Environmental Health Reviews

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December 2012 Newsletter Article


Radana Gizova RN,*1 Alaedeen Khalil RN*1, Perry Sheffield MD MPH 2, Margaret Rafferty DNP MPH 1 (*share first authorship).
1. New York City College of Technology, The City University of New York
2. Department of Preventive Medicine, Mount Sinai School of Medicine, New York, NY

The death of two children swept from their mothers arms into the raging waters of Hurricane Sandy made headlines around the world and caused many to reflect on the implications of climate change. Pediatricians who would like to know more about climate change and its effect on children's health are referred to articles from the Proceedings of the National Academy of Sciences and Environmental Health Perspectives that are briefly summarized below.

From PNAS published online August 6th 2012
Perception of Climate Change
Hansen J., Sato M., & Ruedy R.

Patterns in global warming are difficult to discern because regional weather and climate conditions tend to fluctuate on a daily and yearly basis. It is difficult to convince the public that climate change exists because they expect variations in weather and "perfect storms". This research utilized data from the Goddard Institute for Space Studies (GISS) which examined the seasonal mean temperature variability between 1951- and 1980. The research found that radical weather anomalies, especially hot summers, are growing more common as a result of global warming. The authors estimate that the earth's warming will further perpetuate more extreme temperature anomalies that can have devastating effects on plant, animal and human life. The authors discussed the importance of increasing public perception to recent trends in global +warming because increased awareness will initiate the actions necessary to help curtail the emission of green house gases.

From Environ Health Perspect. 2011 March 119 (3) 291-298.
Global Climate Change and Children's Health: Threats and Strategies for Prevention
Sheffield P. E. & Landrigan. P.J.

The article analyzed the effects of climate change on children's health and suggested methods to mitigate these effects. Climate change places children at higher risk for malaria, dengue disease, increased diarrheal and respiratory disease and increased morbidity and mortality from extreme weather. Emerging research is quantifying that especially hot summers will increase pregnancy complications and renal effects. Preexisting social and economic disparities will be exacerbated by worsened poverty, malnutrition and threats to human habitation. The current burden of climate change related disease falls disproportionately (over 80%) on children globally. The authors stress the importance of implementing preventive measures in order to reduce the children's potential health outcomes related to climate change. More research is needed to refine our understanding of the complex relationship between climate change and children's health status. The needed research would require quantification of existing impacts and projection of future impacts. The authors suggest that further analysis of climate change on children's health is crucial and that the children's environmental health indicators proposed by the World Health Organization (WHO) be implemented by researchers worldwide. They also suggest that health effect assessment might serve as a starting point to create policies that can solve multiple existing problems.

Submitted by
Perry Sheffield

perry.sheffield@mssm.edu

June 2012 Newsletter Article


Semoy Lopez RN 1 Perry Sheffield MD MPH 2 Margaret Rafferty DNP MPH RN 1

  • New York City College of Technology, The City University of New York, Brooklyn, NY
  • Department of Preventive Medicine, Mount Sinai School of Medicine, New York, NY

Indoor Air Pollution from Gas Cooking and Infant Neurodevelopment.
Vrijheid, M., Martinez, D., Aguilera, I., Bustamante, M., Ballester, F., Estarlich, M., Fernandez-Somoano, A., Guxens, M., Lertxundi, N., Martinez, M.D., Tardon, A. & Sunyer, J. Center for Research in Environmental Epidemiology, Barcelona, Spain,
Epidemiology January 2012 Vol 23 No 1

This prospective birth cohort study examined the relationship between indoor air pollution from gas cooking and infant neurodevelopment. Between 50-70% of homes in developed countries have gas stoves. Gas stoves are a common cause of indoor air pollution with emissions that include volatile organic compounds, particulates, carbon monoxide, carbon dioxide, nitric oxide, sulfur dioxide and nitrogen dioxide. These emissions are linked to a host of negative health outcomes.

Conducted in Spain between 2004 and 2008, this study included a sample of 1887 mother-child pairs drawn from the original 2644 mother-child pairs initially enrolled during the first trimester of pregnancy (INfancia y Medio Ambiente). Mothers in their third trimester of pregnancy completed a comprehensive environmental exposures questionnaire. All child participants completed the Bayley Scales of Infant Development prior to 23 months of age and were term births. This study compared the development of children whose homes had gas cookers (natural gas, propane, butane) with those whose homes had electric cookers. The statistical analysis involved a multivariate linear regression model and included twenty six covariates (e.g., maternal cotinine in urine, breastfeeding, paternal education). The results of the study showed that use of gas cookers compared to electric cookers was associated with a decline on the mental development score of the Bayley Scale of Infant Development. This decline was most apparent in those tested after 14 months of age. Use of exhaust fans in the homes that used gas cookers appeared to mitigate against cognitive decline. Adequate intake of antioxidant nutrients (breastfeeding, fish, fruit and vegetable consumption) also appeared to be a protective factor.

The research is an important contribution to our understanding of the effect of indoor air pollution on child neurodevelopment. Counseling families to use appropriate kitchen ventilation, buy pilotless ignition stoves and ensure that gas stoves are properly maintained are important preventive measures. A yellow-tipped flame on a gas stove indicates a maintenance problem - flames should always be blue-tipped.

While this study focuses on a developed country and gas stoves, indoor air pollution from biomass fuels used in lower income countries are an even greater cause of childhood disease, most notably respiratory tract infections. Cooking with wood, coal, and dung are responsible for nearly two million deaths each year primarily among women and children. The Global Alliance for Clean Cookstoves is a global initiative that strives to decrease health hazards related to indoor cooking in the developing world. The findings from this study summarized above call important attention to the potential health risks associated with emissions from modern appliances used in the developed world. Ideally, we can simultaneously move forward as a global public health community to improve indoor air quality the world over.

