Many organic compounds are known to cause cancer in animals; some are suspected of causing, or are known to cause, cancer in humans.

Harmful VOCs typically are not acutely toxic, but have compounding long-term health effects.

Because the concentrations are usually low and the symptoms slow to develop, research into VOCs and their effects is difficult.

VOCs in the air, water, and land.

Biologically generated VOCs[edit]
Not counting methane, biological sources emit an estimated 1150 teragrams of carbon per year in the form of VOCs.[15] The majority of VOCs are produced by plants, the main compound being isoprene. The remainder are produced by animals, microbes, and fungi, such as molds.

The strong odor emitted by many plants consists of green leaf volatiles, a subset of VOCs. Emissions are affected by a variety of factors, such as temperature, which determines rates of volatilization and growth, and sunlight, which determines rates of biosynthesis. Emission occurs almost exclusively from the leaves, the stomata in particular. A major class of VOCs is terpenes, such as myrcene. Providing a sense of scale, a forest 62,000 km2 in area (the US state of Pennsylvania) is estimated to emit 3,400,000 kilograms of terpenes on a typical August day during the growing season. VOCs should be a factor in choosing which trees to plant in urban areas.

Anthropogenic sources

Anthropogenic sources emit about 142 teragrams of carbon per year in the form of VOCs.

Specific components

Paints and coatings
A major source of man-made VOCs are coatings, especially paints and protective coatings. Solvents are required to spread a protective or decorative film. Approximately 12 billion litres of paints are produced annually. Typical solvents are aliphatic hydrocarbons, ethyl acetate, glycol ethers, and acetone. Motivated by cost, environmental concerns, and regulation, the paint and coating industries are increasingly shifting toward aqueous solvents.[20]

Chlorofluorocarbons and chlorocarbons
Chlorofluorocarbons, which are banned or highly regulated, were widely used cleaning products and refrigerants. Tetrachloroethene is used widely in dry cleaning and by industry.

Fossil fuels
The use of fossil fuels produces VOC's either directly as products (e.g., gasoline) or indirectly as byproducts (e.g., automobile exhaust gas).[citation needed]

Benzene
Main article: Benzene
One VOC that is a known human carcinogen is benzene, which is a chemical found in environmental tobacco smoke, stored fuels, and exhaust from cars. Benzene also has natural sources such as volcanoes and forest fires. It is frequently used to make other chemicals in the production of plastics, resins, and synthetic fibers. Benzene evaporates into the air quickly and the vapor of benzene is heavier than air allowing the compound to sink into low-lying areas. Benzene has also been known to contaminate food and water and if digested can lead to vomiting, dizziness, sleepiness, rapid heartbeat, and at high levels, even death may occur.[citation needed]

Methylene chloride
Methylene chloride can be found in adhesive removers and aerosol spray paints. In the human body, methylene chloride is metabolized to carbon monoxide. If a product that contains methylene chloride needs to be used the best way to protect human health is to use the product outdoors. If it must be used indoors, proper ventilation will help to keep exposure levels down.[citation needed] In the United States, methylene chloride is listed as exempt from VOC status.

Perchloroethylene
Perchloroethylene is a volatile organic compound that has been linked to causing cancer in animals. It is also suspected to cause many of the breathing related symptoms of exposure to VOCs.[citation needed] Perchloroethylene is used mostly in dry cleaning. While dry cleaners recapture perchloroethylene in the dry cleaning process to reuse it, some environmental release is unavoidable.

MTBE
MTBE was banned in certain states within the US around 2004 in order to limit further contamination of drinking water aquifers (groundwater) primarily from leaking underground gasoline storage tanks where MTBE was used as an octane booster and oxygenated-additive.[citation needed]

Formaldehyde
Many building materials such as paints, adhesives, wall boards, and ceiling tiles slowly emit formaldehyde, which irritates the mucous membranes and can make a person irritated and uncomfortable. Formaldehyde emissions from wood are in the range of 0.02–0.04 ppm. Relative humidity within an indoor environment can also affect the emissions of formaldehyde. High relative humidity and high temperatures allow more vaporization of formaldehyde from wood-materials.

