PFAS Test Results
October 2, 2024
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in October 2024 the sum of the six compounds is 4.16 ppt.
Click here for the current PFAS results
Click HERE for 2024 PFAS results
Click HERE for 2023 PFAS results
Click HERE for 2022 PFAS results
July 10, 2024
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in July 2024 the sum of the six compounds is 1.80 ppt.
April 25, 2024
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in April 2024 the sum of the six compounds is ND ppt.
January 19, 2024
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in November 2023 the sum of the six compounds is 6.3 ppt.
August 29, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in July 2023 the sum of the six compounds is 2.1 ppt.
July 24, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in April 2023 the sum of the six compounds is 2.4 ppt.
April 18, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in March 2023 the sum of the six compounds is 2.7 ppt.
March 14, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in February 2023 the sum of the six compounds is 3.2 ppt.
February 9, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in January 2023 the sum of the six compounds is ND ppt.
January 10, 2023
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in December 2022 the sum of the six compounds is ND ppt.
December 19, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in November 2022 the sum of the six compounds is 3.4 ppt.
September 19, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in August 2022 the sum of the six compounds is 17.1 ppt.
August 2, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in July 2022 the sum of the six compounds is 16.2 ppt.
July 7, 2022
What is the US Environmental Protection Agency’s (EPA) Interim Health Advisory (HA) Level and what does it mean?
It can be a lengthy process to set drinking water regulations. With science, there’s no such thing as zero, so research is important to determine an acceptable risk level for public health. A health advisory level is commonly a first step in EPA developing a regulation.
On June 15, 2022, the EPA set new Interim Health Advisory Levels for PFOA at 0.004 parts per trillion (ppt) and 0.02 parts per trillion (ppt) for PFOS. These are microscopic levels, trace amounts. For a visual perspective, 1 part per trillion is equal to 1 drop in 20 olympic sized swimming pools. These new health advisories are also below current reliable detection abilities of scientific equipment (Scientists can currently detect PFAS compounds down to 2 parts per trillion).
EPA Health advisories are not enforceable and are not regulations. Instead, the advisories are interim guidance before EPA develops a formal regulation. The health advisory level is the minimum concentration of a compound which may present health risks to an individual over a lifetime of exposure. Because there is uncertainty of the health effects associated with long-term exposure to compounds, EPA sets lower health advisories. Sometimes, the advisory is lower than current analytical methods can detect.
EPA first issued a health advisory level for PFOA and PFOS in 2016 at 70 parts per trillion. Because of further research and as EPA determines its regulatory approach, it has created a lower health advisory from 2016. The intend from the EPA is to propose a draft regulation for PFAS Compounds by the end of 2022 for public comment and review and release the final PFAS Regulation by the end of 2023. It should be noted that the EPA regulatory schedule for PFAS is very aggressive and will likely take quite a bit longer to achieve.
What does Cambridge need to do now?
The Cambridge Water Department (CWD) will continue our work to replace the Granular Activated Carbon (GAC) Filter Media and wait to hear from Mass DEP as they now will need to review the EPAHA.
The MassDEP has published the following statement:
On June 15, 2022, EPA released four drinking water health advisories for PFAS contaminants.
At this time, MassDEP is working to review the new EPA Interim Health Advisories and will determine next steps based upon that review. Massachusetts is home to some of strictest PFAS standards in the country, strengthened by the Baker-Polito Administration promulgation and implementation of nation-leading rules for drinking water systems and cleanups of contaminated sites, and investment of substantial funding to assist communities as they address PFAS contamination in drinking water systems.
For more information about EPA Health Advisories for PFAS seeDrinking Water Health Advisories for PFAS Fact Sheet for Communities and Questions and Answers: Drinking Water Health Advisories for PFOA, PFOS, GenX, PFBS FAQs.
Additional information on the MassDEP public drinking water standard:
310 CMR 22.00: The Massachusetts Drinking Water Regulations
Per- and Polyfluoroalkyl Substances (PFAS) Drinking Water Regulations Quick Reference Guide
Technical Support Document: Per- and Polyfluoroalkyl Substances (PFAS): An Updated Subgroup Approach to Groundwater and Drinking Water Values
June 22, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in May 2022 the sum of the six compounds is 16.01 ppt.
