Standard-exceeding levels of chemical found in water source
Levels of a contaminant detected higher than usual in a Lukins Brothers Water Company water system forced the company to use a substitute system and apply measures to address the contamination.
The chemical levels do not appear to be immediately concerning, but consumption of the current levels of tetrachloroethylene, also known as PCE, for “many years” could represent serious health risks to consumers, according to an Environmental Protection Agency (EPA) standards report.
Though it is not clear when the contamination occurred, the last test for PCE was performed in 2011, according to the 2014 Consumer Confidence report published by the water company.
“The impacts of limited exposure (ie, no more than three years) to tetrachloroethylene at the possible levels suggested by the utility’s public notice would not have meaningful effects on adults or children,” Margot Perez-Sullivan of the EPA stated in an email.
Water company officials shut off the contaminated water supply on July 11 immediately after receiving notice of the levels of PCE and restored service to its roughly 950 customers with an intertie neighboring water system, Jennifer Lukins of Lukins Brothers Water Company said. The water company sent notices to its customers about the PCE levels on Sept. 30.
Tests revealed that levels of the chemical were between 16 parts per billion and 43 parts per billion, roughly three-to-eight times the amount considered safe by the EPA.
The EPA considers 5 parts per billion to be the maximum contaminant level (MCL), and zero parts per billion to be the maximum contaminant level goal (MCLG).
Though there is currently no record or information suggesting that consumers of the water provided by the Lukins Brothers Water Company are at risk, if the water is consumed for many years at levels greater than the MCL, PCE is believed to increase the risk of cancer and can cause liver problems. Furthermore, studies have found a link to neurotoxic qualities.
According to an article published by The Washington Post, which cited a study published by the Environmental Health Journal on Sept. 30, children exposed to PCE as fetuses and toddlers are more likely to use drugs later in life. The toxin has also been linked to mental illness, an increased risk of breast cancer and some birth defects. It has been tied to anxiety, depression, and impairments in cognition, memory and attention.
It is, however, unclear at what level of exposure and for how many years health effects can become apparent.
The EPA 2012 Water Standards and Health Advisories report indicates that PCE consumed in levels exceeding 10 parts per billion over the span of a lifetime can produce health risks. For children 22 pounds and lighter, consuming water with levels of 2,000 parts per billion for 10 days could represent health risks. The daily drinking water consumption for the 22-pound child and 154-pound adult were assumed to be 1 liter per day and 2 liters per day, respectively.
According to Lukins, the water company followed all state and federal rules and regulations to address the problem. At this time, there is no need to look for an alternative water supply, Lukins said.
However, in cases where the PCE levels are considerably higher than those found in the Lukins Brothers water system, PCE has been linked to cause problems in pregnant women.
The study The Washington Post cited, titled “Prenatal drinking-water exposure to tetrachloroethylene and ischemic placental disease: a retrospective cohort study,” stated that pregnant women with high exposure to PCE were 2.4 times more likely to end with stillborn babies and 1.4 times more likely to experience placental abruption.
The sampled studied included women in Massachusetts who consumed the contaminated water for nearly 20 years with PCE levels in the thousands of parts per billion.
“It’s difficult to say whether or not our latest results apply to your setting because we found an effect only for high exposure levels which may be higher than those in your area. However, your levels are considerably higher than the current MCL and are definitely concerning,” co-author of the study, Ann Aschengrau, stated via email.
“It’s hard to translate our exposure metric to a simple water concentration because it took many other things into account but I think that our high exposure levels were much higher than your levels,” she added.
Though the water company conducted testing in accordance with the regulatory agencies, it is not yet clear when the contamination occurred or how, Lukins said.
Last year, the Lukins Brothers Water Company conducted about 85 tests for approximately 80 contaminants, but the last test for PCE was done in 2011. The results for those tests revealed that the PCE levels were under the 5 parts per billion MCL standard that the EPA sets.
The most common use of PCE is in the textile industry and as a component of aerosol dry-cleaning products, according to the EPA website.
The notice issued by the water company stated that the company aims to solve the issue by January 2016. The company is currently attempting to acquire grants to cover costs related to the contamination in an attempt to avoid passing costs to customers, Lukins said.
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