Health and environmental consequences of the world trade center disaster

A pilot study to identify factors associated with frailty within the World Trade Center general responder cohort

BACKGROUND

Given the significant exposures experienced by the World Trade Center (WTC) general responders, there is increasing interest in understanding the effect of these exposures on aging in this population. We aim to identify factors that may be associated with frailty, a clinical syndrome characterized by a decrease in one's reserve that has been linked to poor health outcomes.

METHODS

WTC general responders enrolled in the WTC Health Program aged 50 and older provided informed consent. Validated frailty assessments, the Frailty Phenotype (with the Johns Hopkins Frailty Assessment Calculator) along with the FRAIL scale, categorized nonfrail from prefrail/frail. Fall risk, functional status, and cognition were also assessed. WTC variables, including an identified WTC-certified condition, were utilized. The risk of frailty was estimated using log binomial regression analysis. A 95% confidence interval (CI) was used to estimate the prevalence ratio (PR).

RESULTS

One hundred and six participants were included; 38 (35.8%) were classified as pre-frail or frail. More of the pre-frail/frail group were obese (57.9% vs. 25%; p = 0.004) and had a WTC-certified condition (78.9% vs. 58.8%; p = 0.036). Obesity (PR = 2.43, 95% CI = 1.31, 4.53), a WTC-certified condition (PR = 1.77, 95% CI = 1.09, 2.89), and risk of falling (PR = 1.97, 95% CI = 1.01, 3.84) were independently associated with frailty.

CONCLUSIONS

Obesity and having a WTC-certified condition were found to be risk factors for frailty in our pilot study. Future work may focus on further identifying risk factors for frailty in the larger WTC general responder population.

Self-reported Cardiovascular Disease in Career Firefighters With and Without World Trade Center Exposure

OBJECTIVE

To assess the effect of World Trade Center (WTC) exposure on cardiovascular disease (CVD) in career firefighters. Methods: Firefighters from four US cities completed health questionnaires that provide information about demographics, CVD diagnoses, and CVD risk factors. Firefighters were also compared with respondents of the 2019 National Health Interview Survey. Results: Greater WTC exposure was positively associated with combined coronary artery disease, myocardial infarction, and angina (termed "CAD") when comparing WTC-exposed with non-WTC-exposed firefighters. Compared with the National Health Interview Survey population, firefighters had lower odds of CAD and stroke. Conclusions: An occupationally appropriate comparison is important to mitigate potential bias from the healthy worker effect. While the risk of CVD in WTC-exposed and non-WTC-exposed firefighters was significantly lower than a general US population, we observed an exposure gradient where greater WTC exposure was associated with greater odds of CVD.

The World Trade Center Exposome and Health Effects in 9/11 Rescue and Recovery Workers

In the aftermath of the World Trade Center (WTC) attack, rescue and recovery workers faced hazardous conditions and toxic agents. Prior research linked these exposures to adverse health effects, but mainly examined individual factors, overlooking complex mixture effects. This study applies an exposomic approach encompassing the totality of responders' experience, defined as the WTC exposome. We analyzed data from 34,096 members of the WTC Health Program General Responder, including mental and physical health, occupational history, traumatic and environmental exposures using generalized weighted quantile sum regression. We find a significant association between the exposure mixture index all investigated health outcomes. Factors identified as risk factors include working in an enclosed heavily contaminated area, construction occupation, and exposure to blood and body fluids. Conversely, full-time employment emerged as a protective factor. This exposomics study emphasizes the importance of considering combined exposures. In an era marked by more frequent and severe natural disasters due to the evolving climate crisis, the exposomic framework holds promise as a valuable tool for disaster preparedness.

Cancer incidence in World Trade Center rescue and recovery workers by race and ethnicity

INTRODUCTION

It is unclear whether differences in health outcomes by racial and ethnic groups among World Trade Center (WTC) rescue and recovery workers reflect those of the population of New York State (NYS) or show distinct patterns. We assessed cancer incidence in WTC workers by self-reported race and ethnicity, and compared it to population figures for NYS.

METHODS

A total of 61,031 WTC workers enrolled between September 11, 2001 and January 10, 2012 were followed to December 31, 2015. To evaluate the association between race/ethnicity and cancer risk, Poisson regression analysis was used to estimate hazard ratios (HR) adjusted for WTC exposure, age, calendar year, sex and, for lung cancer, cigarette smoking.

RESULTS

In comparison to Whites, Black workers had a higher incidence of prostate cancer (HR = 1.99, 95% CI = 1.69-2.34) and multiple myeloma (HR = 3.57, 95% CI = 1.97-6.45), and a lower incidence of thyroid (HR = 0.41, 95% CI = 0.22-0.78) and colorectal cancer (HR = 0.57; 95% CI = 0.33-0.98). Hispanic workers had a higher incidence of liver cancer (HR = 4.03, 95% CI = 2.23-7.28). Compared with NYS population, White workers had significantly higher incidence of prostate cancer (HR = 1.26, 95% CI = 1.18-1.35) and thyroid cancer (HR = 1.80, 95% CI = 1.55-2.08), while Black workers had significantly higher incidence of prostate cancer (HR = 1.22, 95% CI = 1.05-1.40).

CONCLUSION

Cancer incidence in WTC workers generally reflects data from the NYS population, but some differences were identified that merit further investigation.

Material and monetary flows of construction and demolition waste and assessment on physical and environmental properties of illegally dumped construction and demolition waste in Hanoi

The main aim of this study is to investigate the material and monetary flows of CDW management and to characterize the distribution of illegally dumped CDW in Hanoi. Construction and demolition waste management has become a source of much concern to the urban authorities and citizens of big cities in Vietnam. It is estimated that 3000 t of CDW were generated per day from construction and demolition activities in Hanoi, but only 45% of the CDW was received at official landfills, while 55% of the CDW was disposed of elsewhere. The consequences of improper waste management are potentially alarming. The study conducted interviews to identify the material and cash flow associated with licensed and unlicensed contractors in CDW classification, transportation, treatment, and disposal, to characterize the distribution of illegally dumped CDW in two districts in Hanoi (urban and suburban districts), and to assess the composition of dumped CDW and environmental assessment of illegally dumped CDW by chemical analyses such as leaching and content tests. The study concluded that illegal dumping was performed mostly by unlicensed private companies. The illegally dumped CDW was mostly composed of mixed materials such as concrete, bricks, stones, and some hazardous materials such as asbestos and gypsum were found. The environmental concern of illegally dumped CDW was mostly dust, blockage of water ways, and inundation of increased suspended solids, whereas the heavy metal leaching concentration of all samples was below the environmental standards in Vietnam.

Towards a Race-Neutral System of Pulmonary Function Test Results Interpretation

It has been observed widely that, on average, Black individuals in the United States have lower FVC than White individuals, which is thought to reflect a combination of genetic, environmental, and socioeconomic factors that are difficult to disentangle. Debate therefore persists even after the American Thoracic Society's 2023 guidelines recommending race-neutral pulmonary function test (PFT) result interpretation strategies. Advocates of race-based PFT results interpretation argue that it allows for more precise measurement and will minimize disease misclassification. In contrast, recent studies have shown that low lung function in Black patients has clinical consequences. Furthermore, the use of race-based algorithms in medicine in general is increasingly being questioned for its risk of perpetuating structural health care disparities. Given these concerns, we believe it is time to adopt a race-neutral approach, but note that more research is urgently needed to understand how race-neutral approaches impact PFT results interpretation, clinical decision-making, and patient outcomes. In this brief case-based discussion, we offer a few examples of how a race-neutral PFT results interpretation strategy will impact individuals from racial and ethnic minority groups at different scenarios and stages of life.

Developmental exposure to polycyclic aromatic hydrocarbons (PAHs): Focus on benzo[a]pyrene neurotoxicity

Polycyclic Aromatic Hydrocarbons (PAHs) are a class of ubiquitous organic compounds produced during the incomplete combustion or pyrolysis of organic material. Dietary source is the main route for PAH human exposure by environmental contamination, food industrial processing or domestic cooking methods. The most studied PAH is benzo[a]pyrene (B[a]P), due to its harmful and multiple effects on human health: in addition to its well-known carcinogenic effects, emerging evidence indicates that B[a]P also induces neurotoxicity earlier and at lower doses than B[a]P-induced carcinogenicity making B[a]P neurotoxicity relevant to human health risk assessment. Developmental neurotoxicity of B[a]P has indeed received increasing attention: both human and experimental studies provide evidence of detrimental effects of prenatal or early postnatal B[a]P exposure, even at low doses. Indeed, in some of the multi-dose animal studies, maximal adverse effects were observed at lower B[a]P doses, according to a non-monotonic dose-response curve typical of endocrine-disrupting compounds. In substantial agreement with epidemiological studies, both rodents and zebrafish developmentally exposed to B[a]P exhibit long-term changes in multiple behavioural domains, in the absence of overt toxicological effects at birth (e.g. body weight and morphologic abnormalities). Notably, most targeted behavioural responses converge on locomotor activity and emotional profile, often, but not always, leading to a disinhibitory/hyperactive profile.

