Table of Contents
Abstract
This research paper explores GenX pollution of Cape Fear River in North Carolina and neighboring states. This study will focus on the history of GenX, the manufacturer of the toxin and other chemicals, its associated toxicity and what is being done about the pollution. The study will be supported by statistical data to ensure reliability. In brief, research reveals that GenX is associated with major toxicity levels. These include Oral toxicity, inhalation and dermal toxicity. It is also closely related to skin irritation and corrosion as well as carcinogenicity. In a study conducted to review the new technology that Chemours uses to manufacture GenX, it was noted that the chemicals used had negative impacts on reproduction in mice. It was also associated with kidney and liver damage as well as significant weight loss and changes in cholesterol. As a result of such health hazards, the authorities in North Carolina have imposed several penalties on Chemours, the manufacturer of GenX and other related toxins. Similarly, the citizens of North Carolina are always questioning the dumping of Chemours chemical effluents into the river. This paper will examine these matters in details in the body.
Keywords: Chemours, GenX, Pollution, North Carolina, Cape Fear River, Toxicity, health hazards, PFOA.
Standard Abbreviation:
PFOA- Perfluorooctanoic acid
SVHC- Substances of very high concern
APFO- Ammonium salt of PFOA
USEPA- USA Environment protection agency.
Ppt- Parts per trillion
Introduction-Background and History
Chemours is an American manufacturer of chemicals. It was a spinoff from DuPont, which in turn is a bigger manufacturer of Teflon chemicals in the USA. The two firms are closely linked to the production of GenX which is one of the major pollutants in Cape Fear River. In 2009, DuPont introduced GenX to replace PFOA. The replacement followed a class-action suit against DuPont for the production of PFOA which is known to possess health and environmental hazards. In brief, PFOA is used in the manufacture of coatings for waterproof clothing as well as stain-resistant carpeting. The compound is also useful in the production of Teflon. The abbreviations PFOA and C8 are used interchangeably to refer to the same products. After DuPont was barred from producing the PFOA, it embarked on the production of an alternative called GenX. This compound consists of shorter chains compared to the PFOA. Its chemical structure is abbreviated as PFPrOPrA (Sun et al., 2016). In the past one year, various studies show that GenX has similar health effects as the previous PFOA (Lerner, 2017). These effects include reproduction problems as well as cancer. The literature review below will check each of these effects in details below.
In brief, the levels of GenX present in the Cape Fear River drinking water is 631 ppt. (0ne sample measured 4,500 parts per trillion). This value is far much higher than the recommended level of PFOA present in the water. In the recent past, USEPA set the recommended level of PFOS and PFOA found in water at 70ng/L (Sun et al., 2016). In a study conducted by Sun et al. (2016), it was noted that GenX was the primary pollutant in Cape Fear River.
Literature Review
Statistical Figures
Evidence shows that the levels of GenX present in Cape Fear River are above the recommended level. To be precise, it is estimated to be 631ppt at points near Chemours production plant (Lerner, 2016; Sun et al., 2017). The recommended level by USEPA is 70ppt. Other agencies such as the New Jersey Drinking Water Quality Institute have set the level to as low as 14ppt (Post, et al., 2009). Therefore, water contamination in Cape Fear River is extremely high. The diagram below shows a road map of concentrations of GenX compound in North Carolina drinking water.
Figure 1 shows the levels of GenX concentration at different points along Cape Fear River.
Adapted from Legacy and emerging perfluoroalkyl substances are important drinking water contaminants in the Cape Fear River Watershed of North Carolina, by Sun et al., 2016 Environmental Science & Technology Letters, 3(12), 415-419.
From the diagram above, it is evident that GenX concentration is highest at point C (which is the source point of GenX compound). However, its level is insignificant at A and B (Which are the non-point source). From the map, Chemours which is the producing firm is located around point C. The company is shown in the diagram by the arrow labeled ‘Fluorochemical manufacturer.’ The graph indicates that the amounts of PFOA, PFOS and PFPrOPrA are higher than 600ng/L. This information is evidence that GenX remains to be the dominant pollutant in Cape Fear River.
In their study, Sun et al. (2016) examined three communities. These communities were labeled A, B and C. Community A and B were located at the different parts of the map above and along Cape Fear River. Society C, on the other hand, resided around the source of GenX. Statistically, region C harbors more than 250,000 North Carolina citizens. After obtaining samples from drinking water intakes in the three communities, the following results were obtained. See the graph below.
