PFAS Exposure Reduction
It is difficult to provide clear advice on how to reduce exposure to per- and polyfluoroalkyl substances (PFAS) because there are many potential exposure sources. Importantly, even if the source of a person’s exposure is completely removed, it will take years for the internal body burden (levels in the body) of many PFAS to be fully eliminated. Biological half-lives (i.e., the time it takes for plasma concentration to decrease by 50 percent after exposure) vary depending on the PFAS; half-life estimates for the four most studied PFAS (perfluorooctanoic acid [PFOA], perfluorooctane sulfonic acid [PFOS], perfluorohexane sulfonate [PFHxS], and perfluorononanoic acid [PFNA]) range from around 2 to 8 years (Li et al., 2018; Olsen et al., 2007). These long biological half-lives are due to reabsorption in the kidney and enterohepatic recirculation, both processes greatly reducing the capacity to eliminate PFAS (Harada et al., 2007).
In developing this chapter, the committee first created a conceptual model for exposure reduction (see Figure 4-1). The premise of this model is that if any exposure pathway is interrupted, exposure should be reduced. For example, if PFAS were no longer used in industries, they would not be in consumer products or waste streams, so exposures would be reduced. Similarly, if PFAS in the environment are cleaned up, exposures will decrease.
Support for the committee’s conceptual model is found in the changes in exposure at the population level due to industry-wide changes in PFAS production. For example, serum PFAS concentrations in the United States declined over time following the 3M company’s (Maplewood, Minnesota) voluntary phase-out of perfluorooctanyl chemicals and related precursors, including PFOS and PFOA, in 2000 (ITRC, 2017) (see Figure 4-2). Therefore, there is evidence that removing these chemicals from products on a large scale can result in lower levels in a population.
SOURCES AND ROUTES OF EXPOSURE TO PFAS
The sources of and routes of exposure to PFAS are an active area of investigation. What is well known is that PFAS exposure is highly complex, with pathways that include occupational exposures, environmental contamination, consumer product use, and food exposures. Specific sources of exposure include, for example, jobs in fluorochemical manufacturing facilities or where PFAS-containing products, such as textiles or food contact materials, are made. Other jobs with a known increased risk of exposure to PFAS include electroplating; painting; carpet installation and treatment; serving as a military or civilian firefighter, which entails using PFAS-containing foams in training exercises and wearing PFAS-impregnated gear; and jobs that require prolonged work with ski wax (ATSDR, 2021). In addition, food workers and others in the hospitality industry may have elevated exposure since they handle PFAS-containing food packaging as part of their job duties (Carnero et al., 2021; Curtzwiler et al., 2021; Schaider et al., 2017).
Ingestion is the most well-studied route of exposure in nonoccupational settings (Trudel et al., 2008). Ingestion of PFAS can occur through drinking contaminated water; eating contaminated seafood; or consuming other contaminated foods, such as vegetables, game, or dairy products (Bao et al., 2019, 2020; Death et al., 2021; Domingo and Nadal, 2017; Herzke et al., 2013; Li et al., 2019). PFAS are often used in cookware and in materials that came in contact with food, such as microwave popcorn bags or packaging used for fast foods or processed foods (Carnero et al., 2021; Curtzwiler et al., 2021; Schaider et al., 2017). Exposure can also occur through accidental ingestion of PFAS-containing dusts (Fraser et al., 2013). PFAS cross the placenta, and PFAS from the mother’s body burden can be passed on to her developing fetus (Gao et al., 2019; Manzano-Salgado et al., 2015). Maternal transfer of PFAS can also occur through breastfeeding (Serrano et al., 2021; Zheng et al., 2021).
Inhalation and transdermal exposures are less well studied. Inhalation of PFAS is well documented in occupational settings that use aerosolized PFAS (Gilliland, 1992). Volatile PFAS have been detected indoors (Fromme et al., 2015; Morales-McDevitt et al., 2021), and inhalation near factory emissions and incinerators contributes to exposures in nearby communities (Fenton et al., 2021). There
are as yet no data formally evaluating inhalation from showering in contaminated water, but this is an active area of research.
