Dysregulation of Cytokine Response in Canadian First Nations Communities: Is There an Association with Persistent Organic Pollutant Levels?

Pascal Imbeault,Sunita Pandey,Jules M Blais,Eva M Krümmel,Michael A Robidoux,Jason A Tetro,Rasha Maal-Bared,François Haman,C Scott Findlay,Tim Seabert,Lionel G Filion,Angelo Tremblay,Susan Springthorpe,Shinjini Pal,Syed A Sattar,Hugo Ten Cate

doi:10.1371/journal.pone.0039931

Pascal Imbeault, Sunita Pandey + Show 14 more

Open Access

https://doi.org/10.1371/journal.pone.0039931

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Journal: PloS one	Publication Date: Jul 2, 2012
Citations: 29	License type: CC BY 4.0

Affiliation: University of Ottawa, Ottawa Hospital, Université Laval

Abstract

In vitro and animal studies report that some persistent organic pollutants (POPs) trigger the secretion of proinflammatory cytokines. Whether POP exposure is associated with a dysregulation of cytokine response remains to be investigated in humans. We studied the strength of association between plasma POP levels and circulating cytokines as immune activation markers. Plasma levels of fourteen POPs and thirteen cytokines were measured in 39 Caucasians from a comparator sample in Québec City (Canada) and 72 First Nations individuals from two northern communities of Ontario (Canada). Caucasians showed significantly higher levels of organochlorine insecticides (β-HCH, p,p′-DDE and HCB) compared to First Nations. Conversely, First Nations showed higher levels of Mirex, Aroclor 1260, PCB 153, PCB 170, PCB 180 and PCB 187 compared to Caucasians. While there was no difference in cytokine levels of IL-4, IL-6, IL-10 and IL-22 between groups, First Nations had significantly greater average levels of IFNγ, IL-1β, IL-2, IL-5, IL-8, IL-12p70, IL-17A, TNFα and TNFβ levels compared to Caucasians. Among candidate predictor variables (age, body mass index, insulin resistance and POP levels), high levels of PCBs were the only predictor accounting for a small but significant effect of observed variance (∼7%) in cytokine levels. Overall, a weak but significant association is detected between persistent organochlorine pollutant exposure and elevated cytokine levels. This finding augments the already existing information that environmental pollution is related to inflammation, a common feature of several metabolic disorders that are known to be especially prevalent in Canada's remote First Nations communities.

Highlights

Persistent organic pollutants (POPs) are a wide range of compounds that include dioxins, polychlorinated biphenyls, organochlorine pesticides and perfluorinated acids
The aim of this study was to determine the strength of association between plasma levels of persistent organic pollutants (POPs) and a specific component of the immune system, as defined by circulating cytokines, in humans
Levels of organochlorine insecticides are,1.2 to 13 times higher in Caucasians compared to First Nations individuals

Summary

Introduction

Persistent organic pollutants (POPs) are a wide range of compounds that include dioxins, polychlorinated biphenyls, organochlorine pesticides and perfluorinated acids. These partially volatile compounds, largely of industrial origin, can be transported large distances from their source via global distillation [1]. Owing to both persistence and lipophilicity, POPs have comparatively high bioaccumulative potential [2]. Global legislation [3] has led to a decline in human exposure to most legacy POPs over the last three decades, even in remote communities [4]. Many individuals living in these regions, including First Nations and Inuit communities, show elevated POP exposure, as suggested by their higher levels of POPs in blood [9] and adipose tissues [10] as compared to individuals living in a southern region of Canada

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