Two streams flowing into a watershed serving Joplin contain antibiotics used to treat poultry and humans. That`s according to a two-year study by U-S Geological Survey. It focused on Clear Creek and Polk Creek, on the upper reaches of Shoal Creek in Barry County. There is significant chicken and turkey production in that southwest Missouri area. Officials suggest the sampling is biased. Clear Creek is downstream from the Monett sewage plant. Polk Creek runs through a number of poultry farms. It`s unclear whether the antibiotics influence water users downstream in the Shoal Creek watershed, which provides water to Joplin. Only limited research on the impact to public health has been done. Officials say the water detection technology only recently became available.