International Frameworks Dealing with Human Risk Assessment of Combined Exposure to Multiple Chemicals

Abstract

The development of harmonised terminology and frameworks for the human risk assessment of combined exposure to multiple chemicals ("chemical mixtures") is an important area for EFSA and a number of activities have already been undertaken, i.e. in the fields of pesticides and contaminants. The first step prior to a risk assessment of combined exposure to multiple chemicals is problem formulation defining the relevant exposure, hazard and population to be considered. In practice, risk assessment of multiple chemicals is conducted using a tiered approach for exposure assessment, hazard assessment and risk characterisation. Higher tiers require increasing knowledge about the group of chemicals under assessment and the tiers can range from tier 0 (default values, data poor situation) to tier 3 (full probabilistic models). This scientific report reviews the terminology, methodologies and frameworks developed by national and international agencies for the human risk assessment of combined exposure to multiple chemicals and provides recommendations for future activities at EFSA in this area. SUMMARYHuman risk assessment of combined exposure to multiple chemicals (chemical mixtures) poses several challenges to scientists, risk assessors and risk managers, particularly the complexity of the terminology and problem formulation, the diversity of chemical entities, and the toxicological profiles and exposure patterns in test species and humans. This scientific report aims to describe the terminology and methodologies, review frameworks developed by national and international agencies and discuss future activities at EFSA in this area.

Overview on the Mycotoxins Incidence in Serbia in the Period 2004–2016

“…The original data on combined toxic effects of mycotoxins are limited and therefore the health risk from this multi-exposure is not well-known [97]. Risk assessment of combined exposure to multiple chemicals is defined as a priority objective by European Food Safety Authority (EFSA) and EU [98]. Among the 116 reported possible mycotoxins combinations found by the different authors in cereals and derived cereal product samples, AFs + FUMs, DON + ZEN, AFs + OTA and FUMs + ZEN were the most present ones [99].…”

Food Security: Microbiological and Chemical Risks

“…Data from monitoring systems focused on pesticides and other chemicals in food will in the future also be used for risk assessment of combined exposure to multiple chemicals ("chemical mixtures"). Typically, risk assessment of multiple chemicals is conducted using a tiered approach for exposure assessment, hazard assessment and risk characterization [18], an approach that clearly needs update as new data from animal experiments show the potential for additive effect of such chemicals [19].…”

A pragmatic approach for human risk assessment of chemical mixtures

“…Experiments have shown that chemicals, when exerting similar effects, typically act in a dose-additive manner, and far less frequently in synergistic or antagonistic ways [3,4]. This means that the efficacies of chemicals in a mixture can be added together, as long as the potency of the individual chemicals is appropriately accounted for.…”