Key points
- Levels of some PFAS in the blood of Westfield, MA, residents were up to four times higher than national levels.
- Elevated blood levels may be linked with past drinking water contamination.
- Some demographic and lifestyle characteristics were linked with higher PFAS blood levels.
Background
In 2019, the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR) conducted exposure assessments (EAs) focused in communities that were known to have PFAS in their drinking water. The EA sites are also near current or former military bases.
The EAs provide information to communities about levels of PFAS in their bodies. EAs can provide guidance to help people reduce or stop PFAS exposure.
This PFAS exposure assessment report for the area in Hampden County, MA, near the Barnes Air National Guard Base site was released on November 18, 2021. The complete report is available.
CDC/ATSDR sent the individual test results to participants and released summary results to the community in May 2020.
Why the Westfield site was selected
Why did we select Westfield?
When selecting EA sites, ATSDR considered the extent of PFOA and PFOS contamination in drinking water supplies. It also considered:
- The duration that exposure may have occurred.
- The number of potentially affected residents.
Westfield, MA, was identified as having PFAS drinking water contamination from use of products like aqueous film forming foam (AFFF). As early as the 1980s, the Barnes Air National Guard Base used AFFF containing PFAS for its firefighter training. Over time, the PFAS from the AFFF entered the ground and moved into the groundwater to offsite locations. It then affected nearby municipal wells.
PFAS were first detected in the Westfield water system in 2013. Over the next several years, the City of Westfield took actions to reduce PFAS levels in water supplies. These actions included:
- Removing drinking water supply wells from service.
- Temporary water restrictions on all non-essential water use.
Municipal drinking water testing in 2016 for a set of PFAS showed that levels met the U.S. Environmental Protection Agency's (EPA) 2016 Health Advisory (HA). Based on the information we reviewed as part of the EA, the public drinking water supply in Westfield continues to meet this HA.
Sampling area
Timeline
Information session
Meeting date: 07/23/19
Recruitment begins
Letters sent following the information session
Letters sent 07/23/19
Phone calls start 07/29/19Field work/sample collection
Began: 09/04/19
Ended: 09/17/19Samples analyzed
Completed
Individual test results
Mailed 05/08/20
EA site report
Findings and recommendations released 11/18/21
Community meeting
Met 12/09/21
How the testing was conducted
ATSDR invited randomly selected households to participate in the PFAS EA. To be eligible to participate, household residents must have:
- Received their drinking water from the Westfield Water Department.
- Lived north of the Westfield River for at least one year before January 20, 2016 (the date when water treatment for PFAS began).
- Been older than three years at the time of sample collection.
- Not been anemic or had a bleeding disorder that would prevent giving a blood sample.
Households with private wells were not eligible for participation. Measuring PFAS in the blood of people from randomly selected households allows us to estimate exposure from consumption of public drinking water for the entire community in the affected area, even those who were not tested.
Results
In May 2020, CDC/ATSDR released a summary of the biological and environmental test results collected. The full report was released on November 18, 2021, and a summary of the report's findings is presented below. The full report is available for more information.
In September 2019, ATSDR collected samples and other information from participants. ATSDR analyzed data from:
- 459 adults and children.
- 247 households.
- Questionnaires completed by all participants.
- Blood and urine samples provided by most participants.
- Samples of tap water and dust from some homes.
Key takeaways
Levels of some PFAS in the blood of Westfield residents were up to four times higher than national levels.
- Elevated blood levels may be linked with past drinking water contamination.
- Some demographic and lifestyle traits were linked to higher PFAS blood levels.
All tap water samples collected during the EA in 2019 met the EPA's HA for PFAS in drinking water. They also met Massachusetts Department of Environmental Protection's (MassDEP) public health guidelines.
Exposure in children
Older children tended to have lower blood levels of PFOA.
Children who were breastfed had higher blood levels of PFHxS and PFOA.
Infants born to mothers exposed to PFAS can be exposed in utero and while breastfeeding.
Based on current science, the benefits of breastfeeding outweigh the risks for infants exposed to PFAS in breast milk.
Additional testing at the site
Only one PFAS (PFBA) was detected in urine and at low concentrations.
All tap water samples collected during the EA in 2019 met the EPA's HA and MassDEP public health guidelines for PFAS in drinking water.
PFAS contamination in house dust was similar to that reported in other studies.
Future direction
What was learned about PFAS levels in blood
Did you know?