Indoor air
Main article: Indoor air quality
Since many people spend much of their time indoors, long-term exposure to VOCs in the indoor environment can contribute to sick building syndrome. In offices, VOC results from new furnishings, wall coverings, and office equipment such as photocopy machines, which can off-gas VOCs into the air. Good ventilation and air-conditioning systems are helpful at reducing VOCs in the indoor environment. Studies also show that relative leukemia and lymphoma can increase through prolonged exposure of VOCs in the indoor environment.

In the United States, there are two standardized methods for measuring VOCs, one by the National Institute for Occupational Safety and Health (NIOSH) and another by OSHA. Each method uses a single component solvent; butanol and hexane cannot be sampled, however, on the same sample matrix using the NIOSH or OSHA method.

The aromatic VOC compound benzene, emitted from exhaled cigarette smoke, is labeled as carcinogenic and is ten times higher in smokers than in nonsmokers.

EPA has found concentrations of VOCs in indoor air to be 2 to 5 times greater than in outdoor air and sometimes far greater.[14] During certain activities indoor levels of VOCs may reach 1,000 times that of the outside air. Studies have shown that individual VOC emissions by themselves are not that high in an indoor environment, but the indoor total VOC (TVOC) concentrations can be up to five times higher than the VOC outdoor levels.[29] New buildings especially, contribute to the highest level of VOC off-gassing in an indoor environment because of the abundant new materials generating VOC particles at the same time in such a short time period. In addition to new buildings, we also use many consumer products that emit VOC compounds, therefore the total concentration of VOC levels is much greater within the indoor environment.

VOC concentration in an indoor environment during winter is three to four times higher than the VOC concentrations during the summer. High indoor VOC levels are attributed to the low rates of air exchange between the indoor and outdoor environment as a result of tight-shut windows and the increasing use of humidifiers.

Indoor air quality measurements
Measurement of VOCs from the indoor air is done with sorption tubes e. g. Tenax® (for VOCs and SVOCs) or DNPH-cartridges (for carbonyl-compounds). The VOCs adsorb on these materials and are afterwards desorbed either thermally (Tenax®) or by elution (DNPH) and then analyzed by GC-MS/FID or HPLC. Reference gas mixtures are required for quality control of these VOC-measurements.[32] Furthermore, VOC emitting products used indoors, e. g. building products and furniture, are investigated in emission test chambers under controlled climatic conditions.[33] For quality control of these measurements round robin tests are carried out, therefore reproducibly emitting reference materials are ideally required.

Regulation of indoor VOC emissions
In most countries, a separate definition of VOCs is used with regard to indoor air quality that comprises each organic chemical compound that can be measured as follows: Adsorption from air on Tenax TA, thermal desorption, gas chromatographic separation over a 100% nonpolar column (dimethylpolysiloxane). VOC (volatile organic compounds) are all compounds that appear in the gas chromatogram between and including n-hexane and n-hexadecane. Compounds appearing earlier are called VVOC (very volatile organic compounds); compounds appearing later are called SVOC (semi-volatile organic compounds). See also these standards: ISO 16000-6, ISO 13999-2, VDI 4300-6, German AgBB evaluating scheme, German DIBt approval scheme, GEV testing method for the EMICODE. Some overviews over VOC emissions rating schemes[34] have been collected and compared.

France, Germany and Belgium have enacted regulations to limit VOC emissions from commercial products, and industry has developed numerous voluntary ecolabels and rating systems, such as EMICODE, M1, Blue Angel and Indoor Air Comfort[38] In the United States, several standards exist; California Standard CDPH Section 01350[39] is the most popular one. Over the last few decades, these regulations and standards changed the marketplace, leading to an increasing number of low-emitting products: The leading voluntary labels report that licenses to several hundreds of low-emitting products have been issued (see the respective webpages such as MAS Certified Green.- Certified Products).

Health risks

Respiratory, allergic, or immune effects in infants or children are associated with man-made VOCs and other indoor or outdoor air pollutants.

Some VOCs, such as styrene and limonene, can react with nitrogen oxides or with ozone to produce new oxidation products and secondary aerosols, which can cause sensory irritation symptoms. Unspecified VOCs are important in the creation of smog.

