Microplastics as contaminants in commercially important seafood species

The ingestion of microplastic fragments, spheres, and fibers by marine mollusks, crustaceans, and fish, including a number of commercially important species, appears to be a widespread and pervasive phenomenon. Evidence is also growing for direct impacts of microplastic ingestion on physiology, reproductive success and survival of exposed marine organisms, and transfer through food webs, although the ecological implications are not yet known. Concerns also remain over the capacity for microplastics to act as vectors for harmful chemical pollutants, including plastic additives and persistent organic pollutants, although their contribution must be evaluated alongside other known sources. The potential for humans, as top predators, to consume microplastics as contaminants in seafood is very real, and its implications for health need to be considered. An urgent need also exists to extend the geographical scope of studies of microplastic contamination in seafood species to currently underrepresented areas, and to finalize and adopt standardized methods and quality-assurance protocols for the isolation, identification, and quantification of microplastic contaminants from biological tissues. Such developments would enable more robust investigation of spatial and temporal trends, thereby contributing further evidence as a sound basis for regulatory controls. Despite the existence of considerable uncertainties and unknowns, there is already a compelling case for urgent actions to identify, control, and, where possible, eliminate key sources of both primary and secondary microplastics before they reach the marine environment.

D. Santillo, K. Miller, P. Johnston, Integrated Environmental Assessment and Management, Volume 13, Number 3, pp. 516–521, May 2017

The article

Occurrence of halogenated flame retardants in commercial seafood species available in European markets

PBDEs (congeners 28, 47, 99, 100, 153, 154, 183, 209), HBCD (α, β, γ), emerging brominated flame retardants (PBEB, HBB and DBDPE), dechloranes (Dec 602, 603, 604, syn- and anti-DP), TBBPA, 2,4,6-TBP and MeO-PBDEs (8 congeners) were analysed in commercial seafood samples from European countries. Levels were similar to literature and above the environmental quality standards (EQS) limit of the Directive 2013/39/EU for PBDEs. Contaminants were found in 90.5% of the seafood samples at n. d.-356 ng/g lw (n. d.-41.1 ng/g ww). DBDPE was not detected and 2,4,6-TBP was detected only in mussels, but at levels comparable to those of PBDEs. Mussel and seabream were the most contaminated species and the Mediterranean Sea (FAO Fishing Area 37) was the most contaminated location. The risk assessment revealed that there was no health risk related to the exposure to brominated flame retardants via seafood consumption. However, a refined risk assessment for BDE-99 is of interest in the future. Moreover, the cooking process concentrated PBDEs and HBB.

Òscar Aznar-Alemany, Laura Trabalón, Silke Jacobs and al., Food and Chemical Toxicology, Volume 104, June 2017, Pages 35–47

The article

The influence of microplastic inclusion in feed on carryover of environmental pollutants from feed to seabass and salmon

Themes :

  1. Safe seafood the consumers can trust: protection in the new Era
  2. Marine toxins in seafood and the environment: developments in detection and prediction
  3. Toxicity and modelling: tools and limitations
  4. Rapid detection tools for seafood safety
  5. Quality assurance of seafood monitoring data
  6. Emerging approaches for future seafood safety
  7. Science slam session*
  8. Others

Granby, Kit; Rasmussen, Rie Romme; Kotterman, Michiel; Sloth, Jens Jørgen; Cederberg, Tommy Licht; Marques, António T. ; Koelmans, Albert; Larsen, Bodil Katrine
Published in: Seafood safety new findings ; innovation challenges – 25-26 January 2017 –  abstract book here

Statistical Survey of Persistent Organic Pollutants: Risk Estimations to Humans and Wildlife through Consumption of Fish from U.S. Rivers