Submitted by
Perry Sheffield

perry.sheffield@mssm.edu

April 2012 Newsletter
Environmental Health Reviews



Meaza Temesgen-Crawford RN 1 Perry Sheffield MD MPH 2, Margaret Rafferty DNP MPH 1

  • New York City College of Technology, The City University of New York Brooklyn, NY
  • Department of Preventive Medicine, Mount Sinai School of Medicine, New York, NY


Environ Health Perspect. 2012 February. [Epub ahead of print]

Arsenic, Organic Foods, and Brown Rice Syrup.
Jackson, B.P., Taylor, V. F., Karagas, M.R., Punshon, T. & Cottingham, K.L. Trace Element Analysis Laboratory, Department of Earth Sciences, Dartmouth College, Dartmouth Medical School-Section of Biostatistics and Epidemiology, Department of Community and Family Medicine, Department of Biological Sciences, Dartmouth College.

Recent research has found that organic brown rice syrup, like the rice from which it is made, can contain high levels of arsenic (As). Toddler formula, cereal/ energy bars and high energy food used by athletes often use organic brown rice syrup as a sweetener instead of high fructose corn syrup. The investigators hypothesized that organic brown rice syrup which is promoted as "natural" or "organic" was introducing arsenic into the diets of unsuspecting consumers. The authors of this report analyzed foods in an effort to determine how much arsenic was present in these products.

The researchers tested for total arsenic level and extracted for As species in a sample of products purchased off the internet and in local stores in Hanover, New Hampshire. They tested three different organic brown rice syrups, 17 infant/toddler formulas, 27 cereal/energy bars and three high energy products used by endurance athletes. The results showed that products that use organic brown rice syrup as an ingredient contained higher levels of inorganic As (Asi). The researchers were particularly concerned about the arsenic concentrations found in food and drink consumed by young children as they are more vulnerable to health effects given their rapid development and greater pound for pound exposure to contaminated food stuffs.

The toxicity of chronic exposure to Asi is best understood and has been linked to skin lesions, cancer, cardiovascular disease, infant mortality, low birth weight and decreased immune function. The negative health effects associated with shorter term exposures and exposure to organic arsenic also found in some of the foods tested is less studied. This research is an important addition to the emerging literature on arsenic in our food supply and suggests that health-based regulations should be developed for food and beverages not simply water supply.


Tatiana Bovgirya RN 1 Perry Sheffield MD MPH 2, Margaret Rafferty DNP MPH 1

  • New York City College of Technology, The City University of New York Brooklyn, NY
  • Department of Preventive Medicine, Mount Sinai School of Medicine, New York, NY


From Proceedings of the National Academy of Sciences (PNAS) 2011 Vol. 108 No. 51 doi/10.1073/pnas.1109127108

Rice Consumption Contributes to Arsenic Exposure in U.S. Women.
Gilbert-Diamond D., Cottingham K.L. Gruber, J. F., Punshon, T., Sayarath, V., Gandolfi, A.J., Baker, E R., Jackson, B.P., Folt, C.L., & Karagas, M.R. Children's Environmental Health and Disease Prevention Center at Dartmouth

Recent media reports have called attention to the presence of arsenic in our food supply. Scientists from Children's Environmental Health and Disease Prevention Center at Dartmouth in New Hampshire reported a positive association between rice consumption and elevated levels of urinary arsenic excretion in a cohort of pregnant women. Two hundred twenty-nine pregnant women were evaluated at a six-month prenatal visit. The subjects provided a urine sample and completed a three day dietary log that focused on water, seafood, and rice consumption. Water samples from the respondents' homes were also analyzed. The participants were divided into two groups based on rice consumption. Statistical analysis using the nonparametric Wilcoxon rank-sum test compared the median urinary creatinine and arsenic metabolites (MMA/iAs, DMA/MMA and total arsenic) of the "rice eaters" and the "non-rice eaters." The median total urinary arsenic concentration was higher among women who reported rice consumption and had exposure to contaminated tap water. Consumption of as little as 0.5 cups/ day of cooked rice was enough to show a measurable exposure.

The research findings suggest that the U.S. population, especially Asian Americans, non-Hispanic Blacks, and Hispanics, as well as those suffering from celiac disease could be exposed to potentially harmful levels of arsenic due to higher dietary intake of rice. This research shows that besides contaminated drinking water, dietary consumption of rice can also contribute to arsenic exposure which is of particular concern for pregnant woman given the increased vulnerability of the fetus to negative effects from early life exposure to arsenic. More research is needed regarding the variability of arsenic type and concentration in different rice cultivars to better inform rules and regulations regarding allowable arsenic concentration in rice grown and sold in the U.S. Despite incomplete data about the risk from arsenic exposure from rice and rice-derived products, groups such as the national network of Pediatric Environmental Health Specialty Units (PEHSU) are working to develop messaging to the public to help put such findings in context. Find contact information for your regional PEHSU at www.aoec.org/pehsu.

Submitted by
Perry Sheffield

perry.sheffield@mssm.edu

February 2012 Newsletter
Environmental Health Reviews



From J Exposure Sci and Env Epidemiology (2010) 20, 503-515

Indoor airborne fungi and wheeze in the first year of life among a cohort of infants at risk of asthma

Paula F. Rosenbaum, Crawford JA, Anagnost SE, Wang CJK, Hunt A, Anbar RD, Hargrave TE, Hall EG, Liu C, and Abraham JL (From SUNY Upstate Medical University, Syracuse NY)

Mold, common in many communities where flooding, hurricanes, or simply poor repair is the norm, is increasingly becoming a public health concern. A growing body of literature links mold and fungi levels to increases in the frequency of common respiratory conditions, including wheeze and asthma. As we seek to understand the complex interplay of genes and environmental factors that lead to the development of asthma, information about specific mold and fungi agents becomes more important, especially in discussion of prevention efforts.

