By John L. Moore
The Morning News
SPRINGDALE -- Researches found a lot more than just phosphorus recently in Northwest Arkansas streams and rivers.
While excess nutrients such as phosphorus and nitrogen have been hot topics in Northwest Arkansas watersheds for years, modern technology and research methods are allowing researchers to look at numerous organic chemicals that could not be detected at low level concentrations in past years, scientists said.
A study of area water released by the United States Geological Survey on Thursday found 42 different organic chemicals in area streams and rivers, including some antibiotics.
The study tested for 108 different compounds, including a wide variety of antibiotics, said Brian Haggard, a hydrologist with the United States Department of Agriculture who worked on the research with USGS scientists.
Researchers are increasingly concerned with how bacteria become resistant to antibiotics.
One concern is that low but chronic levels of antibiotics in the water and sediment of streams may make bacteria resistant to antibiotics, Haggard said.
People infected with antibiotic resistant strains can be harder to cure.
Some of the organic compounds, particularly plasticizers used in cosmetics and pharmaceuticals, can also disrupt endocrine systems in fish and other wildlife.
The endocrine disrupters can lead to reproductive and maturational problems in the fish, Haggard said.
But the report released Thursday from samples collected in 2004 is really just the first step, explained Joel Galloway, the lead researcher with USGS on the project.
"At this time, we don't know exactly what these results mean from a human health or stream health perspective," Galloway said. "The jury is still out on what low levels of organic compounds might do."
The study tested 17 different spots on streams in Benton and Washington County in March and April of 2004. An area along Mud Creek was also tested in August 2004.
Galloway said the USGS is conducting similar tests around the country.
One area was chosen in North Central Arkansas along a stream with almost no urban development as a reference point, Galloway said.
Sites were chosen above and below wastewater treatment plants on the streams to see if more organic compounds showed up below the plants after the treated wastewater was released into the streams.
Galloway said the research found that more organic chemicals were present downstream of the treatment plants, indicating some of the chemicals were probably coming from the treated wastewater.
Luanne Diffin, environmental services coordinator for Rogers Water Utilities, said the study was a good initial survey of organic compounds in Northwest Arkansas streams.
"We're very interested in looking at this more in the future and hope the USGS takes steps to secure funding along with other groups for further research," Diffin said.
The report found the most common organic compounds of the ones tested for were caffeine, phenol (found in disinfectants and some industrial processes), para-Cresol (disinfectant and wood preservative), and acetyl hexamethyl tetrahydro naphthalene (musk fragrance).
