the linear relationship established by the linear multivariate regression model. The reduction of residual sum of squares In statistics, the residual sum of squares (RSS) is the sum of squares of residuals,
In a standard regression model , where a and b from 1978.73 for linear fit to 1955.09 was not significant (10 = 0.237). The corresponding estimates for birth weight and HC were similar.
Analysis of personal air samples from the 362 pregnant women enrolled in our study showed that P[M.sub.2.5] exposures averaged 43 [micro]g/[m.sup.3], with a range of 10.3-147.3 [micro]g/[m.sup.3]. The mean weight, length, HC at birth, and gestational age for infants under study were 3439.8 g, 54.6 cm, 33.9 cm, and 39.5 weeks, respectively. The newborns of mothers with higher exposures to fine particles in the period of monitoring (above the median of 36.3 [micro]g/[m.sup.3]) showed shorter length at birth by 0.9 cm. The corresponding reductions in HC and birth weight were 0.3 cm and 128.3 g, respectively (Table 1).
In the subsequent statistical analysis of the data, we used multiple linear multivariate regression models to examine the relationship between birth outcomes and the effect of fine particles and ETS. For each birth outcome, we constructed a separate model where dependent variables included gestational age, sex of child, season of birth, and variables on quality of air (ETS and level of P[M.sub.2.5]), as well as the anthropometry anthropometry (ănthrəpŏm`ətrē), technique of measuring the human body in terms of dimensions, proportions, and ratios such as those provided by the cephalic index. of the mother. Both variables of air quality correlated significantly (p = 0.01) with each other (r = 0.35), and the level of personal exposure to P[M.sub.2.5] depended on the number of cigarettes smoked daily at home (Figure 1).
[FIGURE 1 OMITTED]
Tables 2-4 present the standardized regression coefficient of P[M.sub.2.5] on the birth outcomes after accounting for all dependent variables. The regression model explained 33.4% of the variability in birth weight ([beta] = -200.8, p = 0.03), and both regression coefficients for P[M.sub.2.5] and birth length ([beta] = -1.44, p = 0.01) and HC ([beta] = -0.73, 0.02) were significant as well. In all regression models the effect of ETS was insignificant. Predicted reduction in birth weight at an increase of exposure from 10 to 50 [micro]g/[m.sup.3] was 140.3 g. The corresponding predicted reduction of birth length would be 1.0 cm, and of HC, 0.5 cm.
Finally, we explored the hypothesis that P[M.sub.2.5] had an adverse effect on gestational age. We did not find in the linear multivariate regression model that P[M.sub.2.5] or ETS shortened the duration of pregnancy.
Until now, there have been no studies of effects of personal exposure to fine particles on reproductive health Within the framework of WHO's definition of health as a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity, reproductive health, or sexual health/hygiene and birth outcomes. Our study draws attention to the fact that not only lower birth weight but also reduction in length and HC at birth might be caused by prenatal exposure to pollutants during pregnancy.
Analysis of personal air samples from the pregnant women enrolled in the Krakow study showed that total personal P[M.sub.2.5] exposures averaged 43.1 [micro]g/[m.sup.3] with a range of 10.3-147.3 [micro]g/m. None of the women under study in Krakow reported heavy exposure to dusty environments in the working hours. The P[M.sub.2.5] level in the Krakow study was very high and had a wide range of exposure, compared with data from the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. , where the range of annual mean for P[M.sub.2.5] measured in various sites is 1.2-14.2 [micro]g/[m.sup.3] (U.S. EPA 2003). However, the P[M.sub.2.5] exposure observed in Krakow would be comparable with that observed in the Czech Republic Czech Republic, Czech Česká Republika (2005 est. pop. 10,241,000), republic, 29,677 sq mi (78,864 sq km), central Europe. It is bordered by Slovakia on the east, Austria on the south, Germany on the west, and Poland on the north. , where the daily mean is 35.6 [micro]g/[m.sup.3] (Dejmek et al. 1999).
The analysis of birth outcomes indicated a significant inverse correlation between concentrations of fine particles and fetal growth. The adjusted effect of exposure to P[M.sub.2.5] was reflected in significantly lower mean weight and length at birth and lower mean HC of newborns. The newborns of mothers exposed to higher concentrations of fine particles (above the median of 36.3 [micro]g/[m.sup.3]) showed shorter length at birth by 0.9 cm. The corresponding reductions in HC and birth weight were 0.3 cm and 128.3 g. We estimated from the regression equations that an increase of exposure from 10 to 50 [micro]g/[m.sup.3] of fine particles would reduce length at birth by 1.0 cm. The corresponding reductions of HC and birth weight would be 0.5 cm and 140.3 g, respectively.
