Invited Perspective: Still Beating the Drum—Environmental Health Disparities and Neurodevelopment

The increasing incidence and prevalence of neurodevelopmental disorders (NDDs) in the United States1 has been accompanied by public awareness of how hazardous exposures can harm child development. Parents of children from minoritized groups and low-income households are far more likely to encounter a wide range of hazardous exposures that could adversely affect child development.2–4 However, they are less likely to have the resources necessary to access diagnostic and interventional services if their children experience neurocognitive deficits as a result of exposures in utero or during infancy or early childhood.5,6 Marvin Gaye discussed pollution and public health in his 1971 hit “MercyMercyMe (TheEcology),” but despite decades of executive orders around environmental justice, acknowledgment of inequitable pollution distribution and impacts in historically marginalized communities has only recently begun to garner stakeholder attention and subsequent research funding allocation. The thorough review7 by Payne-Sturges et al. in this issue of Environmental Health Perspectives provides a timely examination of the ways in which previous studies of NDDs in vulnerable and historically marginalized populations approach the issue of disparities. In their review, Payne-Sturges et al. demonstrate that fewer than half of these studies actually evaluated disparities. Most of those that did provided no rationale for their examinations. The authors also present practical suggestions for a) how to improve future research in this area by selecting better options for characterizing race and socioeconomic status, and b) how to best interpret effect modification for environmental epidemiologic studies of health disparities. Payne-Sturges et al. rightfully caution against relying on results frommodels of effect modification to assess health disparities in terms of both exposure distribution and outcome ascertainment. This is because resulting interventions may attempt to tackle only one obstacle and not the myriad of other conditions that could lead to the observed disparities. Considering that a large portion of the studies included in this review focused on lead and air pollution exposures, it is important to note that vulnerable communities housing predominantly marginalized populations are often also underresourced, and mothers and children in these neighborhoods can experience joint and cumulative exposures through proximity to high-traffic roads and industrial facilities, crumbling municipal piping, and suboptimal housing—each of which has shown evidence of adversely affecting neurodevelopment.2 Historical and continued segregation into communities disproportionately burdened with a variety of environmental hazards further increases risk due to repeated toxic exposures.3,4 Furthermore, co-occurring sources of environmental and social factors may interact to increase cumulative risk for NDDs.8 However, most studies included in the review evaluated these time-varying, co-occurring exposures independently. As this review illustrates, children perpetually exposed to known neurotoxicants also tend to receive delayed diagnoses and face barriers to services necessary to overcome these obstacles.9 In addition, impairments in cognitive development and subsequent academic achievement can increase economic hardship.6 Therefore, although many large-scale studies of neurodevelopment, particularly those using medical record abstraction, rely on clinical diagnosis of NDDs, subclinical measures of neurodevelopmental delay and impairment could lend themselves to better ascertainment of effects among children from commonly underserved groups. Although several environmental epidemiologic investigations of neurodevelopment simply adjust for sociodemographic factors that have historically been associated with health disparities (e.g., race, ethnicity, income, education, nationality, resource accessibility) as covariates, Payne-Sturges et al. demonstrate a recent movement toward stratification by these factors. However, measures of individual race and ethnicity may not reliably account for structural racism, which is more commonly observed via differences in housing along with service provision for children with impairments and their families.10 Therefore, studies of racial disparities may be improved by examining area-based measures of structural racism such as percentage of unemployed residents, percentage of rental units, segregation indices, and frequency of police activity.10 The increase in interest in environmental justice issues and health disparities is a welcome shift within environmental health research. However, this has also, unfortunately, led to an influx of projects led by researchers who have not fully considered the complex paradigms and persistent racist structures that lead to the disparities. Some report higher hazardous exposures and increased health risks in marginalized communities only as “data,” with little concern for the people impacted. Furthermore, acquired funding is rarely allocated to diversifying study teams for disparities research or collaborating with community members with lived experience. I believe that intrinsically motivated and collaborative investigations of health disparities better highlight the social inequities that lead to the disproportionate burden of hazardous exposures and disease and focus on better science communication to affected community members along with solutions to improve community health. The longstanding commitment of Payne-Sturges and her team to this area of research shows the power of community engagement, collaboration, and advocacy.11 The work currently in production through Project Targeting Environmental NeuroDevelopment Risks (TENDR), which is a community collaborative project focusing on toxic environmental chemicals and NDDs, has the potential to rigorously examine the evidence on Address correspondence to Aisha S. Dickerson, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St., E7638, Baltimore,MD21212USA. Email: Adicke10@jhu.edu The author declares she has no competing interests to disclose. Received 1 June 2023; Revised 5 August 2023; Accepted 10 August 2023; Published 27 September 2023. Note to readers with disabilities: EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact ehpsubmissions@niehs.nih.gov. Our staff will work with you to assess and meet your accessibility needs within 3 working days.