Health effects include eye, nose, and throat irritation; headaches, loss of coordination, nausea; and damage to the liver, kidney, and central nervous system. Some organics can cause cancer in animals; some are suspected or known to cause cancer in humans. Key signs or symptoms associated with exposure to VOCs include conjunctival irritation, nose and throat discomfort, headache, allergic skin reaction, dyspnea, declines in serum cholinesterase levels, nausea, vomiting, nose bleeding, fatigue, dizziness.[citation needed]

The ability of organic chemicals to cause health effects varies greatly from those that are highly toxic, to those with no known health effects. As with other pollutants, the extent and nature of the health effect will depend on many factors including level of exposure and length of time exposed. Eye and respiratory tract irritation, headaches, dizziness, visual disorders, and memory impairment are among the immediate symptoms that some people have experienced soon after exposure to some organics. At present, not much is known about what health effects occur from the levels of organics usually found in homes. Many organic compounds are known to cause cancer in animals; some are suspected of causing, or are known to cause, cancer in humans.

https://en.wikipedia.org/wiki/Volatile_organic_compound

Water - it's impurities, gathered from the air and earth.

Air

- T he air, then, is the carrier of the myriads of microscopic germs , which have so large an in
fluence in the production of human maladies. They lie in wait for opportunityto exercise their
baneful purposes, needing only heat and moisture, or any form of decaying or putrefying substances for fructification.

- Surgeon s recognize the danger of allowing atmospheric air to penetrate into wounds or the
interior of the human organism, lest it be loaded with pathogenic germs.

- It has been estimated that a single cubic inch of Space will contain germs of aver
age size. They increase by fission
,
at the rate of one
division every hour. Hence a single one becomes
the parent of every 24 hours. and the
causative parent of in that length of time.
A very interesting investigation has been instituted
near Paris for estimatin g the microbes in atmospheric
air
, and an ingenious trap continually set to catch
them. A cubic metre of air in the laboratory is
found to contain on an average 53 0microbes
, while a
cubic metre ofair in the central part of the city con
tains in the sewers in Old houses 40,
000
, and in the old Hospital of Pitie
, of Paris.

Source: Water - it's impurities, gathered from the air and earth. The organisms that grow in it and the modern methods of purification. Author: O.W.Moore, M.D., 

Pollution and cancer in Chinese villages and cities

Summary:

High cancer rates are not just a rural phenomenon. Cancer is actually more common in cities, and the media has reported on this. The reason for paying attention to cancer villages is that, in cities, the social safety net is much stronger – healthcare and other resources are concentrated in urban areas and, if there’s a problem, it is easier to get help.
(source: https://www.chinadialogue.net/article/show/single/en/4098-The-shadow-over-rural-China)

1. Typical polluting factories - chemicals, pharmaceutical, fertilizers, power


 Families in Yanglingang, which is surrounded by pharmaceutical and chemical plants, claim they live in a 'cancer village' as deaths rise above the national average. Photograph: Lu Guang/Greenpeace

2. Cancer mortality rates in China have risen 80% over the past 30 years, making it the country's leading cause of death.

3. In cities, toxic air is a primary suspect; in the countryside, it's the water.

4. More than 70% of the country's rivers and lakes are polluted, according to government reports, almost half may contain water that is unfit for human contact.

5. "Fundamentally, the situation isn't getting any better," said Liu Lican, a Guangzhou-based journalist who has published a book about cancer villages. Pollution-related cancer, he said, can elude detection for years. "So even if the cancer was caused by pollution that's already gone, maybe gradually more and more of these villages will emerge."

6. My observation: Polluted water does not only cause cancer, but also causes auto-immune disorders! Likely, from the note/photo of the Gaurdian below. The dramatic increase in the number of auto-immune disorders in the recent times is also an indication of the fact the people are not drinking the right water.  Perhaps, even diabetes is some form of auto-immune disease. So, even diabetes may be caused due to water. 