Functional changes in neural mechanisms underlying post-traumatic stress disorder in World Trade Center responders

World Trade Center (WTC) responders exposed to traumatic and environmental stressors during rescue and recovery efforts have a high prevalence of chronic WTC-related post-traumatic stress disorder (WTC-PTSD). We investigated neural mechanisms underlying WTC-PTSD by applying eigenvector centrality (EC) metrics and data-driven methods on resting state functional magnetic resonance (fMRI). We identified how EC differences relate to WTC-exposure and behavioral symptoms. We found that connectivity differentiated significantly between WTC-PTSD and non-PTSD responders in nine brain regions, as these differences allowed an effective discrimination of PTSD and non-PTSD responders based solely on analysis of resting state data. Further, we found that WTC exposure duration (months on site) moderates the association between PTSD and EC values in two of the nine brain regions; the right anterior parahippocampal gyrus and the left amygdala (p = 0.010; p = 0.005, respectively, adjusted for multiple comparisons). Within WTC-PTSD, a dimensional measure of symptom severity was positively associated with EC values in the right anterior parahippocampal gyrus and brainstem. Functional neuroimaging can provide effective tools to identify neural correlates of diagnostic and dimensional indicators of PTSD.

All-cause and cause-specific mortality in a cohort of WTC-exposed and non-WTC-exposed firefighters

OBJECTIVE

To compare mortality rates in World Trade Center (WTC)-exposed Fire Department of the City of New York (FDNY) firefighters with rates in similarly healthy, non-WTC-exposed/non-FDNY firefighters, and compare mortality in each firefighter cohort with the general population.

METHODS

10 786 male WTC-exposed FDNY firefighters and 8813 male non-WTC-exposed firefighters from other urban fire departments who were employed on 11 September 2001 were included in the analyses. Only WTC-exposed firefighters received health monitoring via the WTC Health Programme (WTCHP). Follow-up began 11 September 2001 and ended at the earlier of death date or 31 December 2016. Death data were obtained from the National Death Index and demographics from the fire departments. We estimated standardised mortality ratios (SMRs) in each firefighter cohort versus US males using demographic-specific US mortality rates. Poisson regression models estimated relative rates (RRs) of all-cause and cause-specific mortality in WTC-exposed versus non-WTC-exposed firefighters, controlling for age and race.

RESULTS

Between 11 September 2001 and 31 December 2016, there were 261 deaths among WTC-exposed firefighters and 605 among non-WTC-exposed. Both cohorts had reduced all-cause mortality compared with US males (SMR (95% CI)=0.30 (0.26 to 0.34) and 0.60 (0.55 to 0.65) in WTC-exposed and non-WTC-exposed, respectively). WTC-exposed firefighters also had lower rates of all-cause mortality (RR=0.54, 95% CI=0.49 to 0.59) and cancer-specific, cardiovascular-specific and respiratory disease-specific mortality compared with non-WTC-exposed firefighters.

CONCLUSION

Both firefighter cohorts had lower than expected all-cause mortality. Fifteen years post 11 September 2001, mortality was lower in WTC-exposed versus non-WTC-exposed firefighters. Lower mortality in the WTC-exposed suggests not just a healthy worker effect, but additional factors such as greater access to free health monitoring and treatment that they receive via the WTCHP.

World Trade Center psychological exposures and trauma related disorders: PTSD and adjustment disorders

The relationship between exposure to the World Trade Center (WTC) disaster and elevated rates of trauma related psychiatric illnesses in 9/11 responders and survivors has been well documented. This paper is part of a series to promote the practice of evidence-based medicine when managing persons with WTC-related conditions and focuses on "Trauma and Stressor Related Disorders," a diagnostic category that includes posttraumatic stress disorder (PTSD) and adjustment disorder. It offers background on 9/11-related trauma exposure, a summary of research findings from this cohort, and is followed by brief diagnostic and treatment information from selected clinical practice guidelines.

Substance use and related disorders among persons exposed to the 9/11 terrorist attacks: Essentials for screening and intervention

A growing body of research supports the association between direct exposure to the September 11, 2001, terrorist attacks, increased rates of alcohol and substance use and elevated risk of subsequent diagnosis with trauma-related and substance use disorders. Posttraumatic stress disorder (PTSD) is the most diagnosed psychiatric illness in individuals who witnessed the 9/11 attacks or participated in disaster response efforts, and substance use disorders (SUDs) are highly comorbid with PTSD. The presence of both conditions poses challenges for clinical management and highlights the importance of screening and offering intervention to this at-risk population. This paper provides background on substance use, SUDs, and co-occurring PTSD in trauma exposed populations, describes best practices for identifying harmful substance use, the role of psychotherapy and medication for addiction treatment (MAT), and recommendations for management of co-occurring SUD and PTSD.

Association of Rheumatoid Arthritis with Opioid Pain Medication Overuse among Persons Exposed to the 9/11 World Trade Center Disaster

We examined the association of post-9/11 rheumatoid arthritis (RA) diagnosis with opioid pain medication overuse among enrollees in the World Trade Center Health Registry (WTCHR). Opioid overuse was defined as the self-reported intake of prescribed opioids at a higher dosage or more often than directed in the last 12 months on one of the two most recent WTCHR surveys (2015-2016, 2020-2021). Post-9/11 RA was ascertained through self-reports and subsequently validated following medical record release by the enrollees' physicians or medical records review. We excluded those with self-reported RA that was not validated by their physicians and those who did not report being prescribed opioid pain medication in the last 12 months. Multivariable log-binomial regression was conducted to examine the relationship between post-9/11 RA diagnosis and opioid pain medication overuse, adjusting for sociodemographic characteristics and 9/11-related posttraumatic stress disorder (PTSD) symptoms. Of the 10,196 study enrollees, 46 had confirmed post-9/11 RA. The post-9/11 RA patients were mostly females (69.6% vs. 37.7%), less frequently non-Hispanic White (58.7% vs. 73.2%) individuals, and less often had attained a higher level of education (76.1% vs. 84.4%) compared to those without post-9/11 RA. Opioid pain medication overuse was significantly associated with a post-9/11 RA diagnosis (Adjusted Risk Ratio: 2.13, 95% CI: 1.44-3.17). More research is needed to better understand the use and management of prescribed opioids among WTC-exposed individuals with RA.

Novel approach to studying effects of inhalational exposure on lung function in civilians exposed to the World Trade Center disaster

It is increasingly important to study the impact of environmental inhalation exposures on human health in natural or man-made disasters in civilian populations. The members of the World Trade Center Environmental Health Center (WTC EHC; WTC Survivors) had complex exposures to environmental disaster from the destruction of WTC towers and can serve to reveal the effects of WTC exposure on the entire spectrum of lung functions. We aimed to investigate the associations between complex WTC exposures and measures of spirometry and oscillometry in WTC Survivors and included 3605 patients enrolled between Oct 1, 2009 and Mar 31, 2018. We performed latent class analysis and identified five latent exposure groups. We applied linear and quantile regressions to estimate the exposure effects on the means and various quantiles of pre-bronchodilator (BD) % predicted forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and FEV1/FVC ratio, as well as the resistance at an oscillating frequency of 5 Hz (R5), frequency dependence of resistance R5-20, and reactance area (AX). Compared with Group 5, which had low or unknown exposure and was treated as the reference group, Group 1, the local workers with both acute and chronic exposures, had a lower median of % predicted FVC (-3.6; 95% CI: -5.4, -1.7) and higher (more abnormal) measures of AX at 10th quantile (0.77 cmH2O L-1 s; 95% CI: 0.41, 1.13) and 25th quantile (0.80 cmH2O L-1 s; 95% CI: 0.41, 1.20). Results suggested heterogeneous exposures to the WTC disaster had differential effects on the distributions of lung functions in the WTC Survivors. These findings could provide insights for future investigation of environmental disaster exposures.

A 15-year follow-up study of mortality in a pooled cohort of World Trade Center rescue and recovery workers

INTRODUCTION

Hazardous exposures from the World Trade Center (WTC) terrorist attacks have been linked to increased incidence of adverse health conditions, often associated with increased mortality. We assessed mortality in a pooled cohort of WTC rescue/recovery workers over 15 years of follow-up.

