Boron in Water
Boron in Water
Source of Boron in Water: The generic term “boron” refers to the boron content in boron-containing compounds and to elemental boron. In natural waters, boron exists primarily as boric acid and also borate ions. Naturally occurring boron is present in groundwater primarily as a result of leaching from rocks and soils containing borates and borosilicates. Fracking activities use borate salts that could contaminate groundwater. Boron compounds can leach into groundwater from pesticides, fertilizer runoff, sewage, and coal industries. Boron (Borax) is used in many household cleaning and laundry solutions. Highest boron concentration we have seen so far is from an irrigation well in the city of Cloverdale, California ZIP Code 95425 where the water analysis reported 120 mg/L of boron.
Effects of Boron in Water: Elemental boron and borates in water is non-toxic to humans and animals unless consumed in extremely high amounts. Boron is suspected but has not been directly proven of being a trace nutrient in humans. Large doses can cause nausea and vomiting. Chronic low-level oral exposure causes developmental defects in animal subjects. Because boron in drinking water is tasteless and invisible, water supplies should be tested to determine its level.
Health Canada has proposed a maximum acceptable concentration (MAC) of 2 mg/L (2000 μg/L) for total boron in drinking water based on treatment achievability.
Boron-contaminated irrigation water can cause a toxic response to plants grown hydroponically. Recommended boron concentration for commercial plant nutrition is less than 1 ppm.
How to Remove Boron: The best methods for removing Boron in drinking water are anion exchange treatment and/or customized high rejection reverse osmosis (RO) systems. RO membranes poorly reject boron at low pH since it mostly take the form of un-dissociated boric acid. As pH increases, boron takes on the form of borate, which is more easily rejected by reverse osmosis membranes. If anion exchange is used, upstream removal of iron/manganese is essential to minimize resin fouling potential.
For industrial water treatment, anion exchange resin in the strong base form (OH⁻) can be used to remove boron from water. The regeneration process requires hydrochloric acid or sulfuric acid for regeneration to remove the boron from the resin. This method is not recommended for residential water treatment applications.
High boron concentrations can be treated with custom made reverse osmosis systems designed with high rejection membranes and high pressure pumps (pre/post treatment may be needed). Contact us with your water analysis for a custom quote.
