Cumulative Toxicity of Residue Degradation Products of Penicillin Bacteria

[Objective] The research aimed to discuss the accumulation of toxic slag of penicillin bacteria residue degradation products and explore its ability to meet the aquaculture industry as a protein feed into development and utilization conditions.[Method] Through the sub-acute toxicity tests in mice strains,which were fed by different doses of penicillin bacteria residue degradation products （3% and 6%） under continuous observation of 15 weeks,recording a weekly mouse weight and death,and sampling executed after the test,animal liver and kidney function were blood test,taking heart,liver,spleen,kidney weighing,as well as liver and kidney pathology observed in the optical microscope.[Result] There were no significant differences （P 0.05） between the test group mice body weight,mortality and liver and kidney function and the control group within 15 weeks.Low-dose test group could be seen the liver cells,renal tubular epithelial nuclei broken,and a small number of liver and kidney cells with mild edema.High-dose test group could be seen in liver tissue of mice nuclei fragmentation and a fat droplets,the majority of liver cells,edema,and only a small number of liver cells,there were no significant changes.Renal portal area showed inflammatory cell infiltration,renal tubular epithelial cells,edema and necrosis.[Conclusion] In this experimental condition,the degradation products of penicillin bacteria residue played a mild toxcity on organ parenchymal cells in mice.

Multiresidue determination and potential risks of emerging pesticides in aquatic products from Northeast China by LC-MS/MS

A simple method for determining 33 pesticides with a wide polarity range（log Kow0.6-4.5） in aquatic products was developed based on LC–MS/MS. The target analytes included three types of widely used pesticides： insecticides, fungicides and herbicides. Based on the optimization of ultrasonic assisted extraction and GPC clean-up procedures, the matrix effect, extraction recoveries and LOD were improved distinctively. LOQ of this method was below 0.5 ng/g for all pesticides, which is superior to values in the literature, and the matrix effect was reduced effectively（-14.7% to 7.5%）. The method was successfully applied to investigate the pesticide residue levels of twenty-five samples including seven common kinds of fishes from Northeast China. The results showed that all targeted pesticides were present in the fish samples; however, their levels were low, except for atrazine, linuron,ethoprophos, tetrachlorvinphos, acetochlor and fenthion. Atrazine and linuron caught our attention because the concentrations of atrazine in fish samples from Liaoning province were in the range of 0.5-8 ng/g（w/w） with mean concentration of 2.3 ng/g, which were far above those of other pesticides. The levels of linuron were in the range of 0.6-6 ng/g（mean concentration 2.8 ng/g）, which were the highest among all targeted pesticides in the Inner Mongolia. This is the first systematic investigation on the characteristics and levels of these pesticides in aquatic products from northeast China. Considering their toxicity and bioaccumulation, the potential risk of atrazine and linuron from consuming aquatic products should be paid more attention.