MATERIALS AND METHODS

We analyzed mortality through 2016 in a pooled and deduplicated cohort of WTC rescue/recovery workers from three WTC-exposed cohorts (N = 60,631): the Fire Department of the City of New York (FDNY); the WTC Health Registry (WTCHR); and the General Responder Cohort (GRC). Standardized mortality ratios (SMRs) were estimated to assess mortality vs. the US and NY state populations. Multivariable Cox proportional hazards models were used to examine associations of WTC exposures (date of first arrival, working on the WTC debris pile) with mortality risk.

RESULTS

There were 1912 deaths over 697,943.33 person-years of follow-up. The SMR for all-cause mortality was significantly lower-than-expected, both when using US (SMR 0.43, 95% confidence interval [CI] 0.42-0.45) and NYS (SMR 0.51, 95% CI 0.49-0.53) as reference populations. SMRs were not elevated for any of the 28 major causes of death. Arriving at the WTC site on 9/11-9/17/2001 vs. 9/18/2001-6/30/2002 was associated with 30-50% higher risk of all-cause, heart disease and smoking-related mortality in non-FDNY/non-GRC members. Conversely, arriving on 9/11/2001 vs. 9/18/2001-6/30/2002 was associated with 40% lower all-cause and smoking-related mortality risk in FDNY members. Working on vs. off the WTC pile was associated with an increased risk of all-cause mortality in non-FDNY/non-GRC members (adjusted hazard ratio [aHR] 1.25, 95% CI 1.04-1.50), and cancer-specific mortality in GRC members (aHR 1.39, 95% CI 1.05-1.84), but lower mortality risks were found in FDNY members.

CONCLUSIONS

We did not observe excess mortality among WTC rescue/recovery workers compared with general populations. However, significantly increased mortality risks among some sub-groups with high WTC exposure warrant further investigation.

The vocal dialogue in 9/11 pregnant widows and their infants: Specificities of co-regulation

Mothers who were pregnant and widowed on September 11, 2001, and their 4-6-month infants (in utero on 9/11) were filmed during face-to-face interaction and their vocal dialogues were examined via microanalysis. Mothers were White, well-educated, mean age 34.3 years, and far from the World Trade Center site on 9/11; infants were 4-6 months, half female. We examined the bi-directional, moment-by-moment co-regulation of the timing of vocal dialogue, and particularly turn taking, in mother-infant and stranger-infant interactions, with time-series models. We analyzed the contingent coordination of durations of (1) vocalizations of the turn-holder, and (2) switching-pauses at the moment of the turn exchange. The switching pause is an aspect of the rhythm of the turn-holder who, after taking a turn, yields the floor to the partner through the switching pause. Turn taking is the lynchpin of dialogue, and the bi-directional contingent coordination of the switching-pause regulates the turn exchange. Both partners showed signs of risk and resilience. The 9/11 mothers did not coordinate the timing of turn taking with their infants, a highly unusual finding. In contrast, the 9/11 infants did coordinate the timing of turn taking with their mothers, and with the "stranger," forms of resilience. We propose that the 9/11 mother's difficulty coordinating with the infant's turn taking rhythm is a mode of transmission of her trauma to the infant. This work expands our knowledge of the specificities of co-regulation in the context of the 9/11 trauma.

Mutagenicity of the organic fraction of World Trade Center dust

Most studies of the health effects and chemical characterization of the dust resulting from the catastrophic collapse of the World Trade Center (WTC) on September 11, 2001, have focused on the large inorganic fraction of the dust; however, chemical analyses have identified mutagens and carcinogens in the smaller organic fraction. Here, we determined the mutagenicity of the organic fraction of WTC dust in Salmonella. Only 0.74% of the mass of the particulate matter (PM) <53 μm in diameter was extractable organic matter (EOM). Because the EOM was 10 times more mutagenic in TA100 +S9 than in TA98 +S9 and was negative in TA98 -S9, we inferred, respectively, that polycyclic aromatic hydrocarbons (PAHs) played a role in the mutagenicity and not nitroarenes. In TA98 +S9, the mutagenic potency of the EOM (0.1 revertant/μg EOM) was within the range of EOMs from air and combustion emissions. However, the EOM-based mutagenic potency of the particles (0.0007 revertants/μg PM) was 1-2 orders of magnitude lower than values from a review of 50 combustion emissions and various air samples. We calculated that 37 PAHs analyzed previously in WTC EOM were 5.4% of the EOM mass and 0.04% of the PM mass; some air contained 0.3 μg WTC EOM/m³ (0.02 μg PAHs/m³ ). Populations exposed to WTC dust have elevated levels of prostate and thyroid cancer but not lung cancer. Our data support earlier estimates that PAH-associated cancer risk among this population, for example, PAH-associated lung cancer, was unlikely to be significantly elevated relative to background PAH exposures.

World Trade Center Site Exposure Duration Is Associated with Hippocampal and Cerebral White Matter Neuroinflammation

Responders to the World Trade Center (WTC) attacks on 9/11/2001 inhaled toxic dust and experienced severe trauma for a prolonged period. Studies report that WTC site exposure duration is associated with peripheral inflammation and risk for developing early-onset dementia (EOD). Free Water Fraction (FWF) can serve as a biomarker for neuroinflammation by measuring in vivo movement of free water across neurons. The present case-controlled study aimed to examine associations between WTC site exposure duration as well as EOD status with increased hippocampal and cerebral neuroinflammation. Ninety-nine WTC responders (mean age of 56) were recruited between 2017 and 2019 (N = 48 with EOD and 51 cognitively unimpaired). Participants were matched on age, sex, occupation, race, education, and post-traumatic stress disorder (PTSD) status. Participants underwent neuroimaging using diffusion tensor imaging protocols for FWF extraction. Region of interest (ROI) analysis and correlational tractography explored topographical distributions of FWF associations. Apolipoprotein-e4 allele (APOEε4) status was available for most responders (N = 91). Hippocampal FWF was significantly associated with WTC site exposure duration (r = 0.30, p = 0.003), as was cerebral white matter FWF (r = 0.20, p = 0.044). ROI analysis and correlational tractography identified regions within the limbic, frontal, and temporal lobes. Hippocampal FWF and its association with WTC exposure duration were highest when the APOEε4 allele was present (r = 0.48, p = 0.039). Our findings demonstrate that prolonged WTC site exposure is associated with increased hippocampal and cerebral white matter neuroinflammation in WTC responders, possibly exacerbated by possession of the APOEε4 allele.

The World Trade Center Health Program: an introduction to best practices

More than 20 years have elapsed since the September 11, 2001 (9/11) terrorist attacks on the World Trade Center (WTC), Pentagon and at Shanksville, PA. Many persons continue to suffer a variety of physical and mental health conditions following their exposures to a mixture of incompletely characterized toxicants and psychological stressors at the terrorist attack sites. Primary care and specialized clinicians should ask patients who may have been present at any of the 9/11 sites about their 9/11 exposures, especially patients with cancer, respiratory symptoms, chronic rhinosinusitis, gastroesophageal reflux disease, psychiatric symptoms, and substance use disorders. Clinicians, especially those in the NY metropolitan area, should know how to evaluate, diagnose, and treat patients with conditions that could be associated with exposure to the 9/11 attacks and its aftermath. As such, this issue of Archives contains a series of updates to clinical best practices relevant to medical conditions whose treatment is covered by the WTC Health Program. This first paper in the 14-part series describes the purpose of this series, defines the WTC Health Program and its beneficiaries, and explains how relevant Clinical Practice Guidelines were identified. This paper also reminds readers that because physical and mental health conditions are often intertwined, a coordinated approach to care usually works best and referral to health centers affiliated with the WTC Health Program may be necessary, since all such Centers offer multidisciplinary care.

The Effect of Fire Smoke Exposure on Firefighters' Lung Function: A Meta-Analysis

Firefighters are exposed to a range of harmful substances during firefighting. Exposure to fire smoke has been associated with a decrease in their lung function. However, the cause-effect relationship between those two factors is not yet demonstrated. This meta-analysis aimed to evaluate the potential associations between firefighters' occupational exposure and their lung function deterioration. Studies were identified from PubMed, Web of Science, Scopus and Science Direct databases (August 1990-March 2021). The studies were included when reporting the lung function values of Forced Expiratory Volume in 1 s (FEV₁) or Forced Vital Capacity (FVC). The meta-analyses were performed using the generic inverse variance in R software with a random-effects model. Subgroup analysis was used to determine if the lung function was influenced by a potential study effect or by the participants' characteristics. A total of 5562 participants from 24 studies were included. No significant difference was found between firefighters' predicted FEV₁ from wildland, 97.64% (95% CI: 91.45-103.82%; I² = 99%), and urban fires, 99.71% (95% CI: 96.75-102.67%; I² = 98%). Similar results were found for the predicted FVC. Nevertheless, the mean values of firefighters' predicted lung function varied significantly among studies, suggesting many confounders, such as trials' design, statistical methods, methodologies applied, firefighters' daily exposure and career length, hindering an appropriate comparison between the studies.

