Formal E-waste facilities as a source of mercury to air and soil in Türkiye

Spatio-temporal variations of mercury concentrations in air and soil were measured near 20 formal e-waste recycling facilities and 8 background locations in 8 provinces in Türkiye between June 2021 and May 2022. Annual average Gaseous Elemental Mercury (GEM) concentrations in air at the studied formal e-waste facilities averaged 34 ng/m³ (range from 2.2 to 273 ng/m³), exceeding by more than an order of magnitude average levels of 2.2 ng/m³ (range from 1.6 to 2.6 ng/m³) at background sites. Total mercury concentration (THg) concentration in soils near formal e-waste processing facilities of 0.88 mg/kg dw (range from 0.17 and 12 mg/kg dw) similarly exceeded levels of 0.053 mg/kg dw (range from 0.01 to 0.11 mg/kg dw) in background soils. No clear seasonality in air or soil mercury concentrations were observed, possibly due to variations in the magnitude of recycling operations and in the type of consumer products being recycled in different seasons. Indices such as Enhancement Factor (EF) and Geoaccumulation Index (I_geo) used to define pollution degree/classification in studied areas. EF and I_geo values showed that 25 % and 5 % of air and soil samples taken near formal e-waste facilities, respectively, are very strongly polluted (EF and I_geo are > 3). Based on the overall mean I_geo index, 33.75 % of these soil samples are moderately to extremely contaminated (I_geo is greater than 1). Formal e-waste recycling facilities in Türkiye clearly are a source of mercury to the surrounding environment.