PFAS, or “forever chemicals,” are persistent pollutants linked to health risks like cancer and hormone disruption. PFAS detection and removal from water is challenging but essential for safety.
This blog explores the most effective methods for identifying and reducing PFAS contamination.
Table of Contents
PFAS & The Dangers
Per- and poly-fluoroalkyl substances (PFAS), often called “forever chemicals,” are synthetic chemicals that have a chain of linked carbon and fluorine atoms. Because the carbon-fluorine bond is one of the strongest, these chemicals do not degrade easily in the environment.
Due to their resistance, these chemicals have been used for decades in many consumer products (shown below). However, their persistence in the environment and accumulation in our bodies make them dangerous. As a result, PFAS detection and removal from water should be a priority.
Research suggests that high levels of PFAS can lead to certain health effects, including:
- Increased cholesterol levels
- Changes in liver enzymes
- Decreased vaccine response in children
- Increased risk of high blood pressure or pre-eclampsia in pregnant women
- Decreases in infant birth weights
- Increased risk of kidney & testicular cancer
⇓ Products that contain PFAS chemicals ⇓
How Do We Detect PFAS in Water?
PFAS detection and removal involves specialised laboratory methodologies. Since these chemicals are found in very low concentrations (often in parts per trillion or ppt), advanced techniques are needed to identify and quantify them accurately. The most common techniques to detect and measure PFAS levels in water utilise mass spectrometry.
Why it’s used:
This is the gold standard for PFAS detection due to its high sensitivity and ability to detect extremely low concentrations (down to parts per trillion).
Steps:
1) A water sample is passed through liquid chromatography (LC), which separates different chemicals based on how they interact with a liquid solvent.
2) Next, the separated chemicals enter the mass spectrometer (MS), which measures the weight (mass) of molecules to identify them.
3) The “tandem” part (MS/MS) means it uses two mass analysers for even better accuracy, helping detect specific PFAS compounds at very low levels (parts per trillion).
Advantages:
✔ Detects a wide range of PFAS compounds
✔ Provides precise and reliable results
✔ Used in regulatory testing worldwide
Why it’s used:
This method is more advanced than LC-MS/MS and can identify unknown PFAS compounds in addition to known ones.
Steps:
1) Like LC-MS/MS, HRMS first separates the chemicals using liquid chromatography (LC).
2) The difference is in the mass spectrometry step: HRMS can measure molecules with even higher precision, down to tiny differences in mass. This helps detect new or unknown PFAS compounds.
Advantages:
✔ Can detect unknown PFAS compounds
✔ Useful for research studies
Methods to Remove PFAS from Water
Water utilities use different methods to remove PFAS from drinking water. The main options include activated carbon, ion exchange, membrane filtration, and advanced oxidation processes (AOPs).
How it works: Activated carbon works by trapping PFAS molecules on its porous surface as water flows through.
Effectiveness: 80-90%. Granulated activated carbon (GAC) is generally more effective than powdered activated carbon (PAC).
Pros: Low cost & good for long-chain PFAS.
Cons: Not great for short-chain PFAS & needs frequent replacement.
How it works: IX resins are small beads with a positive or negative charge that attract and trap PFAS molecules.
Effectiveness: 77-99%.
Pros: Works well for short-chain PFAS & faster than activated carbon methods
Cons: Can be affected by other contaminants
How it works: Membrane filtration utilises high-pressure membranes with tiny pores to filter out contaminants, including PFAS. Reverse osmosis (RO) pores are smaller (0.0001 microns) than nanofiltration (NF) pores (0.001 microns).
Effectiveness: >99% (RO), 70-99% (NF).
Pros: Very effective & Removes all PFAS types
Cons: High energy use, costly & membranes can clog
How it works: AOPs use powerful chemicals (like ozone, hydrogen peroxide, or UV light) to break apart PFAS molecules. This method aims to destroy PFAS instead of just removing them.
Effectiveness: Up to 100% (for long-chain PFAS)
Pros: Can destroy PFAS instead of just removing
Cons: Expensive, still in development & may create unwanted byproducts
Conclusion for PFAS Detection and Removal
Ensuring our drinking water is free from PFAS is crucial to protect public health and the environment. We can address the challenges posed by these persistent chemicals through advanced PFAS detection and removal technologies. Ongoing research and investment in water treatment solutions are important to safeguard our water supply now and in the future.
At Southern Scientific Services, we are committed to providing comprehensive testing services to ensure the safety and quality of your drinking water. Our team of experts utilises state-of-the-art methods to reliably detect PFAS contamination, helping you maintain a healthy household.