A recent study conducted by researchers at SUNY Upstate Medical University aimed to elucidate some of these specific agents. Researchers conducted an intensive environmental investigation in the homes of 103 children at risk for developing asthma, given a maternal history of the same. In addition to collecting information about demographic and specific risk factors for wheeze, such as exposure to tobacco smoke in the home, researchers sampled homes for airborne fungi and inspected particulate dust and home conditions. After controlling for season of environmental assessment, known risk factors for wheeze - including exposure to maternal smoking in utero, exposure to smoking at home, and day-care attendance (a surrogate for respiratory infection) - and demographic factors that were confounders, researchers found that high levels of the mold Penicillium were significantly associated with wheeze in the first year of life. Researchers also found that dampness, musty odors, and visible mold were not associated with wheeze, although visible mold was associated with the presence of Penicillium.

Although this study was limited by a small sample size, these results augment the findings of previous studies that suggest that the presence of mold - specifically, Penicillium - contributes to the development of wheeze, and likely in a dose-response relationship. It also suggests that mold levels may be a health concern even in the absence of visible mold, musty odors, and damp conditions.

Submitted by
Lauren Marcewicz, MD

Pediatric Resident, Mount Sinai School of Medicine
New York, NY

April 2011 Newsletter
Environmental Health Reviews



The Impact of Smoke-Free Laws on Asthma

Takaro TK, Krieger J, Song L, Sharify D, Beaudet N. The Breathe-Easy Home: The Impact of Asthma-Friendly Home Construction on Clinical Outcomes and Trigger Exposure. Am J Public Health. 2011;101:55-62.

The recent increase in sustainable, or "green," buildings has been advanced primarily on the potential environmental benefits. The impact of these construction practices on human health, however, has been left largely unexamined. The Breathe-Easy Home (BEH) project is one of the first studies to investigate how energy-efficient and sustainable design features influence human health. In this intervention study, the authors found that moving into a Breathe-Easy home resulted in statistically significant improvements in subjective and objective measures of asthma morbidity.

With a prevalence of 9.1$, asthma is one of the more common chronic diseases of childhood. The etiology of this complex disease is multi-factorial, with genetic, environmental, and infectious elements influencing the development and severity of asthma. Low-income, urban, minority communities often have higher rates of asthma. The authors of this study point out that as much as 40$ of this additional risk may result from the poor condition of the housing stock in these communities. Mold, dust mites, and cockroach allergens are often found in such housing and have all been associated with worsening of asthma symptoms.

To further investigate the relationship between housing and asthma, the authors utilized a natural experiment in which old, deteriorating public housing units in Seattle, WA were demolished in order to construct new, mixed-income units, including the BEH. The relevant respiratory health features of these homes include materials with minimal off-gassing, filtered air ventilation systems, and exterior envelopes that minimize moisture intrusion. In this quasi-experimental design, the intervention group consisted of 34 individuals with clinician-diagnosed persistent asthma who moved into the BEH, while the comparison group consisted of 68 matched individuals with clinician-diagnosed persistent asthma from a previously completed, randomized control trial investigating the impact of community health worker (CHW)-provided education on asthma. Both groups received in-home educational sessions from CHWs, vacuum cleaners, hypoallergenic bedding materials, and cleaning supplies. The authors hypothesized that, compared to education and CHW-support, the BEH would reduce asthma morbidity, healthcare utilization, and indoor allergen triggers while increasing quality of life (QOL).

Study participants completed questionnaires and pulmonary function testing prior to moving into the BEH and then again 1 year later. Clinical outcome measures consisted of a combination of self- or parent-reported questions on asthma exacerbation frequency, rescue medication use, and symptom-free days; healthcare utilization; and quality of life. House dust was tested for dust mite and cat allergens, and fungal mass.

Compared to pre-move values, the BEH group at follow-up showed significant improvements (all p-values <0.05) in asthma-symptom-free days (on average, 3.8 more symptom free days than in preceding 2 weeks), healthcare visits (41.2$ reduction in visits), caretaker QOL, and lung function (FEV1 increased by 0.24 L/min) while there were significant reductions in rescue medication use (number of days used in the preceding 2 weeks decreased by 4.1), nocturnal symptoms (number of nights with symptoms in the preceding 2 weeks decreased by 3.5 nights), and asthma attacks (decreased by 5.1 attacks in the preceding 3 months). However, the comparison group also had significant changes in these measures pre- and post-intervention and there were no statistically significant differences between the two groups, with the exception of fewer nocturnal symptoms in the BEH group. Based on the improvements in symptom-free days, healthcare utilization, and pulmonary function testing, the authors state that both interventions achieved similar results as one year of optimized inhaled corticosteroid use. With the additional features on each house increasing construction cost by $5,000-$7,000, the need for a cost-effectiveness analysis is discussed.

This pilot study highlights the influence that health-centric housing can have on the respiratory health of children and adolescents with asthma. As sustainable building practices become more common, further research will be needed to better evaluate the relationship between human health and these specific construction features versus new housing in general.

Review by Kevin Chatham-Stephens,
Pediatric Environmental Health Fellow,
Mount Sinai School of Medicine

Submitted by
Sheffield, Perry

April 1, 2011

HEPA Air Filters, Secondhand Smoke, and Asthma

Lanphear BP, Hornung RW, Khoury J, Yolton K, Lierl M, Kalkbrenner A. Effects of HEPA Air Cleaners on Unscheduled Asthma Visits and Asthma Symptoms for Children Exposed to Secondhand Tobacco Smoke. Pediatrics 2011;127;93-101.

