one of the affected individuals; dupont, however, does not accept any liability from the toxicity of pfoa. while 3m sent dupont results from a study that showed birth defects to rats administered pfoa and dupont moved the women out of the teflon production unit, subsequent animal testing led dupont to conclude there was no reproductive risk to women, and they were returned to the production unit. however, data released in march 2009 on the community around dupont's washington works plant showed "a modest, imprecise indication of an elevation in risk ... above the 90th percentile ... based on 12 cases in the uppermost category", which was deemed "suggestive of a possible relationship" between pfoa exposure and birth defects. legal actions international action: stockholm convention pfoa was proposed for listing under the stockholm convention on persistent organic pollutants in 2015, and on may 10, 2019, pfoa, its salts, and pfoa-related compounds were added to annex a of the stockholm convention by the conference of the parties. several hundred salts and precursors of pfoa fall within the scope of the restriction. a few specific exemptions remained. among them is a time-bound exemption for pfoa in fire-fighting foam. industry and legal actions dupont has used pfoa for over 50 years at its washington works plant. area residents sued dupont in august 2001 and claimed dupont released pfoa in excess of their community guideline of 1 part per billion resulting in lower property values and increased risk of illness. the class was certified by wood circuit court judge george w. hill. as part of the settlement, dupont has paid for blood tests and health surveys of residents believed to be affected. participants numbered 69,030 in the study, which was reviewed by three epidemiologists—the c8 science panel—to determine if any health effects are the likely result of exposure. on december 13, 2005, dupont announced a settlement with the epa in which dupont would pay us$10.25 million in fines and an additional us$6.25 million for two supplemental environmental projects without any admission of liability. on september 30, 2008, chief judge joseph r. goodwin of the united states district court for the southern district of west virginia denied the certification of a class of parkersburg residents exposed to pfoa from dupont's facility because they did not "show the common individual injuries needed to certify a class action". on september 28, 2009, judge goodwin dismissed the claims of those residents except for medical monitoring. by 2015, more than three thousand plaintiffs have filed personal-injury lawsuits against dupont. in 2017, dupont reached a $670.7 million cash settlement related to 3,550 personal injury lawsuits tied to pfoa contamination of drinking water in the parkersburg area. chemours, which was spun off from dupont in 2015, agreed to pay half the settlement. both companies denied any wrongdoing. u.s. federal government actions in 2002, a panel of toxicologists, including several from epa, proposed a level of 150 ppb for drinking water in the pfoa contaminated area around dupont's washington works plant. this initially proposed level was much higher than any known environmental concentration and was over 2,000 times the level epa eventually settled on for the drinking water health advisory. in july 2004, epa filed a suit against dupont alleging "widespread contamination" of pfoa near the parkersburg, west virginia plant "at levels exceeding the company's community exposure guidelines;" the suit also alleged that "dupont had—over a 20 year period—repeatedly failed to submit information on adverse effects (in particular, information on liver enzyme alterations and birth defects in offspring of female parkersburg workers)." in october 2005, a usfda study was published revealing pfoa and pfoa precursor chemicals in food contact and ptfe products. on january 25, 2006, epa announced a voluntary program with several chemical companies to reduce pfoa and pfoa precursor emissions by the year 2015. on february 15, 2005, epa's science advisory board (sab) voted to recommended that pfoa should be considered a "likely human carcinogen". on may 26, 2006, epa's sab addressed a letter to administrator stephen l. johnson. three-quarters of advisers thought the stronger "likely to be carcinogenic" descriptor was warranted, in opposition to epa's own pfoa hazard descriptor of "suggestive evidence of carcinogenicity, but not sufficient to assess human carcinogenic potential". on november 21, 2006, epa ordered dupont to offer alternative drinking water or treatment for public or private water users living near dupont's washington works plant in west virginia (and in ohio), if the level of pfoa detected in drinking water is equal to or greater than 0.5 parts per billion. this measure sharply lowered the previous action level of 150 parts per billion that was established in march 2002. according to a may 23, 2007, environmental science & technology online article, u.s. food and drug administration research regarding food contact papers as a potential source of pfoa to humans is ongoing. in november 2007, the centers for disease control and prevention (cdc) published data on pfoa concentrations comparing 1999–2000 vs. 2003–2004 nhanes samples. on