Click here for the current PFAS results
Click here for 2022 PFAS results
Click HERE for 2021 PFAS results
April 12, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in April 2022 the sum of the six compounds is 15.00 ppt.
March 16, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in March 2022 the sum of the six compounds is 13.3 ppt.
February 15, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in February 2022 the sum of the six compounds is 11.7 ppt.
February 1, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in January 2022 the sum of the six compounds is 13.6 ppt.
January 11, 2022
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in December 2021 the sum of the six compounds is 14.8 ppt.
November 8, 2021
To Cambridge Water Customers:
The following information is being provided in order to give an update on the Cambridge Water Department’s monitoring program for Per and Polyfluoroalkyl Substances (PFAS) contaminants.
IMPORTANT – PLEASE NOTE:
It is important to note that the City’s Water Supply is in compliance with the Massachusetts Department of Environmental Protection’s (MassDEP) standards regarding PFAS and that this information is being provided because after many months of sampling, the City experienced one reading in September, 2021 that was just slightly above 20 ppt (@ 20.7 ppt). All previous readings, and the most recent reading in October 2021, which is currently undergoing review by MassDEP, have been below 20 ppt, and the City has consistently been in compliance with the PFAS6 Maximum Contaminant Level (MCL) published by MassDEP since we started our PFAS monitoring program in August 2019.
Like many public water supply operators, the City has been aware of the emergence of PFAS as contaminants of concern in recent years. The MassDEP standard for the level of PFAS in public drinking water is 20 nanograms per liter (ng/l), or 20 parts per trillion (ppt) for six specific compounds called “PFAS6”. The Water Department has been in compliance with the MassDEP regulations at all times since we started monitoring for PFAS in August 2019, and has also been proactively monitoring for PFAS in our water supply reservoirs since that time (Hobbs Brook, Stony Brook and Fresh Pond) to stay on top of this emerging issue.
While the levels of PFAS we have found in our monitoring program since August 2019 have been below state standards and federal guidelines, the Water Department has been aggressively evaluating how to reduce these levels to below 10 ppt since that time. This level is one-half of the state standard of 20 ppt.
The MassDEP promulgated a new regulation on October 2, 2020 for the six PFAS compounds designated as PFAS6. Within about a year from when this new regulation was adopted, the City tested and obtained approval from the MassDEP to replace the Granular Activated Carbon (GAC) filter media in our water purification facility to strengthen our ability to remove PFAS from the water supply. We are in the process of completing the technical specifications to bid out and replace our filter media. We expect that this will be completed in the spring of 2022. When the filter media is replaced, it is anticipated that our PFAS levels will be lower and will reliably and consistently be below 10 ppt.
Please see the attached Public Education Materials recommended by the MassDEP for more detailed information, and feel free to contact us if you have any questions or would like any additional information.
Sam Corda
Managing Director
Cambridge Water Department
Important Public Education Materials about Per- and Polyfluoroalkyl Substances (PFAS)
This material contains important information about your drinking water.
Please translate it, speak with someone who understands it
or ask the contact listed below for a translation.
What is the Current Regulatory Compliance Status?
Our Public Water Supply is in compliance with the MassDEP Published PFAS regulations, which went into effect beginning October 2, 2020, requiring that each quarterly average be at or under the Maximum Contaminant Level (MCL) of 20 ppt for the sum of six PFAS compounds.
The six PFAS compounds are: 1) PFOS: perfluorooctanesulfonic acid; 2) PFOA: perfluorooctanoic acid; 3) PFNA: perfluorononanoic acid; 4) PFHxS: perfluorohexanesulfonic acid; 5) PFHpA: perfluoroheptanoic acid and 6) PFDA: perfluorodecanoic acid. MassDEP abbreviates this set of six PFAS compounds as “PFAS6.”
What PFAS Levels Have Been Detected in Our Drinking Water?
A summary of the PFAS6 monitoring results, since January 1, 2021, are provided below - all results are in parts per trillion* (ppt):
*For reference, 1 part per trillion (ppt) is a microscopic measurement for substances in the water and is equivalent to a single drop of water in the combined water volume of 20 Olympic size swimming pools.
1 = PFAS results are currently undergoing quality assurance/quality control review by MassDEP as required for all PFAS sample results.
