The water body-specific advisories listed below are based on mercury and polychlorinated biphenyls (PCBs) in fish, lead and cadmium in shellfish, and perchlorate in all forms of aquatic life. Data from most long-term monitoring sites show an overall gradual decline in PCB levels. Although PCBs have not been produced in the U.S. since the 1970s, these compounds degrade very slowly and take decades to be completely removed from the environment. Kansas data show no clear increasing or declining trends in mercury concentrations in fish.
Kansas counties with current fish consumption advisories include Cherokee, Douglas, Johnson, Leavenworth, Reno, Sedgwick and Sumner counties.
Fish consumption advisories are formulated using EPA risk assessment methods. Cancer risk assessment is a method to determine the added increase in cancer levels in a human population if fish in the advisory areas are consumed regularly (one 8-ounce serving per week) over a 70-year period. Assessments that estimate the increased risk of cancer as greater than one in 100,000 persons are regarded as unacceptably high. Risk assessments for contaminants assessed as non-carcinogens (mercury, lead, cadmium) are based on 8-ounce serving size for adults and 4-ounce serving size for children nine to 18 years of age. For further technical information, go online to water.epa.gov/scitech/swguidance/fishshellfish/techguidance/technical_index.cfm.
Waterbody specific advisories
The Kansas agencies recommend not eating specified fish or aquatic life from the following locations:
- the Kansas River from Lawrence (below Bowersock Dam) downstream to Eudora at the confluence of the Wakarusa River (Douglas and Leavenworth counties) because of PCB levels in bottom-feeding fish (carp, blue catfish, channel catfish, flathead catfish, freshwater drum, bullheads, sturgeons, buffalos, carpsuckers and other sucker species);
- Horseshoe Lake located in units 22 and 23 of the Mined Lands Wildlife Area (Cherokee County) for all forms of aquatic life including fish because of perchlorate levels;
- Spring River from the confluence of Center Creek to the Kansas/Oklahoma border (Cherokee County) for shellfish (mussels, clams, and crayfish) because of lead and cadmium levels;
- Shoal Creek from the Missouri/Kansas border to Empire Lake (Cherokee County) for shellfish because of lead and cadmium levels;
- Cow Creek in Hutchinson and downstream to the confluence with the Arkansas River (Reno County) because of PCB levels in bottom-feeding fish; and
- Arkansas River from the Lincoln Street dam in Wichita downstream to the confluence with Cowskin Creek near Belle Plaine (Sedgwick and Sumner counties) because of PCB levels in bottom-feeding fish.
The agencies recommend restricting consumption of any species of fish from the following locations:
- Little Arkansas River from the Main Street Bridge immediately west of Valley Center to the confluence with the Arkansas River in Wichita (Sedgwick County) — limit of one 8-ounce serving per month for adults or one 4-ounce serving per month for children for all types of fish because of mercury and PCBs; and
- Blue River from U.S. 69 Highway to the Kansas/Missouri state line (Johnson County) — limit of one 8-ounce serving per week for adults or one 4-ounce serving per week for children for all types of fish because of mercury.
General advice for eating locally-caught fish
- women who are pregnant, may become pregnant, or are nursing and parents of children under twelve years of age may wish to consult with their physician about safe levels of fish consumption and mercury exposure. This sensitive group should restrict their total mercury intake as related to both supermarket fish and locally caught species. Kansas recommends that this sensitive group restrict consumption of locally caught fish, from waters not specifically covered by an advisory, to one 8 oz. meal per week for adults or one 4 oz. meal per week for children;
- people who regularly consume locally caught fish (more than one meal/week) can reduce their mercury intake by limiting their consumption of large predatory fish such as largemouth bass, walleye, and wiper. Larger/older fish of all types are more likely to have higher concentrations of mercury;
- available data comparing contaminant levels in whole fish versus fillets indicate that higher concentrations of PCBs and some other fat soluble contaminants are associated with whole fish. Kansas recommends avoiding the consumption of parts other than fillets, especially when eating bottom feeding fish; and
- consumers can reduce their ingestion of fat soluble contaminants such as PCBs by eating fillets only, trimming fat from fillets, and cooking in a manner in which fat drips away from the fillet.
Mercury in Kansas, monitoring efforts and results
Since 2004, KDHE and KDWP have been collecting additional fish tissue samples from both lakes and streams to evaluate mercury levels in Kansas fish. KDHE monitors the listed advisory sites, a number of large river sites, and randomly selected stream and river sites throughout the state each year. KDWP collects samples from the 17 largest and most heavily fished/harvested reservoirs every other year and from a number of randomly selected smaller public fishing lakes each year.
Kansas has decided to include new precautionary statements this year regarding mercury because monitoring results from some randomly selected streams and lakes exceed KDHE’s one-meal-per-week threshold. Advisories are normally based on three-year (six-sample) averages and examination of longer term trends. However, randomly-selected stream and lake sites are sampled only once unless randomly selected again and are used to interpret mercury levels geographically instead of on a site-by-site basis. Kansas lacks the resources to conduct follow-up investigations of all randomly-selected sites that exceed the above mentioned consumption thresholds. Follow-up studies are being conducted and will be conducted at locations where preliminary data indicates the occurrence of unusually high concentrations of mercury in fish.
Details of monitoring efforts and protocols may be found in the Fish Tissue Contaminant Monitoring Program Quality Assurance Monitoring Plan on the KDHE website at www.kdheks.gov/environment/qmp_2000/download/2007/FTCMP_QAMP.pdf .
Information on the Kansas Fish Tissue Contaminant Monitoring Program can be found at www.kdheks.gov/befs/fish_tissue_monitoring.htm . Advisories are also posted on the KDWP website, kdwp.state.ks.us/news/Fishing/Are-My-Fish-Safe-To-Eat .
For further information about mercury in fish, national advisories, and advisories in other states, visit the EPA website, www.epa.gov/fishadvisories/advice .