Studies On The Effect Of Sulfonamide On Environmental Pollution And Its Degradation

Food safety is always a hot issue of social concern.There are many reasons leading to the trust crisis for food safety,among which the pollution of veterinary drugs is the main factor.The study has investigated the pollution status of sulfonamides in livestock and poultry dung as well as soil around typical farms.This experiment also studied the transfer trend of common veterinary drugs in soil-chicken manure-vegetable system and the elimination effect of different cooking treatment.The study included four parts as follows:Trial 1 was conducted to study the pollution status of sulfonamides in livestock and poultry in typical farms.The residues of five sulfonamides(sulfadiazine,sulfamethoxazole,sulfamethazine,sulfamonomethoxine,sulfaquinoxaline)from 21 fecal samples taken from province A,B and C from June to August 2016 were selected by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The results showed that the pollution levels of sulfonamides in various regions,sources,types and states were different.The overall pollution of sulfonamides was from high to low:sulfaquinoxaline,sulfamonomethoxine,sulfamethazine,sulfamethoxazole.The detection rate of sulfonamides was high,except sulfadiazine,the other four sulfonamides were detected.Compared with Province A,the residual amounts of sulfonamides in Province B and C were lower.Trial 2 was conducted to study the pollution status of sulfonamides in typical livestock farm and its surrounding soil.Sixty soil samples were selected from farm and vegetable planting base in Province A,B and C from June to August 2016,and the residues of five sulfonamides in samples were detected by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The results showed that the pollution levels of sulfonamides in soil samples varied due to different provinces,soil layers and sources.The detection rate of sulfonamides was high,except sulfadiazine,the other four sulfonamides were detected.The soil layer of 0-20 cm is significantly higher than the 20-40 cm soil layer.The overall pollution of sulfonamides was from high to low:sulfamonomethoxine,sulfamethoxazole,sulfamethazine,sulfaquinoxaline.Trial 3 was conducted to study the effect of sulfonamides(sulfamethazine)in chicken manure with time degradation.Designed to add 10 mg of sulfamethazine to 100 g of chicken manure,placed in dark light away,using the same concentration of florfenicol drug control group,the concentration of veterinary drugs in the 3th,12th and 20th day were detected by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The results showed that the difference during the 3th,12th and 20th day in the process of the degradation of chicken manure was large(P<0.05)and the difference in the 12th and the 20th days was not significant(P>0.05).The degradation of Sulfamethazine in chicken manure has negative curve relationship with time change.The degradation curve of sulfamethazine with time is y = 1612.3x-1 172,R2 = 0.9287.The control group of the drug group fluphenicol,which is degraded in chicken manure,is the same as sulfadiazine,the degradation curve of fluorobennin over time is y = 2.5762x-1.88,R2 = 0.9596.Trial 4 was conducted to study the migration of sulfonamides(sulfamethazine)in soil-chicken manure-vegetable system and the effect of different cooking methods on the elimination of drugs.Each group(630 cm2)was designed 150 g of chicken manure and 200 mg of sulfamethazine,and set up a control group of fluphenicol drugs at the same concentration.Green vegetables are sampled in diagonal lines,followed by the 7th,13th and 18th day.They can be stir-fried,boiled and blanched in three different ways,after sample treatment,the concentration of the veterinary drug was measured in high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The results showed that the residual differences were not significant in the samples of green vegetables in the 7th,13th and 18th day(P>0.05).Florfenicol was in the absorption and enrichment stage from the 7th to the 13th day,and it was in desorption from the 13th day to the 18th day,as well as sulfamethazine.The detection value of florfenicol was the highest at the 13th day.There were significant differences in the content of fluorobenzene in the green vegetablesin in the 7th,13th and 18th day(P<0.05).There were significant differences in sulfanilamide between this two kinds of cooking methods in the process of fiying oil(P<0.05).Boiling mode is same with Poached mix(P>0.05).The elimination ability of sulfamethazineand florfenicol in green vegetables was different in various cooking methods,and the elimination ability of frying oil was worst.There were significant differences in the three cooking methods between the control drug florfenicol(P<0.05).