This study assessed mothers (of young children) living in a severely PFAS-contaminated region. These mothers were exposed to elevated levels of PFOA through drinking water till 2017. The data was used to determine the environmental and individual factors that might influence the perception of health risks due to exposure to PFAS. Additionally, we investigated whether perceived risk, along with environmental factors linked to PFAS exposure, was associated with self-reported diseases in the mothers. From some of the participants, we also evaluated the real environmental and individual influencing factors that might be associated with the serum PFAS levels in the mothers.
The perceived risk of being exposed to PFAS was strongly associated with the trust in scientific and political institutions and information from social media. We found that the risk perception of the participants was associated with the information provided to the public by institutions and the media (Goldstein, 2017). PFAS contamination is often “invisible”, i.e., individuals are unable to detect such substances in the water or food. Moreover, the effects are uncertain, and there is a long gap between the first exposure and the detection of contamination and possible consequences in individuals (Goldstein, 2017). Interestingly, the trust in scientific institutions was positively associated with perceived risk; thus, indicating that those who had greater trust in scientific information perceived stronger detrimental effects of PFAS (Steenland et al., 2020). The effect of trust in political institutions was strongly associated with the reduction in perceived risk. After the detection of PFAS contamination, the local authority equipped water treatment plants with granular activated carbon filters, while a surveillance program of the exposed population was conducted (Pitter et al., 2020). The trust in these mitigation and health measures reduced the perception of risk (Viklund et al., 2003). Previous studies have reported several common concerns of the members of the community who faced PFAS contamination: health issues due to unhygienic living conditions, loss of confidence in governmental institutions, feeling insecure, frustration, and lack of control/agency over the situation; all these issues can be resolved by a renewed trust in political institutions (Calloway et al., 2020). Conversely, trust in information on social media reshapes public risk perception by increasing self-reported knowledge (Liu et al., 2021). Within the population of child-bearing women, those who were full-time employees perceived a lower PFAS health risk than housewives or unemployed individuals, suggesting that maternity (probably linked to the status of housewife or unemployment) might make them more worried about their children’s future (Signorino, 2012). Previous studies (Jetten et al., 2012) suggested that having a strong network of friends imparts psychological benefits, but in this context, it might contribute to amplifying the perceived risk. Specifically, within the population of the mothers living in the “red zone” (highly contaminated), mothers with a wider social network were more connected to the community and were frequently reminded of the possible risks of environmental contamination.
The analysis of the self-reported diseases showed that mothers with higher risk perception related to PFAS exposure reported more health issues and autoimmune disorders. Similarly, participants in the surveillance program with known PFAS levels showed higher occurrences of self-reported diseases. High-risk perception is associated with a change in the lifestyle and adoption of health-protective measures (Gerber & Neeley, 2005; Coi et al., 2016). Exposure to chronic environmental pollution was associated with an increase in the general distress among contaminated communities because these individuals face uncertainty, worries related to health risks (cancer clusters, unexplained deaths, worsening health conditions, and the future health of children) (Calloway et al., 2020; Banwell et al., 2021), and the potential of further being exposed to the contaminants every day (e.g., water sources and usage) (Calloway et al., 2020). A continuous and high-stress response can cause immune dysregulation, which might lead to autoimmune disease by altering or amplifying cytokine production (Stojanovich et al., 2009).
Among environmental factors, consumption of tap water was associated with more reports on health issues, particularly of cancer, as well as a longer residence time. The residents of Red Zone A had two times higher risk of liver diseases than those of Red Zone B. Drinking contaminated water is a well-known source of PFAS exposure (Domingo & Nadal, 2019). This could be a reason for the long-term residents of Red Zone A to report a higher PFAS concentration (Pitter et al., 2020). Several studies found an association between PFAS exposure and markers of liver diseases (Armstrong et al., 2019; Bassler et al., 2019), while the association between PFAS exposure and common types of cancer in young mothers (e.g., breast cancer) showed mixed results (Bonefeld-Jørgensen et al., 2014; Hurley et al., 2018; Tsai et al., 2020). Additionally, a higher risk of cardiovascular diseases was reported in residents of Red Zone A compared to those living in Red Zone B. This result was similar to that found in previous studies that showed an association between serum blood PFAS concentration and the risk of cardiovascular diseases (Shankar et al., 2012; Huang et al., 2018), where a platelet-centered mechanism might be the biological link (De Toni et al., 2020; Meneguzzi et al., 2021).
Factors derived from environmental contamination, such as the contamination of food, may or may not be associated with real exposure (Dettori et al., 2020), and this discrepancy can be modulated by a combination of objective (e.g., exposure levels) and subjective factors (e.g., socioeconomic conditions and cultural values). In this study, we evaluated which factors influenced PFAS levels among mothers of young children. Pregnancy-related variables (breastfeeding, number of abortions, number of children, and time since last pregnancy) were the major determinants of PFAS levels in the mother’s blood. Breastfeeding significantly influenced all log-PFAS models, especially the log-PFOA model, which estimated a large effect up to the birth of the third child. This result confirmed that mothers who breastfed exhibited lower PFAS concentrations than those who did not breastfeed. A significant quantity of PFAS can be removed from the body through breast milk (Mondal et al., 2014). Conversely, PFAS can be passed through breastfeeding from the mother to nursed infants and accumulate with the PFAS from prenatal placental transfer and postnatal exposure to contaminants (e.g., through environmental exposure, diet, or tap water consumption) (Kim et al., 2020). We found that the area of residence was another significant predictor of PFAS concentration in the mother’s blood (Pitter et al., 2020). Based on our analysis, individuals living in the municipalities of the Red Zone located above the site of groundwater contamination (Red Zone A) showed a higher blood PFAS level than those residing outside (Red Zone B). Additionally, participants from municipalities outside Red Zone A showed lower PFAS concentrations, especially when they consumed tap water less often. The association between PFAS levels and other variables, such as the source of meat or vegetables, was lower in our study than that reported for the general population (Brantsaeter et al., 2013; Berg et al., 2014).
Most of the questionnaires were completed by the participants. From some of the participants, we also obtained a measure of the serum blood PFAS concentration. The variables recorded allowed us to conduct three types of analyses to address specific research questions. This was the first study to simultaneously analyze the perceived risk, health outcomes, and PFAS determinants in the same population. Some results, especially those regarding the determinants of PFAS concentration, are very important (Mondal et al., 2014). This study had a small sample size, which might affect the generalizability of our results. Moreover, the participants were mothers who volunteered to participate in an online survey that was mainly spread through word-of-mouth. The online modality implied a certain selection bias since certain types of participants were under-represented, for example, those with a low education level. Basically, the cross-sectional nature of the study and self-reporting of diseases limited the causal attribution of the results. To overcome this latter point, we introduced some confounding variables in the analysis (e.g., age, education level, and employment status) to keep into account the non-probability sampling and to perform an adjustment of the risk estimates. In terms of health outcomes, we grouped and analyzed several diseases into a single comprehensive category, which limited our ability to derive strong associations between the PFAS measures and a specific disease.