Figure 2. Concentration of GenX and other PFOS and PFOA in Communities A, B and C. Adapted from Adapted from Legacy and emerging perfluoroalkyl substances are important drinking water contaminants in the Cape Fear River Watershed of North Carolina, by Sun et al., 2016 Environmental Science & Technology Letters, 3(12), 415-419.
Once again, the statistical data showed that the GenX concentration was leading regarding parts per trillion. Therefore, statistical information suggests that the emission of GenX from Chemours possess a danger to both human beings and their surroundings. In response to the increasing insight into the effects of GenX on human life and the environment, a group from Chemours was sent to carry out research and write a report on the findings. The section below will examine the conclusions of the report.
RIVM Report
Beekman, Zweers, Muller, Janssen and Zeilmaker (2016) conduct research on the possible health effects of GenX on human beings and wrote the RIVM Report. According to the researchers, Chemours had developed a new technology in the manufacture of Teflon that eliminates PFOA in the process. This course of action followed the class-suit action that penalized the company billions of money. The new technology now makes GenX using three primary compounds namely E1, FRD-903, and FRD-902 (Beekman et al., 2016). The aim of the report was to evaluate the extent to which the three compounds would affect the people living near the manufacturing firm. In brief, the report identified that the new compounds were associated with similar effects to those of PFOA. However, the extent to which they affect human health is very low. They say that despite the fact that the compounds are poorly biodegradable, they do not accumulate in human bodies. To add weight to their hypothesis, they carried out several experiments on female and male rats in a controlled environment. The sole aim of this study was to examine the level of toxicity of the compounds. The following results were obtained.
Oral toxicity
Beekman et al. (2016) analyzed two studies that utilized rats and mice in a controlled environment. In both studies, the sample population was given different amounts of FRD-902 through gavage. The researchers administered 5000mg/Kg, 1750, 550 and 175 to diverse categories of female and male mice and rats. The entire study lasted for 14 days after which the observers necropsied the mice and rats.
From the experiment, the majority of female rats given 5000mg/Kg of FRD-902 died the same day. Two of the remainder died within one to two days after administration. After a close examination of these victims, it was noted that their liver, Mandibular nymph, and the lungs were discolored (Butenhoff et al., 2004). Similarly, the victims showed signs of hair loss, prostrate posture, clear ocular discharge, stained skin and fur, high position, salivation and partially closed eyes. Among the male rats, those in the group given 5000mg/Kg died. The members of the sample showed wet far, Lethargy, increased lung size, discolored eyes, and stomach as well as stained skin. However, the symptoms reversed on the second day. In the rest of the dosage groups, symptoms such as lethargy, wet fur, and stained skin were observed (Gannon et al., 2016).
Among the panel of mice, the entire samples in 5000 and 1750 mg/Kg died. They showed symptoms of low posture and lethargy. In all the other doses, there were signs of discolored lungs and cyst in the ovaries was observed in one mice. Other symptoms include non-specific lesions in some rats (Hoke et al., 2016).
From the results, we can conclude that FRD-902 has harmful effects such as increasing the lung size. We suppose that high concentration levels of the FRD-902 present in drinking water possess the same threat to human health. Similarly, the growth in organ size is undetermined. In the case where the compound induces cells to grow uncontrollably, it will result in severe conditions such as cancer. For such reasons, it is important to check the amounts of GenX concentration present in drinking water. The OECD classifies values greater than 1750 to be highly toxic concerning the experiment conducted above (IARC 2016).
Inhalation toxicity
The inhalation study was performed concerning OECD guidance number 403 (IARC 2016). The researchers separated the rats into three groups and exposed them to varying aerosol concentration. The different groups of mice were subjected to 5200, 100 and 13mg/Cubic meter of aerosol for four hours. The study period averaged 2-14 days after the exposure to the aerosol. After the appropriate period of study, the scholars conducted a microscopic analysis of the respiratory system tissues as well as a necropsy. The results showed stained faces, red discharge around the nose, mouth, and eyes among the rats in the 5200mg/cubic meter concentration group. Similar results of red nasal discharge were reported in rats subjected to 100 mg/m3 aerosol concentration. In this case, there was no death of the rats. The observable signs and symptoms reversed after two days. However, inhalation was associated with 2.5-6.8% decrease in body weight among rats in the highly concentrated group (Lau et al., 2007). Minor losses in weight were also observed in the other groups.