The health effects of secondhand tobacco smoke (SHS) exposure are numerous. They particularly affect vulnerable populations such as children with asthma. Given the difficulty in attaining substantive reductions in children's exposure to SHS through anticipatory guidance, Lanphear et al. examined the impact of high-efficiency, particulate arresting (HEPA) air filters on healthcare utilization, asthma symptoms, and SHS exposure in children with asthma.

Study participants were recruited from children who received asthma clinical care in the Cincinnati, OH area. Eligibility requirements included being 6 to 12 years old, having clinician-diagnosed asthma, having had one or more clinical visits for asthma exacerbations in the preceding year, and being exposed to five or more cigarettes per day. Utilizing a double-blind design, the authors randomized 225 children to receive either two active or inactive HEPA air cleaners. Each individual had one HEPA air cleaner placed in the home's main room and one in the child's bedroom.

The primary outcome for the study was healthcare utilization, while secondary outcomes consisted of the Child Health Asthma Survey, tobacco smoke exposure, indoor particulate matter levels, and exhaled nitric-oxide (NO) levels. After baseline questionnaires were obtained for each participant, serial assessments were performed every three months for a total of 12 months to collect information on these variables. Serum and hair cotinine levels were performed at baseline, six months, and twelve months.

At baseline, the two groups were statistically similar except for the control group having a greater number of unscheduled asthma visits in the prior three months and higher airborne particulate matter (> 0.3 µm) levels. At the 12 month follow-up, the intervention group had fewer unscheduled visits for asthma care compared to the control group. While the control group had 227 unscheduled visits, the intervention group had 185 such visits, resulting in a difference of 42 visits (95% confidence interval: 1.25–82.75 visits; p = 0.043). This reduction was equivalent to an 18.5% decrease in visits over the study period. When restricting the analysis to families who used the air cleaners greater than 70% of the time, the association became stronger. Air levels of >0.3 µm particles also differed significantly at 12 months, with reductions of 25% in the intervention group and 5$ in the control group. Asthma morbidity, asthma medication use, exhaled NO, and cotinine levels did not differ statistically between the two groups.

With more than 20% of children in the United States being exposed to SHS, a multi-prong approach is needed to reduce the adverse health effects of SHS. This study provides some evidence that HEPA air cleaners may be able to improve the indoor air quality in homes with smokers and decrease unscheduled healthcare utilization for children with asthma but are unlikely to fully mitigate the negative health effects of SHS. Further research is needed to better understand the relationship between air filters, air quality, and asthma morbidity.

Review by Kevin Chatham-Stephens,
Pediatric Environmental Health Fellow,
Mount Sinai School of Medicine

Submitted by
Sheffield, Perry

April 1, 2011



Feburary 2011 Newsletter
Environmental Health Reviews



The Impact of Smoke-Free Laws on Asthma

Dove MS, Dockery DW, Connolly GN. Smoke-Free Air Laws and Asthma Prevalence, Symptoms, and Severity Among Nonsmoking Youth. Pediatrics 2011;127:102-109

Nearly three quarters of the US population lives in a city or county covered by a smoke-free law. Previous evidence has demonstrated lower average blood cotinine levels, a reliable marker for tobacco smoke exposure, among youth living in areas with smoke-free laws. Building on this body of research, this study by Drs. Dove, Dockery and Connolly sought to explore if there is a corollary improvement in certain pediatric conditions traditionally associated with exposure to secondhand smoke (SHS). Consistent with the evidence that SHS can exacerbate asthma severity and that smoke-free laws reduce exposure to SHS, this study found a clear association between fewer asthma symptoms and living in a county without a smoke-free law. These results underscore the importance of legislation in preventing asthma-related morbidity among children. This study supports the public health benefit of extending smoke-free laws to the rest of the country, in order to help prevent asthma exacerbations, thus improving quality of life for children with asthma and lessening the burden of asthma on the health care system.

In the current study, Dove et al. conducted a cross-sectional analysis of data from the 1999-2006 National Health and Nutrition Examination Survey (NHANES). They compared asthma prevalence, severity and symptoms, including persistent wheeze, chronic night cough, and wheeze-medication use, as well as persistent ear infections, among 8800 non-smoking youth ages 3-15 years. They identified whether the youth were from counties with or without smoke-free laws based on data collected by the American Nonsmokers' Rights Foundation. The authors excluded youth self-identified as smokers or who were identified as smokers based on blood cotinine levels, as well as youth who were exposed to SHS in their home due to living with a member of the family who smoked, based on self-report or blood cotinine levels of family members. In their analysis, the authors controlled for several potential confounders, including age, race/ethnicity, family income, and region, as well as maternal and child factors that could be risk factors for asthma or ear infections.

The most important finding of this study is the decrease in frequency of asthma symptoms among children living in areas with smoke-free laws compared to children living in areas without these laws. Specifically, nonsmoking youth living in areas with smoke-free laws had a 33% lower odds (odds ratio: 0.67 [95% confidence interval: 0.48-0.93]) of having reported asthma symptoms. Smoke-free laws also appeared to be associated with lower odds of emergency room visits and asthma attacks, though these results were not statistically significant. The apparent associations between smoke-free locations and prevalence of asthma and persistent ear infections were also not found to be statistically significant. Potential limitations noted by the authors include a possible misclassification bias due to the presence of counties lacking smoke-free laws but containing cities with smoke-free laws.

