Antibiotic drug residues are crucial to ensure food safety and minimize risk to human health. Herein, a sensitive high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method was developed and validated for the determination of antibiotic residues (mainly amphenicols) consisting of chloramphenicol (CAP), thiamphenicol (TAP), florfenicol (FF), and florfenicol amine (FFA) in aquatic products. Amphenicols were well separated on a Kinetex F5 (100 mm × 3.0 mm, 2.6 µm) chromatographic column with the mobile phases of 1 mM ammonium acetate aqueous solution and methanol solution and measured after positive and negative electrospray ionizations using four internal standards. To our knowledge, it was the first time to report the good performance of F5 column and four internal standards for the determination of amphenicols. The established method featured a good linear relationship between chromatographic peak area ratios and the concentrations of amphenicols (R² > 0.992), a wide and low detection matrix-based range of 0.01–5 μg/L, a low detection limit of 0.01 μg/kg, etc. The spiked assays evidenced the accuracy and reliability of the developed method with the recoveries between 84.0 and 105%, the intraday relative standard deviations (RSDs) over the range of 0.769–13.7%, and the interday RSDs over the range of 0.582–13.3%. Finally, the proposed method was applied to investigate amphenicol residues in various aquatic products, including fish, shrimp, crab, shellfish, and other aquatic species.

Aquatic products are good sources of essential nutrients, but the presence of pyrethroids (PYRs) as contaminants may pose risks to consumer health as the intricate matrices of PYRs usually obstruct chemical hazard detection. In this study, a gas chromatographic method was established and validated for simultaneously detecting residues of seven PYRs (cyhalothrin, permethrin, cyfluthrin, cypermethrin, tau-fluvalinate, fenvalerate, deltamethrin) in aquatic products. The aim of this method was to assess better the potential risks of pesticide residues in aquatic products. The PYRs in aquatic products were extracted with acetonitrile, purified with n-hexane saturated with acetonitrile, and cleaned up on a Cleanert^® Alumina N column. Statistical analysis and orthogonal array experimental design were used to optimize the key parameters. To validate the proposed method, commonly consumed aquatic products (such as carp, crucian carp, whiteleg shrimp, river crab, sea cucumber, and scallop) were obtained from local supermarkets in Shanghai. Satisfied linearity of the calibration curves was achieved in a matrix-matched standard solution, with a correlation coefficient (R²) larger than 0.995. The average recoveries at five fortification levels varied from 77.0% to 117.2%, with relative standard deviations (RSDs) below 11.1%. Concerning electron capture detection, the limits of detection (LOD) and limits of quantification (LOQ) were 2.0–5.0 µg/kg and 5.0–10.0 µg/kg, respectively. These results demonstrate the high stability and sensitivity of this method for simultaneously detecting PYRs in aquatic products, having great practicability and which can be popularized easily.

This study systematically deciphers a comprehensive analysis of biochemical and sensory variations in Takifugu obscurus, evaluating the seasonal dynamics, salinity gradients (0 and 3‰), and nutritional regimes on quality determinants in aquaculture. To the best of our knowledge, the mechanistic links between cultivation factors and organoleptic quality were first established through integrative biochemical profiling, including proximate composition, free amino acids, taste-active nucleotides, and mineral ions, coupled with quantitative sensory evaluation. The results revealed that spring samples exhibit 44.7% higher inosine monophosphate than that of autumn and 92.8% elevated ATP, correlating with superior umami-kokumi attributes. Salinity adaptation drove metabolic trade-offs: freshwater cultivation amplified flavor-enhancing amino acids, while brackish systems prioritized ionic precision. Short-term fasting induced alanine accumulation without sensory compromise, demonstrating nutritional plasticity. Polyculture compatibility was evidenced by negligible quality divergence from monoculture, despite enhanced productivity. These insights advance sustainable aquaculture through science-driven strategies that harmonize ecological resilience, economic viability, and culinary excellence in commercial Takifugu obscurus production.

