HOW PRODUCTS WERE EVALUATED:
How Products were Selected:
Products were selected to represent those commonly sold and/or available in the U.S. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers or direct sales. Products were not accepted directly from manufacturers.
- Microplastic particles (MPP): Water filter pitchers were evaluated under standard laboratory conditions for their ability to remove MPP from local potable tap water. Water filters were installed and flushed per each manufacturer's instructions. Water samples containing a known amount and size distribution of MPP were filtered through the filters and the filtrate was analyzed to determine the amounts and size distribution of MPP as well as opaque carbon particles. The amounts and size distribution was determined using an Olympus SZ61 stereomicroscope equipped with an OMAX Digital Camera and Image J software. MPP and opaque carbon particles were identified and quantified using Nile Red Tagging methodology described by Mason, et al. (2018).
- Heavy metals and ions: Water filter pitchers were evaluated under standard laboratory conditions for their ability to remove spiked amounts of lead, arsenic, cadmium, mercury, fluoride, chlorine and total dissolved solids from potable tap water using NSF/ANSI 42 and 53 — 2019 guidelines for Point of Use Non-regenerating filters. All spiked elements were added to bring the concentrations up to the Influent challenge concentrations (mg/L) listed in the NFS/ANSI 42 and 53. Water filters were installed and flushed per each manufacturer's instructions. Spiked water samples containing known amounts of heavy metals, ions and total dissolved solids were filtered through the filters and the filtrate was analyzed again to determine the amounts of arsenic cadmium and lead by inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAE).Mercury by cold vapor atomic absorption (CVAA) and chlorine and fluoride by ion chromatography. Total dissolved solids was determined by evaporation of a known amount of water sample at 180 degrees C before and after filtration.
To be "Approved" by Consumerlab.com, a product had to meet the following requirements:
- Reduce the amounts of lead, cadmium, arsenic, mercury, chlorine, fluoride and total dissolved solids to amounts listed on the filter's specifications sheet (provided with the product or separately from the manufacturer). (Approval is limited to those compounds included in the specifications).
- Reduce the amounts of microplastic particles to amounts listed on the filter's specifications sheet (provided with the product or separately from the manufacturer) and did not increase the total amount of microplastic particles.