PFAS are used in thousands of products (e.g., products containing water; stain-resistant clothing; and personal care products, such as sunscreen, makeup, and dental floss). PFAS are also used in such products as paint, textiles, firefighting foam, electroplating material, ammunition, climbing ropes, guitar strings, artificial turf, and soil remediation products (Glüge et al., 2020). The extent to which use of products contributes to human exposures is unkown, however, because the relative contribution of PFAS exposures from sources other than food or water is not well characterized (DeLuca et al., 2021).
The presence of PFAS in everyday consumer products may be an important source of exposure for the general population, but this likely varies greatly by individual (Rodgers et al., 2022). Consumer products are often treated with fluoropolymers to impart water and stain resistance, and fluoropolymers can result in exposure to the nonpolymer PFAS discussed in this report in several ways. Nonpolymer PFAS can be present as impurities in fluoropolymer-containing products because these PFAS are used as processing aids in chemical production or are degradation products of the fluoropolymers (Rodgers et al., 2022; Schellenberger et al., 2019). Moreover, fluoropolymer PFAS can degrade (biodegradation) slowly when exposed to water and release fluorotelomer alcohols, which are precursors to nonpolymer PFAS. Once the precursor PFAS are in the human body, they can transform to such PFAS as PFOA, PFOS, and PFHxS (Washington and Jenkins, 2015).
APPROACH TO DETERMINING ADVICE ON PFAS EXPOSURE REDUCTION
To inform its recommendations on how clinicians can advise patients on PFAS exposure reduction, the committee looked at several sources of evidence. The committee contracted with a consultant to review the literature evaluating the effectiveness of behavioral interventions in reducing exposure to PFAS. The consultant also reviewed several studies that model estimates of PFAS intake, which could inform predicted changes in serum PFAS levels if exposure routes were modified (see Appendix E). The committee reviewed studies on PFAS exposure through breastfeeding since this route impacts a vulnerable population and is of particular interest to people in PFAS-impacted communities, as voiced by speakers at the committee’s town halls (see Appendix B). The committee also evaluated studies of medical interventions for reducing internal levels of PFAS (e.g., phlebotomy or taking of prescription drugs). PFAS exposure pathways discussed in Chapter 1 were used to outline strategies clinicians can use to determine whether a patient may be at risk of PFAS exposure based on residential and work history. In addition, the committee reviewed advice from other entities on PFAS exposure reduction, such as that provided by nongovernmental organizations, state and local governments, and other countries.
CONTRIBUTION OF INDIVIDUAL EXPOSURE SOURCES TO HUMAN EXPOSURE
Behavioral Intervention Studies
Studies evaluating the impact of behavior change on reducing exposures would help determine the impact of behavior on human exposure. This section, based on a literature review conducted by LaKind Associates (see Appendix E), provides an overview of the literature available to inform what individuals can do to reduce their serum PFAS levels. The literature review used a three-step approach to identify relevant publications in PubMed, EMBASE, and Google Scholar (see Appendix E for keywords and the search strategy). Studies were selected that entailed interventions designed to reduce human exposure to PFAS, specifically interventions that could be carried out by individuals. Secondary references of retrieved articles were reviewed to identify publications not found through the electronic search. An additional literature search was then conducted to identify reviews containing estimates of human PFAS intakes. The final search date was March 5, 2021.
The reviewed intervention studies are presented here by exposure route, with the primary focus being on drinking water and diet. Literature on interventions for other exposure sources, such as dust and
consumer products, is more limited. Lastly, breastfeeding is an important potential source of exposure for infants, and lactating could reduce parents’ PFAS levels. After reviewing the relevant studies, this section concludes by assessing the effectiveness of behavior modifications based on the current literature.
