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Nitrogen or #nitrate contamination of drinking and surface water poses serious health risks, and can result from agricultural runoff in rivers. It is often associated with algal blooms as well. Also see the topic #phosphate. ## Nitrogen: Nitrates, Nitrite, Ammonia, & Ammonium (moved from the [Common Water Contaminants page](/common-water-contaminants)) Nitrates, Nitrite, Ammonia, & Ammonium are all "fixed" forms of nitrogen available to living organisms, and represent different stages of nitrogen in the [nitrogen cycle.]( Nitrogen is a major limiting nutrient in plant growth-- when nitrates occur in large quantities in water from fertilizers, manure, or sewage runoff, they can cause algal blooms that create dead zones. Nitrates have also been linked to increased risks of [cancer, and complications with a number of diseases, including asthma]( The EPA limits drinking water concentrations of Nitrates to 10mg/L or lower, however, health threats can occur even at those levels. Ammonia (NH3) and ammonium ion (NH4+) are related chemically by an acid / base reaction: `NH3 + H+ <=> NH4+` The equilibrium between ammonia and ammonium is pH dependent, with the two species being at the same concentration only under fairly alkaline conditions, pH = 9.25. At neutral pH, the concentration of free NH3 is less than 1% that of NH4+. Since this is the case, the concentration of ammonia is usually not significant and can be determined from the concentration of ammonium and the pH. **** ## Questions Questions can be either frequently asked questions, or "next step" challenges we're looking to solve. [questions:nitrogen] ## Activities [activities:nitrogen] ...

Author Comment Last activity Moderation
stevie "Yes! here's the report back on the event " | Read more » almost 4 years ago
belkinsa "Is the report ready? " | Read more » almost 4 years ago
DrJohnBarrett "I have more sophisticated instruments for water quality testing, if needed.. " | Read more » about 4 years ago
stevie "Also, we split up the kit before the workshop. We had the students divide into groups and rotate through the testing, so everyone was able to get h..." | Read more » about 4 years ago
stevie "Here's the page we put together to make a worksheet for students. It's from the materials in the book, but since we were doing this with 10 or so s..." | Read more » about 4 years ago
jpkearns "Our systems are simpler, lower in cost, and made from common local materials. Please get in touch if you have questions - " | Read more » over 6 years ago
emontoya57 "Very inspiring nice work!!! " | Read more » over 6 years ago
eustatic "very cool. good question regaring the water pressure control, I've often wondered that myself. " | Read more » over 6 years ago
liz "FYI Public Lab, additional informal conversation on this is also happening on the WeChat app -- let us know if you want to join there " | Read more » over 6 years ago
kgradow1 "Listed! " | Read more » over 6 years ago
liz "Thank you for this incredible documentation! Do you have a list of what you purchased from the Science Company? I bet other people would like to re..." | Read more » over 6 years ago
chemcarr "This is very interesting. I am also working towards this kind of analysis, and especially open source accessible, whether fabrication or software/k..." | Read more » over 7 years ago
Frikkie "Just noticed video1's name show nitrate. Its meant to be nitrite, sorry about that. " | Read more » over 7 years ago
Phil "This is wicked Stuff! Thanks for sharing! " | Read more » over 7 years ago
Frikkie "For anyone who wants to try out the excel tool, here is the video’s for the recordings I made for the colorimetric nitrite analysis, the EC and fla..." | Read more » over 7 years ago