Dep. of Crop and Soil Sciences, Michigan State Univ., East Lansing, MI 48824, USA.
J Environ Qual. 2010 Jul-Aug;39(4):1211-7. doi: 10.2134/jeq2009.0090.
Veterinary pharmaceuticals are commonly administered to animals for disease control, and added into feeds at subtherapeutic levels to improve feeding efficiency. As a result of these practices, a certain fraction of the pharmaceuticals are excreted into animal manures. Land application of these manures contaminates soils with the veterinary pharmaceuticals, which can subsequently lead to contamination of surface and groundwaters. Information on the occurrence and fate of pharmaceuticals in soil and water is needed to assess the potential for exposure of at-risk populations and the impacts on agricultural ecosystems. In this study, we investigated the occurrence and fate of four commonly used veterinary pharmaceuticals (amprolium, carbadox, monensin, and tylosin) in a farm in Michigan. Amprolium and monensin were frequently detected in nearby surface water, with concentrations ranging from several to hundreds of nanograms per liter, whereas tylosin or carbadox was rarely found. These pharmaceuticals were more frequently detected in surface runoff during nongrowing season (October to April) than during growing season (May to September). Pharmaceuticals resulting from postharvest manure application appeared to be more persistent than those from spring application. High concentrations of pharmaceuticals in soils were generally observed at the sites where the respective concentrations in surface water were also high. For monensin, the ratios of soil-sorbed to aqueous concentrations obtained from field samples were within the order of the distribution coefficients obtained from laboratory studies. These results suggest that soil is a reservoir for veterinary pharmaceuticals that can be disseminated to nearby surface water via desorption from soil, surface runoff, and soil erosion.
兽用药品通常用于动物疾病控制，并以低于治疗水平的剂量添加到饲料中以提高饲养效率。由于这些做法，一部分药品会排泄到动物粪便中。这些粪便的土地应用会使土壤受到兽用药品的污染，从而可能导致地表水和地下水的污染。为了评估高风险人群暴露的可能性和对农业生态系统的影响，需要了解药品在土壤和水中的存在和归宿信息。在本研究中，我们调查了密歇根州一个农场中四种常用兽用药品（安普罗姆、卡巴多、莫能菌素和泰乐菌素）的存在和归宿。安普罗姆和莫能菌素经常在附近的地表水，浓度从数纳克/升至数百纳克/升不等，而泰乐菌素或卡巴多则很少发现。这些药品在非生长季节（10 月至 4 月）比生长季节（5 月至 9 月）期间更频繁地出现在地表径流中。收获后粪便施用产生的药品似乎比春季施用产生的药品更持久。在地表水浓度也较高的地点，土壤中通常观察到高浓度的药品。对于莫能菌素，从田间样本中获得的土壤吸附与水相浓度之比在实验室研究中获得的分配系数范围内。这些结果表明，土壤是兽用药品的储存库，这些药品可以通过土壤解吸、地表径流和土壤侵蚀从土壤传播到附近的地表水。