Drinking water has been identified as a substantial source of PFAS exposure for many populations (Andrews and Naidenko, 2020; Domingo and Nadal, 2019). Studies of interventions focused on drinking water are consistent in demonstrating the effectiveness of water filtration at reducing levels of certain PFAS. Consumers have a variety of options for filtering PFAS from drinking water, including whole-house, under-sink, and filtering-pitcher devices. The committee identified seven publications and one agency report evaluating possible drinking water interventions. Of these, five (Ao et al., 2019; Herkert et al., 2020; Iwabuchi and Sato, 2021; MDH, 2008; Patterson et al., 2019) evaluate use of whole-house, under-sink, and filtering-pitcher devices, and three (Ao et al., 2019; Gellrich et al., 2013; Heo et al., 2014) evaluate differences in PFAS concentrations between tap water and bottled water.
In a study of real-world uses of water filtration options, Herkert and colleagues (2020) tested municipal, well, and filtered (n = 89) and unfiltered (n = 87) tap water in residences (N = 73) in North Carolina for 11 PFAS. The filters tested varied in both type and filtration method (reverse osmosis, granulated activated carbon, single-stage, dual-stage). Notably, reverse osmosis and dual-stage filters were found consistently to remove most measured compounds at an average of ≥90 percent efficiency; some short-chain replacement PFAS are difficult to remove with carbon filtration (Herkert et al., 2020). Use of bottled water can also be a way to reduce PFAS exposure from drinking water, although some bottled waters contain detectable levels of C-3–C-10 perfluorocarboxylic acids (PFCAs) and C-3–C-6 and C-8 perfluorosulfonic acids (PFSAs) (Chow et al., 2021). In Parkersburg, West Virginia, for example, the use of bottled water resulted in a dramatic reduction in serum PFOA levels among a contaminated community living near a Teflon-manufacturing plant (Emmett et al., 2006).
Changes in diet may potentially reduce PFAS exposure, given that PFAS can be present in a number of food products, including wild-caught fish and game, livestock, and produce, as well as prepared foods. Fish and seafood have been identified as sources of PFAS, but the levels of PFAS vary by fish type and water body (Sunderland et al., 2019). PFAS-contaminated drinking water can also impact home-grown vegetables (Brown et al., 2020; Emmett et al., 2006). The majority of ingestion-based intervention studies focused on seafood preparation, but there was no strong evidence that fish preparation methods influenced PFAS levels (Alves et al., 2017; Barbosa et al., 2018; Bhavsar et al., 2014; Del Gobbo et al., 2008; Hu et al., 2020; Kim et al., 2020; Luo et al., 2019; Taylor et al., 2019).
A study on PFAS exposure from indoor dust found significantly lower PFAS levels in vacuumed dust from rooms with PFAS-free furnishings relative to control rooms (78 percent reduction, 95% CI: 38–92). Results suggest that modifying personal behavior to be capable of identifying and purchasing PFAS-free furnishings can decrease exposure levels from indoor dust (Scher et al., 2019).
Literature on PFAS in consumer products is available only for nonstick pans and dental floss, and these studies have several weaknesses, including recall bias, small sample sizes, and lack of replication. Their results do not provide enough evidence to suggest that modifications in behavior relative to those products would decrease PFAS exposure, but in the absence of such evidence, consumers should be aware of which products contain PFAS (Scher et al., 2019; Young et al., 2021).
Another factor that complicates consumer choices aimed at avoiding PFAS is the lack of consistent labeling of products. A recent study (identified after Appendix E of this report had been completed) that screened 93 market items across three different product types (furnishings, apparel, and bedding) found that PFAS were present in many items that were labeled as green or nontoxic (Rodgers et al., 2022).
To summarize, the available literature is limited in presenting recommendations for effective behavior modifications to reduce internal levels of PFAS. In places with water contamination, individuals can reduce their exposure through use of water filtration. In places without PFAS water contamination or workplace exposure, diet is believed to be the primary exposure route, but there is limited information with which to recommend dietary interventions. No intervention study has examined exposure reduction and its impact on serum concentrations, likely in part because to fully show effectiveness for an
intervention, it would have to be conducted over a long enough time to account for the long half-lives of PFAS.
