(16) Salt Preservation of Fish Reduces Heavy Metal Content in Tissues

The ability to detect the presence of elements such as iron, arsenic, and mercury in fish tissues is of vital interest to human consumers and aquaculture. To avoid adverse human health outcomes such as mercury poisoning,... [ view full abstract ]

The ability to detect the presence of elements such as iron, arsenic, and mercury in fish tissues is of vital interest to human consumers and aquaculture. To avoid adverse human health outcomes such as mercury poisoning, effective field methods for screening and quantifying levels of toxic elements in fish tissues must be developed. In addition to detection, preservation methods might affect the concentrations of heavy metals in fish. Salting has been an effective, trusted food preservation method for centuries. Our research suggests that salting not only preserves fish, but also effectively reduces the concentration of certain elements including mercury, iron, and arsenic. The goal of this research is to examine the effects of salting on the presence and concentration of toxic elements in fish tissue samples, and to develop methods for preparing fish tissues for XRF analysis. All tissues were homogenized, weighed, and pressed into individual pellets in preparation for XRF analysis. XRF spectroscopy data revealed that salted fish tissue samples had markedly lower concentrations of all elements known to be present in unsalted tissues, suggesting that salting may in fact reduce toxicity for human consumers. In addition to positive implications for human health, the ability to screen for and quantify the concentration of certain elements can be used to draw conclusions about the overall health of fish populations, as well as the aquatic environments they live in. This research attests to the usefulness of salt as a food safety asset, but also cautions against its use in experimental scenarios when performing risk assessments for aquatic environments and species.