Modeling PCB transfer into hen eggs: Influence of physiological characteristics of the animal

Abstract

Laying hens are likely to be exposed to a wide range of persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs). To improve the safety of poultry farming systems in terms of POPs, the present research focused on assessing the impact of physiological characteristics of the hen on the transfer of ingested PCBs to eggs. Modeling was used as a research tool to explore the impact of some physiological characteristics on the transfer of PCBs in the laying hen. The mathematical model simulates the dynamics of the size of the lipid compartments in the animal and the frequency of laying, with the PCB concentrations in egg yolk and adipose tissue being model outputs. Simulations were run to assess effects of animal characteristics on the transfer of PCBs to eggs. Laying rate proportionally influenced the PCB level of eggs and adipose tissue at steady state. Body fat diluted absorbed PCBs in the absence of laying and significantly influenced the decontamination rate of tissues during depuration after an exposure period. Application of the present model to actual exposure cases highlights its value in improving the support of risk management in livestock farming.

Unraveling Congener-Specific Transfer of Non-Dioxin-Like Polychlorinated Biphenyls (ndl-PCBs) from Feed into Chicken Meat

“…At this point we clearly state that we assume that the ndl-PCB concentration is in equilibrium between muscle fat and other types of body fat. This assumption is supported by other studies and has been used before in modeling of chickens . The critical exploration of this assumption is an interesting subject for future studies.…”

“…This assumption is supported by other studies 16 and has been used before in modeling of chickens. 17 The critical exploration of this assumption is an interesting subject for future studies.…”

Polychlorinated Biphenyl (PCB) Decontamination Kinetics in Lactating Goats (Capra hircus) Following a Contaminated Corn Silage Exposure

“…The time required to obtain uncontaminated milk that is in accordance with the regulation values depends on the speed of decontamination, that is, the half-life of the compounds in the organism. Indeed, the half-life is a function depending on the molecules’ characteristics and the physiological status of the animals, such as level of lactation, turnover of fat due to this lactation and fatness . Previous studies have shown that the PCB depuration kinetics in plasma follows a biphasic kinetic, , resulting in two successive half-lives.…”

Toxicokinetic Modeling of the Transfer of Non-Dioxin-like Polychlorinated Biphenyls (ndl-PCBs) from Feed and Soil into Laying Hens and Their Eggs

“…This assumption is supported by other studies 14 and has been used before in modeling of chickens. 9,15 Due to the fact that the available datasets (Table 1) contain too few measurements of ndl-PCB concentrations in livers of laying hens, 13,16 the basis of the model for fattening chickens 9 is reduced to two compartments (Figure 1 and eqs 1−7): central compartment, which represents blood, and peripheral compartment, which represents total body fat excluding the brain. The values of physiological constants as well as a description of other model variables are presented in Table S1.…”