Increased toxicity due to migration?

December 22, 2015

A seaweed from Asia - used for human nutrition - contains toxic compounds providing protection against animal consumers. However, newly introduced populations of the alga in North America and Europe contain considerably more of the deterrents. This was recently published by an international team of scientists led by GEOMAR Helmholtz Centre for Ocean Research Kiel. A migration of resistant strains back into Asia in the future is well possible and poses a risk for food safety, as cases of human intoxication may increase in frequency.

Newly introduced marine organisms need to survive in habitats to which they are not adapted. Sometimes they are lucky and the new environment contains only few enemies. Under such conditions introduced species may become invasive, spreading rapidly and causing damage. Some examples are the Chinese mitten crab, the naval ship worm or the Japanese oyster that all invaded North Sea and Baltic Sea areas successfully after they were introduced by humans. However, in some newly reached environments more enemies may be looming. Under such conditions the invader needs to increase its defensive capacity rapidly in order to survive. This has happened in the seaweed Gracilaria vermiculophylla that originates from East Asia and has recently spread into Europe and North America.

In Asia the alga is used for alimentation and preferentially eaten raw, although it occasionally causes severe or even lethal cases of intoxication, due to its content of Prostaglandin, a hormone-like compound. Prostaglandin provides protection against animal consumers, as periwinkles and crustaceans are also very sensitive to it. Newly introduced populations of Gracilaria vermiculophylla in Europe and North America seemingly need to protect themselves more against consumers, for they contain much more Prostaglandin than native populations in Asia. This was demonstrated by a study led by GEOMAR Helmholtz Centre for Ocean Research Kiel, recently published in the international science journal Harmful Algae.

"We have compared 12 selected populations of the alga in East Asia, Mexico and Europe" explains Dr. Florian Weinberger, project leader and co-author of this international study. „That was a difficult task because we used living specimens that had to be collected from all populations and to be transported alive to the cultivation facility of GEOMAR. Only in this way we could compare the capacity of all the specimens to produce deterrents under identical environmental conditions", Weinberger says.

The results of this effort were remarkable. „Non-native populations clearly contained more Prostaglandin than populations from Asia - the concentration was elevated by up to 390 %", explains Mareike Hammann, the main author of this study, which was a part of her PhD project. „After translocation to the new environments Gracilaria vermiculophylla obviously needed to be better protected against consumers, so that individuals containing more Prostaglandin were selected", Hammann continues.

These findings lead to quite new questions: What will happen in case that invasive specimens of Gracilaria vermiculophylla migrate back to Asia one day? „Intoxication of humans by the seaweed could certainly become more frequent" reckons Florian Weinberger. "Permanent screenings of all populations that are used for alimentation may be inevitable from now on, in order to allow for timely warnings in cases of increasing toxicity".

Helmholtz Centre for Ocean Research Kiel (GEOMAR)

Related Consumers Articles from Brightsurf:

When consumers trust AI recommendations--or resist them
The key factor in deciding how to incorporate AI recommenders is whether consumers are focused on the functional and practical aspects of a product (its utilitarian value) or on the experiential and sensory aspects of a product (its hedonic value).

Do consumers enjoy events more when commenting on them?
Generating content increases people's enjoyment of positive experiences.

Why consumers think pretty food is healthier
People tend to think that pretty-looking food is healthier (e.g., more nutrients, less fat) and more natural (e.g., purer, less processed) than ugly-looking versions of the same food.

How consumers responded to COVID-19
The coronavirus pandemic has been a catalyst for laying out the different threats that consumers face, and that consumers must prepare themselves for a constantly shifting landscape moving forward.

Is less more? How consumers view sustainability claims
Communicating a product's reduced negative attribute might have unintended consequences if consumers approach it with the wrong mindset.

In the sharing economy, consumers see themselves as helpers
Whether you use a taxi or a rideshare app like Uber, you're still going to get a driver who will take you to your destination.

Helping consumers in a crisis
A new study shows that the central bank tool known as quantitative easing helped consumers substantially during the last big economic downturn -- a finding with clear relevance for today's pandemic-hit economy.

'Locally grown' broccoli looks, tastes better to consumers
In tests, consumers in upstate New York were willing to pay more for broccoli grown in New York when they knew where it came from, Cornell University researchers found.

Should patients be considered consumers?
No, and doing so can undermine efforts to promote patient-centered health care, write three Hastings Center scholars in the March issue of Health Affairs.

Consumers choose smartphones mostly because of their appearance
The more attractive the image and design of the telephone, the stronger the emotional relationship that consumers are going to have with the product, which is a clear influence on their purchasing decision.

Read More: Consumers News and Consumers Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to