The Center’s largest study is the Mothers and Newborns Study in New York City (NYC). In 1998, the Center launched a birth cohort and has been following 725 African-American and Latino pregnant women and their children through early adolescence. The mothers and children reside in Northern Manhattan and the South Bronx, areas that are disproportionately burdened by environmental pollution. Sources include diesel bus depots, major commercial roadways, and substandard housing. The children’s health and development are monitored from birth through adolescence.
Some current and past environmental exposures of concern include polycyclic aromatic hydrocarbons (PAH), chlorpyrifos, pyrethroids, secondhand smoke, bisphenol-A (BPA), phthalates, polybrominated diphenyl ethers (PBDEs), and pest allergens. Some, like PAH and second-hand smoke, are mutagenic and carcinogenic; others are endocrine disruptors capable of affecting child growth, development, and health.
PAH are a group of chemicals released into the air during the incomplete burning of fossil fuels such as gasoline, diesel, coal, and other organic substances. Secondhand tobacco smoke contains thousands of toxic chemicals, some of which are known to be cancer-causing. Chlorpyrifos is a toxic pesticide that can be inhaled following the use of spray pesticides indoors, and young children have greater exposure because they spend more time on the floor where pesticides are commonly applied. Chlorpyrifos has since been replaced with another group of chemicals called pyrethroids. Plastics and other consumer products contain chemicals such as BPA and phthalates that can mimic or block natural hormones and thus are capable of disrupting early development. PBDEs are widely used flame retardant compounds that are applied to textiles, building materials, and electronic equipment and are thought to have endocrine disrupting effects. Exposure to pest allergens from cockroaches, dust mites, and rodents can cause serious allergic and asthmatic reactions. Because they co-occur in the urban setting, these contaminants may have cumulative and even interactive effects.
During pregnancy, the pollutants can cross the placenta and expose the developing fetus. Exposure beginning in the womb can result in delays in cognitive development, asthma and other respiratory symptoms, obesity and metabolic disorders, or changes at the molecular level that could increase children’s cancer risk. Children in the Center study cohort are representative of children living in other urban areas, particularly underserved populations that are disproportionately exposed to harmful pollutants. Following is a summary of selected key findings from the Center’s research study:
Click on the links below to jump to our key findings on specific health topics of interest:
- Pregnant women and their babies are exposed to multiple common pollutants in air that can harm fetal and child growth and development and affect respiratory health.
- During the heating season, there is a significant difference between the indoor and outdoor nonvolatile PAH levels. These seasonal differences in concentrations may be due to increased use of fossil fuels during the heating seasons, mixing of emissions sources and different weather conditions.
- PAH were detected in 100% of the personal air samples and PAH-DNA adducts were detected in 42% of cord bloods. The pesticide chlorpyrifos, was detected in 100% of air samples and 71% of cord bloods collected between 1998 and 2001. 40% of children were prenatally exposed to second hand smoke.
- Phthalates were detected in 99%-100% of maternal personal air samples. Levels of phthalate exposure were generally higher among Center cohort women than among women of reproductive age (18-40 years) sampled through the National Health and Nutrition Examination Survey (NHANES).
- Within the NYC cohort, BPA was detected in over 90% of maternal urine samples. BPA was detected in over 95% of the children’s samples, with greater concentrations of BPA found in children at both ages 3 years and 5 years than in mothers.
- Concentrations of PBDEs were found in a majority of cord samples from women who were pregnant during the September 11th attacks at the World Trade Center. Most women had at least one PBDE subtype above the limit of detection, with prevalence for the three most common types ranging from 59.5%-81.4%.
- Using geographic information systems (GIS) technology, investigators analyzed whether living near areas of high traffic density and stationary sources of air pollution is associated with the prevalence of wheeze, asthma, and blood biomarker of allergy from birth through age 5 years. Results suggest that living close to high density of traffic, four-way intersections, highways and commercial buildings is associated significantly with respiratory distress. These findings have broad implications for other urban areas that commonly have high asthma prevalence and exposure to a high density of traffic and stationary air pollution sources.
Center research has shown that prenatal exposures to PAH, pesticides, secondhand smoke, and PBDEs are linked to reduced fetal growth and developmental problems in young children. These findings have important implications for health and learning ability because early developmental delays and attentional/behavioral problems such as Attention-Deficit/Hyperactivity Disorder (ADHD) can affect later school performance.