Chemical explosion, COVID-19, and environmental justice: Insights from low-cost air quality sensors

OBJECTIVES

To examine the impact of the Intercontinental Terminals Company (ITC) fire and COVID-19 on airborne particulate matter (PM) concentrations and the PM disproportionally affecting communities in Houston using low-cost sensors.

METHODS

We compared measurements from a network of low-cost sensors with a separate network of monitors from the Environmental Protection Agency (EPA) in the Houston metropolitan area from Mar 18, 2019, to Dec 31, 2020. Further, we examined the associations between neighborhood-level sociodemographic status and air pollution patterns by linking the low-cost sensor data to EPA environmental justice screening and mapping systems.

FINDINGS

We found increased PM levels during ITC fire and pre-COVID-19, and lower PM levels after the COVID-19 lockdown, comparable to observations from the regulatory monitors, with higher variations and a greater number of locations with high PM levels detected. In addition, the environmental justice analysis showed positive associations between higher PM levels and the percentage of minority, low-income population, and demographic index.

IMPLICATION

Our study indicates that low-cost sensors provide pollutant measures with higher spatial variations and a better ability to identify hot spots and high peak concentrations. These advantages provide critical information for disaster response and environmental justice studies.

SYNOPSIS

We used measurements from a low-cost sensor network for air pollution monitoring and environmental justice analysis to examine the impact of anthropogenic and natural disasters.

Characteristics of Cancers in Community Members Exposed to the World Trade Center Disaster at a Young Age

The destruction of the World Trade Center (WTC) towers on 11 September 2001 (9/11) released tons of dust and smoke into the atmosphere, exposing hundreds of thousands of community members (survivors) and responders to carcinogens. The WTC Environmental Health Center (WTC EHC) is a federally designated surveillance and treatment program for community members who were present in the New York City disaster area on 9/11 or during the months that followed. WTC EHC enrollment requires exposure to the WTC dust and fumes and a federally certifiable medical condition, which includes most solid and blood cancers. Several studies have described the prevalence and characteristics of cancers in responders and survivors exposed to the WTC dust and fumes as adults. Cancers in those exposed at a young age warrant specific investigation since environmental toxin exposure at a younger age may change cancer risk. We describe the characteristics of 269 cancer patients with 278 cancer diagnoses among WTC EHC enrollees who were young in age (aged 0 to 30) on 9/11. These include 215 patients with a solid tumor (79.9%) and 54 with a lymphoid and/or hematopoietic cancer (20.1%). Among them, 9 patients had a known second primary cancer. A total of 23 different types of cancer were identified, including cancer types rare for this age group. Many were diagnosed in individuals lacking traditional cancer-specific risk factors such as tobacco use. The current study is the first to report specifically on cancer characteristics of younger enrollees in the WTC EHC program.

Myeloma precursor disease (MGUS) among rescue and recovery workers exposed to the World Trade Center disaster

An elevated risk of myeloma precursor disease, monoclonal gammopathy of undetermined significance (MGUS), was identified among Fire Department of the City of New York (FDNY) World Trade Center (WTC)-exposed firefighters. Further investigation was needed to determine if these findings were reproducible in a more heterogeneous WTC-exposed rescue/recovery workers cohort, the Stony Brook University-General Responder Cohort GRC (SBU-GRC). MGUS risk was compared between the cohorts and to published general population estimates from Olmsted County, MN, USA. In this observational seroprevalence study, odds ratios (OR) and age-standardized risk ratios (RR) of MGUS (M-spike and light-chain-MGUS combined), M-spike, and light-chain-MGUS were estimated using logistic regression. Age-standardized prevalences were calculated for white males aged 50–79; RRs were estimated by comparing risk in the WTC-exposed cohort with the Olmsted County screened cohort. SBU-GRC had elevated odds of MGUS compared with FDNY (OR = 1.38; 95%CI = 1.00–1.89). The age-standardized prevalence of MGUS was 9.0/100 persons (95%CI = 7.5–10.6), over two-fold higher than the general population (RR = 2.08; 95%CI = 1.72–2.51); the age-standardized prevalence of light-chain-MGUS was 3.5-fold higher (RR = 3.54; 95%CI = 2.52–4.97). This study adds to mounting evidence supporting an association between WTC/environmental exposures and MGUS among rescue/recovery workers. Access to MGUS screenings for the entire WTC-exposed cohort could allow for treatment interventions that improve survival.

Cancer risk among World Trade Center rescue and recovery workers: A review

Twenty years after the September 11th, 2001 terrorist attacks, the association between exposures present at the World Trade Center (WTC) site and the risk of several specific types of cancer has been reported among rescue and recovery workers. The authors' objective was to conduct an updated review of these data. Most studies have found elevated rates of both prostate and thyroid cancers compared with rates in the general population, and some have reported statistically significant differences for the rates of all cancers as well. Studies including a larger combined cohort of WTC-exposed rescue and recovery workers from 3 main cohorts have since replicated findings for these cancers, with additional years of follow-up. Among this combined cohort, although a lower-than-expected standardized incidence ratio for all cancers was observed, WTC exposure was also related to an increased risk of cutaneous melanoma and tonsil cancer. Importantly, another study found that WTC-exposed rescue and recovery workers who are enrolled in the federally funded medical monitoring and treatment program experienced improved survival post-cancer diagnosis compared with New York state patients with cancer. On the basis of these combined cohort studies, the full effect of WTC exposure on cancer risk is becoming clearer. Consequently, the authors believe that surveillance of those with WTC exposure should be continued, and in-depth analysis of epidemiologic, molecular, and clinical aspects of specific cancers in these workers should be pursued.

Global DNA methylation of WTC prostate cancer tissues show signature differences compared to non-exposed cases

There is increased incidence of prostate cancer (PC) among World Trade Center (WTC)-exposed responders and community members, with preliminary evidence suggestive of more aggressive disease. While previous research is supportive of differences in DNA methylation and gene expression as a consequence of WTC exposure, as measured in blood of healthy individuals, the epigenetics of WTC PC tissues has yet to be explored. Patients were recruited from the World Trade Center Health Program. Non-WTC PC samples were frequency matched on age, race/ethnicity and Gleason score. Bisulfite-treated DNA was extracted from tumor tissue blocks and used to assess global DNA methylation with the MethylationEPIC BeadChip. Differential and pathway enrichment analyses were conducted. RNA from the same tumor blocks was used for gene expression analysis to further support DNA methylation findings. Methylation data were generated for 28 samples (13 WTC and 15 non-WTC). Statistically significant differences in methylation were observed for 3,586 genes; on average WTC samples were statistically significantly more hypermethylated (P = 0.04131). Pathway enrichment analysis revealed hypermethylation in epithelial mesenchymal transition (EMT), hypoxia, mitotic spindle, TNFA signaling via NFKB, WNT signaling, and TGF beta signaling pathways in WTC compared to non-WTC samples. The androgen response, G2M and MYC target pathways were hypomethylated. These results correlated well with RNA gene expression. In conclusion, long-term epigenic changes associated with WTC dust exposure were observed in PC tissues. These occurred in genes of critical pathways, likely increasing prostate tumorigenesis potential. This warrants analysis of larger WTC groups and other cancer types.

Characteristics of Women with Lung Adenocarcinoma in the World Trade Center Environmental Health Center

The destruction of the World Trade Center towers on 11 September 2001 exposed local residents, workers, and individuals in the area (Survivors) to dust and fumes that included known and suspected carcinogens. Given the potential for inhalation of toxic substances and the long latency after exposure, the incidence of lung cancer is expected to increase in WTC-exposed individuals. We describe the characteristics of women WTC Survivors with lung adenocarcinoma who were enrolled in the WTC Environmental Health Center (WTC EHC) between May 2002 and July 2021. A total of 173 women in WTC EHC had a diagnosis of any type of lung cancer, representing 10% of all cancers in women. Most of the lung cancers (87%) were non-small cell carcinomas, with adenocarcinoma (77%) being the most common subtype. Nearly half (46%) of these patients were exposed to dust clouds on 11 September 2001. Race and ethnicity varied by smoking status, as follows: 44% of Asian women compared with 29% of non-Hispanic White women were never-smokers (p < 0.001). There was no significant difference between the pathologic characteristics of adenocarcinomas between never and ever smokers. We also summarize EGFR, ALK, KRAS, ROS-1 and BRAF mutation status stratified by smoking, race and ethnicity. The identification of a relatively high proportion of women never-smokers with lung cancer warrants further investigation into the role of WTC dust exposure.

