Complex forms may be easily created with additive manufacturing methods, but managing surface roughness remains a difficulty, even for flat surfaces, because surface quality is dependent on numerous parameters. This research investigates the effect of some printing factors on surface roughness in 3D printing methods. The purpose of this study is to quantify the most influential input printing factors on surface roughness in 3D printing processes. Polyacrylic acid thermoplastic was used to print workpieces, and mathematical models were generated using the regression method to analyze the relationship between process parameters and surface roughness. The exponential model fits the experimental data slightly better than the linear model. Only Ra-90 met all surface roughness classification requirements, while surface roughness measurements in the 0 and 45-degree directions did not meet the requirements and cannot be used to describe the surface roughness. The study highlights the importance of considering input printing parameters when optimizing surface roughness in 3D printing processes, providing valuable insights into the impact of process parameters on surface roughness.

The aim of the present study was to determine the most significant heavy metal concentration in hen eggs, in particular to compare the heavy metal concentration in eggs originating from industrial poultry farms versus free-range hens. The sampling process was carried out between October and December 2018, in the Republic of Kosovo. In total, 22 random egg samples were collected, with 54.5 and 45.5 of samples coming from poultry farms and free-range hens, respectively. The measurements of the heavy metals were taken by inductively coupled plasma mass spectrometry (ICP-MS), using a wide range of elements, and only the most important elements were reported, such as Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Hg, and Pb within the range of 0.488.45, 38.77289, 4286.5915383.74, 0.45144.74, 61.68550.59, 1078.0411378.56, 0.2935.42, 0.276.54, and 0.041.41μgkg⁻¹, respectively. This study revealed that the heavy metals in eggs from free-range hens are richer in essential elements such as Mn, Fe, and Zn, while poultry farm eggs contain a higher contribution of Cr, Cd, As, and Pb. However, the daily intake of heavy metals from egg consumption was lower than the WHO-FAO advised provisional daily intake. Therefore, egg consumption does not exceed the safety levels of toxic metals and does not pose any risk to human health.

The aim of this study was to determine naturally occurring radionuclides (40K, 226Ra and 232Th) and the artificial radionuclide 137Cs in various honey samples from Kosovo. This study is of particular importance because it is the first effort to evaluate contamination of honey samples by radioactivity at the country level. The average radioactivity concentrations of 226Ra, 232Th, 137Cs and 40K radionuclides on honey samples were found to be 0.49±0.15, 1.28±0.18, 1.03±0.11 and 20.44±0.69 Bq kg-1, respectively. The activity values of 137Cs found in honey samples were well below the limit value (1000 Bq kg-1) recommended by the ICRP in foodstuffs. Only 20% of honey samples were found to be contaminated with artificial isotopes 137Cs, and activities proved that the Chernobyl radiocaesium presents no risk to public health. Our study confirms that the honeys produced in Kosovo are of good quality and are in line with international standards due to radioactivity concentration. So it is a healthy food for consumption.

This study assessed the annual effective dose from drinking water across different age categories, considering various sources of water. The water samples were collected from different locations, with the samples categorized into public drinking water systems, private wells, and bottled water. In the drinking water samples, no radionuclides other than Ra-226, Th-232, K-40, and H-3 were detected. The average tritium concentration in drinking water was measured at 1.84 Bq L−1, significantly below the permissible safety standards. The study indicated that infants received the highest annual effective dose from drinking water, averaging 0.88 mSv year−1, compared to 0.11 mSv*year−1 for children and 0.08 mSv*year−1 for adults. Among the different water sources, well water from Stublla village showed significantly elevated levels at 0.49 mSv*year−1. The highest contribution to the annual effective dose from the ingestion of drinking water comes from Ra-226, Th-232, and K-40, with average values of 1.72, 0.42, and 0.161 mSv*year−1, respectively. Despite these variations, the average annual effective doses from drinking water for infants, children, and adults were 0.81, 0.098, and 0.076 mSv year−1, respectively. Based on drinking water sources, the Stublla region had the highest yearly effective dosage, with an average value of 0.49 mSv year−1.