Pollution indices: Geocumulation Index (I-geo)
The level of contamination in sediments is commonly assessed and quantified using the so-called geo-accumulation (Igeo) parameter. This was originally defined by Müller (1969) and is obtained using the formula:
[1]
where Cn denotes the measured value ​​and​​Bn is the geochemical background of the site. The factor 1.5 is applied to control variations inBn values ​​caused by anthropogenic influences. The geo-accumulation index (Igeo) was defined into seven classes (Table 1) by Buccolieri et al. (2006).