Microplastics in the gastrointestinal tracts of fish and the water from an urban prairie creek

Abstract

Microplastics are defined as any plastic with a diameter ≤5 mm. Problems associated with these plastics such as contamination of both marine and freshwater environments and ingestion by aquatic organisms are of increasing concern. Our study quantifies the number of microplastics in a prairie creek immediately downstream of Regina, Saskatchewan, Canada. Water samples and five species of fish were collected from sample sites upstream and downstream of a wastewater treatment plant (WWTP) in the summers of 2015 and 2016. Samples were digested in either a Fe(II)/H 2 O 2 or NaClO solution and observed under a microscope where plastics present were enumerated by colour and type. At least one microplastic was detected in 73.5% of fish and 95.6% of water samples, showing that the creek does, in fact, contain microplastics. Concentrations were higher in water from upstream sites, likely due to dilution of creek water by the release of treated effluent. The results of this study provide baseline conditions for the presence of plastics in the creek prior to a major upgrade of the WWTP scheduled for completion in 2016.

Microplastic prevalence in two fish species in two U.S. reservoirs

“…Agricultural watersheds have previously been associated with high prevalence of microplastics in fishes (Campbell et al 2017;McNeish et al 2018) and agricultural soils have the potential to be a source of microplastics (Nizzetto et al 2016). WWTPs are thought to be key contributors to MP contamination in freshwater systems.…”

“…Thus, our results suggest that the source of microplastics may be associated with agricultural activities, which dominate these watersheds. Agricultural watersheds have previously been associated with high prevalence of microplastics in fishes (Campbell et al 2017;McNeish et al 2018) and agricultural soils have the potential to be a source of microplastics (Nizzetto et al 2016). Additionally, automotive tire wear, and atmospheric deposition may be nonpoint sources of microplastics (Gray et al 2018).…”

Microplastic occurrence and effects in commercially harvested North American finfish and shellfish: Current knowledge and future directions

“…The limited number of studies conducted in North America (e.g., British Columbia, Newfoundland, and Saskatchewan in Canada; California, Connecticut, and Texas in the U.S.) indicate the presence of microplastics in fieldcollected finfish from freshwater bodies, coastal environments, and associated watersheds (e.g., Phillips Liboiron et al (2018) document the presence of microplastics in field-collected commercial finfish, and Rochman et al (2015) reported the presence of anthropogenic debris in eight species of commercial finfish purchased from local markets being sold for human consumption (Table 1). This suggests that microplastic ingestion may be largely influenced by the areas surrounding the sampling location, indicated by the higher incidence of plastics in fishes from more urbanized areas (Phillips and Bonner 2015;Liboiron et al 2016;Campbell et al 2017). This suggests that microplastic ingestion may be largely influenced by the areas surrounding the sampling location, indicated by the higher incidence of plastics in fishes from more urbanized areas (Phillips and Bonner 2015;Liboiron et al 2016;Campbell et al 2017).…”

“…3, Table 1). The reported ingestion of microplastics varies widely for finfish sampled from North American waters, ranging from 0% in individual silver hake (Merluccius bilinearis) to 46.5% in individual pinfish (Lagodon rhomboides) to 83% in individual northern pike (Esox lucius; Campbell et al 2017;Peters et al 2017;Liboiron et al 2018). The reported ingestion of microplastics varies widely for finfish sampled from North American waters, ranging from 0% in individual silver hake (Merluccius bilinearis) to 46.5% in individual pinfish (Lagodon rhomboides) to 83% in individual northern pike (Esox lucius; Campbell et al 2017;Peters et al 2017;Liboiron et al 2018).…”

“…The reported ingestion of microplastics varies widely for finfish sampled from North American waters, ranging from 0% in individual silver hake (Merluccius bilinearis) to 46.5% in individual pinfish (Lagodon rhomboides) to 83% in individual northern pike (Esox lucius; Campbell et al 2017;Peters et al 2017;Liboiron et al 2018). This suggests that microplastic ingestion may be largely influenced by the areas surrounding the sampling location, indicated by the higher incidence of plastics in fishes from more urbanized areas (Phillips and Bonner 2015;Liboiron et al 2016;Campbell et al 2017). For example, Hipfner et al (2018) documented the presence of microfibers in 21% of individual Pacific herring (Clupea pallasii) from the highly urbanized Salish Sea; but no microfibers were detected in herring collected from remote locations along the British Columbia coast.…”