Some people who drink water containing PFAS6 in excess of the MCL may experience certain adverse effects. These could include effects on the liver, blood, immune system, thyroid, and fetal development. These PFAS6 may also elevate the risk of certain cancers.
For more information on PFAS, see the links below.
(See PFAS Quarterly attachment)
(See PFAS Historical attachment)
What should I do?
For Consumers in a sensitive subgroup (pregnant or nursing women, infants and people diagnosed by their health care provider to have a compromised immune system)
- are advised not to consume, drink, or cook with water when the level of PFAS6 is above the 20 ppt.
- are advised to use bottled water for drinking and cooking of foods that absorb water (like pasta).
- For infant formula, use bottled water or use formula that does not require adding water.
- Bottled water should only be used if it has been tested.The Massachusetts Department of Public Health requires companies licensed to sell or distribute bottled water or carbonated non-alcoholic beverages to test for PFAS. See https://www.mass.gov/info-details/water-quality-standards-for-bottled-water-in-massachusetts#list-of-bottlers-
For all other consumers not in a sensitive subgroup
- If you are not in a sensitive subgroup, you may continue to consume the water because the 20 ng/L value is applicable to a lifetime consuming the water and shorter duration exposures present less risk.
- If you have specific health concerns regarding your past exposure, you should see the Centers for Disease Control and Prevention’s link below and consult a health professional, such as your doctor.
Steps you can take to reduce your intake - Consider taking the following steps while actions are being implemented to address this issue:
- For older children and adults (not in a sensitive subgroup), the 20 ng/L value is applicable to a lifetime of consuming the water. For these groups, shorter duration exposures present less risk. However, if you are concerned about your exposure while steps are being taken to assess and lower the PFAS6 concentration in the drinking water, use of bottled waterwill reduce your exposure.
- Home water treatment systems that are certified to remove PFAS by an independent testing group such as NSF, UL, or the Water Quality Association may be effective in treating the water. These may include point of entry systems, which treat all the water entering a home, or point of use devices, which treat water where it is used, such as at a faucet. For information on selecting home treatment devices that are effective in treating the water for PFAS6 see the weblinks below.
- In most situations, the water can be safely used for washing foods, brushing teeth, bathing, and showering.
Please note: Boiling the water will not destroy PFAS6 and will somewhat increase its level due to evaporation of some of the water.
What are PFAS?
PFAS are fluorinated organic chemicals that are contained in: consumer products that are resistant to water, grease, or stains; nonstick cookware; waterproof clothing, carpeting and furniture upholstery; water-resistant food wrappers and containers, firefighting foams and many other products. The Cambridge Fire Department does not use firefighting foam with PFAS. Very low levels of human-made PFAS compounds are commonly found in drinking water supplies throughout the United States without a known source of contamination. Most uses of PFAS compounds were phased out 10 to 15 years ago and replaced with other compounds that are thought to pose fewer health risks. But because PFAS were used in so many consumer products and they degrade slowly, if at all, most people have been exposed to them.
The PFAS family of chemicals are often referred to as “forever chemicals” due to the fact they degrade very slowly in the environment.
What is the City of Cambridge Water Department Doing About PFAS?
The Water Department has been aggressively pursuing steps to monitor for PFAS and to implement measures to address the levels of PFAS, including replacing the filter media (the material in the filters) at the City’s treatment plant in order to reduce the PFAS levels detected. Our accomplishments so far: 1) appropriated $1.4M (FY21 Budget) to replace the filter media; 2) obtained approval from the Massachusetts Department of Environmental Protection (MassDEP) to perform a Pilot Study to select the best filter media; 3) Completed the Pilot Study (November 2020 – July 2021); 4) Submitted a report, with the recommended filter media, to MassDEP for approval; 5) Obtained MassDEP approval to replace the filter media on October 18, 2021; 6) Initiated the development of the bid specifications to purchase and install the recommended filter media.
Our next steps: a) complete the bid specifications; b) put the purchase and replacement of the filter media out to bid; c) review and award the installation contract; d) replace the filter media. The anticipated completion date is Spring 2022.
How are People Exposed to PFAS?
