Freshwater harmful algal blooms (HABs) have become a global concern because blooms contain cyanotoxins that can cause liver damage and other negative health impacts. In South Korea, HABs have been frequently observed along the major rivers (Han, Geum, Nakdong, and Youngsan) in recent years. However, there are hardly any studies that report a linkage between HABs and human health, especially along the four major rivers where dams, weirs, and reservoirs were constructed, and sediments were dredged under the Four Major Rivers Project (FMRP) that ended in 2012. The goals of this study were to summarize spatial distribution patterns of HABs and investigate a potential association between HABs and liver diseases. Chlorophyll-a concentration was used to estimate bloom intensity since it was the only available bloom-related parameter that covers the entire rivers. Liver disease data (ICD-10 codes: K71–K77) were sorted by administrative districts. Generalized linear mixed model was used to analyze the bloom, liver diseases, and population data (2005–2016). The results show that chlorophyll-a levels significantly increased since 2013, except Han River region. There was a significant association between HAB intensity and incidence rate of liver diseases, except Han River area, and the extent of association significantly increased after the completion of the FMRP. For future studies, more in-depth epidemiological investigations are warranted in those areas to accurately determine more specific associations between HABs and liver diseases as well as other bloom-related diseases and symptoms. In addition, identification of major exposure pathways to cyanotoxins is needed to better protect public health in those bloom-affected areas.

淡水有害藻华（HABs）已成为全球关注的问题，因为藻华中含有可能导致肝损害和其他负面健康影响的氰毒素。近年来，在韩国，沿主要河流（汉，金，纳东和永山）经常观察到HAB。但是，几乎没有任何研究报告说HAB与人类健康之间存在联系，尤其是在四大河流中，这些大坝是在2012年结束的四大河流项目（FMRP）下建造大坝，堰坝和水库，疏sediment了沉积物这项研究的目的是总结HAB的空间分布模式，并调查HAB与肝病之间的潜在关联。由于叶绿素a浓度是覆盖整个河流的唯一可用的与开花相关的参数，因此使用叶绿素a浓度来估计开花强度。肝病数据（ICD-10代码：K71–K77）按行政区分类。广义线性混合模型用于分析霜华，肝脏疾病和种群数据（2005–2016）。结果表明，自2013年以来，除汉江地区外，叶绿素a水平显着增加。除汉江地区外，HAB强度与肝病发病率之间存在显着相关性，FMRP完成后相关性程度显着增加。为了将来的学习，在这些领域中，需要进行更深入的流行病学调查，以准确确定HAB与肝病以及其他与花粉病相关的疾病和症状之间的更具体关联。此外，需要确定主要的蓝藻毒素接触途径，以更好地保护那些受花开的地区的公共健康。