Age-stratified probabilistic cancer and noncancer inhalation risks from volatile organic compounds near a major petrochemical complex in Rayong, Thailand

Atmospheric carbonyl compounds in a tropical urban area: Levels, occurrence, and Monte Carlo-based health risk assessment

Carbonyl compounds (CCs) are relevant atmospheric pollutants due to the high toxicity and carcinogenicity of some species. This study assessed the lifetime carcinogenic (LCR) and non-carcinogenic (hazard quotient, HQ; hazard index, HI) risks for three age groups exposed by inhalation, using Monte Carlo simulations based on CCs’ atmospheric levels measured at seven sites in Salvador, Brazil, during the rainy and dry periods. Ten CCs were passively sampled and determined by HPLC-UV. Formaldehyde (FA) and acetaldehyde (AA) predominated, accounting for approximately 55% and 61% of total concentrations in the rainy and dry periods, respectively. Higher molecular weight carbonyls predominated at heavy-duty traffic sites, reflecting Brazil’s vehicular fuel matrix, which favors both direct emissions and secondary photochemical formation of CCs. FA concentrations exceeded the TCEQ long-term exposure limit (3.30 µg m− 3) at all sites and periods, reaching up to 7.4 times this limit during the dry period. At the 95th percentile, LCR values for FA and AA exceeded the USEPA lower acceptable limit (1.0 × 10− 6) for all age groups, and FA (up to 3.49 × 10− 5) exceeded the WHO upper limit (1.0 × 10− 5), especially among adults. Deterministic LCR values fell within the 60th–75th percentile range of the probabilistic distributions, indicating that this conventional method underestimated cancer risks. For acrolein, the HQ (P95) was fourfold above the USEPA limit (HQ ≤ 1) in children, and the cumulative HI (P95) exceeded this limit across all three groups. These results showed that no age group is fully protected, highlighting the need to include FA, AA, and acrolein in Brazilian air quality standards, to implement stricter controls on vehicle emissions, and to establish extensive, continuous atmospheric monitoring.

Probabilistic Risk Assessment and Integrated Statistical Modelling to Identify the Key Factors in Acute and Chronic Arsenic Toxicity Among Schoolchildren for Proactive Toxicity Management

Source-oriented probabilistic risk assessment of polycyclic aromatic hydrocarbons in coal-mining streams: Coupling Monte Carlo simulation, positive matrix factorization, and risk models.

Mineral exploitation and energy consumption contribute to significant environmental pollution, threatening ecological stability and human health, especially in large coal mining areas. To evaluate environmental risks in the Yulin coal mining area, a study was carried out on polycyclic aromatic hydrocarbons (PAHs) in a representative river across different seasons. Multivariate statistical analysis and a positive matrix factorization (PMF) model were employed for source identification and quantitative allocation. To assess ecological-health risks linked to PAH concentrations and source orientation, an integrated methodology was applied, combining Monte Carlo simulation (MCS), PMF, and risk assessment models. Among all PAHs, BaA, BaP, BbF, InP, and DahA exhibited elevated concentrations, surpassing USEPA threshold values at many sampling sites. Seasonal variations were observed, with ∑PAH concentrations averaging 185.11 and 128.22 ng∙L-1 in the dry and wet seasons, respectively. PAHs in Kuye River were primarily influenced by coking/petroleum, coal combustion, traffic emissions, and fuel-wood burning, contributing 37.39%, 34.78%, 14.40%, and 13.44%, respectively, to total concentrations. Ecological risks associated with these source-specific PAHs were classified as moderate, mainly attributed to BaA derived from coal combustion sources. Non-carcinogenic risks for all population groups were within safe limits based on the USEPA hazard quotient threshold. In contrast, under conservative exposure assumptions, the average total carcinogenic risks for all six population groups associated with source-specific PAHs exceeded the USEPA acceptable risk level, with a relatively high probability of risk exceedance. Females aged 2 -15 years showed the highest estimated risks, and dermal exposure was estimated as the primary pathway. In addition, traffic emission sources and BaP were inferred as potential priorities for controlling carcinogenic risks. These results are screening-level estimates based on default parameters and require validation using local data. The findings highlight the importance of probabilistic risk assessment methods based on specific pollution sources and provide a scientific basis for comprehensive PAH risk assessment and prevention strategies in coal mining areas.

Age-dependent health risk assessment and excess lifetime cancer risk from radon in groundwater of northeastern Iraq

Abstract Naturally occurring radon in groundwater represents a significant public health concern due to exposure through both ingestion and inhalation. This study investigated radon concentrations across 30 groundwater samples collected from northeastern Iraq, together with associated physicochemical parameters and radiological risk assessments. Measured radon concentrations spanned from 2.9 to 29.7 Bq L−1, with a mean of 12.5 Bq L−1. Approximately 43.3 % of the sampled sites exceeded the USEPA guideline, whereas all concentrations remained below the WHO and UNSCEAR limits. Radiological health risk indicators, including annual effective dose via ingestion and inhalation pathways and excess lifetime cancer risk, were evaluated across three different age groups. Although the overall total annual effective dose remained beneath the WHO recommended limit of 0.1 mSv y−1, infants recorded higher dose values than both children and adults, with five sampling locations surpassing this threshold specifically for the infant group. Excess lifetime cancer risk estimates across all age categories fell within USEPA acceptable boundaries. Pearson correlation, skewness, kurtosis, and Shapiro-Wilk statistical tests were applied to examine relationships between radon levels and water quality indicators. Findings highlight the need for targeted mitigation interventions, continuous environmental monitoring, and community awareness initiatives to reduce long-term waterborne radon health risks.

