The prediction of a higher parasite infection as a consequence of an impaired immune system with increasing persistent organic pollution (POP) and heavy metal levels were investigated in adult glaucous gull (Larus hyperboreus) from Svalbard. The levels of chlorinated pesticides, polychlorinated biphenyls (PCBs), toxaphenes and polybrominated diphenyl ethers (PBDEs) were measured in liver. Cupper, cadmium, lead, mercury, selenium and zinc were measured in kidney samples. An elevated ratio of PCB-118 was found, suggesting that local contamination from the settlement was detectable in the glaucous gull. Eight cestodes, four nematodes, two acanthocephalan and three trematode helminth species were found in the intestine. A positive correlation was found between cestode intensities and selenium levels and between acanthocephalan intensities and mercury levels. No correlation was found between parasite intensities and POP concentrations. It is concluded that the contaminant levels found in glaucous gulls do not cause immune suppression severe enough to affect parasite intensity. Consistent relationships between contaminant level and parasite intensity, as an immunotoxic endpoint unit, were not found in the present study.

Hydatid disease is a helminth infection with various clinical complications caused by the larval stage of the dog tapeworm Echinococcus granulosus. The scolicidal agents have been broadly applied for inactivation of the fertile cysts up to now, but these scolicidal agents have several side effects on patients. Therefore, this study aimed to explore the scolicidal activity of green synthesized gold nanoparticles (AuNPs) utilizing mycelia-free culture filtrate of Penicillium aculeatum against hydatid cyst protoscolices of E. granulosus. The size and morphology of AuNPs were affirmed by UV–visible spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and dynamic light scattering (DLS) analysis. The Fourier transform infrared (FT-IR) analysis of AuNPs showed the presence of possible functional groups responsible for the bioreduction and capping. The AuNPs were formed relatively uniform with spherical shape and superior monodispersity with the average diameter of 60 nm. Consequently, various concentrations (0.05, 0.1, 0.2, and 0.3 mg/mL) of green synthesized AuNPs and different exposure times (10, 30, 60, and 120 min) were used against hydatid cyst protoscolices. Statistically, the difference between the scolicidal effects of AuNPs were seen extremely significant for all four concentrations and at various exposure times in comparison to the control group (P < 0.0001). The most mean protoscolex elimination ratio was 94% (0.3 mg/mL AuNPs and 120-min exposure time). The current investigation indicated that applying biogenic AuNPs may be considered as a potential scolicidal agent for cystic hydatid disease. However, further studies are required to evaluate the efficacy of AuNPs in vivo.