In 2011, the three-month nephew of Xie Zhengqing, pictured collecting fishing nets with Xie Zhengwei, 28, died of a rare autoimmune disease. Photograph: Jonathan Kaiman for the Guardian


 In 2011, the three-month nephew of Xie Zhengqing, pictured collecting fishing nets with Xie Zhengwei, 28, died of a rare autoimmune disease. Photograph: Jonathan Kaiman for the Guardian

7. Yanglingang lacks a public water supply, and before the government built the industrial zone in the early 2000s, the villagers didn't mind; the river was clean, its fish abundant. But for eight years, Yanglingang has been sandwiched between the Nine Dragons paper mill and a power plant that billows white smoke from four tall stacks, covering the houseboats in a thin layer of ash. The mill discharges its waste water directly into the Yangtze, leaving a maroon residue on the rocks along its shoreline.

8. Villagers purify the water with alum powder before drinking it, but even well-treated batches carry a faint industrial aftertaste. "Everybody here has some form of illness," Xie said. His mother is bedridden with bronchitis. His infant nephew died of Evans syndrome, which has no known cause but is not usually fatal. The family took out £7,000 in loans to pay for the baby's medical expenses, and Xie doubts that they will ever be repaid.

9. Despite abundant anecdotal evidence for China's profusion of cancer villages, scientific proof has been elusive. When Wu Yixiu, toxics campaigner at Greenpeace East Asia, first visited Yanglingang in 2010, she assumed that establishing a causal connection between its pollution and cancer problems would be fairly straightforward – its population is so tiny, the disease so widespread, the pollution so caustic. "It's unimaginable that their health will not be affected by the quality of this water," she said.

10. Yet there are too many specific chemicals involved and too many types of cancer; diagnoses are spread over too many years. "You need to establish the fact that it's a certain chemical that's causing certain cancers, and this chemical is being discharged from this very factory," she said. "This would require years of observation and tracing disease records."

11. About 140 miles south of Yanglingang, in a far-flung suburb of Hangzhou City, 45-year-old Wei Dongying has spent almost two decades trying to build a similar case. Pollution has haunted Wuli village, population 2,000, since the nearby Nanyang chemical industry zone opened its doors in 1992, gradually covering its waterways with black streaks and soapy-white froth.

"So many people here have gotten cancer, they want answers, but they've been given nothing," said Wei.


Xu Changlian and his wife, Wang Jinnan, pictured in 2010, have cancer, the exact causes of which are unknown. Photograph: Lu Guang/Greenpeace

12. Between 1992 and 2004, 60 villagers died of cancer, Wei said. Last year, it killed another six. Wei keeps samples of tainted village water in a corner of her three-storey tiled house and stacks of fraying documents – petitions, official letters, test results – in thick manila envelopes on her shelves.

When she complained to national environmental authorities in 2004 – she had already tried local petitioning – the municipal government promised to shut down Nanyang's polluting factories within three years. Yet the industrial zone continues to operate unimpeded. Wuli's water still frequently runs black; on some days the air smells like burning refuse.

13. Government-approved researchers have visited Wuli, but most seem keen to debunk Wei's claims. "They say the number of deaths isn't too high," she said. "I say, wait until someone in your family gets cancer, then tell me it's not too high." They have tested the water, but refuse to publicise their results. After Wuli received a flurry of media attention in early April, local authorities threatened residents with unspecified consequences for their outspokenness.

14. Villages such as Dongxing, in Jiangsu province – a four-hour drive north from Yanglingang – are often left to fend for themselves. The Julong chemical plant, which villagers, academic studies and media reports suspect gave more than 100 residents cancer between 2000 and 2005, sits abandoned on the village's southern limits, but its impact may linger for decades. Northern winds sometimes carry a vague chemical scent which villagers say emanates toxic waste buried near the factory ruins. Streams that once coursed through the village have long run dry.Chinese media and academics have discussed Dongxing's cancer rate since 2006, when a reporter for the China Economic Times investigated the plant, which produced 2,000 tonnes a year of the carcinogenic chemical chlorophenol a year. After Julong opened in 2000, the village's ducks, chickens and geese began dying en masse.

Villagers slept with wet towels over their mouths and noses, terrified of inhaling toxic fumes. Air around the elementary school, 300 metres from the factory, smelled so noxious that villagers moved their children to one in a neighbouring township.

