AbstractsMedical & Health Science

Partition and survival of fecal indicators between sand and water of beaches in Hawaii

by Fan Feng




Institution: University of Hawaii – Manoa
Department:
Year: 2016
Keywords: Fecal Indicator Bacteria; Beach Sand; Rainfall; PCR
Posted: 02/05/2017
Record ID: 2063616
Full text PDF: http://hdl.handle.net/10125/101657


Abstract

M.S. University of Hawaii at Manoa 2010. Beaches are always the ideal ocean vacation destination to relax, and most people in tropical regions like to spend time on the beach. Hawaii has some of the best beaches in the world, attracting great numbers of visitors as well as local residents. The environmental quality of beaches, including beach sand and beach water, are essential to the health and safety of beach users and residents. However, in recent years, bacteriological contamination of beaches has steadily increased nationwide, and public concerns on the health and safety of beach usage have raised considerablely. A survey of water quality at U.S. beaches by National Research Defense Council (NRDC) indicated that in 2009 beach water pollutions caused beach closings and advisories to reach their sixth-highest level in 20 years, exceeding 20,000 for the fourth consecutive year (1). In Hawaii, a different trend has been observed. In the past five years, the highest number of total closing/advisory days was in 2006 (6,507 days) while a significantly reduced number of closing/advisory days (2,352 days) were reported in 2009, which are likely due to variations in heavy rainfall frequencies, as more than 99% of the closing/advisory days were issued due to anticipated rainfall events (1). One primary concern of beach water pollution is the increased health risks to beach users. Polluted beach sand and water by untreated sewage and human and animal wastes may contain harmful bacteria and pathogens that post direct health risk to beach users especially children. Diseases caused by waterborne pathogen include gastroenteritis; hepatitis A; ear, nose, and throat infections; severe respiratory ailments; diarrhea; and rashes. In order to reduce illnesses associated with recreational water usages, state governments are required by the Beaches Environmental Assessment and Coastal Health Act (BEACH) to conduct beach monitoring programs and assess potential risks using fecal indicator bacteria (FIBs) (2). Another important issue concerns the sources of beach contamination. Potential primary sources of beach contamination usually include rainfall events, sewage outflows (3), birds and other animal feces (4), human activities and leaking septic systems. Heavy rainfall (5) or onshore wind events can significantly increase the contamination level. The fecal indicator bacteria may also come from secondary sources in the environment; for example, beach foreshore sands have been widely reported to harbor high levels of indicator organisms.