These findings add yet more evidence to the potential positive public health impacts of extending smoke-free laws to include more regions and settings, underscoring the importance of continued advocacy around this issue. Physicians can turn to their local Pediatric Environmental Health Specialty Units (PEHSUs) to learn more about the evidence base for educating regional and national policy makers about the potential positive pediatric health impacts of smoke-free laws. 
More information can be found on the PEHSU site http://www.aoec.org/pehsu/training.html and at the CDC's site about SHS exposure: http://www.cdc.gov/DataStatistics/archive/second-hand-smoke.html.

Submitted by
Andrea Wershof Schwartz
February 2011

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Three year effect of lead paint hazard removal on blood lead levels

Clark S, Galke W, Succop P, et al. Effects of HUD-supported lead hazard control interventions in housing on children's blood lead. Environ Res. 2010 Dec 21. [Epub ahead of print]

For two decades, state and local governments have benefitted from grants from the US Department of Housing and Urban Development (HUD) to help in the task of eliminating lead-based paint from private homes in low-income areas. These programs have had significant impacts on reducing dust lead levels (DLLs) and blood lead levels (BLLs) in children. This study by Clark et al., evaluating the impact of these grant programs, found that the decreases in DLLs and BLLs persisted to at least three years after a HUD intervention to reduce lead-based paint in a home. The key findings included a sustained reduction in BLLs at three years post intervention, and an effect of the intervention even on children with BLLs of 10 μg/dL and lower pre-intervention, a level at which children were previously thought not to benefit measurably from such interventions.

The purpose of this study was to quantify the effects of the HUD lead hazard control interventions on DLLs and BLLs among children living in affected housing built before 1970. The interventions ranged from repainting old lead paint to complete removal and replacement of the affected building part. Prior to the intervention and then at six month intervals post-intervention up to three years, swipe samples were taken to measure DLLs in the home, and blood samples were collected to quantify BLLs in the children, as well as demographic and household information. Two statistical methods, Repeat measures model (RM) and Structural equation model (SEM) were used to analyze the results and control for potential confounders, such as age, the season in which the sample was collected, and prior incidence of lead poisoning.

The most important findings include the result that children with pre-intervention BLLs of 10 mg/dL or less declined post-intervention, and as such were likely to have benefited from the HUD intervention. Specifically, the authors noted a decrease of 22% among children with pre-intervention BLLs between 6-9 mg/dL. The reductions in mean BLL at one year post-intervention were between 22% and 43% for all pre-intervention BLL categories above 6 mg/dL. The reduction in BLL was sustained at two years, with an average reduction of 37% compared to pre-intervention, and BLLs continued to decline at three years post-intervention.

This large, national study used standardized measure of DLLs and BLLs to quantify the impact of the HUD interventions, and provided a longitudinal follow up of the impact of lead hazard controls. An acknowledged limitation of the study is that BLLs are affected by many factors and routes, including the elimination of lead from gasoline in the USA, and as such it is impossible to attribute the entire decline in BLLs solely to the HUD interventions. Nonetheless, by controlling for several factors, including expected increases in BLLs up to age 12 months and expected decreases after that point, the authors were able to attribute a large portion of the decrease to the interventions themselves. A second limitation noted is the lack of a control group, since it would have been unethical to include children living in hazardous housing without first remediating the problem.

In summary, this paper presents three years of data to support the impact of HUD-funded remediation of homes with hazardous lead-based paint on both home dust lead levels and children's BLLs. It shows that the interventions have positive effects even at relatively low pre-intervention BLLs. Since every increment in blood lead level is associated with decreases in IQ, the public health impact of these interventions goes far beyond the more visible cases of lead poisoning to the more subtle overall cognitive and neurodevelopment of children living in homes with lead-based paint hazards. This study points to the importance of public health interventions to prevent chronic low level lead poisoning, in concert with prevention efforts at the individual level to minimize ingestion of dust, such as mopping and hand-washing. It also provides a reminder to clinicians of the importance of referral for home intervention for children, even with relatively low BLLs, who live in homes built before 1970 that may contain lead-based paint. More information about referral for interventions, see the HUD lead site at www.hud.gov/offices/lead/ and for local lead abatement resources see http://www.leadfreekids.org/ or call The National Lead Information Center Hotline at 1(800) 424-LEAD [5323]. For more information about lead poisoning in general, see the Pediatric Environmental Health Specialty Units (PEHSU) site at http://www.aoec.org/pehsu/training.html.

Submitted by
Andrea Wershof Schwartz
February 2011

December 2010 Newsletter
Environmental Health Reviews



Ambient air pollution exposure and full-term birth weight in California. Environmental Health.

Morello-Frosch R, Jesdale BM, Sadd JL, Pastor M. Ambient air pollution exposure and full-term birth weight in California. Environmental Health. 2010; 9 (1):44. doi:10.1186/1476-069X-9-44

Approximately six percent of US births are low birth weight (LBW). LBW is associated with several adverse health outcomes including infant mortality and the development of chronic diseases later in life. Both maternal characteristics, such as race/ethnicity, socioeconomic status, and gestational weight gain, and place-based factors, such as neighborhood quality and social support, have been identified as predictors of LBW. There may also be an association between air pollution and risk of LBW; however, the evidence is inconsistent and the mechanisms are poorly understood. In this study, Morello-Frosch et.al. sought to determine the effects of chronic air pollution exposure during pregnancy on birth weight and risk of LBW among live singleton term infants (>=37 weeks gestation) born in California, 1996-2006 (n=3,545,177).

