东莞市蔬菜基地土壤中四环素类抗生素的含量与分布

利用高效液相色谱-串联质谱(LC-MS/MS)分析方法,探讨了东莞市18个区镇24个代表性蔬菜基地土壤中4种四环素类(四环素、土霉素、金霉素、强力霉素)抗生素的含量与分布特征.结果表明,4种抗生素总含量为0~138.86μg/kg,低于10μg/kg占总样本数59%,平均为20.85μg/kg.各化合物检出率为59%~89%,含量为0~103.40μg/kg,绝大多数在10μg/kg以下,以土霉素(平均含量8.95μg/kg)为主,其次是强力霉素(平均含量5.45μg/kg)和金霉素(平均含量5.13μg/kg).不同基地土壤中四环素类化合物的组成与含量特征差异较大,主要有以土霉素为主、以金霉素为主、以强力霉素为主和以土霉素+强力霉素为主4种组成模式.同一基地种植不同蔬菜土壤中四环素类化合物的组成与含量特征差异较小.

Concentration and distribution of tetracycline antibiotics in soils from vegetable fields of dongguan City

The concentration and distribution of four tetracycline antibiotics (TCs) including tetracycline(TC), oxytetracycline (OTC), chlortetracycline (CTC) and deoxytetracycline (DC) in soils from 24 typical vegetable fields in 18 towns of Dongguan city using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was discussed. The total concentrations of four tetracycline antibiotics (∑TCs) ranged from 0 (below LOQ) to 97.04μg/kg, which predominated with under 10μg/kg and averaged at 13.42μg/kg. The concentrations of four tetracycline compounds detected in 59~89% of the samples ranged from 0 (below LOQ) to 75.29μg/kg which falls mostly bellow 10μg/kg. Oxytetracycline which averaged at 6.51μg/kg was dominant compound, followed by chlortetracycline and deoxytetracycline which averaged at 2.95μg/kg and 2.92μg/kg respectively. The concentration and constitute of tetracycline compounds in soils from different vegetable fields varied greatly, consisting mainly of four models, i.e. the first one dominated with oxytetracycline, the second one dominated with chlortetracycline, the third one dominated with deoxytetracycline, and the last one dominated with both oxytetracycline and deoxytetracycline. However, the concentrations and constitute of tetracycline compounds in soils grown different cultivars within the same vegetable fields varied weakly. The concentrations of tetracycline antibiotics in soils from vegetable fields of Dongguan city were generally lower and less ecotoxic risk for soil ecosystem. But it should not be ignored as to combined toxic effect and resistance of various compounds.