Proposing new approaches for the risk characterisation of single chemicals and chemical mixtures: The source related Hazard Quotient (HQS) and Hazard Index (HIS) and the adversity specific Hazard Index (HIA)

Abstract

A hazard quotient (HQ) for a single chemical and the hazard index (HI) for a mixture of chemicals were first described as approaches for risk characterisation by the EPA. HQ is defined as the ratio of exposure to an appropriate reference dose such as the ADI. HI is the sum of the HQs of the chemicals in a mixture. HQ and HI have been used to characterise risk after various exposure scenarios. However, both approaches have a significant limitation in the way they are used. The accurate use of HQ or HI requires estimation of aggregate exposure, that is, exposure to a given chemical(s) from all possible relevant sources. In many studies, risk is assessed assuming exposure from a specific source such as, consumption of water or a specific food item, in which chemical(s) concentration(s) have been measured. In this case the classic HQ/HI approach can result in significant underestimation of risk. For this purpose, we developed an alternative approach, named as Source Related HQ (HQs) where HQ S is the ratio of the exposure from the specific source of interest to the respected reference values. According to our approach the HQ S , before being compared to the reference dose, should be adjusted by a correction factor, in order to simulate aggregated exposure. A correction factor can be calculated based on the permitted exposure contribution from the specific source to the permitted aggregated exposure. Another important limitation specific to the HI approach is the use of chemical specific ADIs that do not correspond to the same critical effect. In this study, we present an analysis based on the individual critical effects, in order to derive the critical effect and an adversity specific Hazard Index (HI A ) and risk characterisation for the whole mixture.

Aluminum exposure from food in the population of Lebanon

“…While this is encouraging, the fact of high Al DDE in Lebanon’s vegetables, sweets and ready meals indicate a need for serious consideration regarding food safety monitoring, and control for soil-based Al contamination. In addition, attention to integrate new approach for risk assessment might be well-thought-out [ 44 , 45 ].…”

Incidence, stability and risk assessment for sulfonamides and tetracyclines in aqua-cultured Nile Tilapia fish of Egypt

“…The acceptable daily intake (ADI, μg/kg bw/day) for SAs and TCs are respectively 3 and 5 (μg/kg bw/day) according to JECFA [ 20 ]. The risk characterization was performed following the new approaches assigned by Goumenou & Tsatsakis [ 21 ] for single chemicals and for chemical mixtures. These new parameters were the source related Hazard Quotient (HQ S ) and Hazard Index (HI S ) and the adversity specific Hazard Index (HI A ).…”

Overview of the effects of chemical mixtures with endocrine disrupting activity in the context of real‑life risk simulation (RLRS): An integrative approach (Review)

“…Acknowledging the infinite possible combination of mixtures, the development of hazard estimation approaches fit for purpose, instead of the "umbrella" approaches to cover all grounds, might be more appropriate in certain cases (62). With a view to alleviate uncertainties, a method outline for defined mixtures is proposed (Fig.…”