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Phosphate levels starkly higher in Bolong Feyno water samples

“Report # 39461706 of Reef Analytics shows that phosphate levels in the sample of seawater collected from the Bolong Fenyo Wildlife Reserve on 22 May 2017 are starkly higher than maximum levels necessary for the protection of marine aquatic life:”


Thank you for sharing the lab report, which presents information about the concentration of substances in a sample of seawater collected from the Bolong Fenyo Wild Reserve on 22 May 2017. The result that stands out is the alarmingly high levels of phosphate in the seawater sample. According to the WB/IFC document I sent earlier (“Environmental, Health, and Safety Guidelines for Fish Processing).”  “Fish processing wastewater has a high organic content, and subsequently a high biochemical oxygen demand (BOD), because of the presence of blood, tissue, and dissolved protein. It also typically has a high content of nitrogen (especially if blood is present) and phosphorus.” 

The problem with excess levels of phosphate in aquatic systems (both marine and freshwater) is that phosphate stimulates the growth of bacteria and algae, resulting in deleterious changes in water quality, including depletion of dissolved oxygen, in a process called ‘eutrophication.’ Please see the attached document (Chongprasith, P., Wiliratanadilok, W., & Utoomprurkporm, W. (1999). ASEAN marine water quality criteria for phosphate. ASEAN-Canada CPMS-II Cooperative Programme on Marine Science. Department of Pollution Control, Thailand), which I quote from below: “2.3 Concentration of Phosphate in the Marine Environment “In surface waters, phosphate concentrations are usually very low, less than 31 μg/L (Valiela, 1984), primarily due to the uptake of phosphate by algae and bacteria “Marine environmental monitoring studies conducted in the ASEAN region showed that phosphate concentrations in coastal sea water ranged from below detection limits to 195.92 μg/L and the concentrations found in estuaries were <3.1 - 179.8 μg/L as shown in Table 1. Highest concentrations of phosphate were found in river mouth areas and coastal waters affected by runoff. …. “3.0 EFFECTS ON AQUATIC LIFE “The main deleterious effect of phosphate in coastal waters is eutrophication. While phosphate is an essential nutrient required for normal productivity, elevated concentrations can result in an upset of the ecological balance of tropical marine systems. Unlike some other chemicals (e.g., heavy metals), phosphate is not toxic in the usual sense. Rather, it causes ecological changes that can have negative impacts on aquatic systems. Therefore, derivation of an AMEQC for phosphate depends more on information about the biological effects of phosphate, as opposed to its toxicity. …. “3.1 General Background on Phosphate “Phosphate itself is not directly harmful (i.e., toxic) to marine organisms at concentrations found in the marine environment. However, high concentration of phosphates can lead to eutrophication, which is the process that occurs when nutrient levels increase and encourage the over-production of plants and algae. This process occurs naturally and there are many historical records which report such events long before extensive urban development and the use of artificial fertilisers and detergents. However, anthropogenic nutrient inputs have accelerated this process in many areas. Conditions favouring eutrophication usually occur during dry seasons when water flows are low, causing nutrient concentrations to rise. … “3.3.3 Recommended Criteria For Dissolved Reactive Phosphorus “Australia and Hawaii have marine water quality guidelines for total phosphorus. Australia limits total phosphorus concentrations to 5 μg/L in coastal waters and 10 μg/L in estuarine waters (ANZECC, 1992). Hawaii has developed separate total phosphorus guidelines for various marine water body types (i.e., estuary, embayments, coastal and oceanic) and seasons (i.e., wet and dry). Guidelines range from 16 μg/L (geometric mean of measured values in open coastal waters during dry season) to 75 μg/L (not to be exceeded more than 2% of the time in embayments during the wet season). “Based on the above information, interim criteria for dissolved reactive phosphorus were derived for estuarine (45 μg/L) and coastal waters (15 μg/L). These criteria are intended to protect coastal waters from eutrophication. Compared to the ambient concentrations of dissolved reactive phosphorus in the ASEAN region, 65% of the maximum and 89% of the minimum concentrations fall below 45 μg/L, while 40% of the maximum and 77% of the minimum concentrations fall below 15 μg/L. The criteria are designated as interim due to the lack of data linking dissolved reactive phosphorus (or even total phosphorus) to eutrophic conditions in the ASEAN tropical marine environment.” Report # 39461706 of Reef Analytics shows that phosphate levels in the sample of seawater collected from the Bolong Fenyo Wildlife Reserve on 22 May 2017 are starkly higher than maximum levels necessary for the protection of marine aquatic life:

Editor’s note:

The Interpretation of water quality data of water samples from Bolong Feyno was done by Mark Chernaik who is one of the technicians who carried out the test at REEF Analytics laboratory in Germany.

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