Modeled Estimates of PFAS Intakes
In the absence of studies demonstrating the impact of interventions on reducing PFAS exposure, exposure models may help inform predicted changes in serum PFAS levels if exposure routes are modified. Pharmacokinetic modeling is useful for estimating the body burden from different exposure routes, but such models are often limited by the many assumptions made about intake factors (e.g., food contamination). High-quality data on the distribution of PFAS in different food types and consumer products are sparse. Nonetheless, pharmacokinetic models can be used to estimate the variability possible in exposure reduction and the impact of changes with different parameters. Although imperfect, exposure modeling can provide, at a minimum, an estimate of the change in internal PFAS body burden if PFAS levels in diet or water were decreased.
Studies that have estimated intake of PFOS and PFOA have been used to determine the dominant routes of exposure in communities without contaminated drinking water (see Appendix E). Estimates of how much PFAS exposure comes from diet in adults vary widely, from 16–99 percent for PFOA to 66–100 percent for PFOS (Egeghy and Lorber, 2011; Haug et al., 2011; Lorber and Egeghy, 2011; Sunderland et al., 2019; Vestergren and Cousins, 2009); no estimates are available for individual food products. For dust, the estimates are 1–11 percent for PFOA and 1–15 percent for PFOS (Sunderland et al., 2019). For PFOA, the dominant routes are thought to be oral exposure resulting from consumption of fish and seafood, drinking water, and ingestion of dust. For PFOS, the dominant routes are thought to be ingestion of food and water, ingestion of dust, and hand-to-mouth transfer from treated carpets (Trudel et al., 2008). Residual PFOA in food packaging (used to greaseproof food-containing paper products) is another potential route of exposure (Trudel et al., 2008); polyfluoroalkyl phosphoric acids in food packaging can also be metabolized in the body to PFOA (Begley et al., 2005; Carnero et al., 2021; Curtzwiler et al., 2021; Schaider et al., 2017).
Interpretation of the estimated intake studies is challenged by several factors. First, while diet appears to be a major pathway of exposure, there is little information on PFAS in commercial foods commonly consumed in the United States. The U.S. Food and Drug Administration (FDA) has released PFAS data for certain foods that could be used to model source contributions to PFAS intake in future studies. However, the FDA data for produce, meat, dairy, and grain products are based on a small sample size, and the results “cannot be used to draw definitive conclusions about the levels of PFAS in the general food supply.”1
The relative importance of different PFAS sources varies by study, population, and time period of exposure (Sunderland et al., 2019). The production and use of individual PFAS have changed over time and will continue to do so. Serum PFAS levels in the United States dropped following the phase-out of production of PFOS and PFOA; however, exposures to C9–C11 PFCAs have not followed the same trend. Thus, it is important to use recent environmental, consumer product, and dietary data to develop robust estimates of current dominant pathways of PFAS exposure. In a recent review evaluating nonoccupational intakes via background PFAS exposures, De Silva and colleagues (2021) observed that the inconsistency among studies in the relative importance of different exposure sources may be due to differing concentrations of PFAS in sources, as well as the assignment of differing values for exposure intake factors (e.g., exposure frequency and duration). The authors conclude, “Without rigorously conducted exposure studies it is challenging to rank order the most important human exposure pathways and without these data, our ability to design evidence-based exposure intervention strategies will be limited.”
1 See https://www.fda.gov/food/chemicals/analytical-results-testing-food-pfas-environmental-contamination (accessed May 12, 2021).
Exposure to PFAS Through Breastfeeding
Breastfeeding is a route of exposure of great interest to people who spoke at the committee’s town halls. Breast milk is the only food many infants receive in their first 6 months of life, and if the breast milk they receive is contaminated with PFAS, it may take years for their body burden to be reduced, given the long half-lives of some PFAS.
In her testimony at the committee’s first town hall (April 7, 2021), Loreen Hackett (PFOA Project New York) stated that in her view, health care mantras such as “breast milk is best” need to be thoroughly reevaluated in exposed communities, noting that breastfeeding “may double or triple PFAS levels in an infant compared to the mothers thereby increasing risks to their developing systems.” She stressed that families in exposed communities cannot make informed reproductive choices or other family decisions without improved information tailored to their situation, and she relayed concerns among community members expressing guilt for unknowingly poisoning their child over the course of pregnancy and breastfeeding.