Shu Qichang sits in a white-brick farmhouse flanked by verdant rice paddies, fanning himself in the April heat, weary from heart disease. His eyes are shockred, his cheeks sallow. Petitioning was useless, he said. The county environmental bureau denied the cancer rate was a problem, and the town courthouse would not hear their case.

Thugs detained the farmers near a higher court in Funing County and followed them to the highest provincial court in Nanjing – where the lawsuit was ultimately discarded.

Then in 2010, without giving a reason, the factory closed.

****

Chinese government investigates 'cancer village' pollution case

15. Authorities launch enquiry into illegal pollution from Chuangyuan Aluminium plant, alleged to have caused more than 10 cancer deaths in rural Hunan province.


 View of aluminum-polluted water, which flows into the Yuanjiang River, in Taoyuan county, Changde city, central China’s Hunan province. Photograph: Dong Mu/Imagine China/Corbis

16. Chinese authorities have begun investigating a shocking case of industrial pollution in central China’s Hunan province, in which runoff from an aluminium plant’s illegal landfill allegedly gave at least 10 local villagers cancer.

Pollution from the plant, operated by the Changsha-based aluminium products manufacturer Chuangyuan Aluminium Co Ltd., had made parts of the remote rural county of Taoyuan virtually uninhabitable, the government-run Beijing News reported on Sunday.

17. The Sunday report in the Beijing News said that the factory’s aluminium production created highly toxic fluoride runoff, which seeped into the Yuan River, a tributary of the Yangtze; villagers then used the water to irrigate their crops. Pictures on the newspaper’s microblog showed eddies of coffee-coloured water, dusty shrubs with purple-stained leaves, and billowing smokestacks towering over a quiet residential street.

“These have all changed,” one unnamed villager told the newspaper, pointing up at a tangerine tree. “These were originally just tangerines, and then one by one, their skin developed all these little tumours.”

Another villager told the paper: “More than 10 people have died of cancer, one after the other. And a lot of people have become weak — they feel achy and powerless, but check-ups can’t identify any diseases.”

****
China's reliance on coal reduces life expectancy by 5.5 years, says study

18. High levels of air pollution will cause 500 million people to lose an aggregate 2.5 billion years from their lives.


Heavy smog shrouds Beijing with pollution at hazardous levels. Photograph: Feng Li/Getty Images

19. Air pollution causes people in northern China to live an average of 5.5 years shorter than their southern counterparts, according to a study released on Monday which claims to show in unprecedented detail the link between air pollution and life expectancy.

High levels of air pollution in northern China – much of it caused by an over-reliance on burning coal for heat – will cause 500 million people to lose an aggregate 2.5 billion years from their lives, the authors predict in the study, published in the journal the Proceedings of the National Academy of Sciences.

The geographic disparity can be traced back to China's Huai River policy which, since it was implemented between 1950 and 1980, has granted free wintertime heating to people living north of the Huai river, a widely-acknowledged dividing line between northern and southern China. Much of that heating comes from the combustion of coal, significantly impacting the region's air quality.

"Using data covering an unusually long timespan – from 1981 through 2000 – the researchers found that air pollution … was about 55% higher north of the river than south of it," the MIT Energy Initiative said in a statement.

"Linking the Chinese pollution data to mortality statistics from 1991 to 2000, the researchers found a sharp difference in mortality rates on either side of the border formed by the Huai River. They also found the variation to be attributable to cardiorespiratory illness, and not to other causes of death."

The researchers, based in Israel, Beijing, and the Massachusetts Institute of Technology, gauged the region's air quality according to the established metric of "total suspended particulates (TSP)," representing the concentration of certain airborne particles per cubic meter of air.

The study concluded that long-term exposure to air containing 100 micrograms of TSP per cubic meter "is associated with a reduction in life expectancy at birth of about 3.0 years."

20. Air pollution has been the subject of widespread public outrage in China since January, when Beijing's air quality index (AQI) – a similar metric to TSP – regularly exceeded 500, the scale's maximum reading, for weeks on end. On 12 January, Beijing's AQI hit a record 755, 30 times higher than levels deemed safe by the World Health Organisation.