Our study showed a significant positive interrelationship in·ter·re·late
tr. & intr.v. in·ter·re·lat·ed, in·ter·re·lat·ing, in·ter·re·lates
To place in or come into mutual relationship.
in between self-reported ETS level and total personal exposure to P[M.sub.2.5], which to a great extent depended on the number of reported cigarettes smoked daily at home. This interrelationship creates difficulties in separating the effect of ETS on the birth outcomes from that attributed to fine particles. However, none of the models with both ETS and P[M.sub.2.5] showed a significant effect of ETS. Moreover, stepwise regression In statistics, stepwise regression includes regression models in which the choice of predictive variables is carried out by an automatic procedure. indicated that adding the ETS variable into the model did not explain better the amount of variability in birth outcomes due to air contamination. Therefore, we think that the effect of ETS confirmed in many previous studies may result from its interrelationship with P[M.sub.2.5]. In studies where the birth outcomes were not controlled by the P[M.sub.2.5] level, the effect of ETS could be demonstrated.
The biologic mechanisms whereby P[M.sub.2.5] might cause adverse pregnancy outcomes are unclear. P[M.sub.2.5] might be a proxy measure of a whole complex of toxic agents present in the environment--including PAHs--that could adversely affect fetal growth. It is well known that fine particles are virtually always present in particle-generating processes, especially combustion processes that generate other toxic agents as well. Typically, the ambient fine particle fraction contains constituents of tobacco and wood smoke, organic compounds, sulfates, metals, and soot (Spengler et al. 2001). Therefore, it would be reasonable to assume that P[M.sub.2.5] represents a wide spectrum of environmental hazards that may be implicated im·pli·cate
tr.v. im·pli·cat·ed, im·pli·cat·ing, im·pli·cates
1. To involve or connect intimately or incriminatingly: evidence that implicates others in the plot.
2. in intrauterine intrauterine /in·tra·uter·ine/ (-u´ter-in) within the uterus.
Within the uterus.
Situated or occuring in the uterus. fetal growth. Air pollutants may affect DNA DNA: see nucleic acid.
or deoxyribonucleic acid
One of two types of nucleic acid (the other is RNA); a complex organic compound found in all living cells and many viruses. It is the chemical substance of genes. , as evidenced by observations that placental placental
pertaining to or emanating from placenta.
the placental separation of maternal and fetal blood which varies in its structure and permeability between the species. DNA adducts are more common in areas with higher levels of pollution (Topinka et al. 1997) and that altered fetal growth has been associated with PAH-DNA adducts (Perera et al. 1998).
Our data indicating that personal exposure to fine particles has a stronger relationship with birth outcomes than does ETS may result from the fact that the measurement of ETS exposure based on interviews with pregnant women could be biased. If respondents underestimated their ETS exposure, then its effect may appear much weaker in comparison with the objective measurements of fine particles. However, the level of fine particles is the function not only of ETS, which is the major source of indoor pollution, but also of PM generated from other sources such as fossil fuel fossil fuel: see energy, sources of; fuel.
Any of a class of materials of biologic origin occurring within the Earth's crust that can be used as a source of energy. Fossil fuels include coal, petroleum, and natural gas. combustion.
Another potential limitation of our study comes from the fact that personal monitoring of exposure to fine particles among pregnant women was performed over the short period of 48 hr in the second trimester of pregnancy. However, to evaluate the correlation between the level of P[M.sub.2.5] measured over 48 hr in the second trimester of pregnancy with those in the second and the third trimesters, a series of repeated measurements in each trimester trimester /tri·mes·ter/ (-mes´ter) a period of three months.
A period of three months.
