Tannin and lignin are naturally occurring chemical compounds, most frequently found in tea, coffee, chocolate, red wine, tree bark and where a large quantity of vegetation has decayed.
Tannin is also added to boiler water to help reduce scale formation inside the boiler. The EPA has no guidelines on expected levels in drinking water because there is no health risk associated with these compounds other than possibly a slight stimulant affect. Water that has lignin and tannin present has a faint yellow to brown color and may impart a slightly bitter taste. Water users may complain of yellow water, or dull dingy white clothes washed in the water, or a yellow/brown tint to anything that is cooked in the water. Although these chemicals may make the water aesthetically unpleasing, it has no health risks and can be removed easily with ion exchange resin treatments.
General testing is not specific for tannin or lignin, and unless tannin or lignin is definitely known to be present, the results will be reported in general terms as “PPM /hydroxylated aromatic compounds”
New this month! NOVA is offering Tannin and Lignin testing. Sample volume requirements are the same as a routine water test, with no hold time or refrigeration needed. The test can be run on drinking water and on boiler water. Cost is $30.00 and turnaround time of 3-5 working days.