The Relationship between 9/11 Exposure, Systemic Autoimmune Disease, and Post-Traumatic Stress Disorder: A Mediational Analysis

The relationship between 9/11 exposure, systemic autoimmune disease (SAD) and mental health remains poorly understood. This report builds on a prior analysis of World Trade Center Health Registry data to determine whether 9/11 exposure is associated with higher risk of SAD, and if so, whether post-traumatic stress disorder (PTSD) is a mediating factor and whether the association varies by responder/community member status. The final analytic sample comprised 41,656 enrollees with 123 cases of SAD diagnosed post 9/11 through November 2017. SAD diagnosis was ascertained from survey responses and confirmed by medical record review or physician survey. Logistic regression models were constructed to determine the relationship between 9/11 exposure and PTSD and SAD. Causal mediation analysis was used to determine the mediational effect of PTSD. Each analysis was stratified by 9/11 responder/community member status. Rheumatoid arthritis (n = 75) was the most frequent SAD, followed by Sjögren’s syndrome (n = 23), systemic lupus erythematosus (n = 20), myositis (n = 9), mixed connective tissue disease (n = 7), and scleroderma (n = 4). In the pooled cohort, those with 9/11-related PTSD had 1.85 times the odds (95% CI: 1.21–2.78) of SAD. Among responders, those with dust cloud exposure had almost twice the odds of SAD, while among community members, those with 9/11-related PTSD had 2.5 times the odds of SAD (95% CI: 1.39, 4.39). PTSD was not a significant mediator. Although emerging evidence suggests 9/11 exposure may be associated with SAD, more research is needed, particularly using pooled data sources from other 9/11-exposed cohorts, to fully characterize this relationship.

Global DNA Methylation Profiles in Peripheral Blood of WTC-Exposed Community Members with Breast Cancer

Breast cancer represents the most common cancer diagnosis among World Trade Center (WTC)-exposed community members, residents, and cleanup workers enrolled in the WTC Environmental Health Center (WTC EHC). The primary aims of this study were (1) to compare blood DNA methylation profiles of WTC-exposed community members with breast cancer and WTC-unexposed pre-diagnostic breast cancer blood samples, and (2) to compare the DNA methylation differences among the WTC EHC breast cancer cases and WTC-exposed cancer-free controls. Gene pathway enrichment analyses were further conducted. There were significant differences in DNA methylation between WTC-exposed breast cancer cases and unexposed prediagnostic breast cancer cases. The top differentially methylated genes were Intraflagellar Transport 74 (IFT74), WD repeat-containing protein 90 (WDR90), and Oncomodulin (OCM), which are commonly upregulated in tumors. Probes associated with established tumor suppressor genes (ATM, BRCA1, PALB2, and TP53) were hypermethylated among WTC-exposed breast cancer cases compared to the unexposed group. When comparing WTC EHC breast cancer cases vs. cancer-free controls, there appeared to be global hypomethylation among WTC-exposed breast cancer cases compared to exposed controls. Functional pathway analysis revealed enrichment of several gene pathways in WTC-exposed breast cancer cases including endocytosis, proteoglycans in cancer, regulation of actin cytoskeleton, axon guidance, focal adhesion, calcium signaling, cGMP-PKG signaling, mTOR, Hippo, and oxytocin signaling. The results suggest potential epigenetic links between WTC exposure and breast cancer in local community members enrolled in the WTC EHC program.

Understanding the Role of Persistent Organic Pollutants and Stress in the Association between Proximity to the World Trade Center Disaster and Birth Outcomes

Fetal growth is affected by exposure to both prenatal stress and environmental contaminants. The attacks on the World Trade Center (WTC) resulted in exposure to chemicals and psychological stress amongst New York City residents. We measured prenatal maternal stress and exposure to persistent organic pollutants (polybrominated diphenyl ethers, polychlorinated biphenyls, and polychlorinated dibenzo-p-dioxins (PCDDs)) in 108 participants from a Columbia University WTC birth cohort. Principal component (PC) analyses were conducted to characterize the mixture of exposure to the three groups of chemicals. We evaluated the associations between geographical exposures (proximity to the WTC disaster) and both chemical exposures (PCs) and stress (demoralization). We then evaluated the effect these exposures (PCs and stress) had on previously reported associations between geographical WTC exposure and birth outcomes (birth weight and birth length) in this study population to understand their individual roles in the observed associations. Geographical exposure via proximity to the WTC was associated with the PC reflecting higher PCDD exposure (PC3) (β = 0.60, 95% CI: 0.03, 1.18 for living/working within 2 miles of the WTC; and β = 0.73, 95% CI = 0.08, 1.38 for living within 2 miles of WTC). Previously reported reductions in birth weight and length associated with WTC proximity (β = −215.2, 95% CI: −416.2, −14.3 and β = −1.47, 95% CI: −2.6, −0.34, respectively) were attenuated and no longer significant for birth weight (β = −156.4, 95% CI: −358.2, 45.4) after adjusting for PC3, suggesting that PCDDs may act as partial mediators in this previously observed association. The results of this study can help focus future research on the long-term health effects of these prenatally exposed populations.

Cancer Incidence in World Trade Center Rescue and Recovery Workers: 14 Years of Follow-Up

BACKGROUND

Statistically significantly increased cancer incidence has been reported from 3 cohorts of World Trade Center (WTC) disaster rescue and recovery workers. We pooled data across these cohorts to address ongoing public concerns regarding cancer risk 14 years after WTC exposure.

METHODS

From a combined deduplicated cohort of 69 102 WTC rescue and recovery workers, a sample of 57 402 workers enrolled before 2009 and followed through 2015 was studied. Invasive cancers diagnosed in 2002-2015 were identified from 13 state cancer registries. Standardized incidence ratios (SIRs) were used to assess cancer incidence. Adjusted hazard ratios (aHRs) were estimated from Cox regression to examine associations between WTC exposures and cancer risk.

RESULTS

Of the 3611 incident cancers identified, 3236 were reported as first-time primary (FP) cancers, with an accumulated 649 724 and 624 620 person-years of follow-up, respectively. Incidence for combined FP cancers was below expectation (SIR = 0.96, 95% confidence interval [CI] = 0.93 to 0.99). Statistically significantly elevated SIRs were observed for melanoma-skin (SIR = 1.43, 95% CI = 1.24 to 1.64), prostate (SIR = 1.19, 95% CI = 1.11 to 1.26), thyroid (SIR = 1.81, 95% CI = 1.57 to 2.09), and tonsil (SIR = 1.40, 95% CI = 1.00 to 1.91) cancer. Those arriving on September 11 had statistically significantly higher aHRs than those arriving after September 17, 2001, for prostate (aHR = 1.61, 95% CI = 1.33 to 1.95) and thyroid (aHR = 1.77, 95% CI = 1.11 to 2.81) cancers, with a statistically significant exposure-response trend for both.

CONCLUSIONS

In the largest cohort of 9/11 rescue and recovery workers ever studied, overall cancer incidence was lower than expected, and intensity of WTC exposure was associated with increased risk for specific cancer sites, demonstrating the value of long-term follow-up studies after environmental disasters.

Cognitive impairment and World Trade Centre-related exposures

On 11 September 2001 the World Trade Center (WTC) in New York was attacked by terrorists, causing the collapse of multiple buildings including the iconic 110-story 'Twin Towers'. Thousands of people died that day from the collapse of the buildings, fires, falling from the buildings, falling debris, or other related accidents. Survivors of the attacks, those who worked in search and rescue during and after the buildings collapsed, and those working in recovery and clean-up operations were exposed to severe psychological stressors. Concurrently, these 'WTC-affected' individuals breathed and ingested a mixture of organic and particulate neurotoxins and pro-inflammogens generated as a result of the attack and building collapse. Twenty years later, researchers have documented neurocognitive and motor dysfunctions that resemble the typical features of neurodegenerative disease in some WTC responders at midlife. Cortical atrophy, which usually manifests later in life, has also been observed in this population. Evidence indicates that neurocognitive symptoms and corresponding brain atrophy are associated with both physical exposures at the WTC and chronic post-traumatic stress disorder, including regularly re-experiencing traumatic memories of the events while awake or during sleep. Despite these findings, little is understood about the long-term effects of these physical and mental exposures on the brain health of WTC-affected individuals, and the potential for neurocognitive disorders. Here, we review the existing evidence concerning neurological outcomes in WTC-affected individuals, with the aim of contextualizing this research for policymakers, researchers and clinicians and educating WTC-affected individuals and their friends and families. We conclude by providing a rationale and recommendations for monitoring the neurological health of WTC-affected individuals.

