Wheeler Alm Elizabeth, Burke Janice, Spain Anne
Department of Biology, Central Michigan University, 157 Brooks Hall, Mount Pleasant, MI 48859, USA.
Water Res. 2003 Sep;37(16):3978-82. doi: 10.1016/S0043-1354(03)00301-4.
Potential fecal contamination of sand in the wave-washed zone of public bathing beaches is overlooked in beach monitoring programs. Activity in this zone can bring pathogens to the sand surface or into the water, presenting a health risk to sensitive populations. On a unit weight basis (colony forming units per 100g), the mean summer abundance of the fecal indicator bacteria enterococci and Escherichia coli was 3-38 times higher in the top 20 cm of wet-sand cores than in the water column at six freshwater bathing beaches. E. coli were 4 times more abundant than enterococci in water but counts were similar in the sand. A correlation (r=0.60) existed between E. coli counts in the water and in the top 5 cm of sand only, whereas no relationship existed between enterococci abundance in water and sand. In general, enterococci were most numerous in the 5-10 cm sand stratum and E. coli in the 0-5 cm stratum. These preliminary data show that wet freshwater beach sand is a reservoir of fecal indicator bacteria. Enteric pathogens may also be present in beach sand.
在海滩监测项目中，公共浴场海滩波浪冲刷区域的沙子可能存在的粪便污染被忽视了。该区域的活动会将病原体带到沙面或水中，对易感人群构成健康风险。以单位重量计（每100克中的菌落形成单位），在六个淡水浴场海滩，湿沙芯顶部20厘米处粪便指示菌肠球菌和大肠杆菌的夏季平均丰度比水柱中的高3至38倍。水中大肠杆菌的丰度比肠球菌高4倍，但在沙子中的数量相似。仅在水中和沙面顶部5厘米处的大肠杆菌数量之间存在相关性（r = 0.60），而水中和沙子中的肠球菌丰度之间没有关系。一般来说，肠球菌在5至10厘米的沙层中数量最多，大肠杆菌在0至5厘米的沙层中数量最多。这些初步数据表明，潮湿的淡水海滩沙子是粪便指示菌的储存库。肠道病原体也可能存在于海滩沙子中。