Past studies have established a link between air pollution and reduced life expectancy. One recent large-scale study concluded that air pollution contributed to 1.2 million premature deaths in China in 2010.

Yet according to Michael Greenstone, an economics professor at MIT and one of the study's authors, this study is the first to precisely quantify their relationship. "Demonstrating that people die a bit earlier [because of pollution] is interesting and helps establish that pollution is bad," he said. "But the most important question, the next question that needed to be answered, is what's the loss of life expectancy? How much should society be willing to pay to avoid high levels of pollution? This study was structured so we could answer that question."

****
The shadow over rural China

In 2008, Liu Lican visited 20 “cancer villages” in 20 provinces at his own expense, seeing at first hand the villages that have been sickened by rapid economic development and environmental degradation. He has turned his experiences into a book, China’s Cancer Villages, as yet unpublished. Here, Liu talks to chinadialogue’s Zhang Yingying about his findings.

22. ZY: Is industrial pollution the main reason for high cancer rates in these locations? And how are those cancer villages distributed?

LL: Industrial pollution is seen as the main culprit in most cancer villages, and the ones that I visited were no exception. I say “is seen as” because you need a lot of evidence to say for sure that the problems are caused by industrial pollution. We can only say that, in many villages, the main suspicion is that factory pollution has caused an increase in cancer and other diseases.

Nationwide, we can see some patterns in cancer villages. Most appeared in the mid to late 1990s and are much more frequently found in eastern and central China than in the west – most likely this is positively correlated with economic development. However, the numbers in the eastern and central regions are fairly equal.

23. ZY: Why do these high incidences of cancer happen in villages? How does this compare with cities?

LL: High cancer rates are not just a rural phenomenon. Cancer is actually more common in cities, and the media has reported on this. The reason for paying attention to cancer villages is that, in cities, the social safety net is much stronger – healthcare and other resources are concentrated in urban areas and, if there’s a problem, it is easier to get help.

Another issue is that, when villages are polluted, in particular by factories owned by outside investors, or by the treatment of urban waste in the countryside, the villagers receive no compensation for the harm incurred. And in recent years, we have seen industry shift from the coast inland and from cities to villages, and so the harm done to rural areas has been worsening.

24. ZY: In these cancer villages, the villagers don’t sue on the basis of damage to their health, but for direct economic losses. Why is that?

LL: The relationship between pollution and disease is complex and hard to prove, and that gives government and business an excuse. Meanwhile, the villagers see that some of them get ill, while others stay healthy – and so it is also hard for them to judge the situation. The impact of industrial pollution on crops, livestock, fields, fish and buildings is easier to identify and determine, while damage to the human body is hidden. Compensation for the economic losses is hard enough to come by – suing for damage to health would be even harder.

Another issue is that, when villages are polluted, in particular by factories owned by outside investors, or by the treatment of urban waste in the countryside, the villagers receive no compensation for the harm incurred. And in recent years, we have seen industry shift from the coast inland and from cities to villages, and so the harm done to rural areas has been worsening.

****

25. "Our villages are so polluted that everybody wants to move. The rich have already moved."

26. Pan Xiaochuan, a professor at Peking University’s School of Public Health, believes environmental factors in general contribute to more than 50 percent of cancer cases. But he stressed that when it comes to specific cases, it’s hard to make a direct link between chemicals and cancer.

“It depends on the specific pollutants, as well as on how people are actually exposed to them,” Pan said in an interview with Sixth Tone.

He added that a lack information on pollutants and diseases in China is also an issue because it becomes difficult to know for sure just who or what is responsible for health issues without empirical data.

“That’s why polluters and those accused of causing illness can always defend themselves — because there’s no evidence,” Pan said.

Sources:

https://www.theguardian.com/world/2013/jun/04/china-villages-cancer-deaths

https://www.theguardian.com/environment/2014/dec/10/chinese-government-investigates-cancer-village-pollution-case

https://www.chinadialogue.net/article/show/single/en/4098-The-shadow-over-rural-China

Too Little, Too Late for Polluted Yangtze River Towns?

