Introduction: Lead (Pb) contamination in drinking water poses serious public health risks, particularly when concentrations exceed the WHO permissible exposure limit (PEL) of 0.01 mg/L (10 ppb). This study investigates Pb levels in drinking water sources across five districts Kohat, Hangu, Dera Ismail Khan (D.I. Khan), Bannu, and Karak to assess contamination severity, spatial distribution, and potential health risks.Methods: Drinking water samples were collected from multiple locations within the five districts and analyzed for Pb concentrations. Statistical analyses, including one-way ANOVA and the Shapiro-Wilk normality test, were conducted to evaluate variations and data distribution. Health risk assessment was performed using estimated daily intake (EDI) and hazard quotient (HQ) calculations. Additionally, geospatial analysis using Inverse Distance Weighting (IDW) modeling was employed to identify contamination hotspots.Results: All districts exceeded the WHO PEL for Pb, with the highest mean concentrations recorded in Bannu (0.720 mg/L) and Karak (0.693 mg/L). Maximum Pb levels reached 1.809 mg/L in Bannu and 1.572 mg/L in Karak. Exceedance rates were 100% in Hangu, Bannu, and Karak. ANOVA analysis (p-value = 8.16 × 10⁻¹¹) indicated significant variations among districts, while the Shapiro-Wilk test (W = 0.742, p-value < 0.0001) confirmed non-normal data distribution. Health risk assessment revealed critical risks, particularly for children, with HQ values exceeding safe thresholds, notably in Bannu and Karak. Geospatial modeling identified contamination hotspots, including Jozara Water (Hangu), Mufti Mehmood Circuit House (D.I. Khan), and Kalanger (Bannu).Discussion and conclusion: The findings highlight widespread Pb contamination in drinking water across the study area, posing severe health risks. Immediate intervention through advanced water treatment, stringent regulatory enforcement, and continuous monitoring is essential to safeguard public health.

Radon (Rn) is a radioactive, odorless, and colorless gas which has a half-life of 3.83 days. One of the main sources of Rn which is directly consumed by the population is Groundwater (Tube well, Bo...

Background: External quality frameworks such as ISO 9001 certification lay the foundation for healthcare quality, patient safety, and operational efficiency, but sustained improvement depends on leadership, a culture of safety, and systems that translate assurance into ongoing learning. Evidence on this transition from low- and middle-income countries, particularly in specialized cardiac care, remains limited. Methods: A retrospective longitudinal analysis of quality assurance data from January 2020 to December 2025 was conducted at the Peshawar Institute of Cardiology (PIC-MTI), Pakistan. Independent-samples t-tests, one-way ANOVA, and Difference-in-Differences (DiD) modeling were applied, with three regional hospitals of similar bed capacity and patient volume serving as a comparison group. Results: Following ISO 9001 certification (February 2022), monthly mortality within 48 h declined from 2.8% (SD ± 0.4%) to 1.9% (SD ± 0.3%) (t = 3.21, df = 58, P = .004). Hospital-acquired infections (HAIs) fell from 3.2% to 2.0% (t = 4.15, P = .002), reaching 1.3% by 2025, with zero CLABSIs recorded in the final quarter following the mid-period intensification of the infection-control bundle. Mean length of stay decreased from 6.2 to 4.7 days [ANOVA: F(2,57) = 8.76, P < .001]. Patient satisfaction rose from 78% to above 90%. DiD modeling found a net 30% reduction in HAIs and 20% reduction in length of stay (LOS) associated with the certification process relative to the comparison trajectory. Conclusions: ISO 9001 certification, undertaken alongside deliberate investment in leadership, a culture of safety, and structured use of data, is associated with sustained improvements in clinical outcomes and operational efficiency at a resource-limited cardiac care center that has not yet pursued formal Joint Commission International (JCI) accreditation but is using JCI’s standards, as one example of an internationally recognized framework, to guide its preparation. The pattern observed here suggests that a learning quality management system, and not any single certificate or accreditation status, is what converts external standards into measurable gains, offering a replicable model for institutions considering how to move from quality assurance toward continual quality improvement.