Dermal Toxicity
For the Dermal experiment, the research team used two rabbits for the study. The rabbits were then subjected to occlusive patches for one day. After 24 days, the experimenters washed off the concentrated reactant. The dose for this experiment was 5000mg/Kg. After the exposure to the occlusive patch, the rabbits did not die. However, the scholars identified cases of moderate to mild erythema. These observations reversed after ten days. Sloughing and epidermal scaling were also observed.
From the controlled study, it is evident that FRD-902 is corrosive to the skin in large quantities. However, the effect of the chemical on the skin can be reversed through washing with a lot of running water. In other studies, the compound is known to cause eye damage (Rae et al., 2015). According to OECD classification, the compound is classified under category 1 of eye-damaging agents (Hoke et al., 2016). The release of GenX byproducts into the air possesses a medical threat to human beings. However, the extent remains unknown since no available data focuses on the effects of FRD-902 on people.
Mutagenicity
From the study, Beekman and his colleagues confirmed that FRD-902 possessed insignificant effects on the genetic composition of the rats under study. However, at extremely high amounts of gavage administered to the rats, there was an alteration in the bone marrow of the rats but a still insignificant change in chromosomal aberration of the animals under study. Others died as a result of high volumes of FRD-902 (Beekman et al., 2016). Once again, mutagenicity in human beings remains unknown.
Carcinogenicity
The experimenters in this study utilized the OECD guideline 453 in performing the carcinogenicity experiment. A total of eighty rats were used in the controlled activity. From the study, it was noted that with time, the number of tumors increased variably in males and females. The table below represents the findings of the experiment.
Table 1. Tumor incidences related to FRD-902. Adapted from ‘Evaluation of substances used in the GenX technology by Chemours, Dordrecht’, by Beekman et al., 2016. RIVM rapport 2016-0174.
From the chart above, Hepatocellular adenoma in females increased from the historical 5% to 15.71% in rats in the highly concentrated group. Similarly, Hepatocellular carcinoma increased from old 1.7% to 5.71%. In males, pancreatic acinar cell adenoma decreased slightly from 5% to 4.29%. The other findings can be summarized from the table. However, despite the outcome, Beekman and his fellow researchers say that the carcinogenic properties observed are standard in rodents but not in human beings.
We can do it today.
Reproduction toxicity
In a control experiment, it was noted that FRD-902 caused early deliveries in rats. Similarly, there was decreased fetal mass at delivery ranging from 8.8%-28%. There was a decline in gravid uterine weight, hypertrophy as well as increased weight of the liver. In some cases, the parental animals increased their consumption habits and a hence significant increase in their body weight. Other observable effects on males were the delayed sexual maturation. However, the experts related the delay to the decrease in body weight and poor eating habits. There were no observable traits in the development of the offspring.
Organ toxicity
The following table summarizes the effects of weight gain/loss in the different organs.
Table 2. Tumor incidences related to FRD-902. Adapted from ‘Evaluation of substances used in the GenX technology by Chemours, Dordrecht’, by Beekman et al., 2016. RIVM rapport 2016-0174.
Presence of the GenX in drinking water possesses a great danger to human health. Scholars suggest that it may lead to accelerated puberty, the growth of cancerous cells, abnormal changes in cholesterol levels as well as liver and kidney damages (Rae et al., 2015). As a result of such increased tension among the members of the general public, authorities have intervened to address the issue. The section below examines the steps that different authorities have taken to ensure water safety as well as the elimination of GenX toxin in Cape Fear River.
What is being done?
The Imposing penalties to production firms
In the recent past, EPA has penalized DuPont and Chemours 680 million dollars for environmental pollution and emission of toxins into the Cape Fear River. This course of action will discourage the firm to discharge any more of GenX into the river. Similarly, other companies planning to participate in the production of Teflon chemicals will have the fear to dump their untreated waste into the river. In the long run, the Cape Fear River will be free from these toxins. Similarly, the action of imposing penalties on polluting firms will induce the companies to become more responsible for their actions. The production facilities will participate in preservation activities other than polluting. As a recommendation, the EPA and Cape Fear River Watch should set higher penalties for polluting firms.
