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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
GLwater "The Great Lakes basin has a few nonprofits as well as water treatment utilities working with gardening groups and some county extension Master Gard..." | Read more » over 2 years ago
joyofsoy "Shared this on the Public Lab Twitter and received this response: Measuring conductivity might be a simple proxy...— Jérôme Pellet (@jeromepellet)..." | Read more » over 2 years ago
Ag8n " My mistake, it chemiluminesces in the red, not the blue. Sorry about that. " | Read more » about 3 years ago
Ag8n " I've used ion chromatography(IC) to analyze for a number of ions, including nitrate and nitrite. The new instruments dedicated to IC are much bet..." | Read more » about 3 years ago
Ag8n "Warren got most of the problems with kjeldahl. Here are a few more. Kjeldahl testing takes some specialty glassware. It's not terribly hard to l..." | Read more » about 3 years ago
guolivar " All the way in New Zealand we also use Gradko for all our passive tubes needs. " | Read more » about 3 years ago
Bronwen "I did a little browsing and so far tthe Ormantine link @warren shared is the only US supplier that comes up quickly (will keep looking), and I have..." | Read more » about 3 years ago
warren " is in the US! Louise Francis mentioned the lab they work with gets them from Gradko -- https://www.grad..." | Read more » about 3 years ago
stevie "Yes! here's the report back on the event " | Read more » over 3 years ago
belkinsa "Is the report ready? " | Read more » over 3 years ago
WaterGeek "Great work and super useful for citizen's looking to track the quality and state of open water. We've been looking into something like this for dri..." | Read more » over 4 years ago
MadTinker "I would add the following: alkalinity, hardness, and perhaps ORP " | Read more » over 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
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 » about 7 years ago
Frikkie "Just noticed video1's name show nitrate. Its meant to be nitrite, sorry about that. " | Read more » about 7 years ago
Phil "This is wicked Stuff! Thanks for sharing! " | Read more » about 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 » about 7 years ago
cfastie "Guillaume, Moving the entrance slit farther from the grating might help. I found that the grating does not have to be angled so sharply when the gr..." | Read more » over 7 years ago
Guillaume123 "To Chris It will be relatively easy for me to take out the slit adjusting mechanism and move it further from the diffraction grating adjustment by..." | Read more » over 7 years ago
cfastie "Guillaume, That was a great idea to allow adjustments to the angle of the slit and grating. You should be able to find positions that produce very..." | Read more » over 7 years ago
Guillaume123 "Thanks idahoboy1941! I have looked at the Google entries. Many of them require payment, but one by WG Fastie is immediately interesting. I can eas..." | Read more » over 7 years ago