The first third or 13 weeks of pregnancy. was carried out in the subsample sub·sam·ple
A sample drawn from a larger sample.
tr.v. sub·sam·pled, sub·sam·pling, sub·sam·ples
To take a subsample from (a larger sample). of 51 pregnant women who were recruited in the first trimester Noun 1. first trimester - time period extending from the first day of the last menstrual period through 12 weeks of gestation
trimester - a period of three months; especially one of the three three-month periods into which human pregnancy is divided . The concentration of P[M.sub.2.5] (mean [+ or -] SD) in the second trimester was 44.4 [+ or -] 46.5 [micro]g/[m.sup.3], but it was not significantly different from the mean concentration in the first trimester (46.2 [+ or -] 34.0 [micro]g/[m.sup.3]) or in the third trimester (35.9 [+ or -] 35.3 [mciro]g/[m.sup.3]). The latter results suggest that the mean levels of fine particles were rather stable over the whole pregnancy. This provides some confidence that the measurements of personal level of exposure to fine particles taken in the second trimester may also be representative for other pregnancy periods.
We could also demonstrate that total personal exposure to P[M.sub.2.5] measured over 48 hr correlated well with the P[M.sub.10] concentrations obtained from the monitors of the municipal air pollution network of Krakow, which were located in the residence areas of the subjects under study (Figure 2). We observed consistency between monthly means of P[M.sub.10] measured by the local ambient monitors and the monthly means of total personal exposure to fine particles measured over 48 hr in the second trimester. This suggests that the extrapolation (mathematics, algorithm) extrapolation - A mathematical procedure which estimates values of a function for certain desired inputs given values for known inputs.
If the desired input is outside the range of the known values this is called extrapolation, if it is inside then of ambient measurements to personal exposure may be reasonably approximated. However, the extent to which the ambient measurements reflect the individual exposure level may be different in various populations. First, it would depend largely on the quality of the ambient network Ambient Networks is a network integration solution to the modern-day problems of switching from one network to the other in order to keep in contact with the outside world. of air pollution stations and its appropriate coverage of the given residency areas. Besides different lifestyles and mobility of women over the study period, substantial seasonal changes in air pollution due to weather and meteorologic me·te·or·ol·o·gy
The science that deals with the phenomena of the atmosphere, especially weather and weather conditions.
[French météorologie, from Greek conditions may be significant.
[FIGURE 2 OMITTED]
In our study, the most important confounders of the birth outcomes such as the presence of chronic diseases or active tobacco smoking by mothers in pregnancy have been removed through entry criteria. Other risk factors thought to affect the probability of delivery of newborns with lower growth, such as maternal height or prepregnancy weight, gestation age, sex of child, and season of birth, were also accounted for in the analysis.
Over the last decades there has been growing concern over the health effects associated with air pollution. The studies were concerned mainly with morbidity and mortality Morbidity and Mortality can refer to:
adj. delivery (Xu et al. 1995; Yang et al. 2002) and LBW (Wang et al. 1997). Several studies observed an association of TSP and S[O.sub.2] with LBW and found increased risk of IUGR in a highly polluted region in the Czech Republic (Bobak and Leon 1999; Dejmek et al. 1999, 2000; Sram 1999). Ritz and Yu (1999) found that high concentrations of CO and P[M.sub.10] during the last trimester of pregnancy may increase the risk of LBW for term babies. Our prior study also showed that, after controlling for dietary and smoking sources of the pollutants, PAH-DNA adducts in cord blood cord blood
Blood present in the umbilical vessels at the time of delivery. were inversely associated with birth weight, length, and HC (Perera et al. 1998). In contrast, in a study performed in southern Sweden, Landgren (1996) could not confirm the hypothesis that air pollution affected the incidence of short gestation and LBW. Some researchers (Bhopal et al. 1994; Smrcka and Leznarova 1998) found no association between either residential proximity to a coking plant or major steel and petrochemical industries and birth outcomes in the United Kingdom. The study period, size of the population, and number of cases were large. However, Axelsson and Molin (1988) found that the miscarriage rate was slightly elevated in areas exposed to emissions from petrochemical industries. None of the studies used personal monitors of P[M.sub.2.5] in the assessment of exposure.
The results of our study are of public concern because adverse birth outcomes have been associated in other studies with more health problems and reduced cognitive development in childhood (Perera et al. 2002). Follow-up of the cohort will permit determination of the longer-term sequels of prenatal exposures and adverse birth outcomes. The results of our study may have implications not only for the health and development of children but also for adult health. Epidemiologic studies in children indicate that prenatal hazards that restrict fetal growth may be associated with small but measurable delays in motor and social development through childhood and reduced cognitive development (Bacharach and Baumeister 1998; Hack et al. 1991; Hediger et al. 2002; Saigal 2000). There is also evidence of associations between birth size and future development of adult diseases, such as type 2 diabetes type 2 diabetes
See diabetes mellitus. and coronary artery disease coronary artery disease, condition that results when the coronary arteries are narrowed or occluded, most commonly by atherosclerotic deposits of fibrous and fatty tissue. (Godfrey and Barker 2001; Phillips 2000). It is believed that these associations arise as a result of the phenomenon of "programming," which involves persisting changes in structure and function caused by environmental factors during critical and vulnerable periods of early development. However, other explanations, including the operation of genetic factors and programming of certain endocrine axes, have also been suggested to explain this observation.
