Waiting to Die: Toxic Emissions and Disease Near the Louisiana Denka/DuPont Plant

Frequently Asked Questions    about our health study

Frequently Asked Questions about our health study



Three years ago, residents living near a chemical plant in St. John the Baptist Parish, Louisiana were told by the Environmental Protection Agency (EPA) that they faced the highest risk in the country of developing cancer from air pollution.

St. John Parish is part of an area of Louisiana known as “Cancer Alley,” an 85-mile stretch of land along the Mississippi River between New Orleans and Baton Rouge. More than 150 chemical plants and oil refineries dot this stretch of land, where most communities are predominantly Black and many residents attribute seemingly staggering levels of cancer and other illness to toxic air emissions from industry.[1]

Listen to Their Stories.

The St. John plant’s neoprene manufacturing unit—owned by DuPont until its sale to Japanese company Denka Performance Elastomer[2] in November 2015—has been pumping the toxic chemical chloroprene into a predominantly Black community since 1969. Residents had long felt that there was too much illness in the area—far beyond what could be considered normal. One resident with whom we spoke recalled the words of her niece, shortly before she passed away of cancer: “We’re just sitting here, waiting to die.”

The EPA’s 2011 National Air Toxics Assessment (NATA), released in December 2015, seemed to confirm many residents’ suspicions. According to the most recent NATA, the risk of developing cancer from air pollution in the census tract closest to the Denka neoprene facility is nearly 50 times the national average due to emissions of chloroprene,[3] classified by the EPA as a “likely human carcinogen.” The EPA advocates a significant reduction in chloroprene emissions from the Denka facility, such that air concentration of the chemical does not exceed 0.2 micrograms per cubic meter (µg/m³)—the maximum concentration that would keep cancer risk from air pollution within the EPA’s “upper limit of acceptability.”[4]

More on cancer alley and the denka/dupont plant

For the past three years, community members have demanded a reduction of chloroprene emissions to this EPA-recommended maximum level of 0.2 µg/m³. Their struggle for environmental justice has gained increasing traction and national media coverage.[5]

Although the EPA has affirmed its confidence in the scientific validity of its chloroprene assessment—stating that the assessment “was developed using a robust, transparent, and public process and represents the Agency’s top tier source of toxicity information on chloroprene”[6]—Denka continues to challenge the EPA’s findings on chloroprene toxicity.[7]

Denka signed a voluntary agreement to reduce emissions in January 2017 and finished installing emissions reduction technology by the end of that year, but the EPA’s air monitoring data continues to show high levels of chloroprene emissions—well in excess of the 0.2 µg/m³ guideline—in the neighborhoods around the Denka facility.

COncerned citizens confront denka in japan

This report by the University Network for Human Rights presents localized health data from the area surrounding the Denka/DuPont plant. In March 2018, a team of trained researchers collected health data from a large sample of residents who live within 2.5 kilometers of the plant. Below, we present our in-depth analysis of this household health survey data. Our data reveal extremely improbable rates of cancer and other illness among residents surveyed. We also found that prevalence of cancer and other illness among our survey sample is correlated with proximity to the Denka plant, with higher rates of illness closer to the plant.

Cancer prevalence among those surveyed is unusually high. Among respondents (those who provided health information about themselves and all their household members), the p-value for cancer prevalence when compared to a distribution of populations with the same race, sex, and age demographics is 0.6% (very statistically significant).[8] In other words, the probability of the 9.7% cancer prevalence outcome that we found among respondents—the likelihood that we would see a cancer prevalence this high or higher in a population with the same race, sex, and age composition—is only 0.6%.

Among all residents surveyed (respondents plus all their household members, i.e. everyone for whom we collected information), the p-value for cancer prevalence is 3.43% (statistically significant).

Cancer prevalence among those surveyed is also associated strongly with proximity to the Denka facility. The p-value for cancer prevalence among respondents who live closest to the facility (within 1.5 kilometers) is 0.26% (very statistically significant). The p-value for cancer prevalence among residents who live closest to the facility (within 1.5 kilometers) is 0.33% (very statistically significant).

