College of Natural Resources and Environment, South China Agricultural University, Wushan, 510642, Guangzhou, China.
Institute of Global Food Security, Queen's University Belfast, Belfast, BT9 7BL, UK.
Environ Sci Pollut Res Int. 2019 Feb;26(6):6209-6215. doi: 10.1007/s11356-018-04077-y. Epub 2019 Jan 7.
The environmental and human health risk posed by veterinary antibiotics is of global concern. Antibiotic uptake by herbal plants has been studied, but little is known about perennial woody fruit crops. Litchi (Litchi chinensis Sonn.), a longevial fruit tree, is routinely fertilized with animal manure and, therefore, may be at risk of antibiotic uptake into its fruits. This study investigated the degradation of chlortetracycline and doxycycline present in manure used to amend orchard soil, and their subsequent assimilation by litchi plant, as affected by manure application rate. The results show that half-lives of chlortetracycline and doxycycline in soil were decreased by increased manure rate, with an average of 27 and 59 days, respectively. Chlortetracycline was readily transported to litchi shoots and increased with the growth of litchi plants. Doxycycline predominantly remained in the roots, and underwent growth dilution in the plants. The two tetracyclines could not be detected in fruits from litchi trees when applied with manures, at various rates, over 2 years. For litchi, chlortetracycline may pose human health risk through manure application, but doxycycline is unlikely to do so. Long-term field experiments are required to monitor antibiotic accumulation in fruits of perennial fruit trees fertilized with animal manure.
兽用抗生素对环境和人类健康构成的风险引起了全球关注。人们已经研究了植物对抗生素的吸收情况，但对多年生木本水果作物的相关情况知之甚少。荔枝（Litchi chinensis Sonn.）是一种长寿水果树，通常用动物粪便施肥，因此，其果实可能有摄入抗生素的风险。本研究调查了施用于果园土壤的粪便中存在的金霉素和强力霉素的降解情况，以及它们随后被荔枝植物吸收的情况，这受到粪便施用量的影响。结果表明，粪便施用量的增加会缩短金霉素和强力霉素在土壤中的半衰期，分别平均为 27 天和 59 天。金霉素很容易被转运到荔枝嫩枝中，并随着荔枝植物的生长而增加。强力霉素主要存在于根部，并在植物中经历生长稀释。在两年多的时间里，以不同的速率施用粪便后，在荔枝果实中无法检测到这两种四环素。对于荔枝来说，通过施用粪便，金霉素可能会对人类健康构成风险，但强力霉素不太可能这样。需要进行长期田间试验来监测用动物粪便施肥的多年生果树果实中的抗生素积累情况。