While consumer products and food are the largest source of exposure to these chemicals for most people, drinking water can be an additional source of exposure in communities where these chemicals have contaminated water supplies. Such contamination is typically localized and associated with a specific facility, for example, an airfield where they were used for firefighting or a facility where PFAS were produced or used. As is the situation with other public water supplies, very low levels of human-made PFAS compounds have been detected in our drinking water reservoirs. To date, we have not identified any specific source of contamination, as PFAS degrade very slowly and are commonly found in groundwater and soils.
What are the Health Advisory and Regulatory Levels for PFAS?
In 2016, the EPA published a lifetime Health Advisory (HA) of 70 parts per trillion (ppt) for the combination of two PFAS compounds – PFOS and PFOA – in drinking water. In 2021, EPA has taken action to collect new data needed to improve understanding of PFAS and to begin to develop a national primary drinking water regulation for PFAS.
In December 2019, MassDEP amended Massachusetts hazardous waste cleanup regulations (the Massachusetts Contingency Plan or “MCP”) to add Reportable Concentrations and cleanup standards for soil and groundwater to address sites contaminated with PFAS. The new standard for groundwater that is currently used (or could be used) for drinking water is 20 ppt for 6 PFAS compounds, which is consistent with the new drinking water regulatory limit described below.
In October 2020, MassDEP finalized a drinking water standard for public water systems, known as a Maximum Contaminant Level, for PFAS6. A Maximum Contaminant Level or MCL means the maximum permissible level of a contaminant in water which is delivered to any user of a public water system. Information on this effort, including information on stakeholder meetings, can be found at https://www.mass.gov/lists/development-of-a-pfas-drinking-water-standard-mcl. The MCL is 20 ppt individually or for the sum of the concentrations of six specific PFAS compounds, based on a quarterly average (PFOS, PFOA, PFNA, PFHxS, PFHpA, and PFDA) in drinking water. Some people who drink water containing PFAS in excess of the MCL may experience certain adverse effects. These could include effects on the liver, blood, immune system, thyroid, and fetal development. These PFAS6 may also elevate the risk of certain cancers. MassDEP and the CDC both note that more research is needed and is ongoing, and it is important to remember that consuming water with PFAS6 above the MCL quarterly average does not mean adverse effects will occur.
If You Have Additional Concerns, What Can You Do?
There is still much that we do not know about PFAS and its impact on human health. As of now, the MassDEP advises consumers in sensitive subgroups avoid consuming water with PFAS6 that is not in compliance with the 20 ppt quarterly average. It is important to note that the Cambridge Water Supply is currently in compliance. Although not required based on the sampling results the City has completed, if you are a sensitive consumer (pregnant women, nursing mothers and infants or people diagnosed by their health care provider to have a compromised immune system) you can further minimize your exposure by using bottled water that has been tested for PFAS for drinking, making infant formula, and cooking foods that absorb water (like pasta). Alternatively, you can use a home water treatment system that is certified to remove PFAS by an independent testing group such as NSF International, Underwriters Laboratories, Water Quality Association, or the CSA Group. See the MassDEP PFAS webpage for more information: https://www.mass.gov/info-details/per-and-polyfluoroalkyl-substances-pfas.
Boiling water will not destroy PFAS and will somewhat increase their levels due to evaporation of some of the water.
As PFAS compounds are not well absorbed through the skin, you may safely use the water for bathing and showering. If you are concerned about your exposure, even though the risk is very low, you may use bottled water for brushing your teeth and cleaning items like dentures, pacifiers, fruits and vegetables.
If you have specific health concerns regarding your exposure, you may want to consult a health professional, such as your doctor.
Where Can You Get More Information?