- Prenatal exposure to PAH reduced birth weight and head circumference in African-American babies born to women who were more highly exposed to the air pollutants. Several studies have reported that reduction in head circumference at birth or during the first year of life correlates with poorer cognitive functioning and school performance in childhood.
- Children with high prenatal exposure to PAH had significantly lower test scores at age 3 on the Bayley test for cognitive development and were more likely to be developmentally delayed.
- Prenatal exposure to PAH at levels encountered in NYC air can adversely affect child IQ scores at 5 years of age. After adjustment for potential confounders, highly exposed children had Full-scale and Verbal IQ scores that were 4.31 and 4.67 points lower compared to less exposed children. These reductions are similar in magnitude to the effects of low-level lead exposure.
- Mothers’ exposure during pregnancy to pollutants created by the incomplete combustion of fossil fuels and other organic material may lead to behavioral problems in their children. Researchers found that within a sample of 215 children monitored from birth, those children with high levels of a pollution exposure marker in their cord blood had more symptoms of attention problems and anxiety/depression at ages 5 and 7 than did children with lower exposure.
- Prenatal exposure to two household pesticides, chlorpyrifos and diazinon, which transfer easily from the mother to her fetus, reduced birth weight by an average of 6.6 ounces – the equivalent of weight reduction seen in babies born to women who smoked.
- Although the EPA banned residential use of chlorpyrifos in 2001, this pesticide is still widely used in agriculture. 3 year old children prenatally exposed to high levels of chlorpyrifos were significantly more likely to experience delay in both psychomotor and cognitive development, show symptoms of attentional disorders, Attention-Deficit/Hyperactivity Disorder (ADHD), and pervasive personality disorder. High exposure was also associated with a 6.5 point decrease in the Psychomotor Development Index and a 3.3 point decrease in the Mental Development Index in 3 year olds. At age 7, IQ was negatively affected with respect to working memory, suggesting that the relationship between prenatal chlorpyrifos exposure and neurodevelopmental deficits among cohort children persists through age seven, with possible longer-term educational implications.
- Pyrethroid insecticides appear to be replacing the organophosphorus insecticides like chlorpyrifos and diazinon for residential pest control among the cohort. Levels of permethrin, a common pyrethroid insecticide, and piperonyl butoxide, a marker of pyrethroid exposure, have increased in personal air samples collected during pregnancy. Following the 2000-2001 EPA restrictions, both reporting of cockroaches in the home and use of spray pesticides during pregnancy have increased. Insect resistance to pyrethroids may be one possible explanation for these trends. Prenatal exposure to piperonyl butoxide was negatively associated with 36-month neurodevelopment. These findings are important in light of increased use of pyrethroid insecticides following the 2000-2001 restrictions on the residential use of organophosphorous insecticides. These results lend further support to the use of Integrated Pest Management (IPM).
- Children prenatally exposed to secondhand smoke – especially children experiencing material hardship (unmet basic needs of food, clothing, and housing) – had significantly reduced scores on tests of cognitive development at two years of age.
- Prenatal exposure to the phthalate DEHP was associated with shorter gestation. Gestational age was shorter by 1.1 days for each log-unit increase in metabolite concentrations and averaged 5.1 days less among the most exposed. Given inconsistencies with prior findings in other study populations, additional research is warranted.
- Higher prenatal exposures to two of types of phthalates significantly increased the odds of motor delay, an indication of potential future problems with fine and gross motor coordination. Among girls, one of the phthalates was associated with significant decreases in mental development. Prenatal exposures to three of the phthalates were also significantly associated with behavior problems including emotionally reactive behavior, anxiety/depression, somatic complaints and withdrawn behavior. These effects differed somewhat by child sex but were statistically significant among both boys and girls.
Polybrominated Dephenyl Ethers (PBDEs)
- In a related World Trade Center cohort study in New York City, prenatal exposure to ambient levels of the flame retardant compounds PBDEs were associated with adverse neurodevelopment effects in young children. Children with higher concentrations of PBDEs in their umbilical cord blood at birth scored lower on tests of mental and psychomotor development at 1-4 and 6 years.
