Key Findings & Interventions
Checking infant’s weight.
Mothers & Newborns Study, Northern Manhattan / South Bronx
The Center’s largest study is the “Mothers and Newborns Study” in Northern Manhattan and the South Bronx, which is following 725 African-American and Latino pregnant women and their children through early adolescence. Their health is monitored from birth through eleven-twelve years of age. Some current and past exposures of concern include polycyclic aromatic hydrocarbons (PAH), chlorpyrifos, 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.
PAHs 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. 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 CCCEH 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:
Exposure
- Pregnant women and their babies are exposed to multiple common pollutants in air that can harm fetal and child growth and development, affect respiratory health, or increase cancer risk.
- 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. The semi-volatile PAHs averaged higher in the indoor air as compared to outdoor air.
- 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
- Phthalates were detected in 99%-100% of maternal personal air samples. Levels of phthalate exposure were generally higher among CCCEH 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 maternal 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%.
Monitoring toddler’s development.
Fetal Growth and Neurobehavioral Development
CCCEH 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.
PAHs
- 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.
Pesticides
- 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.
- Children prenatally exposed to high levels of chlorpyrifos were significantly more likely than children exposed to low levels to experience delay in both psychomotor and cognitive development, and to show symptoms of attentional disorders, Attention-Deficit/Hyperactivity Disorder (ADHD), and pervasive personality disorder at age 3. 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. Although the EPA banned residential use of chlorpyrifos in 2001, this pesticide is still widely used in agriculture.
- Higher prenatal levels of pesticide cis-permethrin were associated with early cough. Higher levels of pesticide diazinon, paradoxically, were associated with reduced cough, wheeze, and IgE.
- 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 pyrethroid synergist, have increased in personal air samples collected during pregnancy. Also 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.
Secondhand Smoke
- 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.
Phthalates
- 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.
Polybrominated Diphenyl 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.
Asthma
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.
- 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.
- Combined prenatal exposure to airborne PAHs and postnatal secondhand smoke results in the increased likelihood of respiratory and asthma-like symptoms at one and two years of age and at five to six years of age.
- Not only have we found PAHs to be early risk factors for respiratory problems and asthma, but metabolites of airborne PAHs detected in the urine of 5 year olds are associated with allergic immune responses to mouse proteins.
- 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.
- CCCEH 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 carbon is associated with wheeze and cough in children aged two and younger.
- 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.
- Children who were exposed to acetaminophen 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.
Cancer Risk
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.
- Prenatal maternal exposure to polycyclic aromatic hydrocarbons (PAH) from polluted air is associated with chromosomal abnormalities in cord blood. Chromosomal aberrations have been associated with increased risk of cancer in adults. These results suggest that the carcinogenic process may begin in the womb.
Interventions and Impact on Policy
- CCCEH data on the health effects of air pollution have been used by local and national groups to support clean air policies in New York City. From 1998 to 2006, PAH levels from personal monitoring of pregnant mothers in the cohort decreased significantly over time.
- CCCEH estimated the economic burden of one aspect of developmental delays associated with prenatal secondhand smoke exposure—Early Intervention Services—to be over $50 million per year for New York City Medicaid births and $99 million per year for all New York City births.
- 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.
- 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.
- CCCEH 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.
- From its inception, the Center has worked in partnership with, and provided data to, a Community Advisory Board of health service and environmental advocacy organizations in Northern Manhattan and the South Bronx, including 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.
- 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 CCCEH 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
- The organization of several successful community workshops throughout Northern Manhattan on topics ranging from lead poisoning to pest infestation.