Our study provides convincing epidemiologic evidence based on a cohort that prenatal exposure resulting from high personal maternal exposure to fine particles is associated with adverse effects on the developing fetus. These results indicate the need to reduce ambient fine particulate concentrations. However, further research should help establish possible biologic mechanisms explaining the observed relationship.
Table 1. Characteristics of the study sample by P[M.sub.2.5] level of personal exposure during pregnancy (mean [+ or -] SD). Low level (a) High level (b) Variable (n = 180) (n = 182) Mother's age 28.1 [+ or -] 3.4 28.1 [+ or -] 3.9 Mother's height (cm) 164.7 [+ or -] 5.3 165.3 [+ or -] 6.0 Mother's weight (kg) 58.6 [+ or -] 10.2 58.3 [+ or -] 7.6 Gestational age (weeks) 39.6 [+ or -] 1.3 39.4 [+ or -] 1.4 Length at birth (cm) 55.1 [+ or -] 2.7 * 54.2 [+ or -] 2.6 Birth weight (g) 3504.3 [+ or -] 471.1 * 3376.0 [+ or -] 453.1 HC at birth (cm) 34.1 [+ or -] 1.5 * 33.8 [+ or -] 1.4 (a) Low level, [less than or equal to] 36.3 [micro]g/[m.sup.3]. (b) High level, > 36.3 [micro]g/[m.sup.3]. * Significantly higher (analysis of variance, p < 0.05) compared with the group with higher exposure to P[M.sub.2.5]. Table 2. Regression summary of dependent variable (birth weight) on log P[M.sub.2.5] exposure and confounding variables (number of pregnancies, height and prepregnancy weight of mother, sex of newborn, and gestational age). (a) Variable Coefficient 95% CI Intercept -4876.72 Education (years of schooling) 10.886 -3.814 to 25.586 No. of pregnancies 61.451 13.121 to 109.781 Maternal height (cm) 10.958 3.278 to 18.638 Prepregnancy weight (kg) 9.743 4.867 to 14.619 Gestational age (weeks) 160.288 130.575 to 190.001 Sex of child -212.802 -293.914 to -131.691 Season Autumn -63.658 -182.217 to 54.900 Winter 49.179 -67.036 to 165.395 Spring 23.544 -92.276 to 139.363 Log P[M.sub.2.5] -200.821 -385.968 to -15.674 ETS 32.008 -91.554 to 155.569 Variable t-Value p -Value Intercept Education (years of schooling) 1.48 0.14 No. of pregnancies 2.54 0.01 Maternal height (cm) 2.85 0.00 Prepregnancy weight (kg) 4.00 0.00 Gestational age (weeks) 10.79 0.00 Sex of child -5.25 0.00 Season Autumn -1.07 0.28 Winter 0.85 0.40 Spring 0.41 0.68 Log P[M.sub.2.5] -2.17 0.03 ETS 0.52 0.60 CI, confidence interval. (a) R = 0.588, [R.sup.2] = 0.334. Table 3. Regression summary of dependent variable (length at birth) on log P[M.sub.2.5] exposure (continuous) and confounding variables (number of pregnancies, height and prepregnancy weight of mother, sex of newborn, and gestational age). (a) Variable Coefficient 95% CI Intercept 13.824 Education (years of schooling) 0.021 -0.070 to 0.111 No. of pregnancies 0.267 -0.032 to 0.566 Maternal height (cm) 0.067 0.020 to 0.115 Prepregnancy weight (kg) 0.040 0.010 to 0.070 Gestational age (weeks) 0.792 0.608 to 0.975 Sex of child -1.150 -1.652 to-0.649 Season Autumn -0.464 -1.197 to 0.269 Winter 0.068 -0.650 to 0.787 Spring -0.063 -0.779 to 0.654 Log P[M.sub.2.5] -1.439 -2.583 to-0.294 ETS -244.000 -1.008 to 0.520 Variable t-Value p-Value Intercept Education (years of schooling) 0.45 0.65 No. of pregnancies 1.79 0.07 Maternal height (cm) 2.83 0.00 Prepregnancy weight (kg) 2.66 0.01 Gestational age (weeks) 8.62 0.00 Sex of child -4.59 0.00 Season Autumn -1.27 0.21 Winter 0.19 0.85 Spring -0.17 0.86 Log P[M.sub.2.5] -2.51 0.01 ETS -0.64 0.52 CI, confidence interval. (a) R = 0.518, [R.sup.2] = 0.262. Table 4. Regression summary of dependent variable (HC at birth) on log P[M.sub.2.5] exposure (continuous) and confounding