By Jim Ferretti
What’s the deal with bacteria?
Bacteria (along with soil erosion/runoff, and nutrients including nitrogen and phosphorus) are the leading types of pollution in our nation’s waterways. Pathogenic, or disease-causing microorganisms are associated with fecal waste and can cause a variety of diseases (typhoid, cholera, Cryptosporosis, etc) either through ingestion/contact with contaminated water or ingestion of shellfish. Not all bacteria are harmful (yogurt contains live bacteria cultures), but the presence of some indicator bacteria such as fecal coliforms and enterococci are a clue that potentially more harmful bacteria and viruses may be present in the water as well.
There are many different types of general pathogens that are dangerous to humans, including bacteria, viruses, and protozoa. Measuring all of these potential harmful organisms is not practical, cost effective, and measuring methods are often complicated. Instead, specific surrogate bacteria (i.e., Fecal Coliforms, E. coli, and Enterococcus sp) that can be cultured or detected easily and can be related to the risk of human illness are used as “indicator” bacteria, because their presence indicates that fecal contamination may have occurred. The higher the number of indicator bacteria would increase the risk of finding increasingly more harmful assemblages of more harmful types of organisms in the water.
Common sources of bacteria in surface waters are from combined sewers (which can overflow in a rainstorm and dump untreated sewage directly into our waters) and runoff of animal waste (including wild animal droppings) from farmland and city streets.
Indicator Bacteria and Citizen Science
During the summer months, bacteria concentrations are measured at least once a week at most of our New Jersey and New York bathing beaches. There are many other waterways that are used for boating, fishing and even swimming that are also susceptible to bacterial contamination. Citizen scientists offer a great resource to fill data gaps, produce data that will be usable by the states for assessment purposes, engage their community and raise awareness of potential environmental issues.
There are a few common types of laboratory tests that are performed to measure bacteria, such as growing them on a filter, growing them in test tubes, or growing them in special trays until a color endpoint is observed. Many of these tests are outside the technical expertise of many citizen science groups.
The EPA has been involved in Citizen Science since 1988 (formally called Volunteer Monitoring). The number of Citizen Science groups across the nation and particularly in our region has risen sharply in recent years. In an effort to empower citizens in their community through collection of high quality data, the EPA has recently been involved in a technical role in a Citizen Science Pathogen (Bacteria) Study involving two citizen science groups from New York (Bronx River Alliance and Sparkill Creek Watershed Alliance) and two from New Jersey (Friends of the Bonsal Preserve and the NY/NJ Baykeeper). The goal of this grant based program from the Harbor Estuary Program and administered through the New England Interstate Water Pollution Control Commission was to train citizen science groups, assist them in preparation of a Quality Assurance Project Plan (QAPP) or a plan that details all facets of their study, provide equipment and testing guidance manuals, perform on-site lab and field assessments, and provide a means to enter data into the national water quality data repository, WQX (formerly STORET).
Citizen Science Equipment Loan Program
Not only is this project important to the communities that are involved, this effort has provided the framework for future citizen science groups to conduct similar projects. Citizen scientists and communities may use the existing Quality Assurance Project Plan, Field and Lab Data Sheets, Excel spreadsheets for reporting, and technical guidance documents for sampling and analysis from this project that can be readily modified to fit their own pathogen monitoring program.
Another major hurdle for many citizen based science groups is the cost of equipment needed to collect the data. The cost for the lab equipment for a group to start a pathogen and water quality program similar to the one describe here is approximately $10,000. This cost is prohibitive to many citizen science groups so EPA is in the process of establishing an equipment loan program. The equipment loan program will offer citizen science organizations the opportunity to conduct water quality and/or pathogen studies with the benefit of borrowing on a short term basis (three to four months) lab equipment (incubators and sealers) and field equipment (water quality parameter meters and GPS units) plus the available technical documents (QAPP, testing guidance, and datasheets). Minus the cost of equipment, the actual per test cost for measuring bacteria is approximately $5-6 per sample.
So, prepare your QAPP, enroll in the equipment loan program, and have your group get out there and monitor!
About the Author: Jim Ferretti is a team leader for the Sanitary Chemistry and Biology Team for the Laboratory Branch in the EPA’s Division of Environmental Science and Assessment. He has a Master’s Degree in Environmental Science from Rutgers University and a BS Degree in Water Analysis Technology from California University of PA. Jim has a diversified background in environmental studies and biological laboratory testing. He has been employed at the EPA since 1990, starting out in the water program in headquarters and moving to New Jersey in 1992.