# Global marine fish trade networks track international pathways of nutrients and contaminants

## TL;DR

Marine fish trade spreads nutrients and low levels of contaminants globally, especially benefiting small countries' nutrition.

## Contribution

Quantifies how fish trade from the Northeast Atlantic affects global nutrient and contaminant flows, highlighting population-specific impacts.

## Key findings

- Fish imports significantly contribute to EPA + DHA requirements in small-population countries like Lithuania.
- Mercury and dioxin exposure from traded fish remains low, with contributions under 4% of domestic exposure.
- Fish body size changes influence nutrient and contaminant concentrations in traded seafood.

## Abstract

Marine fish trade globalizes nutrients and contaminants. Using trade data, human demographic information, and nutrient and contaminant exposure data, the estimated direct consumption of traded fish from Northeast Atlantic Ocean (NEAO) catches varied among 155 importer countries/regions. The associated trade pathways globalised high amounts of important nutrients including iodine, selenium, and eicosapentaenoic acid and docosahexaenoic acid (EPA + DHA) and contributed greatly to annual domestic EPA + DHA requirements for small-population importers (e.g., Lithuania: 62.8%) but not for high-population importers (e.g., Chinese mainland). Traded amounts of mercury, dioxin, and dioxin-like polychlorinated biphenyls (dl-PCBs) from the NEAO fish were low, and associated pathway contributions to total domestic mercury exposures were <4%. Changes in fish body size affected nutrient and contaminant fillet concentrations and subsequently trade dynamics of nutrients and contaminants. Our study provides valuable insights regarding seafood globalization and marine fish trade that can be used to support adaptive management strategies for contaminants and nutrition-sensitive policies.

Image 1

•International wild fisheries trade globalized nutrients and contaminants.•The Northeast Atlantic fishery generally had high nutrients and low contaminants.•Fish imports improved nutritional security for some small-population countries/regions.•Fish body size fluctuations modulated global trade dynamics of nutrients and contaminants.

International wild fisheries trade globalized nutrients and contaminants.

The Northeast Atlantic fishery generally had high nutrients and low contaminants.

Fish imports improved nutritional security for some small-population countries/regions.

Fish body size fluctuations modulated global trade dynamics of nutrients and contaminants.