Villagers on the banks of China’s longest river blame polluting industries for health woes.

Shi Yi

May 24, 2016

Along a stretch of the Yangtze River not far from Yichang City in the central Chinese province of Hubei, the air was once fragrant with ripening citrus fruit.

Today, with all the nauseating fumes from a nearby fertilizer plant, people prefer to stay shut inside their homes, insulated from the outside world by closed windows and doors.

“Our village is so polluted that everybody wants to move,” Zou Changxin, a 66-year-old resident told Sixth Tone in an interview. “The rich have left here already, and only poor people like me remain.”

In January, on a visit to the metropolitan area of Chongqing, on the Yangtze in western China, President Xi Jinping announced a blueprint for development that in the future will quell industrial projects along the river. The plan also details measures for restoring the river’s ecology, including water quality and biodiversity.

Environmentalists have long complained of threats to the river’s ecosystem coming from pollution as well as from extensive damming, such as by The Three Gorges Dam, which is located north of Yichang.

Xi’s speech was seen as a turning point for China’s decades-long policy to promote economic development at all costs. If implemented, the policy would mean no more industrial parks in close proximity to the Yangtze. Steps would also be taken to ensure any growth would be sustainable, the policy document stated, offering some residents and non-governmental organizations hope of a greener future.

But for some Chinese people, including many in Yichang, the change of policy should have happened a long time ago.

Women dance on a quiet street, with chimneys visible in the background, Yichang, Hubei province, April 17, 2016. Shi Yi/Sixth Tone

Zou lives in Xiaoting, a suburb of Yichang, through which the Yangtze flows on its path from the Tibetan highlands to the sea near Shanghai, a journey of more than 6,000 kilometers. His small, drab two-story house lies just a few hundred meters from the banks of the river. Three decades ago, Zou could look out from his house and enjoy an unimpeded view of the water. Now he finds himself surrounded by factories.

Many residents, including Zou, blame the rise of polluting industries in the area for a host of recently diagnosed illnesses, including cancer. In 2014 he was diagnosed with cancer of the bladder. Since then Zou has undergone surgery twice, leading to the removal of his bladder. Today, Zou has to carry a urine drainage bag around, and says that many of his neighbors have already died from the disease. 

This is a situation that occurs with such regularity around China that it’s hard to put a figure on the number of so-called cancer villages. Like many other parts of the country, this corner of Yichang has been rapidly gobbled up by economic development. The location’s proximity to the Yangtze and the logistical possibilities the relatively flat land offers are seen by local government officials as key advantages for promoting economic development.

Though it is not uncommon for residents to blame heavy industry for spikes in cancer-related deaths, it is difficult to show a definitive link between factories and illnesses. This is mainly due to a lack of hard data, but it’s also due to an unwillingness among some government officials to draw too much attention to the downside of rapid economic growth. Government officials typically say that factories in these industrial parks contribute to the local economy by creating jobs and paying taxes.

Gong Shengsheng, a professor in the School of Urban and Environmental Science at Central China Normal University in Wuhan, Hubei province, has plotted 396 “cancer villages,” reported by media and NGOs from 1980 to the end of 2015, on a map of China. His study verified that more than 95 percent of these villages were affected by hazardous chemicals. Gong declined to share more specific data with Sixth Tone, citing the data’s “sensitivity to authorities.”

A rare example of an official document acknowledging the existence of such villages came to light in 2013. The document, issued by the Ministry of Environmental Protection, pointed to pollution as the underlying cause of cancer villages in certain areas. The same document said that an investigation of China’s chemical, petroleum, and pharmaceutical companies in 2010 showed that around 15,000 such factories are close to residential areas — a situation the document said posed health and safety risk to humans.

Official data from the Xiaoting Health and Family Planning Commission only includes rates of diabetes, psychosis, and hypertension, as required by the national commission. The data shows no clear differences between local and national data.

Both the Xiaoting District government and the Yichang municipal government said none of the residents had come to them voicing concerns about cancer.

Yu Wanlin, a retired leader in Xiamacao Village, told Sixth Tone that in the past, local residents welcomed the arrival of heavy industry, and people were less concerned about the environment. “It was a sign of development,” he said.