Cancer burden and health inequalities attributable to occupational arsenic exposure: A 32-year global, regional, and national observational study with projections to 2036

Occupational arsenic exposure (OEA), mainly through inhalation in workplace settings, is an established carcinogenic hazard associated with lung, skin, and bladder cancers. However, long-term trends and the global cancer burden attributable to OEA remain insufficiently characterized. Data from the Global Burden of Disease Study 2021 were used to analyze the cancer burden attributable to OEA from 1990 to 2021. Indicators included summary exposure values (SEVs), deaths, years lived with disability (YLDs), and disability-adjusted life years (DALYs) at global, regional, and national levels. Estimates were reported with 95% uncertainty intervals (UIs) generated from 1000 Monte Carlo simulations. Age-standardized indicators, Joinpoint regression, inequality analysis, decomposition analysis, and frontier analysis were used to assess spatiotemporal trends, drivers, and disparities. Seven forecasting models were evaluated to predict trends from 2022 to 2036. Between 1990 and 2021, global OEA SEV increased from 0.408% to 0.496% (average annual percentage change [AAPC] = 0.288). Cancer deaths rose from 5.5 to 10.5 thousand, YLD from 1.5 to 3.3 thousand, and DALYs from 169.6 to 298.7 thousand. In contrast, age-standardized death rate (AAPC = −0.300) and DALYs rate (AAPC = −0.531) declined. Men bore higher overall burdens, but women experienced faster increases (AAPC 0.428 vs 0.171). High-socio-demographic index (SDI) countries showed continuous improvement, whereas middle- and low-SDI regions-particularly East, South, and Southeast Asia-experienced substantial increases. In East Asia, the AAPCs for age-standardized SEVs, age-standardized death rates, age-standardized YLDs rates, and DALYs rates were 0.953, 1.067, 1.849, and 0.809, respectively. Inequality analysis indicated stable absolute gaps but reduced relative disparities, with burdens still concentrated in low-SDI countries. Decomposition suggested that population growth was the main driver of global burden increases, and frontier analysis highlighted limited improvement potential in low-SDI regions. Forecasting models indicated that the absolute burden of occupational arsenic exposure will continue to rise over the next 15 years. The cancer burden attributable to OEA is still increasing globally, with persistent prevention gaps and socioeconomic disparities. Focused interventions in low- and middle-SDI countries and rapidly industrializing regions are needed, including strengthened occupational exposure regulations, improved workplace arsenic monitoring, engineering controls, personal protective equipment, and regular health surveillance for workers in high-risk industries, to reduce inequalities and mitigate public health threats.

Characteristics and Carcinogenic Risk of PM2.5-Bound Polycyclic Aromatic Hydrocarbons from Charcoal Barbecue (Moo Kratha) Restaurants in Chiang Mai, Thailand

Barbecue (Moo Kratha) restaurants are prevalent in Chiang Mai City, Thailand. However, their PM2.5-bound polycyclic aromatic hydrocarbon (PAH) emissions, compounded by the region’s severe seasonal smoke haze, remain poorly characterized. This study investigated the chemical composition and carcinogenic risk of PM2.5-bound PAHs in this present environment. Ten PM2.5 samples were collected from ten charcoal Moo Kratha restaurants during peak evening hours in February 2026 (early dry season) using a portable air sampler operated as a fixed-location (area) sampler positioned at the customer dining table (2 L min−1, 180 min) on quartz fiber filters, and the 16 US EPA priority PAHs were analyzed by GC-MS. Carcinogenic risk was assessed using benzo[a]pyrene toxicity equivalent (TEQBaP) concentrations and incremental lifetime cancer risk (ILCR) for adult and child customers (diners) via the inhalation pathway. The mean concentrations of PM2.5 and total PAHs were 87.64 µg m−3 and 132.74 ng m−3, respectively, with carcinogenic PAHs contributing 52.3%; the mean TEQBaP of 15.34 ng m−3 provides an internal index of the carcinogenic potency of the PAH mixture. The mean inhalation ILCR for a frequent diner was 2.82 × 10−5 for adults and 2.12 × 10−5 for children, rising to 6.16 × 10−5 and 4.62 × 10−5, respectively, at the most contaminated site; even an occasional (monthly) diner exceeded the 10−6 negligible threshold. These findings indicate that charcoal Moo Kratha restaurants are distinct, persistent sources of carcinogenic PAHs that place diners within the upper part of the tolerable cancer-risk range; worker exposure is expected to be higher but was not quantified here, underlining the need for ventilation and occupational-health strategies.