Of the seven PFAS tested in Westfield, five PFAS were detected in more than 85% of the blood samples collected:
- PFHxS
- PFOS
- PFOA
- PFNA
- PFDA
Since 1999, the National Health and Nutrition Examination Survey (NHANES) has measured PFAS levels in blood in the U.S. population. PFAS levels are shown to be age dependent and tend to increase with age in part due to longer periods of exposure.
ATSDR adjusted blood levels of study participants in Westfield for age to enable meaningful comparison to the NHANES dataset. After adjustment, the same three PFAS were still higher than national levels, but slightly less so. Age-adjusted averages may be more representative of the Westfield community.
These three PFAS (PFHxS, PFOS, and PFOA) were also detected in Westfield's water supply as early as 2013. It is likely that contamination began earlier, but no data are available before 2013. By 2016, Westfield's municipal drinking water met the EPA's HA for PFOA and PFOS.
There were more than 3 years and 8 months between the end of exposure via contaminated drinking water and the collection of the EA blood samples.
Because of the long half-lives of PFHxS, PFOS, and PFOA in the body, past drinking water exposures may have contributed to the EA participants' blood levels. Typically, participants who had elevated blood levels of one of the three PFAS also had elevated levels of the other two PFAS. This suggests a common source of exposure, such as the Westfield public water supply. Other sources of exposure were not measured but could have contributed to PFAS concentrations measured in blood of the participants.
Statistical findings
ATSDR used statistical models to study relationships between various demographic characteristics and lifestyle variables of the tested residents. The models showed that, in general:
- Older participants had higher levels of PFHxS, PFOS, and PFOA.
- In males, blood levels for these compounds increased by 0.5% to 1.2% for every year of participant age.
- In females, blood levels for these compounds increased by 1.8% to 3.5% for every year of participant age.
- Males had higher blood levels than females.
- The difference between males and females was larger in younger people.
- Women who breastfed had lower blood levels than women who did not.
There are limited data on:
Residents who had ever used stain-resistant products. They had higher blood levels of PFHxS than residents who reported never using them.
Residents who donated blood at least once a year had lower blood levels of PFHxS and PFOS than residents who never donated.
What the results mean for the Westfield community
This PFAS EA has demonstrated that past exposures to PFAS in drinking water have impacted the levels of PFAS in residents. PFAS are eliminated from the body over a long period of time. This allowed ATSDR to measure PFAS even though exposures through drinking water were lowered years ago.
The exposure contribution from PFAS in drinking water in Westfield has been mitigated. There are still actions community members and city officials can take to further reduce exposures to PFAS and protect public health.
ATSDR does not recommend an alternate source of drinking water at this time for residents getting drinking water from the City of Westfield's public water system. This is based on recent PFAS test results from the municipal water system.
What else can be done
Community members
For information on water quality, become familiar with Consumer Confidence Reports.
Private well owners living in the affected area should consider having their wells tested for PFAS if not done before. Learn more about previous testing for PFAS in private wells in Westfield.
Nursing mothers should continue breastfeeding. Based on current science, the known benefits of breastfeeding outweigh the risks for infants exposed to PFAS in breast milk.
Eliminate or decrease potential exposure to PFAS in consumer products such as stain-resistant products and food packaging materials when possible.
Pay attention to advisories about food consumption, such as local fish advisories.
Discuss any health concerns or symptoms with your health care provider. Share results of PFAS blood testing with your health care provider and make them aware of ATSDR resources for clinicians.
Follow the advice of your health care provider and the recommendations for checkups, vaccinations, prenatal care, and health screening tests.
Follow the advice of your child's health care provider. This includes well-child checkups, vaccinations, and health screening tests. Visit MyHealthfinder for more information. Find more information on environmental exposures and children's health.
City of Westfield
Operators of public water systems should continue to monitor concentrations of PFAS in community drinking water. This will ensure that concentrations of PFAS remain below the EPA's HA or other applicable guidelines for specific PFAS. In addition, the city should:
Share results of PFAS monitoring with community members through the appropriate communication channel.
Properly maintain treatment systems to remove PFAS from the municipal drinking water. This ensures that PFAS concentrations remain below all federal and state guidelines for PFAS in drinking water.
ATSDR
ATSDR is reaching out to doctors, nurses, and other health care providers in your area to provide PFAS clinician guidance and continuing medical education.