The increasing incidence and prevalence of neurodevelopmental disorders (NDDs) in the United States 1 has been accompanied by public awareness of how hazardous exposures can harm child development.3][4] However, they are less likely to have the resources necessary to access diagnostic and interventional services if their children experience neurocognitive deficits as a result of exposures in utero or during infancy or early childhood. 5,6arvin Gaye discussed pollution and public health in his 1971 hit "Mercy Mercy Me (The Ecology)," but despite decades of executive orders around environmental justice, acknowledgment of inequitable pollution distribution and impacts in historically marginalized communities has only recently begun to garner stakeholder attention and subsequent research funding allocation.
The thorough review 7 by Payne-Sturges et al. in this issue of Environmental Health Perspectives provides a timely examination of the ways in which previous studies of NDDs in vulnerable and historically marginalized populations approach the issue of disparities.In their review, Payne-Sturges et al. demonstrate that fewer than half of these studies actually evaluated disparities.Most of those that did provided no rationale for their examinations.The authors also present practical suggestions for a) how to improve future research in this area by selecting better options for characterizing race and socioeconomic status, and b) how to best interpret effect modification for environmental epidemiologic studies of health disparities.
Payne-Sturges et al. rightfully caution against relying on results from models of effect modification to assess health disparities in terms of both exposure distribution and outcome ascertainment.This is because resulting interventions may attempt to tackle only one obstacle and not the myriad of other conditions that could lead to the observed disparities.Considering that a large portion of the studies included in this review focused on lead and air pollution exposures, it is important to note that vulnerable communities housing predominantly marginalized populations are often also underresourced, and mothers and children in these neighborhoods can experience joint and cumulative exposures through proximity to high-traffic roads and industrial facilities, crumbling municipal piping, and suboptimal housing-each of which has shown evidence of adversely affecting neurodevelopment. 2 Historical and continued segregation into communities disproportionately burdened with a variety of environmental hazards further increases risk due to repeated toxic exposures. 3,4Furthermore, co-occurring sources of environmental and social factors may interact to increase cumulative risk for NDDs. 8However, most studies included in the review evaluated these time-varying, co-occurring exposures independently.
As this review illustrates, children perpetually exposed to known neurotoxicants also tend to receive delayed diagnoses and face barriers to services necessary to overcome these obstacles. 9n addition, impairments in cognitive development and subsequent academic achievement can increase economic hardship. 6herefore, although many large-scale studies of neurodevelopment, particularly those using medical record abstraction, rely on clinical diagnosis of NDDs, subclinical measures of neurodevelopmental delay and impairment could lend themselves to better ascertainment of effects among children from commonly underserved groups.
Although several environmental epidemiologic investigations of neurodevelopment simply adjust for sociodemographic factors that have historically been associated with health disparities (e.g., race, ethnicity, income, education, nationality, resource accessibility) as covariates, Payne-Sturges et al. demonstrate a recent movement toward stratification by these factors.However, measures of individual race and ethnicity may not reliably account for structural racism, which is more commonly observed via differences in housing along with service provision for children with impairments and their families. 10Therefore, studies of racial disparities may be improved by examining area-based measures of structural racism such as percentage of unemployed residents, percentage of rental units, segregation indices, and frequency of police activity. 10he increase in interest in environmental justice issues and health disparities is a welcome shift within environmental health research.However, this has also, unfortunately, led to an influx of projects led by researchers who have not fully considered the complex paradigms and persistent racist structures that lead to the disparities.Some report higher hazardous exposures and increased health risks in marginalized communities only as "data," with little concern for the people impacted.Furthermore, acquired funding is rarely allocated to diversifying study teams for disparities research or collaborating with community members with lived experience.I believe that intrinsically motivated and collaborative investigations of health disparities better highlight the social inequities that lead to the disproportionate burden of hazardous exposures and disease and focus on better science communication to affected community members along with solutions to improve community health.
The longstanding commitment of Payne-Sturges and her team to this area of research shows the power of community engagement, collaboration, and advocacy. 11The work currently in production through Project Targeting Environmental Neuro-Development Risks (TENDR), which is a community collaborative project focusing on toxic environmental chemicals and NDDs, has the potential to rigorously examine the evidence on Note to readers with disabilities: EHP strives to ensure that all journal content is accessible to all readers.However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented.If you need assistance accessing journal content, please contact ehpsubmissions@niehs.nih.gov.Our staff will work with you to assess and meet your accessibility needs within 3 working days.

Invited Perspective
hazardous exposure disparities through a multidisciplinary lens, with the goal of making effective changes to mitigate these problems.Scientific evidence suggests that the reduction of individual and widespread municipal exposures can improve child development and health. 12In my opinion, we must avoid implementing interventions without stakeholder engagement, while simultaneously tackling the structural barriers that lead to environmental health disparities.Finally, we must use the Equal Protection Clause of the 14th Amendment 13 to protect children from hazardous exposures and simultaneously reduce community exposures through regulation and public health practice.