Temporal Aspects of the Association between Exposure to the World Trade Center Disaster and Risk of Cutaneous Melanoma

Rescue/recovery workers who responded to the World Trade Center (WTC) attacks were exposed to known/suspected carcinogens. Studies have identified a trend toward an elevated risk of cutaneous melanoma in this population; however, few found significant increases. Furthermore, temporal aspects of the association have not been investigated. A total of 44,540 non-Hispanic White workers from the WTC Combined Rescue/Recovery Cohort were studied between March 12, 2002 and December 31, 2015. Cancer data were obtained through linkages with 13 state registries. Poisson regression was used to estimate hazard ratios and 95% confidence intervals using the New York State population as the reference; change points in hazard ratios were estimated using profile likelihood. We observed 247 incident cases of melanoma. No increase in incidence was detected during 2002-2004. From 2005 to 2015, the hazard ratio was 1.34 (95% confidence interval = 1.18-1.52). A dose‒response relationship was observed by arrival time at the WTC site. Risk was elevated just over 3 years after the attacks. Whereas WTC-related exposures to UVR or other agents might have contributed to this result, exposures other than those at the WTC site, enhanced medical surveillance, and lack of a control group with a similar proportion of rescue/recovery workers cannot be discounted. Our results support continued study of this population for melanoma.

Impact of healthcare services on thyroid cancer incidence among World Trade Center-exposed rescue and recovery workers

BACKGROUND

A recent study of World Trade Center (WTC)-exposed firefighters and emergency medical service workers demonstrated that elevated thyroid cancer incidence may be attributable to frequent medical testing, resulting in the identification of asymptomatic tumors. We expand on that study by comparing the incidence of thyroid cancer among three groups: WTC-exposed rescue/recovery workers enrolled in a New York State (NYS) WTC-medical monitoring and treatment program (MMTP); WTC-exposed rescue/recovery workers not enrolled in an MMTP (non-MMTP); and the NYS population.

METHODS

Person-time began on 9/12/2001 or at enrollment in a WTC cohort and ended at death or on 12/31/2015. Cancer data were obtained through linkages with 13 state cancer registries. We used Poisson regression to estimate rate ratios (RRs) and 95% confidence intervals (CIs) for MMTP and non-MMTP participants. NYS rates were used as the reference. To estimate potential changes over time in WTC-associated risk, change points in RRs were estimated using profile likelihood.

RESULTS

The thyroid cancer incidence rate among MMTP participants was more than twice that of NYS population rates (RR = 2.31; 95% CI = 2.00-2.68). Non-MMTP participants had a risk similar to NYS (RR = 0.96; 95% CI = 0.72-1.28). We observed no change points in the follow-up period.

CONCLUSION

Our findings support the hypothesis that no-cost screening (a benefit provided by WTC-MMTPs) is associated with elevated identification of thyroid cancer. Given the high survival rate for thyroid cancer, it is important to weigh the costs and benefits of treatment, as many of these cancers were asymptomatic and may have been detected incidentally.

Stroke hospitalizations, posttraumatic stress disorder, and 9/11-related dust exposure: Results from the World Trade Center Health Registry

BACKGROUND

Few studies have examined the association between disaster-related factors and stroke by subtype or number. We investigated the association between 9/11-related posttraumatic stress disorder (PTSD), dust exposure, and stroke subtype as well as recurrent strokes.

METHODS

The study included 29,012 individuals enrolled in the World Trade Center Health Registry. Stroke cases were obtained by matching Registry enrollees to the New York State Department of Health's discharge records for inpatient visits between 2000 and 2016. Cox proportional hazards regression models were performed to examine the association between 9/11-related risk factors and stroke by subtype. Multinomial logistic regression models were conducted to assess the associations between the same risk factors and the number of stroke hospitalizations.

RESULTS

Having PTSD significantly increased the risk of developing ischemic and hemorrhagic stroke, with adjusted hazards ratios (AHRs) of 1.64 (95% confidence interval [CI]: 1.28-2.10) and 1.73 (95% CI: 1.10-2.71), respectively. The point estimate for dust cloud exposure, although not significant statistically, suggested an increased risk of ischemic stroke (AHR = 1.20, 95% CI: 0.96-1.50). PTSD was significantly associated with recurrent strokes with an adjusted odds ratio of 1.79 (95% CI: 1.09-2.95).

CONCLUSIONS

PTSD is a risk factor for both ischemic and hemorrhagic stroke and is associated with recurrent strokes. Dust exposure on 9/11 is a possible risk factor for ischemic stroke but not for hemorrhagic stroke, and was not associated with recurrent strokes. Our findings warrant additional research on stroke-morbidity and mortality associated with 9/11-related PTSD and dust exposure.

Cancer incidence in World Trade Center-exposed and non-exposed male firefighters, as compared with the US adult male population: 2001-2016

OBJECTIVE

To compare cancer incidence in Fire Department of the City of New York (FDNY) firefighters who worked at the World Trade Center (WTC) site to incidence in a population of non-WTC-exposed firefighters, the Career Firefighter Health Study (CFHS) cohort, and to compare rates from each firefighter cohort to rates in demographically similar US males.

METHODS

FDNY (N=10 786) and CFHS (N=8813) cohorts included male firefighters who were active on 11 September 2001 (9/11) and were followed until death or 31 December 2016. Cases were identified from 15 state cancer registries. Poisson regression models assessed cancers in each group (FDNY and CFHS) versus US males, and associations between group and cancer rates; these models estimated standardised incidence ratios (SIRs) and adjusted relative rates (RRs), respectively. Secondary analyses assessed surveillance bias and smoking history.

RESULTS

We identified 915 cancer cases in 841 FDNY firefighters and 1002 cases in 909 CFHS firefighters. FDNY had: higher rates for all cancers (RR=1.13; 95% CI 1.02 to 1.25), prostate (RR=1.39; 95% CI 1.19 to 1.63) and thyroid cancer (RR=2.53; 95% CI 1.37 to 4.70); younger median ages at diagnosis (55.6 vs 59.4; p<0.001, all cancers); and more cases with localised disease when compared with CFHS. Compared with US males, both firefighter cohorts had elevated SIRs for prostate cancer and melanoma. Control for surveillance bias in FDNY reduced most differences.

CONCLUSIONS

Excess cancers occurred in WTC-exposed firefighters relative to each comparison group, which may partially be explained by heightened surveillance. Two decades post-9/11, clearer understanding of WTC-related risk requires extended follow-up and modelling studies (laboratory or animal based) to identify workplace exposures in all firefighters.

Dose-response relationship between World Trade Center dust exposure and hepatic steatosis

BACKGROUND

The World Trade Center (WTC) attack exposed thousands of workers to toxic chemicals that have been linked to liver diseases and cancers. This study examined the relationship between the intensity of WTC dust exposure and the risk of hepatic steatosis in the WTC General Responders Cohort (GRC).

METHODS

All low-dose computed tomography (CT) scans of the chest performed on the WTC GRC between September 11, 2001 and December 31, 2018, collected as part of the World Trade Center Health Program, were reviewed. WTC dust exposure was categorized into five groups based on WTC arrival time. CT liver density was estimated using an automated algorithm, statistics-based liver density estimation from imaging. The relationship between the intensity of WTC dust exposure and the risk of hepatic steatosis was examined using univariate and multivariable regression analyses.

RESULTS

Of the 1788 WTC responders, 258 (14.4%) had liver attenuation less than 40 Hounsfield units (HU < 40) on their earliest CT. Median time after September 11, 2001 and the earliest available CT was 11.3 years (interquartile range: 8.0-14.9 years). Prevalence of liver attenuation less than 40 HU was 17.0% for arrivals on September 11, 2001, 16.0% for arrivals on (September 12, 2001 or September 13, 2001), 10.9% for arrivals on September 14-30, 2001, and 9.0% for arrivals on January 10, 2001 or later (p = 0.0015). A statistically significant trend of increasing liver steatosis was observed with earlier arrival times (p < 0.0001). WTC arrival time remained a significant independent factor for decreased liver attenuation after controlling for other covariates.

CONCLUSIONS

Early arrival at the WTC site was significantly associated with increasing hepatic steatosis.

Adapting meaning-centered psychotherapy for World Trade Center responders

OBJECTIVE

To date, nearly 10,000 World Trade Center (WTC) responders have been diagnosed with at least one type of WTC-related cancer, and over 70 types of cancer have been related to WTC occupational exposure. Due to the observed latency period for malignancies, the WTC Health Program anticipates increases in rates of new cancer diagnoses. Given the growing number of cancer diagnoses in this population, there is an urgent need to develop a novel intervention to address the psychosocial needs of WTC responders with cancer. Meaning-centered psychotherapy (MCP) is a structured psychotherapeutic intervention originally developed to help patients with advanced cancer find and sustain meaning in life despite illness-related limitations. Existential distress and loss of meaning are critical and understudied elements of psychological health that have been widely overlooked among WTC responders with cancer.

METHOD

We have adapted MCP for WTC responders (MCP-WTC) for the treatment of WTC responders who have been diagnosed with WTC-certified cancers. MCP-WTC aims to target the complex crisis in meaning faced by those responders who responded to the 9/11 attacks and subsequently were diagnosed with cancer as a result of their service.

