Nitrate and Nitrosatable Agrichemicals

Nitrate and Nitrosatable Agrichemicals

Atrazine and nitrate are the two most prevalent drinking water contaminants in Nebraska. 
Does exposure increase risk of adverse health outcomes? 

Wells sampled for atrazine (1977-2014). 916 positive of 4311 wells sampled        
Wells sampled for nitrate (1977-2014). 18,843 positive (> 2 mg/L) of 25,811 wells sampled

Nitrate is the most common chemical contaminant in the world’s aquifers. Atrazine is another widely used agrichemical and one of the most commonly detected pesticides in U.S. drinking water. These maps illustrate the distribution of wells that have tested positive for Atrazine and Nitrates.

Source: Quality-Assessed Agrichemical Contaminant Database for Nebraska Groundwater 

You can read more from the UNL’s Institute of Agriculture and Natural Resources.

Wells sampled. 60% Irrigation. 3% Commercial. 27% Domestic. 2% Public. 3% Livestock. 10% Monitoring.
Percent of wells positive for Nitrate contamination. Commercial 26%. Domestic 63%. Irrigation 75%. Public 57%. Monitoring 81%. Livestock 77%.
Percent wells positive for nitrate, atrazine and combination by well type (1977-2014)

New-Aaron, Moses; Meza, Jane L.; Shea, Patrick J.; and Rhoades, Martha, “Birth outcomes and water: A multidisciplinary study” (2018). Posters and Presentations: College of Public Health. 11

Adverse health outcomes from exposure to nitrate and atrazine in drinking water – is it plausible? 

When Atrazine and nitrate are present in an acidic environment, such as the human stomach, they can form a nitrosamine called NNAT(N-nitrosoatrazine). Many Nitrosamines are carcinogenic and cause birth defects in animals.

In human lymphocytes, nitrosamines can cause changes to the chromosomes at doses 1000 times lower than that of nitrate or atrazine alone. Suggesting a mixture of both is more toxic than exposure to just one contaminant alone.

Rhoades et al “Atrazine and Nitrate in Public Drinking Water Supplies and Non-Hodgkin Lymphoma in Nebraska, USA” Environ Health Insights 2013; 7: 15-27

Atrazine and nitrate in public drinking water supplies associated with non-Hodgkin lymphoma in Nebraska

  • NHL (Non-Hodgkin Lymphoma) risk is 2.5 times higher for subjects exposed to nitrate and atrazine in drinking water compared to subjects not exposed.
  • Indolent B-cell lymphoma risk – 3.5 times higher for subjects exposed to nitrate and atrazine in drinking water compared to subjects not exposed.
  • Hypothesis:  Increased NHL risk due to in vivo formation of NNAT causing chromosomal mutations during metabolism leads to the development of cancer.

Rhoades et al “Atrazine and Nitrate in Public Drinking Water Supplies and Non-Hodgkin Lymphoma in Nebraska, USA” Environ Health Insights 2013; 7: 15-27