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Water is rarely pure. Whether it is water that enters our home for drinking and bathing, or dirty water flushed down the drain and returned back to the environment, there are hundreds of potential contaminants that remain in our water, even after purification efforts.
With nearly half of the population in the United States using at least one prescription drug in the past 30 days, and more than 20 percent using three or more, remnants of those drugs are commonly found in the water both exiting and entering our homes. And, while water treatment plants must meet federal regulations, most standards haven't been updated in 40 years. The result is a system that isn't able to routinely detect or completely remove pharmaceuticals and hundreds of other chemical compounds from drinking and wastewater.
Whether over-the-counter drugs or prescription medications, a portion of the medicines we ingest aren't used by our bodies and are excreted into our wastewater. Likewise, unused pharmaceuticals are often flushed down the toilet in whole form in order to keep out of the hands of others. While sewage systems are designed to remove harmful contaminants from our wastewater before being released back into the environment, studies have found anywhere from 20 percent to 90 percent of pharmaceuticals are typically removed from "influent," or sewage, depending on the treatment process used. The remaining chemicals are discharged as "effluent" and pumped back into local waterbodies.
Contamination from those wastewater treatment plants and leaking sewage and septic systems eventually ends up in larger rivers and lakes that are used as sources for drinking water. Treatment systems used for drinking water typically remove anywhere from 50 to 99 percent of pharmaceuticals from the water before reaching local homes. For instance, chlorine-based drinking water treatment plants — the most common in the United States — remove about 50 percent of pharmaceuticals. More advanced systems can remove more chemicals, with reverse-osmosis filters able to remove 99 percent of contaminants.
"Treatment doesn't remove all pharmaceuticals, and they aren't designed for that," said Laura Verona, who oversees the Michigan Department of Environmental Quality's (MDEQ) wastewater division in southeast Michigan. "They have looked for pharmaceuticals in water and have found them, but in low concentrations, it's nothing that should be cause for alarm."
The study of pharmaceuticals and other trace chemicals in water stemmed from research done in the late 1990s by the United States Geological Survey. By 2000, scientists had tested 139 streams in 30 different states for the presence of human and veterinary pharmaceuticals (including antibiotics), natural and synthetic hormones, detergent metabolites, plasticizers, insecticides and fire retardants. The results showed about 80 percent of streams tested had the presence of at least one of the contaminants, with half of the streams containing at least seven or more of the chemicals. The study, which was the first of its kind, led to a new classification of contaminants, considered "contaminants of emerging concern," and questions about how they impact waterways and sources for drinking water for millions of people....continued on page 2
Proper disposal of pharmaceuticals
Only a portion of the pharmaceuticals we use every day are actually absorbed by our bodies. The rest of our prescription and over-the-counter drugs end up being excreted and flushed down drain. However, experts say we can help reduce the amount of pharmaceuticals entering the environment and returning to our drinking water by practicing proper disposal techniques of unused drugs.
"We try to discourage flushing as much as we can," said Oakland County Water Resources Commissioner Jim Nash, who said he urges residents to take advantage of the sheriff's drug collection program.
Oakland County Sheriff Michael Bouchard said his department spearheaded Operation Medicine Cabinet in order to keep unused medications from being tossed in the trash or flushed down the toilet. The program, which operates under the authority of the federal Drug Enforcement Agency, allows people to anonymously drop off unused medications at sheriff office locations and local police departments. The pharmaceuticals are then incinerated, along with illegal drugs that are confiscated by the department's Narcotics Enforcement Team.
"That was many years ago," Bouchard said about the start of the program. "Now we expanded and there are only about 10 law enforcement agencies in Oakland County that don't participate. There is no real cost to them."
Drop-off locations include those at police departments in Birmingham, Bloomfield Township, Bloomfield Hills, Rochester, Rochester Hills. Additional locations include Auburn Hills, Beverly Hills, Clawson, Farmington Hills, Franklin, Holly, Huntington Woods, Keego Harbor, Madison Heights, Oak Park, Oxford, Royal Oak, Southfield, Troy, West Bloomfield and White Lake, as well as all sheriff's office substations.
"We take in tons. Literally, tons each year," Bouchard said. "The week we announced and launched the program, we had to go back to some locations and empty the cabinets the same week. We actually had people waiting at locations when we launched."
Septic systems: potential health threats
Municipal wastewater treatment plants designed to treat raw sewage from our homes must meet federal Clean Water Act requirements and be permitted by the National Pollutant Discharge Elimination System (NPDES) in order to operate. But tens of thousands of septic systems are currently operating at individual homes throughout Oakland County with little or no oversight from state, federal or local agencies.
"There are about 80,000 septic systems, and some estimate as many as 100,000, in Oakland County," said chief of environmental health Mark Hansell with the Oakland County Health Division. "They are predominantly in the north and west sections of the county. Areas that have been urbanized in the southeast section are less likely to have them."
Still, many homes in Bloomfield Township and the Rochester/Rochester Hills area lack sewer connections, instead relying on individual septic systems to dispose of sewage. The county health department is responsible for issuing permits for new systems and enforcing action to address leaking or failing septic systems.
"In general, a failing septic (system) can affect surface water quality and ground water quality, as well as the physical quality of having sewage on the ground if you're not near a lake or stream," Hansell said. "Sewage is known to carry many viruses and health hazards that require corrective action. It may also impact areas on drinking water wells."
Septic tanks are watertight containers that are buried beneath the ground. Wastewater from homes enter a septic tank, which holds the sewage to allow for solid waste to settle to the bottom and form sludge. Oil and greases float to the top of the tank and form scum. The process allows for partial decomposition of solids before being filtered through a second compartment and into a contained sanitary drain field where the water is further filtered through soils, removing more bacteria, viruses and nutrients.
Septic systems may fail due to an overflow of sewage or a variety of mechanical reasons, forcing raw sewage to leak out of the system. A failure may result in raw sewage pooling on the surface or entering groundwater, and local aquifers in nearby waterbodies. Residents on individual drinking water wells – of which there are about 100,000 in Oakland County – are particularly susceptible to septic contamination.
Hansell said only a small percentage of leaking septics are brought to the department's attention from complaints. And while the county's sanitary code requires septic owners to address leaks, the county is only aware of those brought to its attention.
"There is no program, currently, to require routine inspections of existing septics, either on a time frame or at the point of sale," Hansell said. "There is pending legislation at the state that would introduce that – there has been pending legislation statewide for many years."
Hansell said there aren't any current investigations underway regarding groundwater or surface water contamination caused by leaking septic systems.
The latest statewide efforts to require septic inspections (House Bill 5732) was introduced in June by state Rep. Julie Plawecki (D-Dearborn Heights). Under the proposed law, a baseline set of state septic regulations would be introduced to require an inspection is done when a home is sold, as well as when any construction permits are issued.
"Michigan has the weakest septic system regulation in the country and is desperately in need of reform on this very important issue," Plawecki said. "This legislation would implement the necessary regulatory framework, and is a great starting point to bring us in line with other states."