A team of marine biologists has detected plastic chemical additives in sardines, anchovies and hake from the Mediterranean Sea, although their levels do not pose a risk to human health. According to the work, led by the Institute for Environmental Diagnosis and Water Studies (IDAEA-CSIC) in collaboration with the Institute of Marine Sciences (ICM-CSIC) and the Spanish Institute of Oceanography (IEO-CSIC), pollution by plasticizers it could be one of the causes of the decline in populations of these species, along with climate change and fishing pressure.
The study, published in the journal Environmental Pollution, has observed the presence in these fish of organophosphate esters, a family of chemical compounds widely used in industry (for plastics, textiles, furniture …), which have toxic effects on the nervous and endocrine systems, and can affect the system reproductive or have carcinogenic effects.
The research includes the analysis of 55 samples corresponding to sardines, anchovies and hake caught in areas of Cabo de Creus, the Ebro Delta, the Gulf of Valencia and the Gulf of Alicante. All but two of the fish showed plasticizer levels of up to 73 nanograms per gram of muscle. “In general, the four areas studied presented similar levels of contamination, without significant differences between them, which indicates a similar use of plasticizers throughout the studied area,” explained the IDAEA-CSIC researcher Ethel Eljarrat, lead author.
However, researchers have observed that sardines are the fish with the highest amount of plasticizers found, followed by anchovies and hake. According to marine biologists, these differences are related to the different acquisition, bioaccumulation and metabolism capacities of each of the species. “The lower levels found in hake, which is a partial predator of sardines and anchovies, suggest that these contaminants do not biomagnify along the food chain, since the levels of contamination do not increase from prey to predator”, according to Eljarrat .
The researcher has emphasized that the risk assessment of these pollutants on human health indicates that the consumption of these fish, in itself, does not pose any threat, although she recalled that human exposure to these pollutants is produced both by the ingestion of food, not just fish, such as by inhaling air indoors and outdoors, or breathing dust.
According to Eljarrat, the sum of all these sources of exposure could pose a certain risk to human health, which is why he recommends minimizing exposure to these plasticizers, reducing pollution in marine ecosystems.
The ICM-CSIC team is studying the decline of the sardine and anchovy populations on the west coast of the Mediterranean Sea and according to the marine biologist Joan Giménez, “there are several hypotheses to explain this trend, the increase in fishing pressure, temperatures warmer water due to climate change or the presence of pollutants such as those analyzed in this study “.