Nonetheless, data on PFAS in breast milk are very limited. A few studies measuring PFAS in breast milk in North America (Kubwabo et al., 2013; Tao et al., 2008; Zheng et al., 2021) indicate transfer from the parent to the child during the first months of life. And although the concentrations in breast milk are generally much lower than the concentrations in maternal serum (Cariou et al., 2015; Kärrman et al., 2007; Kim et al., 2011; Liu et al., 2011), breastfeeding has been shown to contribute significantly to children’s serum levels of some PFAS (Gyllenhammar et al., 2018, 2019; Koponen et al., 2018). In a cohort of 2- to 4-month-old infants in Sweden, for example, bottle-fed infants had mean serum concentrations twice as low as those of their exclusively breastfed counterparts, and serum levels of PFOA, PFNA, and PFHxS increased 8−11 percent per week of exclusive breastfeeding (Gyllenhammar et al., 2018). Where measured and estimated PFAS concentrations in breast milk in the United States have been compared with drinking water screening values of the Agency for Toxic Substances and Disease Registry (ATSDR), some exceedances have been observed, especially in communities impacted by PFAS contamination (LaKind et al., 2022) (see Figure 4-3).
Whether lactational exposure to PFAS can have adverse health effects in children has not been well studied to date. Formula feeding can also lead to PFAS exposure through either contaminated formula or formula reconstituted with contaminated drinking water. Given the increased exposures observed in breastfed versus formula-fed infants, it is not clear whether the benefits of breastfeeding outweigh the risks to the child among lactating persons with very high levels of PFAS exposure.
Guidance to breastfeed remains the best feeding advice for most infants given the many benefits of breastfeeding for both mothers and babies.2 Even though PFAS exposures have been occurring for many years, research has consistently shown benefits of breastfeeding, providing confidence in the traditional guidance, although a more in-depth understanding of this exposure route is warranted to inform protection of such a vulnerable population.
MEDICAL INTERVENTIONS FOR POTENTIALLY REDUCING PFAS BODY BURDEN
There have been few studies overall and no clinical trials evaluating treatments to reduce PFAS body burden, even in cases of very high exposure. The few evaluations available have focused on the use of cholesterol-lowering medications and phlebotomy.
PFAS are secreted in the bile and have enterohepatic recirculation; therefore, researchers have been interested in medications that enhance bile sequestration as potential approaches for reducing PFAS body burden. Cholestyramine is a bile-sequestering agent that is used mainly to reduce low-density lipoprotein (LDL) cholesterol. In a cross-sectional study of C-8 Health Project participants, 36 of 56,175 adults were being treated with cholestyramine and were found to have lower levels of PFAS compared with those not taking this medication (Ducatman et al., 2021). Another medication, probenecid, was not
2 See https://www.cdc.gov/breastfeeding/about-breastfeeding/why-it-matters.html (accessed May 23, 2022).
significantly associated with serum PFAS levels in this study. Cholestyramine has also been evaluated in a few small case studies of 1 to 20 individuals (Genius et al., 2010, 2013). Results of these studies suggest that cholestyramine may be an effective treatment to accelerate PFAS fecal excretion, but replication in studies with more participants is needed. No studies have assessed whether PFAS levels rebound when treatment with cholestyramine is discontinued.
Phlebotomy has been discussed as a way to reduce the body burden of PFAS. Genuis and colleagues (2014) asked six patients aged 16–53 years from a highly PFAS-exposed family to submit to routine blood draws (500 mL) for up to 5 years, resulting in a cumulative 2–12 L of blood drawn. The levels of PFOA, PFOS, and PFHxS decreased in these individuals over that time at a faster rate than expected according to first-order excretion kinetics. In a recent randomized controlled trial of 285 firefighters, serum PFOS and PFHxS concentrations were significantly reduced in subjects who regularly donated blood or plasma over 12 months compared with the control group; the decline was more pronounced in the plasma donation group (Gasiorowski et al., 2022). While these studies indicate that phlebotomy can be effective at reducing PFAS levels in blood, there are no established serum concentrations of PFAS at which the benefits of this intervention reasonably outweigh the harms, and the safety and utility of this approach are uncertain.
