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This study investigates the concentrations, health risks, and potential sources of heavy metal elements and polycyclic aromatic hydrocarbons (PAHs) in PM1.1 particles in Zhuji, a major copper-processing city in China. The ratios of heavy metals (summer: 0.906; winter: 0.619) and PAHs (>0.750 in both seasons) in PM1.1/PM2.0 suggest significant accumulation in ultrafine particles. In winter, heavy metal concentrations in PM1.1 reached up to 448 ng/m3, and PAH concentrations were 13.4 ng/m3—over ten times higher than in summer. Health risk assessments revealed that hazard index (HI) values exceeded 1.00 for five age groups (excluding infants) during winter, indicating chronic exposure risks. Incremental lifetime cancer risk (ILCR) values surpassed the upper acceptable limit (1.0 × 10⁻⁴) for four age groups, with Cr, As, Cd, and Pb as major contributors. PAH-related ILCRs were also elevated in winter, with benzo[a]pyrene (BaP) identified as the most potent carcinogen. Enrichment factor (EF) and principal component analysis (PCA) indicated that industrial activities and traffic emissions were the dominant anthropogenic sources of heavy metals. Diagnostic ratio analysis further showed that PAHs mainly originated from vehicle and coal combustion. These findings provide critical insights into pollution patterns in industrial cities and underscore the importance of targeted mitigation strategies.

The transition from the Hafit to the Umm an-Nar period on the Oman peninsula in the third millennium BC is regarded as a period of substantial social and economic change. Although many thousands of tombs from the Hafit period remain, other archaeological evidence, such as settlements, is scarce. In 2015 therefore, a new archaeological research project conducted by the University of Tübingen and funded by the German Research Foundation was launched at al-Khashbah to investigate its Hafit and Umm an-Nar period remains. During the first two seasons research consisted of an intensive field survey, aerial survey, two geophysical surveys, as well as archaeological excavations in selected areas within the site. Among other archaeological remains, al-Khashbah features three Hafit-period stone towers and six towers from the Umm an-Nar period, including the famous rectangular building. The most important discoveries are a Hafit-period settlement with monumental mud-brick architecture and a stone-built tower dating to the end of the fourth millennium BC, associated with the oldest evidence of copper processing in Oman. Both findings testify to the importance of al-Khashbah for the investigation of the development of complexity at the end of the fourth and the beginning of the third millennium BC.