january 15, 2009, epa set a provisional health advisory level of 0.4 ppb in drinking water. on may 19, 2016, epa lowered the drinking water health advisory level to 0.07 ppb for pfoa and pfos. in june 2022 the agency issued updated advisories, stating that "some negative health effects may occur with concentrations of pfoa or pfos in water that are near zero and below epa's ability to detect at this time." epa also issued new health advisories for genx and pfbs. in march 2021 epa announced that it will develop drinking water standards for pfoa and pfos in public water systems. in october 2021 the epa proposed to designate pfoa and pfos as hazardous substances in its pfas strategic roadmap. in september 2022 the epa proposed to designate as hazardous substances under the superfund comprehensive environmental response, compensation, and liability act of 1980 (cercla). new jersey in 2007 the new jersey department of environmental protection (njdep) announced that it found pfoa at "elevated levels in the system's drinking water near dupont's massive chambers works chemical plant". in 2018 the state published a drinking water standard for pfna. public water systems in new jersey are required to meet a maximum contaminant level (mcl) standard of 13 ppt. in 2019 new jersey filed lawsuits against the owners of two plants that had manufactured pfass (the chambers works and the parlin plant in sayreville), and two plants that were cited for water pollution from other chemicals. the companies cited are dupont, chemours and 3m. in 2020 the njdep set a pfoa standard at 14 ppt and a pfos standard at 13 ppt. new york in 2018 the new york state department of health adopted drinking water standards of 10 ppt for pfoa and 10 ppt for pfos, effective in 2019 after a public comment period. michigan in november 2017, the michigan pfas action response team (mpart) was created to address growing pollution concerns after multiple sites contaminated by pfas were identified. mpart is a multi-agency team tasked with investigating pfas contamination sites and sources in the state, protecting drinking water, enhancing interagency communication and keeping the public informed. in january 2018, michigan established a legally enforceable groundwater cleanup level of 70 ppt for both pfoa and pfos. two science advisory committees were also created and joined mpart to "coordinate and review medical and environmental health, pfas science and develop evidence-based recommendations". in august 2020, the michigan department department of environment, great lakes, and energy adopted stricter drinking water standards in the form of mcls, lowering acceptable levels from the 2018 enforceable groundwater cleanup levels of 70 ppt to 8 ppt for pfoa and 16 ppt for pfos and adding mcls for 5 previously unregulated pfas compounds pfna, pfhxa, pfhxs, pfbs, and hfpo-da. minnesota in 2007, the minnesota department of health lowered its health based value for pfoa in drinking water from 1.0 ppb to 0.5 ppb, where "the sources are landfilled industrial wastes from a 3m manufacturing plant". european action pfoa contaminated waste was incorporated into soil improver and spread on agricultural land in germany, leading to pfoa drinking water contamination of up to 0.519 parts per billion. the german federal environmental agency issued guidelines for the sum of pfoa and pfos concentrations in drinking water: 0.1 parts per billion for precaution and 0.3 parts per billion for a threshold. residents were found to have a 6–8 factor increase of pfoa serum levels over unexposed germans, with average pfoa concentrations in the 22–27 parts per billion range. an expert panel concluded that "concentrations were considered too low to cause overt adverse health effects in the exposed population". in the netherlands, after questions by members of parliament, the minister of environment ordered a study into the potential exposure to pfoa of people living in the vicinity of the dupont factory in dordrecht. the report was published in march 2016 and concluded that "prior to 2002 residents were exposed to levels of pfoa at which health effects could not be ruled out". as a result of this, the government commissioned several further studies, including blood tests and measurements in drinking water. pfoa was identified as a pbt substance in the eu in 2013. it was then included in the candidate list of substances of very high concern. in 2017, pfoa, its salts and pfoa-related substances were added to annex xvii (restriction) of the reach regulation. the eu adopted the listing of pfoa in annex a of the stockholm convention with commission delegated regulation (eu) 2020/784 of 8 april 2020 and introduced a limit value of 0,025 mg/kg for pfoa including its salts, and at 1 mg/kg for the individual pfoa-related compounds or a combination of those compounds. they also included some specific exemptions. among them is a time-bound exemption for pfoa in fire-fighting foam. australian action on august 10, 2016, australian litigation funder imf bentham announced an agreement to fund a class action led by the law firm gadens against the australian department of defence for economic losses to homeowners, fishers, and farmers resulting from the use of aqueous film forming foam (containing pfoa) at raaf base williamtown.