For more information on the City of Cambridge’s proactive approach, please contact:
Julie Greenwood-Torelli - Director of Water Operations
Krystyna McInally: 617-349-4780; kmcinally@cambridgema.gov
Sam Corda: 617-349-4792; scorda@cambridgema.gov
Cambridge Water Department, 250 Fresh Pond Parkway, Cambridge, MA 02138
617-349-4700; CWD@cambridgema.gov
PWS Name: City of Cambridge Water Department; PWS ID#: 3049000
Date distributed: November 2021
You may also find more information on PFAS from the following sources:
MassDEP Fact Sheet – PFAS in Drinking Water: Questions and Answers for Consumers
https://www.mass.gov/doc/massdep-fact-sheet-pfas-in-drinking-water-questions-and-answers-for-consumers/download
· MassDEP Fact Sheet - Home Water Treatment Devices - Point of Entry and Point of Use Drinking Water Treatment – (https://www.mass.gov/service-details/home-water-treatment-devices-point-of-entry-and-point-of-use-drinking-water)
· Massachusetts Department of Public Health information about PFAS in Drinking Water - https://www.mass.gov/service-details/per-and-polyfluoroalkyl-substances-pfas-in-drinking-water
USEPA’s Drinking Water Health Advisories can be found at: https://www.epa.gov/ground-water-and-drinking-water/drinking-water-health-advisories-pfoa-and-pfos
The Centers for Disease Control (CDC) and Prevention’s Public Health Statement for PFOS and PFOA can be found at: https://www.atsdr.cdc.gov/pfas/index.html
For additional information on possible health effects, you may contact the Massachusetts Department of Environmental Protection, Office of Research and Standards, at 617-556-1165.
Please share this information with other people who drink this water, especially those who may not have seen this notice (for example, people in apartments, nursing homes, schools, and businesses).
please click here for a PDF version of this notice
HISTORIC DATA
September 9, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in August 2021 the sum of the six compounds is 18.5 ppt.
Click here for the current PFAS results
Click here for historic PFAS results
On October 2, 2020 MassDEP Published its PFAS regulations with the MCL of 20 ng/L for the sum of PFAS6. This regulation went into affect beginning January 1, 2021 for Cambridge.
Please use the following link to see the MassDEP PFAS Drinking Water Regulation Quick Reference Guide.
https://www.mass.gov/doc/per-and-polyfluoroalkyl-substances-pfas-drinking-water-regulations-quick-reference-guide/download
The City is continuing to pursue an upgrade of the Granular Activated Carbon (GAC) used as a fine filter for our finished drinking water. Replacing this filtering media is expected to reduce PFAS by a significant amount, likely 50% or more once installed. The process of selecting an appropriate GAC product has begun. This process includes the following steps:
- Submittal and MassDEP approval of a bench scale testing plan to select the best GAC filter media to reduce the PFAS levels in our water – Approved
- Preform the bench scale testing of various GAC media and make recommendation to MassDEP of a specific media for use in our treatment plant.- In Process
- Bid out and select a vendor to replace the filter media with the MassDEP approved GAC product.
- Replace our filter media.
Our goal is to have the media replaced by the end of calendar year 2021.
April 26, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in April 2021 the sum of the six compounds is 17.1 ppt.
April 14, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in March 2021 the sum of the six compounds is 15.8 ppt.
March 22, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing PFAS testing in February 2021 the sum of the six compounds is 11.3 ppt.
February 9, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing our eighth round of PFAS testing in January 2021 the sum of the six compounds is 12.2 ppt.
January 12, 2021
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing our seventh round of PFAS testing in December 2020 the quarterly average of the compounds remains at 16.8 ppt.
December 15, 2020
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing our sixth round of PFAS testing in November 2020 the quarterly average of the compounds remains is 16.8 ppt.
October 8, 2020
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds in our finished water being delivered to customers. After performing our fifth round of PFAS testing in September 2020 the quarterly average of the compounds remains at 17.0 ppt.
On October 2, 2020 MassDEP Published its PFAS regulations with the MCL of 20 ng/L for the sum of PFAS6. This regulation will be in affect beginning January 1, 2021 for Cambridge.
Please use the following link to see the MassDEP PFAS Drinking Water Regulation Quick Reference Guide.
https://www.mass.gov/doc/per-and-polyfluoroalkyl-substances-pfas-drinking-water-regulations-quick-reference-guide/download
The City is continuing to pursue an upgrade of the Granular Activated Carbon (GAC) used as a fine filter for our finished drinking water. Replacing this filtering media is expected to reduce PFAS by a significant amount, likely 50% or more once installed. The process of selecting an appropriate GAC product has begun. This process includes the following steps:
- Submittal and MassDEP approval of a bench scale testing plan to select the best GAC filter media to reduce the PFAS levels in our water – Approved
- Preform the bench scale testing of various GAC media and make recommendation to MassDEP of a specific media for use in our treatment plant.- In Process
- Bid out and select a vendor to replace the filter media with the MassDEP approved GAC product.
