Interactions between environmental pollutants and dietary nutrients: current evidence and implications in epidemiological research

Abstract

Environmental pollutants and nutrients may be present in the same foodstuffs or dietary patterns; share internal mechanisms of transport, metabolism and cellular uptake; or target the same molecular signalling pathways and biological functions. Lipophilic pollutants and nutrients, like dioxins and polyunsaturated fatty acids, may often converge at all aforementioned levels and thus the interactions become more likely. Despite this fact, the topic seems overlooked in mainstream epidemiological research. In this essay, we illustrate different levels of documented interactions between pollutants and nutrients with experimental, interventional and epidemiological evidence, paying special attention to lipophilic chemicals. We first describe common pollutants and nutrients encountered in diets and the internal lipophilic interface such as adipose tissue and serum lipids. Next, we discuss the preventive effects of nutrients against absorption and the toxic effects of pollutants, as well as the pollutant-induced perturbation of nutrient metabolism. Finally, we discuss the implications of nutrient–pollutant interactions in epidemiology, providing some examples of negative confounding, modification effect and statistical interactions reported for different outcomes including fetal growth, diabetes and cancer. The evidence discussed in this essay supports that the health impacts of chemicals have likely been underestimated due to the high risk of residual and coexposure confounding in diseases where interactions between pollutants and nutrients may occur.

Association of Pentachlorophenol with Fetal Risk of Prolonged Bradycardia: A Systematic Review and Meta-Analysis

“…Similarly, in humans, with the deterioration of environmental quality, many environmental pollutants can pass through the way such as respiratory tract, the digestive tract, the skin into pregnant woman's body, and then through the limited tire barrier into fetal body because the fetus is sensitive to the chemical poison effect than adults; in the process of growth and development, if some poisonous substances contact within the womb, it may produce some effects, and adult contact with the substance is not the same as severe damage or even cancer [ 29 , 30 ].…”

“…PCP is an anticompetitive inhibitor of human placental alkaline phosphatase (PLAP). Toxicology tests show that PCP is a strong mitochondrial unconjugation agent that reduces plasma membrane mobility and also has a strong inhibitory effect in the acetylcholinesterase on the cell membrane [ 29 ]. Placental alkaline phosphatase is a metalloglycoprotein located on the membrane of late placental cells; in addition to catalytic function, some substances such as IgG, complement factor B, and cartilage matrix protein are related to fetal growth and development.…”

Exploring the relationship between metal exposure, BDNF, and behavior in adolescent males

“…In addition, some of these apparently protective associations may be explained by dietary and lifestyle confounders. For instance, fish consumption is a potential source of toxic metals as well as beneficial nutrients for brain development (Cano-Sancho and Casas, 2021;. Although fish consumption was controlled for in the present study, residual confounding or dietary misclassification cannot be ruled out.…”

Multi-omics signatures of the human early life exposome

“…Diet is a complex, multidimensional exposure, and studying its contribution to health requires a multipronged approach, for which metabolomics is well positioned (Garcia-Perez et al, 2017; Lau et al, 2018; Posma et al, 2020, Stratakis, Siskos in preparation). Importantly, we illustrate in this study that many anthropogenic chemicals are also delivered in the body through the diet, adding to the complexity of metabolomic profiles in human biospecimens and creating an extensive network of nutrient–pollutant interactions that remains vastly unknown and poorly defined by conventional assessment methods (Cano-Sancho and Casas, 2020).…”