The quality of surface water could be influenced by both anthropogenic and natural factors. This study was designed to determine the impact of informal settlement and wastewater treatment plants on helminth egg contamination of urban rivers and the risks associated with everyday use. We also ascertained the accumulation of these eggs in the river sediments. The study was carried out in two rivers in the eThekwini Municipality of South Africa. Grab samples were taken at different points over a 10-month period. Ascaris spp., hookworm, Toxocara spp., Trichuris spp. and Taenia spp. were the helminth eggs detected in both the water column and sediments, with mean Ascaris spp. eggs of 0–6.3 (± 5.1)/L in the water and 0–6.8 (± 5.2)/kg in sediment samples. The helminth egg concentrations showed seasonal variation, probably due to changes in infection levels of the populations or natural factors, such as rainfall. The informal settlements had a greater impact than treated wastewater. For every 10,000 recreational users of the rivers 19 to 58 may be infected under undisturbed conditions, increasing to 29–88 individuals when the riverbed is disturbed. The risk from agricultural use of the rivers was above the tolerable risk values applicable for wastewater reuse, recommended by the World Health Organization. This calls for a re-evaluation of the policies governing surface water quality assessment, where the inclusion of helminth eggs and sediment monitoring will be critical.

人为和自然因素都可能影响地表水的质量。本研究旨在确定非正式住区和废水处理厂对城市河流蠕虫卵污染的影响以及与日常使用相关的风险。我们还确定了这些卵在河流沉积物中的积累。这项研究是在南非eThekwini市的两条河流中进行的。在10个月内的不同时间点采集了抓取的样本。蛔虫属，钩虫，弓蛔虫属，鞭虫属。和Ta虫属。在水柱和沉积物中均检测到蠕虫卵，平均A虫病spp。水中的卵数为0–6.3（±5.1）/ L，沉积物样本中的卵为0–6.8（±5.2）/ kg。蠕虫卵的浓度呈季节变化，可能是由于种群感染水平的变化或降雨等自然因素造成的。非正式住区的影响大于经处理的废水。在不受干扰的条件下，河水的每10,000个娱乐用户中有19至58人被感染，当河床受到干扰时，这一数字增加到29至88人。河流农业利用带来的风险高于世界卫生组织建议的适用于废水回用的可容忍风险值。这就要求对地表水质量评估政策进行重新评估，在该政策中，包括蠕虫卵和沉积物监测将至关重要。