[en] The environmental behaviour of short-chain chlorinated paraffins (SCCPs) was investigated in both aquatic and terrestrial ecosystems in the Arctic. The mean concentrations of SCCPs in the aquatic and terrestrial samples were 178.9 ng/g dry weight (dw) and 157.2 ng/g dw, respectively. Short carbon chain (C₁₀) and less-chlorinated (Cl₆) congener groups were predominant in the Arctic samples, accounting for 48.6% and 34.8% of the total SCCPs, respectively. The enrichment of lighter SCCP congener groups (i.e., fewer chlorine atoms with shorter carbon chain lengths) indicated that the fractionation process occurred during long-range transport. The biomagnification factor (BMF) was 0.46 from gammarid to cod, which indicated that the SCCPs did not biomagnify between these two species. The soil–vegetation bioaccumulation factor (BAF) of SCCPs was 29.9, and C₁₃ and Cl_7,8 congener groups tended to accumulate in the terrestrial vegetation. Regression analysis (BAFs = 10.9 × #C + 5.6 × #Cl − 125.2, R = 0.53, P < 0.01) showed that the number of carbon and chlorine atoms influenced the bioaccumulative behaviour of SCCPs and suggested that the number of carbon atoms had a greater influence on the BAFs of SCCPs in the terrestrial ecosystem than did the number of chlorine atoms. - Highlights: • Environmental behaviour of SCCPs was investigated in both aquatic and terrestrial ecosystems in the Arctic. • No biomagnification of SCCPs was found between cod and gammarid species. • SCCPs were bio-accumulated in vegetation samples in the terrestrial ecosystems. • The number of carbon atoms had a greater influence on the BAFs of SCCPs in terrestrial species than that of the number of chlorine atoms.