By Judith Y. Aker

Nitrate deposition in our nation’s waterways is suspected of impacting human and wildlife health. Scientists are showing interest in nitrate impacts due to unexplained wildlife population declines and disappearances. Along with population declines are developmental changes in amphibians.

Researchers have noted that amphibians are good indicators of ecosystem change. Changes have been seen in the endocrine systems of amphibians which affect their ability to reproduce. If amphibian health is affected by nitrates, it is possible that human health may be also be impacted by nitrates.

Nitrate is found in all ecosystems in a natural state. It is also in most fertilizers, manure and liquid wastes from septic tanks. Nitrogen occurs naturally in soil and becomes nitrate through bacterial action. Humans influence nitrate deposition through land use practices such as farming, urban sprawl and urban development.

Agriculture contributes to nitrate production through use of pesticides, fertilizers, manure and concentrated livestock operations. Increased fertilizer usage has greatly escalated nitrogen deposition into the waterways. The mandated amount of nitrate allowable in water for public health safety is 10mg/L ppm (parts per million). Nitrate produces changes in metabolism, mortality and endocrine functions in wildlife species.

Nitrate impacts vary with different species of wildlife. Increased nitrate levels cause increased mortality of Chinook salmon and Rainbow trout. Amphibian risk of nitrate is highest in the egg and tadpole development stages. High nitrate toxicity has been shown to affect fish and amphibian eggs. Metabolic effects of nitrate speed up metamorphosis from tadpoles to toads as compared with those not impacted by nitrates.

These same toads exhibited unusual swimming patterns and deformations. It was also noticed that these creatures swim less and did not eat as much. The presence of nitrate in water and foods is suspect of causing some diseases and cancers in humans.

Nitrate consumption by pregnant women shows a probable connection to miscarriages and birth defects. Blue baby syndrome is brought about in infants through this contaminant’s consumption. Some researchers believe diseases such as Non-Hodgkin’s lymphoma, gastric cancer and hypertension are linked to nitrates in drinking water. Other suspect diseases include reduced sperm count, breast, testicular and prostate cancers. With all of this evidence, governmental legislation has been instituted to address the nitrate deposition issue.

Concern over the effects of nutrient deposition in Pennsylvania led to the enactment of the Pennsylvania Nutrient Management (Act 38 of 2005) Program.

The bill was enacted on July 6, 2005. This act contained stipulations regarding reviews of local ordinances and nutrient management. It is designed to protect and sustain agricultural operations and other farm products. This act also allows local government to protect the health, safety and well-being of its population.

Other agricultural regulations in this bill are the distance from a body of water that manure can be applied to a field and use of buffers. Nutrient management certification programs are to be developed by a certified individual under the auspices of the Chesapeake Bay Nonpoint Source Pollution Abatement Program and the United States Department of Agriculture’s Water Quality Improvement Projects Program.

In addition to government policies regarding nutrient issues, there are other methods that farmers may use to lessen nitrate effects on the environment. An effective way to reduce nutrient runoff is by planting a winter cover crop and spraying with an herbicide before the spring planting.

Plants take up the excess nitrogen, store it and when it is killed, the stored nutrients are put back into the soil. Another measure is by spreading manure on ground that has at least 25 percent crop residue or that already has an established cover crop. Nutrient management plans can be devised for individual farms through local county conservation districts.

A nutrient trading policy is another method introduced by Gov. Rendell. This strategy will help farmers, communities and industry meet and go beyond state and federal water quality goals. Pennsylvania is one of the first states to use this strategy for water quality. Market-based programs provide a means by which trading environmental credits help other areas meet their obligations or goals.

Judith Y. Aker has a degree in Georgraphy from Indiana University of Pennsylvania and is a member of the Indiana County PA Senior Environment Corps. She can be contact by sending email to: judith813@pa.net .

2/15/2008