U.S. EPA conducted a national statistical survey of fish tissue contamination at 540 river sites (representing 82 954 river km) in 2008–2009, and analyzed samples for 50 persistent organic pollutants (POPs), including 21 PCB congeners, 8 PBDE congeners, and 21 organochlorine pesticides. The survey results were used to provide national estimates of contamination for these POPs. PCBs were the most abundant, being measured in 93.5% of samples. Summed concentrations of the 21 PCB congeners had a national weighted mean of 32.7 μg/kg and a maximum concentration of 857 μg/kg, and exceeded the human health cancer screening value of 12 μg/kg in 48% of the national sampled population of river km, and in 70% of the urban sampled population. PBDEs (92.0%), chlordane (88.5%) and DDT (98.7%) were also detected frequently, although at lower concentrations. Results were examined by subpopulations of rivers, including urban or nonurban and three defined ecoregions. PCBs, PBDEs, and DDT occur at significantly higher concentrations in fish from urban rivers versus nonurban; however, the distribution varied more among the ecoregions. Wildlife screening values previously published for bird and mammalian species were converted from whole fish to fillet screening values, and used to estimate risk for wildlife through fish consumption.

Angela L. Batt, John B. Wathen, James M. Lazorchak, Anthony R. Olsen, and Thomas M. Kincaid,  Environ. Sci. Technol., Article ASAP, February 23, 2017

Microplastics ingestion by a common tropical freshwater fishing resource

Microplastics pollution is widespread in marine ecosystems and a major threat to biodiversity. Nevertheless, our knowledge of the impacts of microplastics in freshwater environments and biota is still very limited. The interaction of microplastics with freshwater organisms and the risks associated with the human consumption of organisms that ingested microplastics remain major knowledge gaps. In this study, we assessed the ingestion of microplastics by Hoplosternum littorale, a common freshwater fish heavily consumed by humans in semi-arid regions of South America. We assessed the abundance and diversity of both plastic debris and other food items found in the gut of fishes caught by local fishermen. We observed that 83% of the fish had plastic debris inside the gut, the highest frequency reported for a fish species so far. Most of the plastic debris (88.6%) recovered from the guts of fish were microplastics (<5 mm), fibres being the most frequent type (46.6%). We observed that fish consumed more microplastics at the urbanized sections of the river, and that the ingestion of microplastics was negatively correlated with the diversity of other food items in the gut of individual fish. Nevertheless, microplastics ingestion appears to have a limited impact on H. littorale, and the consequences of human consumption of this fish were not assessed. Our results suggest freshwater biota are vulnerable to microplastics pollution and that urbanization is a major factor contributing to the pollution of freshwater environments with microplastics. We suggest the gut content of fish could be used as a tool for the qualitative assessment of microplastics pollution in freshwater ecosystems. Further research is needed to determine the processes responsible for the high incidence of microplastics ingestion by H. littorale, and to evaluate the risk posed to humans by the consumption of freshwater fish that ingested microplastics.

Jacqueline Santos Silva-Cavalcanti, José Diego B. Silva, Elton José de França and al., Environmental Pollution, Volume 221, February 2017, Pages 218–226

The article

Are We Eating Our Fleece Jackets? Microfibers Are Migrating Into Field And Food

This has scientists wondering: Are we eating our sweaters’ synthetic microfibers?

Probably, says Chelsea Rochman, an ecologist and evolutionary biologist at the University of Toronto, St. George. “Microfibers seem to be one of the most common plastic debris items in animals and environmental samples,” Rochman says.

In fact, peer-reviewed studies have shown that these synthetic microfibers — a type of plastic smaller than a millimeter in length and made up of various synthetic polymers — have popped up in table salt in China, in arctic waters and in fish caught off the coast of California. These tiny fibers make up 85 percent of human debris on shorelines across the globe, according to a 2011 study. They’re basically inescapable. So it’s not unlikely they’re finding their way into the human diet, especially in seafood. (…) (npr.org, february 6, 2017)

The news

UK Government to investigate whether microplastics pose risk to human health

Dame Sally Davies, the chief medical officer for England, is to study the risks from eating seafood containing tiny particles of plastic. Experts are concerned that millions of tonnes of tiny debris from plastic bags, bottles and clothes in the world’s oceans could have potentially harmful effects on the body.

Someone eating half a dozen oysters is likely to consume 50 tiny pieces of microplastic, according to a report by the House of Commons Environmental Audit Committee, released earlier this year.

In its response to the report the Government acknowledged that there is “little evidence” on the impact to human health from eating the plastic. (…) (independent.co.uk, 14/11/2016)

The news