Correction to: Geochemical contamination in the Densu Estuary, Gulf of Guinea, Ghana

Correction to: Environmental Science and Pollution Research

https://doi.org/10.1007/s11356-020-10035-4

The correct equations are presented below:

The enrichment factor is calculated using the formula (Ergin et al. 1991):

$$ \mathrm{EF}=\kern0.5em {\left(\mathrm{X}/\mathrm{Fe}\right)}_{\mathrm{sediment}}/{\left(\mathrm{X}/\mathrm{Fe}\right)}_{\mathrm{Background}\ \mathrm{reference}} $$

Where X/Fe is the ratio of the concentrations of metal X (element) to Fe (normalized metal or element).Contamination factor (CF) is a ratio of the concentration of a metal in sediment to natural abundance (pre-industrial reference value for the same metal):

$$ \mathrm{CF}={\mathrm{C}}_{\mathrm{metal}}/{C}_{background\kern0.17em reference} $$

The pollution load index (PLI) is determined by the formula (Tomlinson et al. 1980):

$$ \mathrm{PLI}=\mathrm{n}\surd \left({\mathrm{CF}}_1\times {\mathrm{CF}}_2\times {\mathrm{CF}}_3\dots ..\times {\mathrm{CF}}_{\mathrm{n}}\ \right). $$

Where,

CF=:

C_metal/C_{background reference}

CF=:

contamination factor, n = number of metals

C_metal=:

metal concentration in the sediments

C_{background reference=}:

background value of each metal

PLI=:

Pollution Load Index