Measuring Water Pollution: Philippines' Aquatic Health Insights

Water pollution in the Philippines is a pressing issue with far-reaching consequences for the country's health, economy, and environment. With a growing economy and rapid urbanization, the Philippines faces significant challenges in providing adequate water and sanitation services to its population. The country's water sources, including rivers, lakes, and oceans, are threatened by various forms of pollution, such as industrial discharge, agricultural runoff, and inadequate domestic sewage treatment. These sources of pollution contribute to the deterioration of water quality, leading to environmental degradation, economic losses, and public health risks. Addressing water pollution in the Philippines requires strict regulations, improved sanitation infrastructure, and collaborative efforts between government, non-profit organizations, and local communities to implement sustainable solutions and ensure access to safe water for all.

Measuring dissolved oxygen (DO) levels

Water with high levels of dissolved oxygen (DO) is an indicator of good water quality. DO refers to the level of free, non-compound oxygen present in water or other liquids. It is essential for aquatic life, as it is used for respiration by fish, invertebrates, bacteria, and plants. The amount of DO needed varies from creature to creature. For example, bottom feeders, crabs, oysters, and worms need minimal amounts of oxygen (1-6 mg/L), while shallow-water fish need higher levels (4-15 mg/L).

DO levels are measured with a calibrated water quality probe meter, usually in conjunction with measurements for temperature and pH. While each organism has its own DO tolerance range, generally, DO levels less than 5mg/L are considered stressful for fish, and levels less than 3mg/L are too low to support fish. DO levels below 1mg/L are considered hypoxic and usually devoid of life.

DO levels in water bodies can fluctuate periodically, seasonally, and even daily. As DO levels drop, some sensitive animals may move away, decline in health, or even die. DO levels can be affected by various factors, such as water temperature, pressure, altitude, and salinity. For example, colder, deeper freshwater has the capability to hold higher concentrations of DO, while saltwater holds about 20% less DO than freshwater at the same pressure and temperature. Additionally, water at lower altitudes can hold more DO than water at higher altitudes.

Human activities can also impact DO levels in water bodies. For example, excess organic materials, such as large algal blooms, can cause a decrease in DO levels as they are decomposed by microorganisms. This can lead to low oxygen levels (hypoxia) or even an absence of oxygen (anoxia) in the water, affecting the health and survival of aquatic organisms.

Assessing pollution sources

Water pollution in the Philippines is a critical issue that affects the nation's health, economy, and environment. The country's water sources, including its rivers, lakes, and oceans, are facing significant pollution challenges. Assessing and identifying the sources of pollution is crucial for implementing effective measures to address this problem.

One approach to assessing pollution sources is to categorise water pollution into two types: point source pollution and non-point source pollution. Point source pollution refers to pollution with an identifiable source and a specific discharge point, such as industrial, agricultural, or domestic wastewater discharges. On the other hand, non-point source pollution has no known or identifiable source. Understanding these categories helps target interventions and regulations effectively.

To further pinpoint pollution sources, parameters such as dissolved oxygen (DO) and biological oxygen demand (BOD) are measured. DO indicates the level of water pollution and the capacity of the water body to support aquatic life. Water movement, temperature, and pollution can influence DO levels. BOD measures the amount of oxygen consumed by microorganisms during the decomposition of organic matter from pollution sources. This helps quantify the pollution contribution from different sectors.

The Philippines' water pollution is primarily attributed to industrial processes, agriculture, and domestic sewage. Industrial activities release pollutants like heavy metals, oils, solid waste, hazardous chemicals, and industrial wastewater. These toxins can bioaccumulate in animals and enter the human food chain. Agricultural pollution, including animal waste and pesticide and fertiliser runoff, also plays a significant role in water contamination. Inadequate domestic sewage treatment and plastic pollution further exacerbate the problem.

By employing these assessment methods and identifying the specific sources of pollution, targeted measures can be implemented to mitigate water pollution in the Philippines. This may include stricter regulations, improved sanitation infrastructure, increased treatment of domestic wastewater, and better management of industrial and agricultural waste.

Evaluating ambient water quality

The Philippines faces significant challenges in terms of water quality and sanitation access. The country's water availability and quality are alarming, with 43% of its rivers and 56% of its major water bodies polluted. The nation's oceans are in a similar state, with the Philippines being the world's leading ocean plastic polluter.

When evaluating ambient water quality in the Philippines, it is essential to consider the various sources of water pollution and their impacts on the environment and human health. Ambient water refers to natural bodies of water such as lakes, rivers, and oceans. The quality of these water sources is crucial for the country's drinking water supply, agriculture, and industry. Here are some key factors and methods for assessing ambient water quality:

• Sources of Pollution: Understanding the sources of water pollution is vital for effective evaluation and management. The main sources of water pollution in the Philippines are industrial processes, agricultural activities, and domestic sewage. These sources release untreated sewage, hazardous chemicals, heavy metals, oils, solid waste, and other pollutants into water bodies.
• Water Quality Parameters: The Philippines has legislations and standards in place to assess water quality. These include the Clean Water Act of the Philippines and the DENR Administrative Order No. 34 Series of 1990, which sets minimum and desired levels for drinking water quality. Key parameters to evaluate include:

• PH: The pH level of water is a measure of its acidity or alkalinity. Deviations from a neutral pH can indicate pollution or other issues.
• Dissolved Oxygen (DO): DO is a critical parameter as it indicates the level of water pollution and the capacity of the water body to support aquatic life. Higher levels of DO are generally observed in healthier water bodies.
• Biological Oxygen Demand (BOD): BOD measures the amount of oxygen consumed by microorganisms during the decomposition of organic matter from pollution sources. Higher BOD levels indicate higher levels of organic pollution.