Prevalence of non-cancer health conditions associated with chloroprene exposure is also striking and invariably correlated with proximity to the plant. Nearly half the children in the households surveyed within 1.5 kilometers of the plant suffer from headaches, nosebleeds, or both. P-values for tachycardia (abnormally fast heart rate) diagnosed by a doctor or other health care provider are 0% for both respondents and residents, indicating a virtual impossibility that high tachycardia prevalence among the survey sample was due to chance.

Among respondents surveyed within 1.5 kilometers of the plant: nearly 40% regularly experience chest pain, heart palpitations, or both; one-third regularly experience wheezing and/or difficulty breathing; more than half regularly experience headaches, dizziness, and/or lightheadedness; nearly half regularly experience eye pain/irritation and/or watery eyes; more than 40% experience cough, sneezing, and/or sore/hoarse throat most of the time; more than one-third regularly experience skin rash/irritation and/or itchy skin; and nearly 30% experience fatigue/lethargy most of the time.

Overall, our findings strongly indicate that prevalence of cancer and other illness among residents surveyed is unusually high compared to what we would expect using national actuarial tables. These results are disturbing enough to warrant additional in-depth, localized, and rigorous health studies in the area surrounding the Denka/DuPont plant and throughout Cancer Alley.

In the meantime, local, state, and federal agencies—including the Louisiana Department of Environmental Quality and the Louisiana Department of Health—must insist that Denka Performance Elastomer adhere to the EPA’s 0.2 µg/m³ guideline for maximum chloroprene air concentration.

[1] Trymaine Lee, Cancer Alley: Big Industry, Big Problems, MSNBC, http://www.msnbc.com/interactives/geography-of-poverty/se.html.

[2] Denka Co. Ltd. owns 70% of Denka Performance Elastomer, and Mitsui Co. Ltd. owns 30%.

[3] United States Environmental Protection Agency, 2014 National Air Toxics Assessment, https://www.epa.gov/national-air-toxics-assessment/2014-national-air-toxics-assessment.

[4] Memorandum from Kelly Rimer to Frances Verhalen, Preliminary Risk-Based Concentration Value for Chloroprene in Ambient Air, United States Environmental Protection Agency (May 5, 2016), https://www.epa.gov/sites/production/files/2016-06/documents/memo-prelim-risk-based-concentrations050516.pdf.

[5] See, e.g., Sharon Lerner, When Pollution is a Matter of Life and Death, New York Times (June 22, 2019), https://www.nytimes.com/2019/06/22/opinion/sunday/epa-carniogens.html; Jamiles Lartey and Oliver Laughland, ‘Almost every household has someone that has died from cancer,’ The Guardian (May 6, 2019), https://www.theguardian.com/us-news/ng-interactive/2019/may/06/cancertown-louisana-reserve-special-report; Rebecca Hersher, After Decades of Air Pollution, A Louisiana Town Rebels Against A Chemical Giant, NPR (Mar. 6, 2018), https://www.npr.org/sections/health-shots/2018/03/06/583973428/after-decades-of-air-pollution-a-louisiana-town-rebels-against-a-chemical-giant; Victor Blackwell et al., Toxic tensions in the heart of ‘Cancer Alley,’ CNN (Oct. 20, 2017), https://www.cnn.com/2017/10/20/health/louisiana-toxic-town/index.html.

[6] Memorandum from John Vandenberg to Wren Stenger, EPA’s Integrated Risk Information System (IRIS) Assessment of Chloroprene, United States Environmental Protection Agency (May 25, 2016), https://www.epa.gov/sites/production/files/2016-06/documents/memo-iris-chloroprene052516.pdf.

[7] Letter from Koki Tabuchi to Scott Pruitt, Request to Withdraw and Correct the 2010 IRIS Review of Chloroprene (June 26, 2017), https://www.scribd.com/embeds/408326975/content?start_page=1&view_mode=scroll&access_key=key-pMd8zNOfLwIOotdRyQXN&show_recommendations=false.

[8] P-values are generally expressed as decimals rather than percentages (0.006 rather than 0.6%, for example). Throughout this report, we express p-values as percentages because they are conceptually easier for the layperson to understand this way. P-values less than 5% (0.05) are considered statistically significant.






