Biomagnification of persistent organic pollutants (POPs) in detritivorous, phytophagous, and predatory invertebrates: How POPs enter terrestrial food web?

Invertebrates are primary contributors to fluxes of nutrients, energy, and contaminants in terrestrial food webs, but the trophodynamic of contaminants in invertebrate food chains is not fully understood. In this study, occurrence and biomagnification of persistent organic pollutants (POPs) were assessed in detritivorous, phytophagous, and predatory invertebrate food chains. Detritivorous species (earthworm and dung beetle) have higher concentrations of POPs than other species. Different composition patterns and biomagnification factors (BMFs) of POPs were observed for invertebrate species. Negative correlations were found between BMFs and log KOW of POPs for detritivorous and most phytophagous species. In contrast, parabolic relationships between BMFs and log KOW were observed in snails and predatory species, possibly attributed to the efficient digestion and absorption of diet and POPs for them. Bioenergetic characteristics are indicative of the biomagnification potential of POPs in terrestrial wildlife, as suggested by the significant and positive correlation between basal metabolic rates (BMRs) and BMFs of BDE 153 for invertebrates, amphibians, reptiles, birds, and mammals. The estimations of dietary exposure suggest that the terrestrial predators, especially feeding on the underground invertebrates, could be exposed to high level POPs from invertebrates.

Concentrations and biomagnification of persistent organic pollutants in three granivorous food chains from an abandoned e-waste recycling site.

The distinct accumulation patterns of persistent organic pollutants (POPs) among granivorous groups and the biomagnification of POPs from crops to granivorous species are still unclear. In this study, occurrence and biomagnification of POPs in three granivorous species including spotted dove (Spilopelia chinensis), scaly-breasted munia (Lonchura punctulata), and reed vole (Microtus fortis Buechner) from a former e-waste recycling site were investigated. Concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in granivorous species ranged from 41.5 to 1370 and 21.1 to 3890 ng/g lipid weight, respectively. PCBs and PBDEs were the main POPs in birds and vole, while decabromodiphenyl ethane (DBDPE) and PBDEs were predominant POPs in crops. The dominance of BDE 209 was observed in samples, with few exceptions. Biomagnification factors (BMFs) of POPs in birds and vole were measured. BMFs of most POPs in vole were higher than those in birds, indicating that POPs had greater biomagnification potential in vole. Species-specific biomagnification of POPs might be affected by many factors, such as physiochemical properties and metabolic capability of POPs. There was significant correlation between concentration ratios of POPs in muscle/air and log KOA, which demonstrated that respiratory elimination to air affects biomagnification of POPs in granivorous birds and vole.