Childhood asthma in urban communities is a serious disease that accounts for a significant proportion of urgent pediatric health care visits. Asthma is a chronic disease of the airways that causes difficulty breathing, and occurs most commonly in people who become sensitized to certain allergens in our environment. People with asthma react to different triggers. Common triggers include air pollution, diesel exhaust particles, viruses, environmental tobacco smoke, cockroach particles, dust mites, cat or dog dander, outdoor pollen, and mold. These exposures also may contribute to the early development of the disease.
Products of Fossil Fuel Combustion (PAH and Metals)
- Not only have we found PAH to be early risk factors for respiratory problems and asthma, but metabolites of airborne PAH detected in the urine of 5 year olds are associated with allergic immune responses to mouse proteins.
- The Center has linked epigenetic alterations associated with prenatal exposure to PAH in cord blood with parental report of asthma by age 5. Epigenetic changes may disrupt the normal functioning of genes by affecting how they are expressed, but do not cause structural changes or mutations in the genes.
- Exposure shortly after birth to ambient metals such as nickel, vanadium, and to carbon is associated with wheeze and cough in children aged two and younger.
Pest and Pet Allergens
- Approximately half the babies in the study have been born with an immune response to cockroach proteins. However, the immune responses to cockroach proteins at age 5 years, not at birth, are associated with allergy and asthma.
- In the Center’s evaluation of the New York City Housing Authority’s intervention to reduce toxic pesticide use in public housing, high cockroach and mouse allergen levels were significantly associated with asthma prevalence among children and adults.
- Developing antibodies to cockroach and mouse proteins is associated with a greater risk for wheeze, hay fever, and eczema in preschool urban children as young as three years of age.
- Cat ownership appeared to protect against current wheeze and rhinitis (stuffy nose) at age 5 years, despite strong associations between cat ownership and sensitization at age 2.
- Combined prenatal exposure to airborne PAH and postnatal secondhand smoke results in the increased likelihood of respiratory and asthma-like symptoms at one to two years of age and at five to six years of age.
- Children who were exposed to acetaminophen (active ingredient in Tylenol) prenatally were more likely to have asthma symptoms at age five. Acetaminophen has become increasingly common among women in pregnancy, which coincided with a doubling of the prevalence of asthma among children. These findings suggest caution in the use of acetaminophen in pregnancy.
Feeling distressed during pregnancy may be associated with asthma symptoms during childhood. Many emotions can occur during pregnancy but if high demoralization is reported, it could impact the risk of your child wheezing, a common symptom of asthma, during childhood. Demoralization denotes nonspecific psychological distress that may result in an individual’s inability to cope with stressful situations.
This study is finding that exposure to air pollution during pregnancy is associated with genetic damage in babies before they are born. This type of genetic damage has been generally associated with increased cancer risk later in life.
- Approximately 40% of babies in the study were born with DNA damage associated with PAH. In other studies such damage has been tied to an increased risk of cancer. Of particular concern, newborns had higher (approximately 10-fold) levels of adducts than mothers per unit of estimated exposure, indicating greater fetal susceptibility and potential risk from these pollutants.
- Prenatal exposure to PAH was linked to structural changes in babies’ chromosomes. Such genetic alterations have been related in other studies to increased risk of cancer in children and adults. Further research shows that prenatal maternal exposure to PAH is associated with abnormalities in cord blood, particularly on chromosome 6, which contains critical regulatory genes. These results suggest that the carcinogenic process may begin in the womb.
- There were marked inter-individual variations among children in response to prenatal exposure to the same level of toxicants, indicating the potential importance of gene-environment interactions in health outcomes. We have identified significant interactions between genetic variance and PAH on these outcomes, suggesting that some individuals are placed at greater risk of environment toxicants and carcinogens. These variations were seen in both the NYC and Polish cohort.
Partnership with WE ACT for Environmental Justice
An important aspect of our research translational work is through our community partnerships. From its inception, the Center has worked in partnership with, and provided data to a Community Advisory and Stakeholder Board of health service and environmental advocacy organizations in Northern Manhattan and the South Bronx in working collaboration with our lead partner, WE ACT for Environmental Justice (WE ACT).
With WE ACT, the Center developed the Healthy Home Healthy Child (HHHC) community education campaign in 2000. The campaign provides families, physicians, and their patients with practical tips for reducing harmful environmental exposures and protecting children’s health, and information on clean air campaigns in the community. HHHC has also provided training workshops for community leaders and health professionals. In 2005 HHHC won the the US EPA’s prestigious Environmental Health Excellence Award for effectively translating the results of our research into usable information.
