Food safety faces added risks from climate change
The European Food Safety Authority (EFSA) is an independent scientific agency of the European Union (EU), established in 2002 to provide scientific advice and risk assessment on food safety to protect consumers. Based in Parma, Italy, EFSA is responsible for assessing and communicating risks associated with the food chain, including food and feed production, processing, and distribution. EFSA evaluates data and conducts research to provide advice to the EU institutions and member states on a range of issues, including food additives, contaminants, genetically modified organisms, and nutrition. Its role is critical in ensuring the safety of the food we eat and promoting public health across the EU. EFSA scientist Angelo Maggiore, a member of EFSA’s unit for Knowledge, Innovation and Partnership Management explains the authority’s response to some of the newer challenges it faces.
The impacts of climate change can already be felt on the fisheries and aquaculture sector in Europe as waters warm, species migrate from their traditional habitats, weather events become more extreme, and alien species spread. In the realm of food safety what are the kinds of challenges that climate change brings and how can they be addressed?
Climate change poses significant challenges to food safety. Long-term changes in temperature, humidity, rainfall patterns and the frequency of extreme weather events can affect for example the occurrence and intensity of certain food-borne diseases, and favour the establishment of invasive alien species harmful to plant and animal health. This was one of the key findings of our project on climate change as a driver of emerging risks for food and feed safety, plant, animal health and nutritional quality (CLEFSA), which looked at over 100 emerging risks.
For the fisheries and aquaculture sector specifically, climate change can affect the occurrence, intensity and toxicity of blooms of potentially toxic marine and freshwater algae and bacteria. Marine biotoxins are among the most likely emerging risks to human health that we will face in the future as a result of climate change.
Other effects of climate change include impacts on toxic compounds such as their transport pathways in the environment, their fate (including bioaccumulation and elimination), their toxicity and our exposure to them. The introduction and spread of new pests and diseases as a result of a changing climate may also affect the use of veterinary drugs (potentially contributing to antibiotic resistance). Heavier and more frequent rainfall increases the risk of sewer overflow into rivers and coastal environments. In addition, more extreme climatic conditions may affect food hygiene in primary production, storage, transport and distribution.
We face diverse challenges as a result. First of all, we must take climate change into consideration when carrying out risk assessments of the food chain. Environmental scanning exercises can boost our preparedness by identifying signals of emerging risks. More generally, applying One Health principles, experts in different disciplines (for example, epidemiology, analytical chemistry, marine veterinary, aquaculture, and toxicology) should collaborate more closely by sharing their knowledge and expertise in their different fields.
Does climate change introduce new threats to seafood safety, or does it “just” increase the risk levels of existing threats? Do new threats call for the development of new systems to reduce the risk to the public? Please provide a couple of examples of new climate-change-associated threats to seafood.
Climate change can do both. It can increase our exposure or susceptibility to known and new hazards. Our CLEFSA project identified a series of potential emerging risks related to marine biotoxins, with ciguatoxins identified as the most likely emerging risk to human health. Ciguatera fish poisoning (CFP) is the most common type of marine biotoxin food poisoning worldwide. It is typically caused by the consumption of fish that have accumulated ciguatoxins (CTX), which are produced by microalgae.
Typical of (sub)tropical areas, CFP was first recorded in the Spanish and Portuguese Macaronesia islands in 2004. EFSA and the Spanish Agency for Food Safety and Nutrition (AESAN) launched funding for the EuroCigua project a few years ago to better understand the risks of CFP in Europe. The initiative aimed at determining the epidemiological characteristics of CFP, analyse the presence of CTX in microalgae and fish, and develop analytical methods to characterise CTXs. A follow-up project is ongoing to collect more data needed to ensure adequate management of risks from CFP.
Cyanobacteria in food is another example. Our scientists looked at our exposure to cyanobacterial populations and their toxicity to help develop predictive models, also considering environmental factors affecting their dominance, persistence and toxicity. Our results suggests that in a future scenario of global warming, we can expect the exposure of humans and farmed animals to cyanotoxins to increase.
Our CLEFSA project emphasised the need for policymakers and other relevant players in the food system to consider increasing surveillance and monitoring to prepare for emerging risks. Climate change considerations can substantially impact the relevance of risk assessment. In addition, we need holistic approaches to deal with multiple stressors (including climate change) in the food and feed safety area.
Ensuring seafood safety calls for a high level of coordination between EFSA and different national and international authorities to ensure action can be rapidly initiated when necessary and the health of consumers safeguarded. Do food safety threats posed by climate change challenge this system of coordination?
Collaboration is one of EFSA’s core values. Climate change is indeed a test case for how scientists can work more closely together. We need more transdisciplinary research and data to be shared among scientists. Closer collaboration is also needed between risk managers, risk assessors and researchers.
To facilitate such exchanges in this area, EFSA has established two knowledge networks, the Emerging risks Exchange Networks (EREN) and the Stakeholder Discussion Group (StaDG-ER).
The EREN was established in 2010 to promote the exchange of information, expertise and the coordination of activities among Member States and observers. The StaDG-ER, also set up in 2010, enables EFSA to capitalise on stakeholders’ specialist knowledge in this area, and to improve the exchange of information and dialogue on emerging risks.