RESULTS

We describe the adaptation of MCP-WTC and the application of this intervention to meet the unique needs of those exposed to the terrorist attacks of September 11, 2001 (9/11), participated in the rescue, recovery, and clean-up effort at Ground Zero, and were diagnosed with WTC-related cancer. We highlight the novel aspects of this intervention which have been designed to facilitate meaning-making in the context of the patient's response to 9/11 and subsequent diagnosis of cancer.

SIGNIFICANCE OF RESULTS

This work provides a rationale for MCP-WTC and the potential for this intervention to improve the quality of life of WTC responders and help these patients navigate life after 9/11 and cancer.

Mental health mediators of subjective cognitive concerns among World Trade Center responders

Decline in cognitive functioning among rescue and recovery workers who responded in the aftermath of the September 11, 2001, World Trade Center (WTC) attacks is of emerging interest. Responders are vulnerable to cognitive decline from exposure to airborne toxins present at the WTC site, as well as from WTC-related mental and physical health conditions. To better understand the relationship between occupational WTC exposure, mental health, physical health and subjective cognitive functioning, we examined the mediating role of health status in the association between exposure and subjective cognitive concerns in a multi-site, longitudinal investigation of the WTC General Responder cohort (n = 16,380 responders; n = 58,575 visits) for the period 2002-2015. Through latent class analyses, we identified a four-level marker of cognitive concerns based on information from a Self-Administered Mental Health Questionnaire. Using generalized linear mixed models with random intercepts, we observed that a higher intensity WTC exposure composite was associated with greater cognitive concerns, and that this association was operating almost entirely through mental health comorbidities, not physical health comorbidities. In fully adjusted models, the inclusion of probable depression, anxiety, PTSD and use of psychotropic medications attenuated the association between highest WTC exposure and greatest cognitive concerns. Physical health did not appear to be on the pathway between WTC exposure and cognitive concerns. Understanding the underlying sources of cognitive concerns may help identify vulnerable members of the General Responder cohort and potentially aid clinical decision-making, such as treatment choice and enhanced screening options. Earlier diagnosis and symptom treatment may help preserve functional independence.

Hospitalizations among World Trade Center Health Registry Enrollees Who Were under 18 Years of Age on 9/11, 2001-2016

Much of the literature on hospitalizations post-September 11, 2001 (9/11) focuses on adults but little is known about post-9/11 hospitalizations among children. Data for World Trade Center Health Registry enrollees who were under 18-years old on 9/11 were linked to New York State hospitalization data to identify hospitalizations from enrollment (2003–2004) to December 31, 2016. Logistic regression was used to analyze factors associated with hospitalization. Of the 3151 enrollees under age 18 on 9/11, 243 (7.7%) had at least one 9/11-related physical health hospitalization and 279 (8.9%) had at least one 9/11-related mental health hospitalization. Individuals of non-White race, those living in New York City Housing Authority housing, those exposed to the dust cloud on 9/11, and those with probable 9/11-related PTSD symptoms were more likely to be hospitalized for a 9/11-related physical health condition. Older age and having probable 9/11-related PTSD symptoms at baseline were associated with being hospitalized for a 9/11-related mental health condition. Dust cloud exposure on 9/11 and PTSD symptoms were associated with hospitalizations among those exposed to 9/11 as children. Racial minorities and children living in public housing were at greater risk of hospitalization. Continued monitoring of this population and understanding the interplay of socioeconomic factors and disaster exposure will be important to understanding the long-term effects of 9/11.

Breast Cancer Characteristics in the Population of Survivors Participating in the World Trade Center Environmental Health Center Program 2002-2019

The destruction of World Trade Center on 11 September 2001 exposed local community members to a complex mixture of known carcinogens and potentially carcinogenic substances. To date, breast cancer has not been characterized in detail in the WTC-exposed civilian populations. The cancer characteristics of breast cancer patients were derived from the newly developed Pan-Cancer Database at the WTC Environmental Health Center (WTC EHC). We used the Surveillance, Epidemiology, and End Results (SEER) Program breast cancer data as a reference source. Between May 2002 and 31 December 2019, 2840 persons were diagnosed with any type of cancer at the WTC EHC, including 601 patients with a primary breast cancer diagnosis (592 women and 9 men). There was a higher proportion of grade 3 (poorly differentiated) tumors (34%) among the WTC EHC female breast cancers compared to that of the SEER-18 data (25%). Compared to that of the SEER data, female breast cancers in the WTC EHC had a lower proportion of luminal A (88% and 65%, respectively), higher proportion of luminal B (13% and 15%, respectively), and HER-2-enriched (5.5% and 7%, respectively) subtypes. These findings suggest considerable differences in the breast cancer characteristics and distribution of breast cancer intrinsic subtypes in the WTC-exposed civilian population compared to that of the general population. This is important because of the known effect of molecular subtypes on breast cancer prognosis.

Persistent organic pollutants at the synapse: Shared phenotypes and converging mechanisms of developmental neurotoxicity

The developing nervous system is sensitive to environmental and physiological perturbations in part due to its protracted period of prenatal and postnatal development. Epidemiological and experimental studies link developmental exposures to persistent organic pollutants (POPs) including polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, polybrominated diphenyl ethers, and benzo(a)pyrene to increased risk for neurodevelopmental disorders in children. Mechanistic studies reveal that many of the complex cellular processes that occur during sensitive periods of rapid brain development are cellular targets for developmental neurotoxicants. One area of research interest has focused on synapse formation and plasticity, processes that involve the growth and retraction of dendrites and dendritic spines. For each chemical discussed in this review, we summarize the morphological and electrophysiological data that provide evidence that developmental POP exposure produces long-lasting effects on dendritic morphology, spine formation, glutamatergic and GABAergic signaling systems, and synaptic transmission. We also discuss shared intracellular mechanisms, with a focus on calcium and thyroid hormone homeostasis, by which these chemicals act to modify synapses. We conclude our review highlighting research gaps that merit consideration when characterizing synaptic pathology elicited by chemical exposure. These gaps include low-dose and nonmonotonic dose-response effects, the temporal relationship between dendritic growth, spine formation, and synaptic activity, excitation-inhibition balance, hormonal effects, and the need for more studies in females to identify sex differences. By identifying converging pathological mechanisms elicited by POP exposure at the synapse, we can define future research directions that will advance our understanding of these chemicals on synapse structure and function.

Selective hippocampal subfield volume reductions in World Trade Center responders with cognitive impairment

INTRODUCTION

The objective of this study was to investigate associations between dementia in World Trade Center (WTC) responders and in vivo volumetric measures of hippocampal subfield volumes in WTC responders at midlife.

METHODS

A sample of 99 WTC responders was divided into dementia and unimpaired groups. Participants underwent structural T1-weighted magnetic resonance imaging. Volumetric measures included the overall hippocampus and eight subfields. Regression models examined volumetric measure of interest adjusting for confounders including intracranial volume.

RESULTS

Dementia was associated with smaller hippocampal volume and with reductions across hippocampal subfields. Smaller hippocampal subfield volumes were associated with longer cumulative time worked at the WTC. Domain-specific cognitive performance was associated with lower volumetric measures across hippocampal subregions.

CONCLUSIONS

This is the first study to investigate hippocampal subfield volumes in a sample of WTC responders at midlife. Selective hippocampal subfield volume reductions suggested abnormal cognition that were associated with WTC exposure duration.

Lung Cancer Characteristics in the World Trade Center Environmental Health Center

The destruction of the World Trade Center (WTC) towers on 11 September 2001 resulted in acute and chronic dust and fume exposures to community members, including local workers and residents, with well-described aerodigestive adverse health effects. This study aimed to characterize lung cancer in the WTC Environmental Health Center (WTC EHC) focusing on gender and smoking history. WTC EHC patients undergo an initial evaluation that includes WTC exposure information, demographics, and tobacco use. Detailed cancer characteristics are recorded from pathology reports. As of 31 December 2019, 248 WTC EHC patients had a diagnosis of lung cancer. More patients with lung cancer were women (57%) compared to men (43%). Many cases (47% women, 51% men) reported acute dust cloud exposure. Thirty-seven percent of lung cancer cases with available smoking history were never-smokers (≤1 pack-years) and 42% had a ≤5 pack-year history. The median age of cancer diagnosis in never-smoking women was 61 years compared to 66 years in men. Adenocarcinoma was more common in never-smokers compared to ever-smokers (72% vs. 65%) and in women compared to men (70% vs. 65%). We provide an initial description of lung cancers in local community members with documented exposure to the WTC dust and fumes.

