Ultrafine industrial aerosol as an occupational risk factor for sintering industry workers

Aim. Assessment of the physicochemical characteristics of suspended particulate matter of the ultrafine range present in the air of the working area of the sintering factory of a metallurgical plant. Materials and methods. The assessment and analysis of the physicochemical parameters of ultrafine particles were carried out in different areas of the sintering factory of the metallurgical plant. The parameters were measured using a portable scanning spectrometer Nanoscan 3910 (USA). The chemical composition of the suspended particulate matter was determined by the method of optical emission spectrometry with inductively coupled plasma (OES-IZP) using the device “Ortima 2100 DV” (PerkinElmer, USA). Results. It was estimated that the concentration of suspended particulate matter of ultrafine size in the main part of the sintering machine ranged from 3.02 × 104 to 3.12 × 104 per cm3, in the tail part of the sintering machine – from 5.09 × 104 to 7.59 × 104 per cm3, in the sintering machine control room No. 1 – from 2.06 × 104 to 2.38 × 104 per cm3, in the workers of the control group – from 1.43 × 104 to 1.73 × 104 per cm3. The quantitative concentration of suspended particulate matter by individual sizes at all workplaces of the sinter plant workers compared to workers of the control group had a significant difference. Values of the total surface area and surface volume of suspended particulate matter of the nano-sized range had their maximum in the tail part and near the head of the sintering machine, the lowest values were recorded around the control room and among the employees of the plant management department. The highest mass concentration of ultrafine particles was recorded in the tail part of the sintering machine (22.55 μg/m3 to 508.35 μg/m3), which is associated with a significant amount of suspended particulate matter of a larger size (≥115.5 nm). The chemical composition of the particles of the ultrafine range included aluminum, calcium, iron, magnesium, manganese, silicon, and phosphorus, which is explained by the specifics of the technological process, and the exceeding of the hygienic standard was observed for calcium, silicon and phosphorus. Conclusions. It was established that during the sintering of the agglomerate in the agglomeration compartment, many suspended particles of the ultrafine range are formed. They included aluminum, iron, manganese, magnesium, silicon, phosphorus, and calcium. Significantly higher values of the number, mass concentration, surface area and surface volume of suspended particulate matter were determined at the workplaces of sintering factory workers, which had a statistically significant difference compared to the workers of the control group.