Evaluation grading standards of the comprehensive contamination index.

Table 2: Evaluation grading standards of the comprehensive contamination index.

Index	Quality status of crops
ɪ_com< 2	Uncontaminated corn, cassava and plantain
1 < ɪ_com ≤ 2	Lightly contaminated corn, cassava and plantain
2 < ɪ_com ≤ 3	Medium contaminated corn, cassava and plantain
ɪ_com > 3	Severely contaminated corn, cassava and plantain

Adapted from Dong, et al. [23].