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

Trace and Major Element Concentrations in Cadaveric Lung Tissues from World Trade Center Health Registry Decedents and Community Controls

Studies of the health impacts of the 11 September 2001 terrorist attacks on New York City's (NYC's) World Trade Center (WTC) towers have been hindered by imprecise estimates of exposure. We sought to identify potential biomarkers of WTC exposure by measuring trace and major metal concentrations in lung tissues from WTC-exposed individuals and less exposed community controls. We also investigated associations of lung tissue metal concentrations with self-reported exposure and respiratory symptoms. The primary analyses contrasted post-mortem lung tissue concentrations obtained from autopsies in 2007-2011 of 76 WTC Health Registry (WTCHR) enrollees with those of 55 community controls. Community controls were frequency-matched to WTCHR decedents by age at death, calendar quarter of death, gender, race, ethnicity and education and resided at death in NYC zip codes less impacted by WTC dust and fumes. We found WTCHR decedents to have significantly higher iron (Fe) lung tissue concentrations than community controls. Secondary analyses among WTCHR decedents adjusted for sex and age showed the log(molybdenum (Mo)) concentration to be significantly associated with non-rescue/recovery exposure. Post hoc analyses suggested that individuals whose death certificates listed usual occupation or industry as the Sanitation or Police Departments had elevated lung tissue Fe concentrations. Among WTCHR decedents, exposure to the WTC dust cloud was significantly associated with elevated lung tissue concentrations of titanium (Ti), chromium (Cr) and cadmium (Cd) in non-parametric univariable analyses but not in multivariable analyses adjusted for age and smoking status. Logistic regression adjusted for age and smoking status among WTCHR decedents showed one or more respiratory symptoms to be positively associated with log (arsenic (As)), log(manganese (Mn)) and log(cobalt (Co)) concentrations, while new-onset wheezing and sinus problems were negatively associated with log(Fe) concentration. Fe concentrations among individuals with wheezing, nonetheless, exceeded those in community controls. In conclusion, these data suggest that further research may be warranted to explore the utility as biomarkers of WTC exposure of Fe in particular and, to a lesser extent, Mo, Ti, Cr and Cd in digestions of lung tissue.

Analysis of factors affecting nonalcoholic fatty liver disease in Chinese steel workers and risk assessment studies

BACKGROUND

The global incidence of nonalcoholic fatty liver disease (NAFLD) is rapidly escalating, positioning it as a principal public health challenge with significant implications for population well-being. Given its status as a cornerstone of China's economic structure, the steel industry employs a substantial workforce, consequently bringing associated health issues under increasing scrutiny. Establishing a risk assessment model for NAFLD within steelworkers aids in disease risk stratification among this demographic, thereby facilitating early intervention measures to protect the health of this significant populace.

METHODS

Use of cross-sectional studies. A total of 3328 steelworkers who underwent occupational health evaluations between January and September 2017 were included in this study. Hepatic steatosis was uniformly diagnosed via abdominal ultrasound. Influential factors were pinpointed using chi-square (χ2) tests and unconditional logistic regression analysis, with model inclusion variables identified by pertinent literature. Assessment models encompassing logistic regression, random forest, and XGBoost were constructed, and their effectiveness was juxtaposed in terms of accuracy, area under the curve (AUC), and F1 score. Subsequently, a scoring system for NAFLD risk was established, premised on the optimal model.

RESULTS

The findings indicated that sex, overweight, obesity, hyperuricemia, dyslipidemia, occupational dust exposure, and ALT serve as risk factors for NAFLD in steelworkers, with corresponding odds ratios (OR, 95% confidence interval (CI)) of 0.672 (0.487-0.928), 4.971 (3.981-6.207), 16.887 (12.99-21.953), 2.124 (1.77-2.548), 2.315 (1.63-3.288), 1.254 (1.014-1.551), and 3.629 (2.705-4.869), respectively. The sensitivity of the three models was reported as 0.607, 0.680 and 0.564, respectively, while the precision was 0.708, 0.643, and 0.701, respectively. The AUC measurements were 0.839, 0.839, and 0.832, and the Brier scores were 0.150, 0.153, and 0.155, respectively. The F1 score results were 0.654, 0.661, and 0.625, with log loss measures at 0.460, 0.661, and 0.564, respectively. R2 values were reported as 0.789, 0.771, and 0.778, respectively. Performance was comparable across all three models, with no significant differences observed. The NAFLD risk score system exhibited exceptional risk detection capabilities with an established cutoff value of 86.

CONCLUSIONS

The study identified sex, BMI, dyslipidemia, hyperuricemia, occupational dust exposure, and ALT as significant risk factors for NAFLD among steelworkers. The traditional logistic regression model proved equally effective as the random forest and XGBoost models in assessing NAFLD risk. The optimal cutoff value for risk assessment was determined to be 86. This study provides clinicians with a visually accessible risk stratification approach to gauge the propensity for NAFLD in steelworkers, thereby aiding early identification and intervention among those at risk.

Novel insights into impacts of the "7.20" extreme rainstorm event on water supply security of Henan Province, China: Levels and health risks of tap water disinfection by-products

Spatial distributions, levels, and comprehensive assessments of post-flood tap water disinfection by-products (DBPs) were first studied in Henan Province after the "7.20" Extreme Rainstorm Event in 2021. DBPs levels and health risks in tap water were higher in areas flooded (waterlogged) by storm or upstream flood discharge (WA) and rainstorm-affected areas (RA) compared with other areas (OA), suggesting that extreme rainstorm and flooding events may somehow exacerbate DBPs contamination of tap water through disinfection. WA sites were characterized as contamination hotspots. The results revealed high haloacetic acids (HAAs) levels in WA (Avg: 57.79 μg·L^-1) and RA (Avg: 32.63 μg·L^-1) sites. Compared with normal period, DBPs-caused cancer risk increased by 3 times, exceeding the negligible risk level. Cancer risk came primarily from the ingestion of trihalomethanes (THMs) (>80%), children were the sensitive group. Those between 30 and 69 showed approximately 1.7 times higher disability-adjusted life yearsper person-yearthan other age groups. Apart from regulated DBPs, bromochloracetic acid (BCAA) and dibromoacetonitrile (DBAN) appear to be the main toxicity contributors in these samples. Our results provide a scientific basis for preventing and controlling health risks from tap water DBPs and for assessing the social benefits and burdens of emergency disinfection.

The World Trade Center Health Program: Twenty years of health effects research

It has been 20 years since the devastating terrorist attacks on September 11, 2001. Thousands were injured or killed during the attacks and many more are at risk of adverse health stemming from physical, psychological, and emotional stressors born out of the attacks. Private, federal, state, and local resources were gathered soon after the attacks to address impacts to the community, including the health and well-being of both responders and survivors. Many of these efforts are now largely consolidated under the federally mandated World Trade Center (WTC) Health Program. This program provides medical monitoring and treatment of qualifying conditions among the 9/11-exposed population and supports related physical and mental health research. In this commentary, we describe the WTC Health Program, with emphasis on the health-effects research it has funded since inception in 2011. We describe sentinel research publications, and how science has impacted the program. We provide examples relating studies in this special issue to important roles in the WTC Health Program research agenda. Finally, we provide a perspective on future research needs.