Introduction

Our team will be analyzing data from 20 years of United States water quality monitoring collected by the EPA (Environmental Protection Agency). The records begin in 2001 and contain over 4,000,000 observations from water monitoring stations all over the United States. The primary focus of the dataset is to track and monitor the presence of containments - primarily PFAS (poly- and per- fluorinated alkyl substances).

PFAS, which stands for poly- and per- fluorinated alkyl substances, are a group of chemicals used in making Teflon and other fluorotelomers. They are found in household products including nonstick pans, food packaging, cleaning products, and firefighting foam due to its superior properties in hydrophobicity and chemical stability, and they are a common industry runoff from companies like Dupont and Chemours. Because PFAS are fat soluble and difficult to break down, they bioaccumulate in all living species, and everyone in the world’s blood has been contaminated with the toxicant to some degree as they have accumulated in water sources. This class of chemicals is deadly even at extremely trace quantities - on the ppt (parts per trillion) scale. As a reference, this is on the scale of a few seconds in 32,000 years. PFAS chemicals cause adverse reproductive effects, increased liver enzymes, decreased vaccination response, thyroid disorders, pregnancy-induced hypertension and cancer all contributing to elevating death risk. Unlike many other contaminants, PFAS are incredibly hard to remove from water and are considered a “forever chemical”. They are not volatile nor soluble in water, and can pass through the wastewater treatment process with ease, thus flooding our watersheds. Other chemicals like heavy metals and dichloromethane can be removed more easily through treatment processes such as soil vapor extraction for volatiles, a permeable reactive barrier for heavy metals, and ‘pump and treat’ for solubles. None of these treatment methods are very effective for PFAS, unfortunately.

Because of the persistence, toxicity, and now widespread nature of these chemicals, it is imperative to study their presence in our watersheds. The sooner we can figure out how to treat our water for these chemicals and reduce our exposure, the better. As a case study, in the 1950s, Dupont had a PFAS manufacturing plant in West Virginia. Consequently, the runoff led to multiple cases of cow deaths, birth defects, and tumors. Dupont themselves had found that PFAS led to birth defects and various cancers in rats, yet they had not taken any precautionary measures. Dupont eventually settled in court after multiple lawsuits, but the damage in that region had been done. Since then, legislation has been passed in an attempt to reduce further PFAS contamination. However, ultimately these chemicals are in our water and are accumulating in our bodies. Everyone, but especially people in high risk areas, would benefit from further research into PFAS contamination. 

PFAS affect a wide range of stakeholders, including the manufacturing industry, agriculture, most consumers, and the general public. Large industries currently relying on PFAS, such as the aerospace, automotive, electronics or firefighting sectors, are pressured to find PFAS-free alternatives. Farmers and food producers, and thus effectively every consumer, faces PFAS contamination in soil and livestock. This is affecting food safety, sustainability and is leading to an increase in regulations and costs. Public institutions, e.g., water treatment facilities, struggling to remove the contaminant from drinking water, require novel approaches for providing clean and safe water. Ultimately, everyone is affected by PFAS, as they accumulate in the blood and bodies of almost all humans and living beings worldwide posing wide-spread and long-term health risks. As a result, the real-world implications of the PFAS crisis are severe and manyfold. Wildlife and ecosystems worldwide suffer, with PFAS accumulating in rivers, lakes, and food chains. The financial burden on cities and towns for implementing advanced filtration systems is tremendous. Likewise, healthcare costs increase because of widespread long-term illnesses related to PFAS. With rising consumer awareness and government regulations however, the demand for PFAS-free consumer products will increase as well, posing a new economic opportunity for the industry.

The main solution that currently exists to prevent further PFA contamination are water treatment/filtering methods, which can effectively remove PFAs from drinking water. The most common treatment methods include activated carbon filtration and a reverse osmosis system. These methods are both effective in removing PFAs due to their tight filtration activities, but PFAs are becoming increasingly difficult to move. There are other solutions regarding regulatory actions, which would involve enforcing limits on the levels of PFAs that are acceptable in drinking water. There are also regulations to limit the amount of PFAs that can be discharged from industrial sources in waterways. These regulations are beneficial to ensure that PFAs levels are not too dangerous to begin with, rather than trying to combat the problem with filtration systems. Regular testing of water sources also offers possible solutions and is crucial for identifying and addressing potential PFA contamination. Technology is also constantly evolving, leading to more advanced sampling methods that help to identify PFAs at a higher confidence. Some of these newer methods include an advanced oxidation process or bioremediation. In general, the solution currently is constant monitoring and testing methods to try and locate PFAs, as well as filtering out possible PFAs to try and combat the rising levels seen in our environment. 

There are a couple limitations and challenges that exist with the use of PFAs. Scientific studies have shown that exposure to some PFAs in the environment may be linked to harmful health effects in humans and animals. There is an increased risk of some forms of cancer and a reduced ability of the body’s immune system to fight infections. Not only this, but there are also thousands of different PFA chemicals, making it difficult to study, identify, and assess the potential human health and environment risks. They are often present at low detection levels and sampling methods may be difficult. For example, many of the field materials used in sampling may contain PFAs themselves. PFAs chemicals also do not break down easily, allowing them to move through the environment and contaminate drinking water and soils without breaking down over time. This has a large impact on wildlife, soil health, and water sources. PFAs are found in rivers, lakes, and watersheds all over the world, and have contaminated many of our drinking water supplies. The harm that our environment faces from PFAs is a long-term environmental threat, since it affects the stability of our ecosystems, but also raises a larger challenge about the regulations in place to prevent further introduction of these chemicals into our environment. The best way to protect ourselves from PFAS is to be aware of the state of our drinking water source, filtering our water, and keeping our government officials and corporations accountable for their actions around safeguarding our natural resources. From a consumer perspective, utilize your purchasing power to eliminate nonstick cookware in your kitchen and avoid packaging containing PFAS.