The Development of a WTC Environmental Health Center Pan-Cancer Database

(1) Background: Recent studies have reported elevated risks of multiple cancers in the World Trade Center (WTC) affected community members (also called WTC “Survivors”). The large variety of WTC-cancers created a need to develop a comprehensive cancer database. This paper describes the development of a pan-cancer database at the WTC Environmental Health Center (EHC) Data Center. (2) Methods: A new REDCap-based pan-cancer database was created using the pathology reports and available biomarker data of confirmed cancer cases after review by a cancer epidemiologist, a pathologist, physicians and biostatisticians. (3) Results: The WTC EHC pan-cancer database contains cancer characteristics and emerging biomarker information for cancers of individuals enrolled in the WTC EHC and diagnosed after 11 September 2001 and up to 31 December 2019 obtained from WTC EHC clinical records, pathological reports and state cancer registries. As of 31 December 2019, the database included 3440 cancer cases with cancer characteristics and biomarker information. (4) Conclusions: This evolving database represents an important resource for the scientific community facilitating future research about the etiology, heterogeneity, characteristics and outcomes of cancers and comorbid mental health conditions, cancer economics and gene–environment interaction in the unique population of WTC survivors.

Cardiovascular disease in the World Trade Center Health Program General Responder Cohort

BACKGROUND

Over 90,000 rescue and recovery responders to the September 2001 World Trade Center (WTC) attacks were exposed to toxic materials that can impair cardiac function and increase cardiovascular disease (CVD) risk. We examined WTC-related exposures association with annual and cumulative CVD incidence and risk over 17 years in the WTC Health Program (HP) General Responder Cohort (GRC).

METHODS

Post 9/11 first occurrence of CVD was assessed in 37,725 responders from self-reported physician diagnosis of, or current treatment for, coronary artery disease, myocardial infarction, stroke and/or congestive heart failure from WTCHP GRC monitoring visits. Kaplan-Meier estimates of CVD incidence used the generalized Wilcoxon test statistic to account for censored data. Cox proportional hazards regression analyses estimated the CVD hazard ratio associated with 9/11/2001 arrival in responders with and without dust cloud exposure, compared with arrival on or after 9/12/2001. Additional analyses adjusted for comorbidities.

RESULTS

To date, 6.3% reported new CVD. In covariate-adjusted analyses, men's CVD 9/11/2001 arrival risks were 1.40 (95% confidence interval [CI] = 1.26, 1.56) and 1.43 (95% CI = 1.29, 1.58) and women's were 2.16 (95% CI = 1.49, 3.11) and 1.59 (95% CI = 1.11, 2.27) with and without dust cloud exposure, respectively. Protective service employment on 9/11 had higher CVD risk.

CONCLUSIONS

WTCHP GRC members with 9/11/2001 exposures had substantially higher CVD risk than those initiating work afterward, consistent with observations among WTC-exposed New York City firefighters. Women's risk was greater than that of men's. GRC-elevated CVD risk may also be occurring at a younger age than in the general population.

Initial Whole-Genome Sequencing of Plasma Cell Neoplasms in First Responders and Recovery Workers Exposed to the World Trade Center Attack of September 11, 2001

PURPOSE

The World Trade Center (WTC) attack of September 11, 2001 created an unprecedented environmental exposure to known and suspected carcinogens. High incidence of multiple myeloma and precursor conditions has been reported among first responders to the WTC disaster. To expand on our prior screening studies, and to characterize the genomic impact of the exposure to known and potential carcinogens in the WTC debris, we were motivated to perform whole-genome sequencing (WGS) of WTC first responders and recovery workers who developed a plasma cell disorder after the attack.

EXPERIMENTAL DESIGN

We performed WGS of nine CD138-positive bone marrow mononuclear samples from patients who were diagnosed with plasma cell disorders after the WTC disaster.

RESULTS

No significant differences were observed in comparing the post-WTC driver and mutational signature landscapes with 110 previously published WGSs from 56 patients with multiple myeloma and the CoMMpass WGS cohort (n = 752). Leveraging constant activity of the single-base substitution mutational signatures 1 and 5 over time, we estimated that tumor-initiating chromosomal gains were windowed to both pre- and post-WTC exposure.

CONCLUSIONS

Although limitations in sample size preclude any definitive conclusions, our findings suggest that the observed increased incidence of plasma cell neoplasms in this population is due to complex and heterogeneous effects of the WTC exposure that may have initiated or contributed to progression of malignancy.

A Workshop on Cognitive Aging and Impairment in the 9/11-Exposed Population

The terrorist attacks on 11 September 2001 potentially exposed more than 400,000 responders, workers, and residents to psychological and physical stressors, and numerous hazardous pollutants. In 2011, the World Trade Center Health Program (WTCHP) was mandated to monitor and treat persons with 9/11-related adverse health conditions and conduct research on physical and mental health conditions related to the attacks. Emerging evidence suggests that persons exposed to 9/11 may be at increased risk of developing mild cognitive impairment. To investigate further, the WTCHP convened a scientific workshop that examined the natural history of cognitive aging and impairment, biomarkers in the pathway of neurodegenerative diseases, the neuropathological changes associated with hazardous exposures, and the evidence of cognitive decline and impairment in the 9/11-exposed population. Invited participants included scientists actively involved in health-effects research of 9/11-exposed persons and other at-risk populations. Attendees shared relevant research results from their respective programs and discussed several options for enhancements to research and surveillance activities, including the development of a multi-institutional collaborative research network. The goal of this report is to outline the meeting's agenda and provide an overview of the presentation materials and group discussion.

A Behavioral-Analytic Model for Assessing Stress in Firefighters

Research has documented a number of acute and chronic stressors unique to the fire service. Due to the rise in mental health concerns in firefighters, there has been increased awareness of the negative effects of unmanaged stress. The present study employed a behavioral-analytic model to construct a brief screening measure of stress for this population: the Firefighter Assessment of Stress Test (FAST). Psychometric properties of the FAST were evaluated using data from active-duty firefighters throughout the United States. Results indicated the FAST has good internal reliability (α = 0.89), as well as good convergent and discriminant validity. Also, the factor structure of the FAST revealed three significant subscales reflective of stress associated with responding to calls, administrative difficulties, and being overworked. Scoring and interpretation guidelines were established to suggest when further assessment is warranted. The FAST offers a brief and valid method of self-assessment of current stress levels in firefighters. Information obtained from the FAST (i.e., overall stress level and domains) has the potential to facilitate more immediate identification and recognition of stress in firefighters than what has been possible to date. Moreover, heightened awareness of stress and its effects will hopefully culminate in expanded efforts directed toward stress reduction and intervention for firefighters and their families.

Performance of Risk Factor-Based Guidelines and Model-Based Chest CT Lung Cancer Screening in World Trade Center-Exposed Fire Department Rescue/Recovery Workers

BACKGROUND

Lung cancer is a leading cause of cancer incidence and death in the United States. Risk factor-based guidelines and risk model-based strategies are used to identify patients who could benefit from low-dose chest CT (LDCT) screening. Few studies compare guidelines or models within the same cohort. We evaluate lung cancer screening performance of two risk factor-based guidelines (US Preventive Services Task Force 2014 recommendations [USPSTF-2014] and National Comprehensive Cancer Network Group 2 [NCCN-2]) and two risk model-based strategies, Prostate Lung Colorectal and Ovarian Cancer Screening (PLCOm2012) and the Bach model) in the same occupational cohort.

RESEARCH QUESTION

Which risk factor-based guideline or model-based strategy is most accurate in detecting lung cancers in a highly exposed occupational cohort?

STUDY DESIGN AND METHODS

Fire Department of City of New York (FDNY) rescue/recovery workers exposed to the September 11, 2001 attacks underwent LDCT lung cancer screening based on smoking history and age. The USPSTF-2014, NCCN-2, PLCOm2012 model, and Bach model were retrospectively applied to determine how many lung cancers were diagnosed using each approach.

RESULTS

Among the study population (N = 3,953), 930 underwent a baseline scan that met at least one risk factor or model-based LDCT screening strategy; 73% received annual follow-up scans. Among the 3,953, 63 lung cancers were diagnosed, of which 50 were detected by at least one LDCT screening strategy. The NCCN-2 guideline was the most sensitive (79.4%; 50/63). When compared with NCCN-2, stricter age and smoking criteria reduced sensitivity of the other guidelines/models (USPSTF-2014 [44%], PLCOm2012 [51%], and Bach[46%]). The 13 missed lung cancers were mainly attributable to smoking less and quitting longer than guideline/model eligibility criteria. False-positive rates were similar across all four guidelines/models.

INTERPRETATION

In this cohort, our findings support expanding eligibility for LDCT lung cancer screening by lowering smoking history from ≥30 to ≥20 pack-years and age from 55 years to 50 years old. Additional studies are needed to determine its generalizability to other occupational/environmental exposed cohorts.