EXISTING ADVICE ON PFAS EXPOSURE REDUCTION
Several federally funded academic projects and nonprofit organizations provide information about PFAS, including how to identify potential community exposure and reduce personal exposure. Because concerned individuals look to online resources for data and information, a few of the resources are summarized here, with the caveat that they have not been tested empirically, and the data they present may be incomplete, or the sources on which the data are based may be missing. Furthermore, in discussing these online resources, the committee is not endorsing them, nor do their content and conclusions necessarily represent the committee’s views. In addition to the sources discussed below, many state health departments have state-level resources on PFAS that may be trusted sources of information.
PFAS-REACH (Research, Education, and Action for Community Health) is a project funded by the National Institute of Environmental Health Sciences to develop guidance materials and data interpretation tools for use by communities impacted by PFAS-contaminated drinking water. The project is led by Silent Spring, Northeastern University, and Michigan State University, with collaboration from community partner organizations that include Testing for Pease, Massachusetts Breast Cancer Coalition, and Community Action Works. The project’s online resource center, PFAS Exchange, provides factsheets and interactive maps; a factsheet on how to reduce one’s exposure is most relevant to the discussion in this chapter.3Figure 4-4 shows the PFAS Exchange recommendations.
3 See https://pfas-exchange.org/how-to-reduce-your-exposure-to-pfas (accessed June 17, 2022).
PFAS Project Lab
Northeastern University, one of the academic partners for the PFAS-REACH project, operates the PFAS Project Lab within its Social Science Environmental Health Research Institute (SSEHRI). Among the Lab’s publicly available resources is the PFAS Sites and Community Resources Map.4 The map interface provides the locations of known and suspected PFAS contamination sites (see Figure 4-5), as well as community resources and state action. The data were collected from government websites, news articles, and publicly available sources. The map began as a collaborative effort with the Environmental Working Group (EWG), an advocacy group (see below and Chapter 1, Figure 1-2). The SSEHRI map “aims to help affected residents and community groups to access information about data in their states and learn how to connect with other activists working on PFAS issues.”5
Environmental Working Group
The EWG is included as a data source in the PFAS Project Lab. The EWG site also provides an interactive map that “serves to show the extent of PFAS water contamination as documented by states, the department of defense and EWG’s testing,” providing the locations of industrial and military sites with known PFAS contamination.6 Additionally, the EWG provides a guide for avoiding exposure to PFAS chemicals. The EWG’s recommendations are similar to those in the PFAS-REACH factsheet (see Figure 4-4) regarding consumer choices. The EWG has developed several consumer guides providing information on the chemicals (not just PFAS) present in a variety of commercial products, including sunscreen, cosmetics, personal care and beauty products, bug repellants, and household cleaners, among others.
4 See https://experience.arcgis.com/experience/12412ab41b3141598e0bb48523a7c940 (accessed May 25, 2022).
5 See https://www.ewg.org/news-insights/news/mapping-pfas-contamination-crisis (accessed June 15, 2022).
6 See https://www.ewg.org/interactive-maps/pfas_contamination/#about (accessed June 17, 2022).
FINDINGS AND RECOMMENDATIONS
The committee found that few evidence-based recommendations can be made for reducing exposure to PFAS on an individual level.
Occupational exposures to PFAS may be much higher than community exposures. In accordance with the hierarchy of controls, methods for reducing workplace exposure can include replacing the chemical with a less hazardous one; engineering controls, such as ventilation to reduce inhalation of the chemical; administrative controls, such as rotating operations to reduce the amount of time an individual worker is around a chemical; or personal-level controls, such as personal protective equipment, including gloves and masks.
Ingestion is an important route of exposure to PFAS in the general population; thus it is important to reduce consumption of PFAS in drinking water and foods. Contamination of drinking water with PFAS is a widespread problem in the United States, and the extent of the contamination has not been completely characterized. Both municipal and private sources of drinking water (e.g., private wells) can be contaminated with PFAS as a result of fluorochemical manufacturing, use of firefighting foams, or discharge of landfill leachate to drinking water sources. If PFAS are in drinking water, switching to another source of water with lower PFAS concentrations will reduce exposure.
