We reviewed how heat exposure is defined using thresholds and reference temperatures derived from the temperature–mortality exposure–response curve in time-series and case-crossover studies using distributed lag non-linear models and propose a harmonisation framework relevant to climate change research and heat disaster preparedness. The rapid review identified variation across studies in heat thresholds and reference temperatures, affecting the comparability of estimates. A case study in Spain illustrates how the minimum mortality temperature (MMT) approach estimates overall heat-related mortality and its contributions from moderate and extreme heat, whereas the percentile-based approach estimates excessive heat mortality that could potentially be prevented by protective measures operating above the heat threshold. Differences in heat thresholds and reference temperatures make findings harder to compare across studies and complicate risk communication. Explicit reporting of these two components and their relevance to the research question and intended application would improve interpretation and translation to public health action.
Extreme heat is increasingly threatening the health of workers worldwide and disproportionately impacting workers in low- and middle-income countries (LMICs). This mapping review was conducted to characterize the existing literature and to identify key gaps in field assessments of heat stress impacts on workers in LMICs. A total of 210 reports were included in the analysis. Almost two-thirds of included articles reported on studies conducted in lower-middle income countries (65
Ozone, a photochemically generated air pollutant, continues to pose a major concern for public health in the United States, with some 125 million people living in areas that exceed national ambient air quality standards set by the United States Environmental Protection Agency. To fully understand the potential impacts of ambient ozone exposure on respiratory health, we conducted a systematic review of United States epidemiologic and experimental studies published from 1980 to 2026, encompassing both acute and chronic exposure windows. This review focused on three key domains: (1) pulmonary function, (2) asthma-related symptoms and emergency department visits/hospitalizations, and (3) other respiratory-related morbidity and mortality. Findings across diverse study designs demonstrated adverse respiratory effects, with children, older adults, and individuals with pre-existing respiratory conditions being disproportionately affected. This review is among the first to comprehensively synthesize ozone-related respiratory health outcomes including pulmonary functions outcomes across both experimental and population-based observational studies—highlighting consistent decrements in lung function, even at concentrations below current regulatory standards. Additionally, this work incorporated ozone-associated school absenteeism, a sensitive yet underexamined indicator for pediatric respiratory health outcome. The observed associations across multiple outcomes and exposure durations underscored the importance of strengthening ambient air quality standards and prioritizing interventions toward high-risk populations. Continued increases in ambient ozone exposure even in the presence of regulatory action and increasing contributions from sources related to climate change such as wildfires emphasize the importance of sustained research and public health planning to safeguard respiratory health in vulnerable communities.
Pharmaceutical pollution has emerged as a critical threat to environmental integrity and public health globally, with India occupying a uniquely prominent position as both the world’s leading generic drug manufacturer and a major hotspot of active pharmaceutical ingredient (API) contamination. This review synthesizes current evidence on the distribution, magnitude, and health consequences of pharmaceutical pollution across India’s principal manufacturing clusters and river systems, with particular emphasis on antimicrobial resistance (AMR) as a downstream public health consequence. Evidence environmental monitoring data, regulatory documentation, and case studies from Patancheru–Hyderabad (Telangana) and Baddi–Barotiwala–Nalagarh (Himachal Pradesh), we highlight evidence demonstrating that active pharmaceutical ingredients (APIs) in pharmaceutical manufacturing hotspots frequently occur at concentrations far exceeding recommended environmental thresholds, while also documenting the occurrence of hazardous heavy metals and organic solvents in affected environments. We further assess the regulatory landscape, including the Environment (Protection) Act (1986), Biomedical Waste Management Rules (2016), Zero Liquid Discharge mandates, and recent CPCB draft guidelines (2025), and identify persistent structural gaps in monitoring, enforcement, and compound-specific discharge standards. The review concludes with evidence-based recommendations for strengthening surveillance frameworks, integrating ecological risk quotient approaches, and aligning Indian policy with emerging international standards. Addressing pharmaceutical pollution is not merely an environmental imperative but an essential component of the global effort to contain AMR, protect vulnerable populations, and achieve health sustainability in low- and middle-income countries.
Low-cost particulate matter (PM) sensors make it possible to measure air pollution in homes, workplaces, and communities that are poorly represented by regulatory networks. Their readings, however, are sensitive to humidity, aerosol composition, concentration range, unit-to-unit variation, and aging. This review examines laboratory and field calibration evidence across environmental and occupational settings, emphasizing transferability and the consequences of calibration error for exposure assessment and health inference. The review identified 66 peer-reviewed studies published from 2015 to 2025, including 32 laboratory evaluations and 34 field studies. The median reported calibrated coefficient of determination (R²) was 0.92 (n = 31) for laboratory studies and 0.72 (n = 29) for field studies; the corresponding median root mean square errors (RMSEs) were 2.6 µg/m³ (n = 7) and 12.3 µg/m³ (n = 9). These values summarize a heterogeneous literature rather than a common pooled effect. Studies differed in aerosol mixture, comparison instrument, concentration range, averaging interval, and validation design. Relative humidity and temperature were considered in most studies. Machine-learning and hybrid models appeared more often in field work and sometimes lowered error, although independent validation across time, place, and sensor units was uneven. Calibration is not a universal correction that can be applied once and carried unchanged into any deployment. Laboratory testing is well suited to defining response limits, particle-size sensitivity, and unit variability. Field co-location is needed to determine how the same device behaves under the sources, weather, concentrations, and time scales relevant to a health study. Credible use in epidemiology or public-health decision-making also requires independent validation, planned checks for drift, and clear reporting of calibration uncertainty.
