Proposed scheme for the assessment of human health risk from combined exposure to multiple chemicals based on currently available methodologies and options. HBGV: Health-Based Guidance Value, RQ = Risk Quotient, RQi: Risk Quotient for individual mixture components, mRQ: mitigated Risk Quotient, RQSum: Risk Quotient for the mixture, n = number of mixture components, i = a mixture component, HI: Hazard Index, RPI: Reference Point Index, mRPI: modified Reference Point Index, MOET: Margin Of Exposure Total (combined), HBM-GVspecific: Human BioMonitoring—Guidance Value for specific population group, MAF: Mixture Allocation Factor, RQSUM(MAF): Risk Quotient for the mixture adjusted using MAF. α: [111]; β: [112]; γ: [36]; δ: [37]; ε: [113], ζ: [114]; η: [115]; θ: [116].