Hashiguchi Yuya, Zakaria Mohd Rafein, Toshinari Maeda, Mohd Yusoff Mohd Zulkhairi, Shirai Yoshihito, Hassan Mohd Ali
Division of Environmental Bio-Adaptation, Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka, Japan; Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia; Laboratory of Processing and Product Development, Institute of Plantation Studies, University Putra Malaysia, 43400, UPM, Serdang, Selangor, Malaysia.
Environ Pollut. 2021 May 15;277:116780. doi: 10.1016/j.envpol.2021.116780. Epub 2021 Feb 19.
Most palm oil mills adopted conventional ponding system, including anaerobic, aerobic, facultative and algae ponds, for the treatment of palm oil mill effluent (POME). Only a few mills installed a bio-polishing plant to treat POME further before its final discharge. The present study aims to determine the quality and toxicity levels of POME final discharge from three different mills by using conventional chemical analyses and fish (Danio rerio) embryo toxicity (FET) test. The effluent derived from mill A which installed with a bio-polishing plant had lower values of BOD, COD and TSS at 45 mg/L, 104 mg/L, and 27 mg/L, respectively. Only mill A nearly met the industrial effluent discharge standard for BOD. In FET test, effluent from mill A recorded low lethality and most of the embryos were malformed after hatching (half-maximal effective concentration (EC50) = 20%). The highest toxicity was observed from the effluent of mill B and all embryos were coagulated after 24 h in samples greater than 75% of effluent (38% of half-maximal lethal concentration (LC50) at 96 h). The embryos in the effluent from mill C recorded high mortality after hatching, and the survivors were malformed after 96 h exposure (LC50 = 26%). Elemental analysis of POME final discharge samples showed Cu, Zn, and Fe concentrations were in the range of 0.10-0.32 mg/L, 0.01-0.99 mg/L, and 0.94-4.54 mg/L, respectively and all values were below the effluent permissible discharge limits. However, the present study found these metals inhibited D. rerio embryonic development at 0.12 mg/L of Cu, and 4.9 mg/L of Fe for 96 h-EC50. The present study found that bio-polishing plant installed in mill A effectively removing pollutants especially BOD and the FET test was a useful method to monitor quality and toxicity of the POME final discharge samples.
大多数棕榈油厂采用传统的池塘系统，包括厌氧池、好氧池、兼性池和藻类池，来处理棕榈油厂废水（POME）。只有少数工厂安装了生物净化装置，以便在POME最终排放前进一步处理。本研究旨在通过常规化学分析和鱼类（斑马鱼）胚胎毒性（FET）试验，确定来自三个不同工厂的POME最终排放物的质量和毒性水平。来自安装了生物净化装置的工厂A的废水，其生化需氧量（BOD）、化学需氧量（COD）和总悬浮固体（TSS）的值较低，分别为45毫克/升、104毫克/升和27毫克/升。只有工厂A的BOD几乎达到了工业废水排放标准。在FET试验中，工厂A的废水致死率较低，大多数胚胎在孵化后出现畸形（半数最大效应浓度（EC50）=20%）。工厂B的废水毒性最高，在超过75%的废水样本中，所有胚胎在24小时后凝固（96小时时的半数最大致死浓度（LC50）为38%）。工厂C的废水胚胎在孵化后死亡率很高，在暴露96小时后，存活的胚胎出现畸形（LC50=26%）。对POME最终排放样本的元素分析表明，铜（Cu）、锌（Zn）和铁（Fe）的浓度分别在0.10 - 0.32毫克/升、0.01 - 0.99毫克/升和0.94 - 4.54毫克/升范围内，所有值均低于废水允许排放限值。然而，本研究发现，这些金属在浓度为0.12毫克/升的铜和4.9毫克/升的铁时，对斑马鱼胚胎发育有抑制作用，96小时的EC50为此浓度。本研究发现，安装在工厂A的生物净化装置能有效去除污染物，尤其是BOD，并且FET试验是监测POME最终排放样本质量和毒性的有用方法。