Consumption of game may also cause to exposure to PFAS. To date, 11 states have developed or are in the process of developing advisory guidelines for fish, wildlife, and other food products to protect human health from exposure to PFAS. These advisories offer guidance on limiting the quantity of consumption of these foods. These advisories are state-specific and range from do not eat (e.g., fish or deer in Michigan with PFOS concentrations over 300 parts per billion [ppb]) to no need to limit consumption (e.g., New Jersey fish with more than 0.56 nanograms per gram [ng/g] of PFOS). The Environmental Council of the States has compiled information from participating states on state PFAS standards, advisories, and guidance values (ECOS, 2020).
For clinicians, based on its review of the evidence on PFAS exposure reduction, the committee makes the following recommendations:
Recommendation 4-17: Clinicians advising patients on PFAS exposure reduction should begin with a conversation aimed at first determining how they might be exposed to PFAS (sometimes called an environmental exposure assessment) and what exposures they are interested in reducing. This exposure assessment should include questions about current occupational exposures to PFAS (such as work with fluorochemicals or firefighting) and exposures to PFAS through the environment. Known environmental exposures to PFAS include living in a community with PFAS-contaminated drinking water, living near industries that use fluorochemicals, serving in the military, and consuming fish and game from areas with known or potential contamination.
Recommendation 4-2: If patients may be exposed occupationally, such as by working with fluorochemicals or as a firefighter, clinicians should consult with occupational health and safety professionals knowledgeable about the workplace practices to determine the most feasible ways to reduce that exposure.
Recommendation 4-3: Clinicians should advise patients with elevated PFAS in their drinking water that they can filter their water to reduce their exposure. Drinking water filters are rated by NSF International, an independent organization that develops public health standards for products. The NSF database can be searched online for PFOA to find
7 The committee’s recommendations are numbered according to the chapter of the main text in which they appear.
filters that reduce the PFAS in drinking water included in the committee’s charge. Individuals who cannot filter their water can use another source of water for drinking.
Recommendation 4-4: In areas with known PFAS contamination, clinicians should advise patients that PFAS can be present in fish, wildlife, meat, and dairy products and direct them to any local consumption advisories.
There are fewer evidence-based exposure-reduction recommendations for patients without known sources of exposure:
Recommendation 4-5: Clinicians should direct patients interested in learning more about PFAS to authoritative sources of information on how PFAS exposure occurs and what mitigating actions they can take. Authoritative sources include the Pediatric Environmental Health Specialty Units (PEHSUs), the Agency for Toxic Substances and Disease Registry (ATSDR), and the U.S. Environmental Protection Agency (EPA).
Recommendation 4-6: When clinicians are counseling parents of infants on PFAS exposure, they should discuss infant feeding and steps that can be taken to lower sources of PFAS exposure. The benefits of breastfeeding are well known; the American Academy of Pediatrics, the American Academy of Family Physicians, and the American College of Obstetricians and Gynecologists support and recommend breastfeeding for infants, with rare exceptions. Clinicians should explain that PFAS can pass through breast milk from a mother to her baby. PFAS may also be present in other foods, such as the water used to reconstitute formula and infant food, and potentially in packaged formula and baby food. It is not yet clear what types and levels of exposure to PFAS are of concern for child health and development.
Additionally, there is a critical need for more data to understand PFAS exposure among breastfed infants:
Recommendation 4-7: Federal environmental health agencies should conduct research to evaluate PFAS transfer to and concentrations in breast milk and formula to generate data that can help parents and clinicians make shared, informed decisions about breastfeeding.
At this time, it not possible to eliminate all sources of PFAS exposure. There are some sources people can try to limit if they desire and have the resources to do so. If patients are resource-limited, it is most important that if PFAS contamination of their water is known or suspected, they use water filtration or another source of water for drinking that is lower in PFAS. In keeping with the principle of adaptability, it is also important to direct patients to reliable sources of information on PFAS, such as ATSDR, the U.S. Environmental Protection Agency, and state and local departments of public health so they can obtain accurate and up-to-date information.
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