Microplastic pollution in snow was investigated in top of the Amanos Mountain in Hatay region, southern Turkey. Snow samples were collected from four stations located in different heights and fronts of the mountain. Abundance of microplastic ranged from 10.5 to 16 MP per liter and a total of 519 microplastic particles (MPs) were identified in snow samples. The majority of identified microplastic were fiber (>99%), black in color and 0.5 – 2.5 mm (62%) size class and polyester (35%). This is the first study examining the microplastic pollution in snow from Turkey. Local wind and trajectory analyses revealed that MPs appeared in the sampling region originated from closely located Amik Plain and/or were transported from remote areas with northwesterly and southerly airflows.

Water-soluble and trace metal species in fine particulate matter (PM_2.5) were determined for indoor and outdoor environments in Doha, Qatar. During the study period, PM_2.5 concentrations showed significant variability across several indoor locations ranging from 7.1 to 75.8 μg m⁻³, while the outdoor mass concentration range was 34.7–154.4 µg m⁻³. The indoor and outdoor PM_2.5 levels did not exhibit statistically significant correlation, suggesting efficient building envelope protection against outdoor PM_2.5 pollution. Rather than outdoor sources, human activities such as cooking, cleaning, and smoking were the most significant influence on chemical composition of indoor PM_2.5. NH₄⁺ concentration was insufficient to neutralize SO₄²⁻ indoors and outdoors, indicating the predominant presence of NH₄HSO₄. The enrichment factors indicated that outdoor Fe, Mn, Co, Cr, and Ni in PM_2.5 mostly originated from crustal sources. In contrast, the remaining outdoor trace metals (Cu, Zn, As, Cd, Pb, and V) were mainly derived from anthropogenic sources. The indoor/outdoor concentration ratios revealed significant indoor sources for NH₄⁺ and Cu. The crustal matter, water-soluble ions, and sea salt explained 42%, 21%, and 1% of the indoor PM_2.5 mass, respectively. The same groups sequentially constituted 41%, 16%, and 1% of the outdoor PM_2.5 mass.

We present data on bioactive trace metal concentrations of suspended particulate matter (SPM) samples from the Exclusive Economic Zone (EEZ) of Qatar as part of a broader study examining the distributions of particulate bioactive metals, biogenic and lithogenic influences, and biogeochemical controls on particulate trace metal concentrations in the Arabian Gulf. The influence of dust deposition and hydrography was also investigated as factors controlling on bioactive metal concentrations. In this study, we analyzed the composition of water column SPM (> 1 µm) along a transect across the Gulf during two seasonal periods: late spring (May) and late summer (September) 2019. Eight bioactive trace metals (Fe, V, Mn, Zn, Co, Cu, Ni and Ba) were measured in SPM using ICP-MS. Our results show that Fe and Zn are enriched in SPM, likely due to aerosol depositions, while Mn, Ni, Cu, Co and Ba exhibited trends corresponding to hydrographic parameters such as density. Fe, Mn, Co, Ba demonstrated negative correlations with oxygen, explaining their depletion at depth and near sediment layer.

Influence of Atmospheric Aerosol Deposition and its Elemental Composition on Marine Productivity in the Central Arabian/Persian Gulf The Arabian Gulf is a shallow, warm oligotrophic, and hypersaline marginal sea of the Indian Ocean. Due to intense evaporation, limited freshwater input, recurrent dust event and harsh environmental conditions, nutrient concentrations and productivity are significantly impacted by the harsh and changing environmental conditions. Atmospheric aerosols can impact surface ocean biology and biogeochemical processes in the Arabian Gulf as a result of the dust events and limited inputs. However, the rates of macro- and micronutrient inputs from the atmosphere to the Arabian Gulf are not well constrained. Both inorganic and organic forms of nitrogen and phosphorus may contribute to productivity in the Arabian/Persian Gulf. Productivity and by proxy precious resources such as fisheries can be closely linked to aerosols nutrient deposition. In this study, we use the Arabian Gulf as a natural laboratory for investigating the temporal variability of atmospheric macro- and micronutrients, the partitioning between organic and inorganic forms of nitrogen and phosphorus, and the role of trace metals in marine productivity. Based on annual time-series aerosol measurements, we provide new insights into atmospheric concentrations of macro- and micronutrients in the central Arabian/Persian Gulf. Additionally, using 1-dimensional biogeochemical model simulations, we investigate the influence of atmospheric aerosol deposition on primary productivity in the Gulf. The results obtained suggest that atmospheric deposition is an important process regulating marine productivity in the Arabian Gulf.