• Point Source and Non-Point Source Pollution: It is important to distinguish between these two types of pollution. Point source pollution has an identifiable source and specific discharge point, such as industrial or agricultural wastewater discharges. Non-point source pollution has no known or identifiable source.
• Health and Environmental Impacts: Evaluating the health and environmental consequences of water pollution is crucial. Waterborne diseases, such as cholera, typhoid, dysentery, and hepatitis, are prevalent in areas with poor water quality and have severe impacts on public health. Additionally, plastic pollution from single-use packaging and other sources poses a significant threat to marine life and biodiversity.
• Regular Monitoring and Remediation: Regularly monitoring contaminant levels in water bodies is essential. This involves collecting and analysing water samples to assess the presence and concentration of pollutants. When pollution is identified, remediation programs should be implemented promptly to mitigate its effects.
• Enforcement and Policy Implementation: The lack of strict enforcement of regulations and policies can contribute to water pollution. It is crucial to establish government bodies or agencies responsible for enforcing effluent data collection and implementing remediation measures.

By considering these factors and employing a combination of scientific evaluation, regulatory compliance, and proactive remediation, the Philippines can effectively evaluate and improve its ambient water quality, ensuring the protection of its water resources, ecosystems, and public health.

Testing for heavy metals

Some of the most common heavy metals found in water include manganese, lead, arsenic, chromium, antimony, cadmium, selenium, and copper. While small amounts of some of these metals are essential for health, others, like lead and arsenic, are toxic. Industrial and agricultural operations are often responsible for introducing these metals into water supplies.

There are a variety of testing methods available to detect heavy metals in water. Spectrometry technologies, such as Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), are commonly used due to their sensitivity and precision in detecting multiple elements. Speciation analysis is also employed to test for specific toxic species of arsenic and mercury.

Several organizations offer heavy metal testing services and kits. For example, ETR Labs offers a heavy metal water test for $190, detecting a comprehensive range of metals and other contaminants. Rose City Laboratories provides a DIY heavy metals in the water testing kit, which includes certified bottles, instructions, labels, and postage for sending samples to their laboratory. Results are available within five business days.

Monitoring biological oxygen demand (BOD)

Water pollution in the Philippines is a critical issue, with the country facing challenges in providing safe water and sanitation access to its population. The main sources of water pollution in the country are industrial processes, agriculture, and domestic sewage, leading to poor water quality and negative health, economic, and environmental impacts.

Biochemical Oxygen Demand (BOD) is a crucial parameter in monitoring water quality and determining the impact of organic pollution in water. BOD analysis measures the amount of dissolved oxygen (DO) consumed by aerobic bacteria growing on the organic material present in a water sample at a specific temperature over a specified time period. This value is typically expressed in milligrams of oxygen consumed per liter of sample during a 5-day incubation period at 20°C.

• Collect a water sample from the source to be tested. The sample should be representative of the water body and collected following standard methods to ensure accuracy.
• Prepare a sealed container fitted with a pressure sensor. The container should be clean and free from any contaminants that may interfere with the results.
• Add a substance that absorbs carbon dioxide, such as lithium hydroxide, above the sample level within the container. This step is crucial as it helps measure the oxygen consumption accurately.
• Store the sample in controlled conditions identical to the dilution method. Maintain the temperature at 20°C to follow the standard BOD measurement conditions.
• During incubation, aerobic bacteria in the water sample will consume oxygen and release carbon dioxide. This process will result in a decrease in the total amount of gas and, consequently, a drop in pressure.
• After the 5-day period, remove the sample from the incubator and take the final dissolved oxygen reading. This reading will indicate the amount of oxygen consumed by the bacteria.
• Calculate the BOD value using the formula: BOD5 = BOD mg/L = [(IDO - DO5) – seed correction] x dilution factor. This formula considers the initial and final dissolved oxygen levels, seed correction, and dilution factor.
• Interpret the BOD results: A higher BOD value indicates a higher level of organic pollution in the water sample. This information is essential for assessing the effectiveness of wastewater treatment processes and their impact on receiving waters.

It is important to note that traditional BOD measurement methods can be time-consuming and may not provide timely information for process control and improvement. However, recent advancements, such as Real Tech's BOD/COD meters and sensors, offer rapid and real-time BOD monitoring solutions. These innovative technologies utilize UV LEDs and multi-dimensional measurements to provide superior performance in wastewater process control and plant efficiency. Additionally, biosensors and combined sensor systems that incorporate fluorescence monitoring, such as tryptophan-like fluorescence (TLF), also offer promising alternatives for real-time BOD monitoring.

Frequently asked questions