Chemours have decided to remove and capture the contaminated water
Chemours have chosen to clean the contaminated water as well as end the dumping of GenX into the river. They have set a facility at Fayetteville that will screen the contaminated water and treat it before reaching the river. They also promised to pump out contaminated water that has a higher concentration than the recommended level (70ppt.).
Cape Fear River Watch
The Watch ensures the safety of drinking water retrieved from Cape Fear River. The agency has been educating the members of the public on the toxicity caused by GenX and other toxins as well as the possible treatment options. In their part, the Watch has decided to:
- Push for a binding agreement with the production company that they will end the dumping of their waste into Cape Fear River.
- Force DEQ to review the permits of local firms that give them a loophole to emit chemicals into the river. Currently, the Chemours permit is under consideration.
- The agency decided to advocate for transparency in the CFPUA so that the citizens will be notified of any toxins in time. No citizen should be kept in darkness especially on matters concerning their health.
- The Watch has decided to push the state to install facilities at the treatment plants that will eliminate particles of PFOS reported in Cape River water. Similarly, the state should focus on carrying out intensive research that seeks to reveal how much of the toxins are available at each water treatment plant.
Education on how to remove PFOS and PFOA in drinking water
EPA has recommended that system operators at the water treatment plants should assess water samples to determine the levels of PFOA and PFOS present (Chagawa, 2016). Any amount above 70 ppt. should be treated before it reaches the members of the public. The report recommended several treatment alternatives which include:
- River bank floatation
- Anion exchange
- Granular activated carbon (GAC)
- Microfiltration and
- Reverse osmosis
According to the report, Anion exchange was highly effective in removing PFOS from the water. However, it was moderately effective in the removal of PFOA. The method was unable to filter some shorter chain PFOS and PFOA. GAC proved to be an effective treatment alternative in many PFOA and PFOS. It is a less costly procedure and reliable. On the other hand, reverse osmosis and Nano filtration proved to be inept in treating even the short chain PFOA and PFOS from the drinking water.
With the current regulation and combined efforts from relevant authorities, the citizens who acquire drinking water from Cape Fear River can be assured of safe drinking water.
Conclusion
GenX is a close associate to C8 and other PFOA produced by DuPont and Chemours. This compound consists of shorter chains compared to the PFOA. Its chemical structure is abbreviated as PFPrOPrA (Sun et al., 2016). In the past one year, various studies show that GenX has similar health effects as the previous PFOA and PFOS (Lerner, 2017). These effects include accelerated puberty, the growth of cancerous cells, abnormal changes in cholesterol levels as well as liver and kidney damages. It is also closely associated with skin irritation and corrosion as well as carcinogenicity. Because of such potential health hazards, authorities have intervened to address the problem. Example of interventions includes educating the members of the public, Imposing penalties on polluting firms, Encouraging corporate social responsibility and Identifying technologies for treating water.
Examples of the most inept technologies to remove GenX compounds include Granular activated carbon, Nano filtration, River bank floatation, Anion exchange, Granular activated carbon (GAC), Microfiltration and Reverse osmosis (Appleman, 2013).
In a bid to ensure safe drinking water in North Carolina and other states in the USA, we request each treatment plant to test water samples and screen any traces of GenX, PFOS and other PFOA compounds. In the case where the particles presents exceed 70 ppt. The treatment facility should consider using any of the measures above to remove the toxins.
- Appleman, T. D. (2013). The removal of poly-and perfluoroalkyl substances by North American water treatment practices. Colorado School of Mines. 213-237.
- Beekman, J. M., Zweers, P., Muller, A., De Vries, W., Janssen, P., & Zeilmaker, M. (2016). Evaluation of substances used in the GenX technology by Chemours, Dordrecht. RIVM rapport 2016-0174. 3-17.
- Butenhoff, J. L., Kennedy G. L., Hindeliter P. M., Lieder P. H., Jung R, Hansen K. J., Gorman G. S., Nokr P.E. & Thonford P. J. (2004). Pharmacokinetics of perfluorooctanoate in cynomolgus monkeys. Toxicological Science series, 82, 394-406.
- Chagawa, P. (2016). How to Remove PFOA and PFOS from the Water. The New York Times. Retrieved from https://www.wateronline.com/doc/how-to-remove-pfoa-and-pfos-0001.
