UV Treatment of Fishmeal:  A Method To Remove Dioxins?

Abstract

This study evaluates the use of UV on contaminated fishmeal and photodegradation of dioxins. Fishmeal samples were placed under UVA or UVB light for 2, 5, and 10 days. Subsequently, analysis of amino acid content, lipid oxidation marker, ethoxyquin content, dioxin, and polychlorinated biphenyl (PCB) profiling was carried out. Exposure of fishmeal for 5 days to UVB light resulted in the degradation of approximately 70% of the dioxin content, while UVA had little effect, only resulting in the degradation of 10% of the dioxin content. UVB did not affect the protein and amino acid content of fishmeal; however, lipid oxidation was triggered. Addition of ethoxyquin prevented oxidation but simultaneously slowed dioxin breakdown. Increasing UVB intensity resulted in a more efficient dioxin degradation of 90%. Exposure of fishmeal to UVB also resulted in an increase in PCBs. UVB light is shown to photodegrade dioxin in fishmeal, indicating the needs to further investigation of methods for application at industrial scale.

Reduction of Persistent Organic Pollutants in Fishmeal: A Feasibility Study

“…Only limited effect was observed on improved fat separation after protease treatment of the fishmeal (30%) and on polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) and DL-PCB degradation by oxidoreductases (10-15%) (30). Exposure of fishmeal to UVB light has been shown to reduce the PCDD/F content by 70% (31). However, the photodegradation mechanism is probably coupled to lipid oxidation with non-and mono-ortho PCBs as reaction products (31).…”

“…Exposure of fishmeal to UVB light has been shown to reduce the PCDD/F content by 70% (31). However, the photodegradation mechanism is probably coupled to lipid oxidation with non-and mono-ortho PCBs as reaction products (31). The industrial use of the principle is questionable due to the need for a long exposure time (5 days) and increased lipid oxidation and DL-PCB content in the fishmeal after the UV treatment.…”

Ultrasound-assisted soil washing processes using organic solvents for the remediation of PCBs-contaminated soils

“…They have revealed an increase in the toxic equivalency concentration induced by the dechlorination of PCBs with 5 – 7 chlorine atoms. The concentrations of PCBs (#105, #118, #123, #158, #157, #167, and #189) with more chlorines and lower toxic equivalency factor (TEF) values decreased, while the concentration of PCBs (#77, #81, #126, and #169) with less chlorine and higher TEF value increased after 5 days of UV irradiation [60] . In this study, no dioxin-like PCBs were detected in the photolytic process using Aroclor 1260.…”

Optimization of an oil leaching process to reduce the level of dioxins and dioxin‐like PCBs in fishmeal

“…The latter technology will also remove most of the fat content in the fishmeal and give a product with altered chemical composition and physical properties. Other relevant or targeted studies reported in the literature include improved fat separation, organic solvent extraction, degradation by oxidoreductases, and UV treatment . However, these technologies have either limited effect or are not or difficult to implement in industrial‐scale production.…”

“…Other relevant or targeted studies reported in the literature include improved fat separation, 9,22 -25 organic solvent extraction, 24 degradation by oxidoreductases, 24 and UV treatment. 26 However, these technologies have either limited effect or are not or difficult to implement in industrial-scale production.…”