Bacterial blooms and high nitrogen level in the local waters are not the only issues for those involved with water and sewer management.
Wastewater can contain a variety of medicines that are flushed down the toilet, such as ibuprofen, caffeine, and antibiotics as well as chemicals in personal care products can leach into the groundwater from wastewater.
“Contaminants of emerging concern are definitely a concern,” said Gerald Potamis, Falmouth wastewater superintendent. “There are few if any regulations on them and there are probably hundreds of them.”
The Cape is especially vulnerable to the flow of these chemicals into the groundwater because of the sandy soil and the high percentage of households, 85 percent, on septic systems where the wastewater is not treated.
George Heufelder, a member of Falmouth’s Board of Health and a director at the Barnstable County Department of Health and Environment, has been conducting research on shallow septic systems that may remove these contaminants of concern in wastewater better than standard systems.
“It appears in broad brush that the removal rate in soils-based shallow systems is at least two times that of a standard system and likely more,” Mr. Heufelder wrote by e-mail.
Research studies by the Silent Spring Institute detected various contaminants in local Cape Cod ponds and drinking water sources, however not in significantly high amounts.
“The highest levels we found were half of the lowest health-based guideline values,” Laurel Schaider, a research scientist at the Silent Spring Institute, said by phone.
Currently the EPA does not regulate these contaminants; thus there is no required testing of CECs in the drinking water. They do offer some health-based guidelines for certain compounds.
The institute, based in Newton, studies the link between chemicals in the environment and cancer. Mostly of concern are endocrine disruptors, which interfere with hormonal systems in both people and animals and are linked to cancer. The Cape is a study site of interest because breast cancer incidence in Barnstable County is about 21 percent above the national average, Dr. Schaider said.
In a 2008 study, the institute detected different compounds in three local ponds, which on the Cape are fed by groundwater. They found that ponds in more densely populated areas had higher levels of pharmaceuticals, such as antibiotics, epilepsy drugs, bipolar drugs, and hormones that can disrupt hormone systems in fish, Dr. Schaider said.
Dr. Schaider led another study in collaboration with nine Cape Cod public water suppliers published in 2013, where they looked for 92 chemicals in 20 public wells and water sources. They found emerging contaminants in 15 of the 20 public drinking water sources tested in Barnstable County.
The two most frequently found compounds were sulfamethoxadole, an antibiotic found in 60 percent of the wells and a perfluorosurfactant, used for stain resistance and non-stick coatings, and a known endocrine disruptor was found in 40 percent of the wells. Also the anti-seizure medicine, carbamazephrine, was found in 25 percent of the wells. Nine wells had more than one contaminant, with one having up to 12.
Even though the compounds are at low levels it is still worthwhile to continue study them. Scientists do not know the long-term effects of exposure or the mixing of these products in the environment, said Jared V. Goldstone, a toxicologist at the Woods Hole Oceanographic Institution and chairman of the Falmouth Board of Health.
“I don’t think that these compounds are an acute risk, but they may have an a cumulative effect,” Dr. Goldstone said.
Mr. Heufelder’s research led to shallow-horizon distribution systems, such as drip dispersal and shallow drainfield systems, which in some cases can remove close to 90 percent of certain emerging contaminants. They measure contaminants in the raw wastewater going into the system and then levels after the water passes through the system.
These units are a mere eight inches to one foot underground. In the upper soil there can be billions of bacteria per cubic centimeter because there is more access to air and nutrients in the root zone, Mr. Heufelder said.
The more diverse the bacteria, the more chance compounds in the wastewater will be broken down. If you go down four to five feet, the level of more traditional systems, there is less food and thus less bacteria.
“We are staying on top where everything happens,” Mr. Heufelder said.
With the construction of the new water filtration plant, CECs in the drinking water in Falmouth will not be a concern.
“The drinking water plant that they are putting in has the most advanced treatment,” Mr. Potamis said. “All the treatment processes will take care of what we know of today.”
However, the untreated wastewater entering the environment can still have an impact.
A 2007 study done at the Fisheries and Oceans Canada, Freshwater Institute showed that estrogens flowing into a lake feminized male fish and disrupted the females’ fertility resulting in a near extinction in the lake.
“Its not only habitat degradation, but also the possibility of affecting our food.” Dr. Goldstone said.