- Replace our filter media.
Our goal is to have the media replaced by the end of calendar year 2020.
In parallel we are looking at the options of determining the source/s of the PFAS compounds to look at any possible shorter-term options to reduce the level of the PFAS compounds in our water. Unfortunately, the first set of PFAS testing from each of our three (3) reservoirs has not shown any variations where “blending” our water from Stony Brook vs. Fresh Pond will make any significant difference in our PFAS levels.
We have also reviewed the possibility of “blending” Cambridge water with that of the MWRA and this is currently not technically feasible.
November 8, 2019
The Cambridge Water Department (CWD) detected the total of the six (6) PFAS compounds, as proposed in the Massachusetts Contingency Plan (MCP), in our finished water being delivered to customers to be confirmed at 19.9 ppt.
As a result of our voluntary testing for PFAS we have sent the following letter to the Cambridge City Council and Water Board.
Dear City Councilor/Water Board Member:
Massachusetts Department of Environmental Protection (MassDEP) has recently begun a statewide initiative to test drinking water from community water supplies in order to identify a newly prioritized family of chemicals called Per- and Polyfluoroalkyl Substances (PFAS). As of June 2018 MassDEP adopted minimal safe levels in local drinking water, based on US EPA risk-based standards, of 70 parts per trillion (ppt) when combining the measured concentration of 6 critical members of this class of chemicals. This standard (70 ppt when all 6 target PFAS compounds are combined) is intended to protect even the most sensitive users, including pregnant women, from adverse health effects, assuming a lifetime of regular tap water consumption.
The combined concentration of these 6 PFAS compounds detected in Cambridge water (19.9 parts per trillion) is well below the current MassDEP and EPA Health Advisory Level for all users (70 parts per trillion) and just below the MassDEP advisory range for public notification (20-70 parts per trillion). These results for Cambridge water are also below the California Water Resource Council Board’s Notification Level. It is important to emphasize that the levels observed over duplicate testing rounds are well below the most sensitive and protective risk-based standards used by the US EPA and the Agency for Toxic Diseases Registry (ATSDR). Keeping with our history of transparent communications with the community, we have voluntarily chosen to follow MassDEP’s communications guidance proposed for water systems that do fall within the 20-70 ppt range. For this reason, we are sharing these results with City Council, the Cambridge Water Board and all Cambridge households by posting a summary of test results with explanatory narrative on our website and in the June 2020 annual Water Quality Report.
The City is actively pursuing an upgrade of the granular activated carbon (GAC) used as a fine filter for finished drinking water. Replacing this filtering media is expected to reduce PFAS by a significant amount, likely 50% or more once installed, and would confer co-benefits by reducing the presence of other possible contaminants as well. The process of selecting an appropriate GAC product will begin in the next few weeks. The GAC upgrade, including MassDEP regulatory review, is expected to be completed later in 2020.
Cambridge Water Department is committed to take the following actions to address the presence of PFAS in our water supply:
- continue to test for PFAS compounds on a quarterly basis,
- evaluate the relative contribution of PFAS to our water system from all three sources (Hobbs Brook, Stony Brook and Fresh Pond Reservoirs),
- run bench scale tests to verify PFAS removal efficiency and duration by comparing several Granular Activated Carbon (GAC) products, and
- complete the replacement of the Granular Activated Carbon in the Cambridge Water Department’s six filters over the course of the next 12 months.
It is common to find very low levels of man-made PFAS compounds in drinking water supplies, since they are known to degrade very slowly and are commonly found in groundwater and soils surrounding drinking water sources. For context it is also important to note that many PFAS compounds have previously been used in common products such as stain repellants, nonstick cookware, waterproof clothing, water-resistant food wrappers and containers, and many other household products. PFAS may also be found in areas impacted by prior use of industrial products such as fire-suppressing foams. Most uses of PFAS compounds were phased-out 10-15 years ago, replaced with other compounds that are thought to pose fewer health risks.
Given the emerging concerns about PFAS across the country, the City of Cambridge is electing to adopt a thorough communication approach to inform the public about the status of their drinking water and efforts we are proactively taking to ensure the safety of our water supply. You can read more about Per- and Polyfluoroalkyl Substances (PFAS) on the Cambridge Water Department or MassDEP website.