Glucocorticoid (GC) residues present in aquatic products raise food safety concerns, as their chronic dietary intake may pose potential risks of endocrine and metabolic disruption. For the first time, a sensitive and reliable liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was developed and validated herein for the simultaneous determination of 12 GCs residues, including critical isomeric pairs and acetate ester derivatives, in a variety of aquatic foods, employing deuterated isotopic internal standards. Key optimizations included using a pentafluorophenyl column for effective isomer separation, a synergistic extraction system for high recovery, and QuEChERS purification to mitigate matrix effects. The method exhibited excellent linearity (r² > 0.996) and high accuracy (recoveries 97.3–99.3%), and the intra- and inter-day precision values were below 3% in five representative aquatic matrices, with a limit of detection (LOD) and a limit of quantification (LOQ) of 0.5 μg/kg and 0.75 μg/kg, respectively. Animal experiments confirmed the in vivo retention of acetate derivatives, justifying their inclusion in monitoring. Real sample analysis of 18 market samples revealed the presence of cortisone and hydrocortisone in 17 samples. This represents the first reported LC-MS/MS method that provides a sensitive, reliable tool for regulatory monitoring of GC residues in diverse aquatic products, thereby supporting food safety assurance.

Cadmium (Cd) hyperaccumulation in Portunus trituberculatus poses food safety concerns, yet tissue-specific distribution during gonadal maturation remains unresolved. Previous studies mixed hepatopancreas and gonads as “brown meat”, leading to debate over whether gonads act as the primary Cd storage site. Here, we systematically investigated Cd dynamics across six ovarian developmental stages using precise dissection and ICP-MS. Results showed that hepatopancreas was the dominant Cd reservoir, accounting for ≥97% of total Cd in edible tissues (11.3–42.9 mg/kg wet weight). Cd concentrations in ovary were extremely low (0.162 mg/kg) and near detection limit in eggs (0.070 mg/kg), demonstrating that gonads are not major accumulation sites. Hepatosomatic index (HSI) declined significantly during vitellogenesis, while ovarian Cd showed stage-specific fluctuation. This study clarifies Cd partitioning in swimming crabs, provides mechanistic insights into Cd detoxification, and offers evidence for safe consumption and regulatory standards.

To investigate the patterns of cadmium accumulation and distribution in mice following oral ingestion of cadmium-enriched Portunus trituberculatus, this study selected 4-week-old ICR mice as a model organism. A control group was fed a standard diet, while an exposure group was fed a diet supplemented with 10% cadmium-enriched Portunus trituberculatus. After 28 consecutive days of exposure, the mice were switched to a standard diet for 7 days. Tissues and feces were collected throughout the experiment; cadmium levels were determined by inductively coupled plasma mass spectrometry (ICP-MS) following microwave digestion. The results showed that after 28 days of exposure, cadmium accumulation was observed in the kidneys (females: 0.046 ± 0.001 mg/kg, males: 0.053 ± 0.005 mg/kg) and livers (females: 0.046 ± 0.008 mg/kg, males: 0.034 ± 0.001 mg/kg), while levels in the control group were below the limit of detection; After a subsequent 7-day period of feeding standard diet, cadmium accumulation was observed in the kidneys (females: 0.070 ± 0.001 mg/kg, males: 0.047 ± 0.006 mg/kg), livers (females: 0.040 ± 0.001 mg/kg, males: 0.035 ± 0.009 mg/kg), and the intestines (females: 0.028 ± 0.006 mg/kg, males: 0.029 ± 0.001 mg/kg) still contained trace amounts of cadmium that had not been excreted. An apparent mass balance analysis suggested that more than 90% of ingested Cd was not retained in the analyzed tissues. In summary, although cadmium ingested orally is primarily excreted, the clearance rate for cadmium accumulated in the liver and kidneys of mice is relatively low, and residual levels remain in the tissues even 7 days after exposure ceased, indicating that even when the majority of ingested Cd is eliminated, the fraction retained in target organs may persist after exposure cessation and warrants further investigation under longer-term exposure scenarios.