地域住民は過去3年間、EPAが推奨する最大値0.2 µg/m³への低減を求めてきました。彼らの環境正義を求める闘いは勢いを増し、全米のマスメディアが報道し始めました。[4]



University Network for Human Rights(UNHR)作成の本レポートには、デンカ・デュポン工場周辺地域で採取された局所的な健康データが提示されています。2018年3月、専門的訓練を受けた研究者から成るチームが、同工場から2.5キロ以内に住む住民の大型サンプルから健康データを採取しました。以下に、世帯健康調査データの詳細な分析を示します。このデータから、調査の対象となった住民のがん等の罹病率が極めてありえない数字だったことが分かります。さらにこの調査によって、本調査サンプルに見られるがん等の有病率は、デンカ工場からの距離と相関しており、工場に近ければ近いほど罹病率が高いことも明らかになりました。

調査対象者のがん有病率は異常に高いのです。調査回答者(自分のほか、世帯構成員全員の健康情報を提供した対象者)のがん有病率のp値は、同じ人種、性別、年齢層の分布と比較すると0.6%(統計的に非常に有意)となります。[7] 調査回答者のがん有病率が9.7%となる結果が出る確率、つまり人種、性別、年齢層の分布が同じ人口でこれと同等またはさらに高いがん有病率がみられる可能性は、わずか0.6%なのです。






と同時に、ルイジアナ州の環境基準省や保健省を含む、地域・州・連邦レベルの各機関は、EPAが示したクロロプレンの大気中最大濃度0.2 µg/m³ガイドラインを遵守するよう、デンカ・パフォーマンス・エラストマー社に対して要求し続ける必要があります。

[1] Trymaine Lee、Cancer Alley「がん回廊―大きな産業の大きな問題」MSNBC、http://www.msnbc.com/interactives/geography-of-poverty/se.html.

[2] 米国環境保護庁、2014年度国家大気有害物質評価、 https://www.epa.gov/national-air-toxics-assessment/2014-national-air-toxics-assessment.

[3] Kelly RimerからFrances Verhalenに宛てた覚書「大気中クロロプレンの予備的リスクベースの濃度」、米国環境保護庁(2016年5月)https://www.epa.gov/sites/production/files/2016-06/documents/memo-prelim-risk-based-concentrations050516.pdf.

[4] 例としてSharon Lerner「汚染が生死に関わるとき」ニューヨークタイムズ(2019年6月22日)https://www.nytimes.com/2019/06/22/opinion/sunday/epa-carniogens.html; Jamiles Lartey、Oliver Laughland、「ほとんどすべての世帯で誰かががんによって死去」ガーディアン(2019年5月6日)https://www.theguardian.com/us-news/ng-interactive/2019/may/06/cancertown-louisana-reserve-special-report; Rebecca Hersher何十年にもわたる大気汚染の末、ルイジアナの町が化学産業の巨人に反発、NPR (2018年3月6日)https://www.npr.org/sections/health-shots/2018/03/06/583973428/after-decades-of-air-pollution-a-louisiana-town-rebels-against-a-chemical-giant; Victor Blackwell他、「がん回廊」の真ん中で有害な緊 CNN (Oct. 20, 2017年10月20日)https://www.cnn.com/2017/10/20/health/louisiana-toxic-town/index.html.

[5] John VandenbergからWren Stengerに宛てた覚書、「EPAの統合リスク情報システム(IRIS)によるクロロプレン評価」米国環境保護庁(May 25, 2016年5月25日)https://www.epa.gov/sites/production/files/2016-06/documents/memo-iris-chloroprene052516.pdf.

[6] 田渕浩記からScott Pruittに宛てた書状「2010年度クロロプレンIRISレビューの撤回・修正のお願い」(2017年6月26日)https://www.scribd.com/embeds/408326975/content?start_page=1&view_mode=scroll&access_key=key-pMd8zNOfLwIOotdRyQXN&show_recommendations=false.

[7] 一般にP値は百分率でなく小数(たとえば0.6%でなく0.006)で表されますが、本報告では一貫してp値を百分率で表しています。そのほうが一般の人にその概念を理解してもらいやすいからです。なお5%(0.05)未満のp値は統計的に有意とされます。