variables (number of pregnancies, height and prepregnancy weight of mother, sex of newborn, and gestational age). (a) Variable Coefficient 95% CI Intercept 17.266 Education (years of schooling) 0.043 -0.006 to 0.092 No. of pregnancies 0.186 0.025 to 0.347 Maternal height (cm) 0.028 0.002 to 0.053 Prepregnancy weight (kg) 0.026 0.009 to 0.042 Gestational age (weeks) 0.301 0.202 to 0.400 Sex of child -0.782 -1.052 to -0.511 Season Autumn -0.020 -0.416 to 0.375 Winter 0.111 -0.277 to 0.498 Spring 0.134 -0.253 to 0.520 Log P[M.sub.2.5] -0.729 -1.347 to -0.112 ETS 0.151 -0.261 to 0.563 Variable t-Value p-Value Intercept Education (years of schooling) 1.76 0.08 No. of pregnancies 2.31 0.02 Maternal height (cm) 2.17 0.03 Prepregnancy weight (kg) 3.14 0.00 Gestational age (weeks) 6.08 0.00 Sex of child -5.78 0.00 Season Autumn -0.10 0.92 Winter 0.57 0.57 Spring 0.69 0.49 Log P[M.sub.2.5] -2.36 0.02 ETS 0.73 0.46 CI, confidence interval. (a) R = 0.472, [R.sup.2] = 0.214.
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Wieslaw Jedrychowski, (1) Ivona Bendkowska, (2) Elzbieta Flak, (1) Agnieszka Penar, (1) Ryszard Jacek, (1) Irena Kaim, (3) John D. Spengler, (4) David Camann, (5) and Frederica P. Perera (2)
(1) Epidemiology and Preventive Medicine preventive medicine, branch of medicine dealing with the prevention of disease and the maintenance of good health practices. Until recently preventive medicine was largely the domain of the U.S. , Medical College, Jagiellonian University, Krakow, Poland; (2) Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, New York, New York, USA; (3) Obstetrics and Gynecology obstetrics and gynecology
Medical and surgical specialty concerned with the management of pregnancy and childbirth and with the health of the female reproductive system. , Medical College, Jagiellonian University, Krakow, Poland; (4) Department of Environmental Health, School of Public Health, Harvard University, Boston, Massachusetts, USA; (5) Southwest Research Institute Southwest Research Institute (SwRI), headquartered in San Antonio, Texas, is one of the oldest and largest independent, nonprofit, applied research and development (R&D) organizations in the United States. Founded in 1947 by Thomas Slick, Jr. , San Antonio, Texas “San Antonio” redirects here. For other uses, see San Antonio (disambiguation).
San Antonio is the second most populous city in Texas, the third most populous metropolitan area in Texas, and is the seventh most populous city in the United States. As of the 2006 U.S. , USA
Address correspondence to W. Jedrychowski, Epidemiology and Preventive Medicine, Medical College, Jagiellonian University, 7A, Kopernika St., Krakow, Poland. Telephone: 48-12-423-1003. Fax: 48-12-422-8795. E-mail: firstname.lastname@example.org
The study received funding from 5 ROI (Return On Investment) The monetary benefits derived from having spent money on developing or revising a system. In the IT world, there are more ways to compute ROI than Carter has liver pills (and for those of you who never heard of that expression, it means a lot). ES0165 from the National Institute of Environmental Health Sciences The National Institute of Environmental Health Sciences (NIEHS) is one of 27 Institutes and Centers of the National Institutes of Health (NIH),which is a component of the Department of Health and Human Services (DHHS). The Director of the NIEHS is Dr. David A. Schwartz. and from the Gladys and Roland Harriman Foundation.
The authors declare they have no competing financial interests.
Received 2 March 2004; accepted 21 June 2004.