Polychlorinated naphthalene concentrations and distribution in feed raw materials
Shujun Dong1, Xiaomin Li1, Peilong Wang1
1Institute of Quality Standard and Testing Technology for Agro-Products, The Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Chemosphere
|September 19, 2018
Summary
Polychlorinated naphthalene (PCN) levels were higher in animal-based feed materials than plant-based ones. Lower chlorinated PCNs, particularly Di-CNs, were most prevalent, with significant toxicity contributions from specific congeners.
Area of Science:
- Environmental Chemistry
- Food Safety
- Toxicology
Background:
- Polychlorinated naphthalenes (PCNs) are persistent organic pollutants with potential toxic effects.
- Understanding PCN contamination in animal feed is crucial for food safety and risk assessment.
- Previous studies have focused on other dioxin-like compounds, necessitating PCN-specific investigations in feed.
Purpose of the Study:
- To quantify and characterize 75 polychlorinated naphthalene (PCN) congeners in various animal and plant-origin feed raw materials.
- To compare PCN concentrations and patterns between feed materials of animal and plant origin.
- To assess the toxic contribution of PCNs to the overall dioxin-like compounds in feed.
Main Methods:
- Analysis of 75 polychlorinated naphthalene (PCN) congeners in six animal and three plant feed raw materials collected in China.
- Gas chromatography-mass spectrometry (GC-MS) for congener identification and quantification.
- Calculation of toxicity equivalencies (TEQs) for PCNs and comparison with PCDDs, PCDFs, and PCBs.
Main Results:
- Total PCN concentrations ranged from 147 to 1009 ng kg-1, with fish meal showing the highest levels.
- Animal-origin feed materials (mean: 551 ng kg-1) had higher PCN concentrations than plant-origin materials (mean: 294 ng kg-1).
- Lower chlorinated PCNs, especially Di-CNs (53%), were predominant, with specific congeners like CN5/7 and 24/14 being most abundant. PCNs contributed 2.0%-6.5% to total TEQs.
Conclusions:
- Feed raw materials, particularly those of animal origin, are significant reservoirs of polychlorinated naphthalenes (PCNs).
- The dominance of lower chlorinated PCNs suggests specific sources or degradation pathways in feed production.
- While PCN mass concentrations are high, their TEQ contribution to total dioxin-like compounds is relatively low but warrants attention for comprehensive food safety assessments.
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