Clark Catherine D, De Bruyn Warren J, Jakubowski Scott D, Grant Stanley B
Department of Chemistry, Chapman University, One University Drive, Orange, CA 92866, USA.
Mar Pollut Bull. 2008 Mar;56(3):397-401. doi: 10.1016/j.marpolbul.2007.10.017. Epub 2007 Dec 11.
Hydrogen peroxide concentrations [H(2)O(2)] have been measured over the last two decades in multiple studies in surface waters in coastal, estuarine and oceanic systems. Diurnal cycles consistent with a photochemical production process have frequently being observed, with [H(2)O(2)] increasing by two orders of magnitude over the course of the day, from low nM levels in the early morning to 10(2)nM in late afternoon. Production rates range from <10 for off-shore ocean waters to 20-60nMh(-1) for near-shore coastal and estuarine environments. Slow night-time loss rates (<10nMh(-1)) have been attributed to biological and particle mediated processes. Diurnal cycles have also frequently been observed in fecal indicator bacteria (FIB) levels in surf zone waters monitored for microbial water quality. Measured peak peroxide concentrations in surface coastal seawaters are too low to directly cause FIB mortality based on laboratory studies, but likely contribute to oxidative stress and diurnal cycling. Peroxide levels in the surf zone may be increased by additional peroxide production mechanisms such as deposition, sediments and stressed marine biota, further enhancing impacts on FIB in marine bathing waters.
在过去二十年里，多项研究对沿海、河口和海洋系统中的地表水进行了过氧化氢浓度[H₂O₂]的测量。经常观察到与光化学生产过程一致的日循环，[H₂O₂]在一天内增加两个数量级，从清晨的低纳摩尔水平增加到傍晚的10²纳摩尔。生产率范围从离岸海水的<10到近岸沿海和河口环境的20 - 60纳摩尔/小时。夜间缓慢的损失率（<10纳摩尔/小时）归因于生物和颗粒介导的过程。在监测微生物水质的冲浪区水域中，粪便指示菌（FIB）水平也经常观察到日循环。根据实验室研究，沿海表层海水中测得的过氧化氢峰值浓度过低，无法直接导致FIB死亡，但可能会导致氧化应激和日循环。冲浪区的过氧化物水平可能会因沉积、沉积物和受胁迫的海洋生物群等额外的过氧化物产生机制而增加，进一步增强对海水浴场中FIB的影响。