Ambient concentrations of air pollution were assessed using both California and federal monitoring data, the California Aerometric Information Reporting System (CalAIRS) and the Environmental Protection Agency's Air Quality System (AQS), respectively. Measured pollutants included particulate matter less than 2.5 um in aerodynamic diameter (PM2.5), particulate matter less than 10 um in aerodynamic diameter (PM10), coarse particulate matter (PMcoarse), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone. Tract and ZIP Code geocoded birth data was from the California Department of Health Services Natality files for 1996-2006. The analysis was restricted to live singleton term births with information on birth weight, sex, date of birth, maternal education, parity and maternal age. LBW was defined as birth weight <2500 grams.

Multivariate analyses were adjusted for maternal factors: age, education, race/ethnicity, and birth place; temporal factors: marital status, parity, Kotelchuk index of prenatal care adequacy, and presence of pregnancy risk factors (anemia, diabetes, chronic/pregnancy-associated hypertension, and herpes); and measures of neighborhood socioeconomic status using the 2000 census. Average concentrations during pregnancy for CO, NO2, ozone, PM10, PM2.5, and PMcoarse within a 10 kilometer radius of the tract or ZIP Code of the mother's residence were associated with lower birth weights; -5.4 g (95%CI: -6.8, -4.1) per parts per million (ppm) CO, -9.0 g (95%CI:-9.6, -8.4) per parts per hundred million (pphm) NO2, -5.7 g (95%CI: -6.6, -4.9) per pphm ozone, -7.7 g (95%CI: -7.9, -6.6) per 10 ug/m3 PM10, -12.8 g (95%CI: -14.3, -11.3) per 10 ug/m3 PM2.5, and -9.3 g (95%CI: -10.7, -7.9) per 10 ug/m3 PMcoarse. Higher odds of LBW were found per pphm NO2 (adjusted odds ratio (AOR): 1.03; 95%CI: 1.02-1.04), per ppm CO (AOR: 1.04; 95%CI: 1.02-1.06), and per 10 ug/m3 PM2.5 (AOR: 1.04; 95%CI: 1.02-1.07). These estimates were robust to further adjustment for co-pollutants (with the exception of CO) and full pregnancy exposures were similar to those generated from trimester-level exposures. There was no evidence for effect measure modification by neighborhood level poverty rate; however, after stratification by maternal race, lower birthweights were associated with PM2.5 and PMcoarse exposure among African Americans.

An acknowledged limitation to the study is that the researchers were unable to adjust analyses for maternal prenatal smoking behavior, a known predictor of low birthweight. Other limitations include an inability to account for residential mobility during pregnancy (since maternal geographical locations during pregnancy were based on birth record data); ambient air pollution was a surrogate for personal exposure and did not include indoor pollutant levels, occupational or transportation exposures, or other activities not occurring in the home neighborhood; and measurement error due to air pollution exposure assessment methods. Overall, the results from this study show a modest association between ambient air pollution and lower birthweight, which are consistent with those from previous studies. Though the effect estimates are weaker than those associated with other exposures, such as maternal prenatal smoking, air pollution represents a modifiable environmental exposure and may be especially problematic in other countries where air pollution levels tend to be much higher than those observed in California.

Surveillance of Development and Behavior in Children under Five

Submitted by
Andrea Deierlein, PhD MPH MS

Pediatric Environmental Health Fellow
Department of Preventive Medicine
Mount Sinai School of Medicine, New York, NY
12/1/2010

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Prenatal Organochlorine Exposure and Behaviors Associated with ADHD in School-Aged Children

Sagiv SK, Thurston SW, Bellinger DC, Tolbert PE, Altshul LM, Korrick SA. Prenatal Organochlorine Exposure and Behaviors Associated with Attention Deficit Hyperactivity Disorder in School-Aged Children. Am J Epidemiol. 2010;171:593-601. doi:10.1093/aje/kwp427

Organochlorines, which include polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE), are environmentally persistent contaminants that can cross the placenta and are associated with health risks to the fetus, including neurobehavioral disorders. Attention deficit hyperactivity disorder (ADHD) affects approximately 5-10% of children and is the most common neurobehavioral disorder. Previous literature provides some evidence for an association between PCB levels and attention and impulsivity measures, however, an association between p,p'-DDE exposures and ADHD has yet to be reported. In this study, Sagiv et.al. prospectively investigated the association between prenatal PCB and p,p'-DDE exposures and childhood ADHD behaviors.

Participants were children born in 1993-1998 to mothers residing near a PCB-contaminated harbor in New Bedford, Massachusetts (n=573). Umbilical cord blood samples were collected at birth and four organochlorine exposures were measured: 1) the sum of all 51 measured PCB congeners, 2) the sum of 4 prevalent PCB congeners (118, 138, 153, and 180), 3) the computed toxic equivalent of 5 dioxin-like mono-ortho PCB congeners (to investigate a potential distinct biologic mechanism for the effect of dioxin-like congeners on neurodevelopment); and 4) p,p'-DDE. These values were relatively low compared to those from other population-based studies of PCB exposures. ADHD-like behaviors in the children at ~8 years were assessed using a teacher-administered rating scale, the Conners' Rating Scale for Teachers (CRS-T). Four subscales from the CRS-T were used: 1) Conners' ADHD Index, 2) Diagnostic and Statistical Manual of Mental Disorders, Fourth Addition (DSM-IV) Inattentive, 3) DSM-IV Hyperactive Impulsive, and 4) DSM-IV Total (both subtypes combined). Multivariable regression analyses were used to determine the associations between these four behavioral outcomes with 3 PCB measures and p,p'-DDE. The following covariates were considered in analyses: child's age and sex; maternal age, marital status, smoking during pregnancy, alcohol consumption during pregnancy, local fish consumption during pregnancy, and illicit drug use; and household income and quality of the home environment.