- EFSA (2008). Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and their salts. Scientific Opinion of the Panel on Contaminants in the Food chain, The EFSA Journal, 653: 1-131.
- Gannon, S.A., Fasano,W.J., Mawn, M.P., Nabb, D.L., Buck, R.C., Buxton,L.W., Jepson, G.W. & Frame, S.R. (2016). Absorption, distribution, metabolism, excretion, and kinetics of 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)propanoic acid ammonium salt following a single dose in rat, mouse, and cynomolgus monkey. Toxicology Science series, 340: 1-9.
- Gervois, P.N, Kleemann, R.J., Pilon, A.M., Percevault, F. N., Koenig, W., Staels, B. K., & Kooistra, T. (2004). Global Suppression of IL-6-induced Acute Phase Response GeneExpression after Chronicin VivoTreatment with the Peroxisome Proliferator-activated Receptor- Activator Fenofibrate. The Journal of Biological Chemistry 279 (16): 16154-16160.
- Guerra, P., Kim, M., Kinsman, L., Alaee, M., & Smyth, S. A. (2014). Parameters affecting the formation of perfluoroalkyl acids during waste water treatment. Journal of Hazardous Materials, 272, 148-154.
- Hoke, R.A., Ferrell, B.D., Sloman, T.L., Buck, R.C. & Buxton, L.W. (2016). Aquatichazard, bioaccumulation and screening risk assessment for ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate. Chemosphere 149: 336-342.
- IARC (2016). PerfluorooctanoicAcid, Tetrafluoroethylene, Dichioromethane,1,2-DichlorQpropane, and 1,3-Propane Sultone. In: IARC Monographsonthe Evaluation of Carcinogenic Risks to Humans, 110. 97(3), 714-728.
- Kannan, K. (2011). Perfluoroalkyl and polyfluoroalkyl substances: current and future perspectives. Environmental chemistry, 8(4), 333-338.
- Lau, C., Anitole, K., Hodes, C., Lai, D, P., fahles-Hutchens, A., Seed, J. (2007). Perfluoroalkyl Acids: A Review of Monitoring and Toxicological Findings. 99(2), 366-394.
- Lerner, S. (2017). New Teflon Toxin Present in North Carolina River. The Intercept. Retrieved From https://www.google.com/amp/s/static.theintercept.com/amp/new-teflon-toxin-found-in-north-carolina-drinking-water.html.
- McCleaf, P., Englund, S., Östlund, A., Lindegren, K., Wiberg, K., & Ahrens, L. (2017). Removal efficiency of multiple poly-and perfluoroalkyl substances (PFASs) in drinking water using granular activated carbon (GAC) and anion exchange (AE) column tests. Water Research, 120, 77-87.
- Post, G. B., Louis, J. B., Cooper, K. R., Boros-Russo, B. J., & Lippincott, R. L. (2009). Occurrence and potential significance of perfluorooctanoic acid (PFOA) detected in New Jersey public drinking water systems. Journal of Environmental science and technology, 43(12), 4547-4554.
- RAC(2011). Opinion proposing harmonized classification and labeling at Community level of Ammonium pentadecafluorooctanoate. EPA Document, 4(11), 506-519.
- Rae, J.M., Craig, L., Slone, T.W., Frame, S.R. Buxton, L.W., Kennedy, G.L. (2015). Evaluation of chronic toxicity and carcinogenicity of ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate in Sprague—Dawley rats. Toxicology Reports2: 939-949.
- Sun, M., Arevalo, E., Strynar, M., Lindstrom, A., Richardson, M., Kearns, B. & Knappe, D. R. (2016). Legacy and emerging perfluoroalkyl substances are important drinking water contaminants in the Cape Fear River Watershed of North Carolina. Environmental Science & Technology Letters, 3(12), 415-419.
- US-EPA (2016). Health effects support document for perfluorooctanoic acid. EPA Document Number: 822-R-16-003. 313-317.
- Yang, C.H., Glover,K.P., & Han, X. (2010). Characterization of Cellular Uptake of Perfluorooctanoate via Organic Anion-Transporting Polypeptide 1A2, Organic Anion Transporter 4, and UrateTransporter 1 for TheirPotential Roles in Mediating Human Renal Reabsorption of Perfluorocarboxylates. Toxicological sciences 117(2): 294-302.