In the context of the CLEFSA project, EFSA has built up an interdisciplinary network, comprised of experts from international intergovernmental organisations and coordinators of large EU projects involved with climate change.
Marine biotoxins from algal blooms, for example, can affect fish and shellfish production and can also have an impact on human health. Is climate change changing the lethality or prevalence of marine biotoxins, or introducing new varieties? How does EFSA keep track of these developments?
Climate change impacts such as rises in temperature, longer stratification periods, flooding of estuarine environments and increases in nutrients in coastal environments could create favourable conditions for the growth of a variety of microalgae and bacteria. This would affect the prevalence of marine biotoxins and could potentially see new varieties introduced. Less is known about the effect on the toxicity of the blooms as this depends on various factors such as the relative abundance of the toxic genotype, production of the most toxic variants or the increase in toxin production rate. In order to keep track of new developments, EFSA uses its EREN and StaDG-ER networks as well as the work of its ten expert Panels.
EFSA has also just launched a foresight study on future challenges for the safety of food and feed coming from our oceans. The objective is to map future uses of the ocean and its resources in the context of global changes, and to identify emerging risks for food and feed safety, and other issues that could be relevant for EFSA. Policy and technological developments related to aquaculture and fishing will play a major role in scoping the assessments.
The widespread presence of microplastics in the marine ecosystem means that fish and shellfish are dietary sources of microplastics for humans. What are the health implications for humans of consuming microplastics? What does EFSA recommend with regard to how much seafood people should consume to limit the consumption of microplastics?
EFSA published a statement in 2016 on the presence of microplastics and nanoplastics in food, in particular in seafood. According to the data available in the literature at that time, the average number of particles found in fish was between 1 and 7, in shrimp, an average of 0.75 particles/gram, and in bivalves the average number of particles was 0.2–4 (median value)/gram. Comparisons of microplastic content need to be undertaken with care due to the different units reported by the different authors (e.g. number of particles/marine organism or number of particles/g wet weight).
The digestive tract of marine organisms seems to contain the largest quantities of microplastics. Gutting before consumption will decrease the exposure compared to eating whole fish. However, this would not apply to shellfish such as crustaceans, bivalve molluscs and certain species of small fish as in those cases the digestive tract is not removed.
A potential concern is that microplastics can absorb contaminants. The main contaminants for which some information was available related to polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) that can accumulate in microplastics. There might also be residues of chemical substances contained in the plastics, such as bisphenol A (BPA) and phthalates. Based on the available studies, only microplastics smaller than 150 µm may cross the gut epithelium and cause systemic exposure. The absorption of these microplastics is expected to be limited (≤ 0.3%), and only the smallest fraction (size < 1.5 µm) may penetrate into organs.
In our statement, we made a conservative estimate of our exposure to microplastics after consumption of a portion of mussels (225 g), resulting in a value of 7 µg of plastics. Considering the highest concentrations of contaminants in the plastics reported, and assuming the complete release of the contaminant from the microplastics, that portion of mussels would have a very small effect on our overall exposure to PCBs (increase < 0.006%) or PAHs (increase < 0.004%).
How does EFSA assess fish feed additives?
Our role is to provide scientific advice to support the authorisation process of feed additives. We carry out an evaluation of each new additive submitted for authorisation, of each new use of an authorised feed additive or on the modification or renewal of an authorised additive. Companies wishing to market an additive in the EU must submit an application and a technical dossier with information on the additive, its conditions of use, control methods and data demonstrating its safety and efficacy. Our expert Panel reviews this information and examines the efficacy and safety of the additive in terms of animal and human health as well as the environment. In parallel, the European Union Reference Laboratory for Feed Additives evaluates the analytical methods used to determine the presence of the additive in feed and its possible residues in food.
The European Commission (EC) decides whether or not to authorise feed additives considering EFSA’s scientific advice as well as other relevant factors, in particular potential benefits for animal health and welfare and for the consumer of fishery/aquaculture products. When an EFSA assessment concludes that the safety of a feed additive has been demonstrated but its efficacy has not, the EC is still in a position to authorise the product but should provide a justification for deviating from EFSA’s assessment.
What are the criteria used to measure the welfare of fish and shellfish? How does EFSA contribute to policies that govern the welfare of farmed fish and shellfish?
In 2009, our experts carried out work on a general approach to fish welfare and to the concept of sentience in fish. We recommended that a range of welfare indicators should be considered when animal welfare is being evaluated. Indicators of fish welfare should be species-specific, validated, reliable, feasible and auditable. The European Commission is currently undertaking a comprehensive evaluation of the EU’s animal welfare legislation and as part of this we are providing new advice that reflects the most up-to-date scientific research and data. We expect a new mandate from the European Commission on this topic in the near future. Any new work we carry out will consider the most recent animal welfare approaches and methodologies, but ultimately the criteria used will depend on the content of any new mandate sent to us.
Animal welfare is an increasingly important part of EFSA’s remit. Our activities in the area of fish welfare are carried out in the wider context of animal health and welfare by our Panel on animal health and welfare (AHAW). The Panel provides independent scientific advice to risk managers on all aspects of animal diseases and animal welfare. Our scientific assessments help risk managers identify methods to reduce unnecessary pain, distress and suffering for animals and to improve welfare wherever possible.