In covariate-adjusted models there were consistent positive associations between organochlorines and increased ADHD-like behaviors. Children's lead exposure did not confound the observed associations and inclusion of multiple organochlorine exposures in the model only slightly attenuated effect estimates. The change in CRS-T scores associated with an increase from the 5th percentile to the 95th percentile of organochlorine exposure was also higher, ranging from 1.1 to 2.4-point increases in scores. When ADHD-like behavior was dichotomized at the 86th percentile (mildly to markedly atypical scores) across quartiles of the sum of 4 PCB exposures, dioxin-like PCBs, and p,p'-DDE, the risk of ADHD-like behaviors increased approximately 26-92% for the highest quartile of exposure compared to the lowest quartile.

A potential limitation of this study is that ADHD-like behaviors were based on scores from a teacher's behavioral rating scale and not clinical diagnosis of ADHD. Additionally, covariate data was missing for 10-15% of the population. The results show moderate associations between organochlorine (PCB and p,p'-DDE) exposures during pregnancy and ADHD-like behaviors in children at ˜8 years.

Submitted by
Andrea Deierlein, PhD MPH MS

Pediatric Environmental Health Fellow
Department of Preventive Medicine
Mount Sinai School of Medicine, New York, NY
12/1/2010

October 2010 Newsletter
Environmental Health Reviews



Adolescents Frequently Exposed to Tobacco Smoke

Kallio K, Jokinen E, Saarinen M, Hämäläinen M, Volanen I, Kaitosaari T, Rönnemaa T, Viikari J, Raitakari OT, Simell O. Arterial intima-media thickness, endothelial function, and apolipoproteins in adolescents frequently exposed to tobacco smoke. Circ Cardiovasc Qual Outcomes. 2010 Mar;3(2):196-203. Epub 2010 Mar 2.

Environmental tobacco smoke (ETS) causes vascular damage in adults and increasing evidence suggests similar changes in exposed children. Perinatal exposure to ETS is associated with increased preclinical risk for atherosclerosis as measured by aortic intima-media thickness (IMT) in neonates and subsequent elevation in cholesterol levels and lipoprotein profiles in the adult offspring; furthermore, ETS has been associated with endothelial damage in children (as measured by flow-mediated dilation of the brachial artery). The effects of ETS on IMT and apolipoprotein levels (a measure of circulating atherogenic lipoproteins) have not been studied in healthy children or adolescents.

Kallio et al. evaluated the effects of ETS on children's preclinical risk for atherosclerosis measured by carotid and aortic IMT, flow-mediated dilation of the brachial artery, and plasma apolipoprotein B (ApoB) levels. This prospective longitudinal cohort study consisted of 494 healthy 13 year olds, who were divided into low-, intermediate-, and high- ETS exposure groups based on cotinine level, a marker of exposure to ETS; cotinine levels were measured yearly from 8 to 13 years of age.

The study was designed as a randomized trial to decrease the exposure of children to known cardiovascular risk factors through dietary and lifetime counseling from 7 months of age and then included a prevention of smoking component which was initiated at 9 years of age. After accounting for confounders (serum lipids, gender, pubertal status, diastolic blood pressure, and body mass index), high-resolution ultrasound scans showed that in comparison to the low-exposure group, the intima-media of the carotid artery and the aorta were thicker in children in the high- and intermediate-exposure groups: carotid measurements were (exposure groups [mean±SD]): low, 0.502±0.079 mm; intermediate, 0.525±0.070 mm; high, 0.535±0.066 mm; P<0.001) and aortic measurements were: low, 0.527±0.113 mm; intermediate, 0.563±0.139 mm; high, 0.567±0.126 mm; P=0.008). Flow-mediated dilation in the brachial artery was significantly reduced in the high-exposure group, (low, 10.43±4.34%; intermediate, 9.78±4.38%; high, 8.82±4.14%; P=0.004). ApoB levels in the high-exposure group were significantly increased in comparison to the low exposure group (low, 0.73±0.17; intermediate, 0.77±0.19; high, 0.79±0.16; P=0.014); the ApoB/ApoA-1 ratios, a predictor of atherosclerosis and endothelial dysfunction in adults, were significantly higher in the high-exposure group (low, 0.56±0.15; intermediate, 0.58±0.17; high, 0.60±0.13; P=0.045).

The authors acknowledge that cotinine levels reflect only recent exposures of tobacco smoke, and are thus not a good proxy for cumulative past exposures (currently, there are no good measures of ETS cumulative exposures). Furthermore, smokers among the cohort can not be fully ruled out, introducing potential bias in the results. Also, among the three exposure groups, there is a significant difference in BMI and diastolic blood pressure, which could suggest other unknown differences that can, independently of ETS, lead to the present results. Interactions between the different cardiovascular risk factors and the preclinical atherosclerotic outcomes were also not discussed.

In conclusion, this is the first study in children that has evaluated ETS on preclinical risk for atherosclerosis; it showed that children with high exposure to ETS had increased risk of IMT in the carotid arteries and the aorta, decreased flow mediated dilation in the brachial artery, and increase in Apo B levels. Further research is needed to assess whether these changes are reversible. These findings support the need for strong regulations on children's exposure to environmental tobacco smoke to reduce subsequent cardio-respiratory disease risk.

Submitted by Mana Mann, MD, MPH Pediatric Environmental Health Fellow
Mount Sinai School of Medicine
New York, NY
10/1/2010




Asthma and Traffic-Related Air Pollution

McConnell R, Islam T, Shankardass K, Jerrett M, Lurmann F, Gilliland F, et al. 2010. Childhood Incident Asthma and Traffic-Related Air Pollution at Home and School. Environ Health Perspect 118:1021-1026. doi:10.1289/ehp.0901232

Asthma is the most common chronic disease during childhood in the United States. According to National Health Interview Survey in 2006, nearly seven million children in the United States have asthma. About two thirds of these children suffer notable disability from asthma and ten million school days are missed yearly due to asthma-related morbidity.