WE ACT incorporates Center findings into regular education seminars, promotes health events, and supports and translates institutional research for the education of Northern Manhattan residents. The organization developed a citywide network, Our Housing is Our Health, which is comprised of several organizations collaborating to empower communities to mitigate health effects of environmental exposures related to poor-quality housing. WE ACT has also organized a number of briefings, presentations, case-studies for publication, and testimony to public interest groups and government agencies.
Other recent impacts of WE ACT’s work in New York City, informed in part by Center research, include:
- The introduction of the Asthma Free Housing Act by Public Advocate Betsy Gotbaum and City Council member Rosie Mendez in April 2008. The bill seeks to improve indoor air quality in the homes of NYC asthma sufferers
- The coordination of the inaugural taskforce meetings on rodent control with NY State Senator Bill Perkins, and pass BPA law banning the chemical in children’s products and toys.
- Data from the Center has contributed to WE ACT’s 18-year campaign, “Clean Fuel, Clean Air, Good Health.”
- Center findings have informed the Safer Chemical Healthy Families advocacy campaign, a nationwide effort to pass smart federal policies that protect American families from toxic chemicals.
- The Kellogg Foundation identified the WE ACT/Columbia partnership as one of ten community based participatory research (CBPR) projects that document the impact of CBPR on health policy. In a peer-reviewed article published on January 2006, the authors credit the conversion of NYC’s bus fleet to clean diesel and installation by the EPA of permanent air monitors in Harlem and other hot spots as outcomes resulting from the partnership.
- From 1998 to 2006, PAH levels from personal monitoring of pregnant mothers in the cohort decreased significantly over time. The Diesel Emission Reduction Act of 2006 was passed and used as a platform for strengthening the state’s anti-idling regulations for school buses.
- The Center estimated the economic burden of one aspect of developmental delays associated with prenatal secondhand smoke exposure—Early Intervention Services—to be as high as $50 million per year for New York City Medicaid births and $99 million per year for all New York City births.
- We also estimated the annual costs of preschool special education services for low-income NYC children with developmental delay due to PAH exposure. U.S. law requires that states provide preschool special education to all children between the ages of three and five years who exhibit significant delay or disorder related to cognition, communication, adaptive behavior, social-emotional development, or motor development. Researchers estimated costs to be over $13.7 million per year for Medicaid births in NYC. The projected cost supports policies to reduce level of PAH in NYC air.
Pesticides and Integrated Pest Management (IPM)
- Governmental regulations such as the 2000-2001 EPA restrictions on residential use of the organophosphorous insecticides, chlorpyrifos and diazinon, have positive impacts on children’s health. These regulations significantly reduced use of and exposure to these compounds during pregnancy. This was evidenced by a significant drop in levels of chlorpyrifos in cord blood following the ban.
- Despite a regulatory ban on residential use of chlorpyrifos, agricultural applications continue in the US and abroad. In September 2008, at a public hearing of the EPA’s Scientific Advisory Panel, Federal Insecticide, Fungicide and Rodenticide Act (“Scientific Issues Associated with Chlorpyrifos and PON1”), the Panel unanimously recommended that EPA accept the epidemiologic evidence that chlorpyrifos may act as a neurotoxicant in human beings.
- The Center conducted a pilot intervention using Integrated Pest Management (IPM) to reduce pest infestations and residential insecticide exposures among pregnant women living in New York City. Residential IPM is a pest-control method that minimizes exposure to toxic pesticides in the home through the use of lower-toxicity pesticides, such as sticky traps, bait stations, and gels; cleaning; and repairing leaks and holes. Insecticides measured in indoor air samples and in maternal cord blood decreased significantly after the intervention. These pilot data suggest that IPM is an effective strategy for reducing pest infestation levels and the internal dose of insecticides during pregnancy.
- CCCEH has also collaborated with the New York City Housing Authority (NYCHA) and the New York City Department of Health and Mental Hygiene (NYC DOHMH) in the development, implementation, and evaluation of IPM interventions in public housing. The evaluation has shown that IPM is more effective than the conventional use of more toxic pesticides in reducing levels of cockroach and cockroach allergens in apartments.
- In a letter from Mayor Michael Bloomberg in 2009, he stated that Center findings have been employed in securing support for Local Law 37, putting New York at the forefront of safer pest control methods in the United States.