Although increasing evidence suggests that living near heavy traffic is associated with higher rates of asthma, the role of air pollution in the development of new-onset asthma is controversial. The conflicting studies may be the result of incomplete air pollution exposure assessment in children's microenvironments.

Schools in urban environments, for example, are frequently located near streets with high volume traffic flow; in California, for example, almost 10% of public schools are situated within 150 m of roadways with more than 25,000 vehicles daily. McConnell et al. assessed the school environment, a location not well-examined in previous studies as a factor in asthma rates, to determine the inter-relationship of traffic-related pollution at the school, home and community levels on the development of asthma.

The Southern California Children's Health Study is a prospective longitudinal evaluation to determine the effects of air pollution on respiratory health. The cohort consisted of 2,497 children attending kindergarten and first grade that were recruited in 2002-3 from 45 schools in 13 communities. All children with a history of wheeze or asthma were excluded. The children were followed for three years by a yearly questionnaire determining if they had physician-diagnosed asthma (defined as new onset asthma).

A line source dispersion model was used to estimate concentrations of pollutants from local vehicle emissions at homes and schools, and further classified into freeway and non freeway sources. Additionally, ambient levels of O3, NO2, PM10 and PM2.5 were continuously measured from a central site monitor in every community. The study found that the risk of developing asthma increased among children exposed to modeled traffic-related pollution (specifically non-freeway exposures) from roadways near homes (Hazards Ratio (HR) 1.51, 95% CI 1.25-1.82) and near schools (HR 1.45, 95% CI 1.06-1.98), after accounting for confounders. Ambient NO2 levels were also associated with increased risk (HR 2.18, 95% CI 1.18-4.01), but the association was attenuated when traffic-related pollution was added to the model. The authors hypothesize that the significant impact on incidence of asthma from school-related traffic exposure may be due to increased exertion by the child during gym class and recess, leading to greater inhalation of the pollutants.

As the authors point out, the study is limited by the relatively short follow-up period of three years as well as by the retrospective nature of the early-life risk factors questionnaire. Bias could be introduced by asthma misclassification by the physician (especially if was also related to exposure) as well as from loss to follow-up.

The authors conclude that children exposed to higher levels of traffic-related air pollution at both the home and school environments are at increased risk of developing asthma. Traffic-related pollution - and children's ambient air microenvironments in general - should be considered an important public health problem, impacting large populations of children. To limit the exposure of children to traffic-related pollution, both urban development and transportation planning measures need be instated accounting for the location of schools and other areas with high concentration of children and improving the control of traffic exhaust.

Submitted by
Mana Mann

Pediatric Environmental Health Fellow
Mount Sinai School of Medicine
New York, NY
10/1/2010

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Prenatal Exposure to PBDEs and Neurodevelopment

Herbstman JB, Sjõdin A, Kurzon M, Lederman SA, Jones RS, Rauh V, et al. 2010. Prenatal Exposure to PBDEs and Neurodevelopment. Environ Health Perspect 118:712-719. doi:10.1289/ehp.0901340

Polybrominated diphenyl ethers (PBDEs) are flame retardants that are widely used in automobile and airplane parts, in addition to electronics and home furnishings; they are ubiquitous contaminants that have been detected in the environment, animals and humans. PBDEs are not biodegradable and persist in the environment for many decades, accumulating in the fatty tissues of animals. Toxicologic studies have shown that PBDEs may play a role in endocrine disruption as well as developmental neurotoxicity in animals with prenatal exposure.

To study the role of prenatal exposure of PBDEs in children, Herbstman et al. conducted a longitudinal cohort study of 152 U.S. children from birth to age 6 whose mothers were pregnant at the time of the World Trade Center attacks in 2001; the mothers were recruited to participate in a study examining the effects of dust exposure from the towers.

PBDEs were measured from cord blood of 210 infants, 152 of whom were followed for at least one round of neurodevelopmental testing annually at ages 1-4 and 6 years. The authors found that after adjusting for potential confounders, higher concentrations of 3 types of PBDEs (congeners 47, 99, and 100) were associated with lower scores on mental and physical development at all ages studied. Cord blood PBDEs 47, 99, and 100 were found at the following median levels: 11.2 ng/g lipid, 3.2 ng/g lipid, 1.4 ng/g lipid, respectively. These levels are similar to national averages found in women of childbearing age.

The authors acknowledge the study limitation of a relatively small sample size meant that analysis looking at interactions could not be performed. The authors do not comment on the training of the interviewers for the children's developmental assessment; furthermore, it is not mentioned whether the interviewers were blind to the status of the children's PBDE exposure level, potentially introducing bias.

In conclusion, this is the first epidemiologic study showing an adverse developmental outcome in children prenatally exposed to PDBEs. The authors stipulate that the prenatal exposure of mothers to PBDEs was from sources other than just the WTC because the levels in the children were similar to those reported in other U.S. populations. While future studies are needed to confirm these results and elucidate the mechanism of PBDEs' adverse effects, in the meanwhile, using known strategies and researching additional ways to reduce exposure to PBDEs is crucial. For more information and for messages to communicate to patients, see the Pediatric Environmental Health Specialty Unit fact sheet on PBDEs: http://www.aoec.org/PEHSU/documents/pbde_health_professionals.pdf

Submitted by
Mana Mann
Pediatric Environmental Health Fellow
Mount Sinai School of Medicine
New York, NY
10/1/2010

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