In this part of Yichang, residents claim they can trace the origin of their health problems to the arrival of one company in particular: Hubei Yihua Chemical Industry Co. Ltd. Established in 1977, Yihua is the oldest company in the area — it set up in an area that would later become part of the Yichang Economic Development Zone — and is a division of Hubei Yihua Group, a state-run enterprise that owns the largest fertilizer manufacturing plants in China, according to data from the Chemical Industry and Engineering Society of China.

In 2004, Yihua gave assurances that one of their then-soon-to-be-added factories would be environment friendly. “No one questioned the project,” Yu recalls. “But the fact is, the anti-pollution measures haven’t been as effective as the company said they would be.”

Official documents from Yichang’s environmental protection bureau show that waste from some of Yihua’s factories includes sulfur dioxide, ammonia nitrogen, and other pollutants. Inspection reports Yihua provided to Sixth Tone state that waste discharged from their factories in recent years has met the national standard.

But villagers don’t feel comforted by words on paper: It’s hard for them to ignore the strong odor that envelopes the area more often than not.

A view of a sulfuric acid dump site in use and owned by Hubei Yihua Chemical Industry Co. Ltd., Yichang, Hubei province, April 18, 2016. Shi Yi/Sixth Tone

Residents still living in the shadow of the factories remember one incident in September 2006, when sulfur dioxide leaked from a plant in which Yihua holds a 50 percent stake.

Sulfur dioxide is a gas that occurs naturally in the environment. It is also generated by burning fossil fuels and is a byproduct of certain industrial processes. According to the U.S. Environmental Protection Agency, exposure to highly concentrated forms of the gas for any length of time can be harmful to one’s health, causing respiratory illnesses or exacerbating existing cardiovascular diseases. Exposure can also trigger cancer.

On the day of the leak, a thick black cloud of smoke drifted from the plant toward settlements nearby, sending screaming residents from their homes. According to a report by state news agency Xinhua, 184 people sought treatment at a nearby hospital for severe headaches and other symptoms.

Zou has a gas mask issued by Yihua to him and other residents after the accident. He still keeps it inside its dust-covered packaging, never having used it. “As long as I live here, there’s no way to run away from the toxins,” he said.

China’s laws require chemical factories to keep a certain distance — usually a kilometer — from residential areas. To adhere to this requirement, there have been pushes to relocate residents. But the pace of expansion of the Yichang industrial park has been faster than the speed with which local residents have been relocated.

According to the district government, a total of 1,075 households still live within a kilometer of the factories. Of which, only 394 families have already been relocated. Many who have been moved to new apartments farther from the industrial park say they are happy to keep the pollution at arm’s length.

But one 55-year-old man who still lives a few hundred meters away from the Yihua factory and who would only give his surname, Zhao, said: “Usually after the local environmental protection bureau or the company receives our complaints and brings inspectors here, nothing happens. The dirty air doesn’t just go away.”

Yang Xiaohong, the press officer of the Xiaoting District government, said there are official plans to relocate all residents by 2018.

A factory owned by Hubei Yihua Chemical Industry Co. Ltd., next to the Yangtze River at Yichang, Hubei province, April 18, 2016. Shi Yi/Sixth Tone

Yao Jianhua of the Chinese Center for Disease Control and Prevention in Suzhou, in the eastern province of Jiangsu, has studied the effects of long-term exposure to low concentrations of ammonia, another chemical commonly found in plants that produce fertilizers and other chemicals, on workers. Yao’s study showed that workers who were in close contact with ammonia experienced respiratory and skin diseases, among other symptoms, at a much higher frequency than the control group.

Pan Xiaochuan, a professor at Peking University’s School of Public Health, believes environmental factors in general contribute to more than 50 percent of cancer cases. But he stressed that when it comes to specific cases, it’s hard to make a direct link between chemicals and cancer.

“It depends on the specific pollutants, as well as on how people are actually exposed to them,” Pan said in an interview with Sixth Tone.

He added that a lack information on pollutants and diseases in China is also an issue because it becomes difficult to know for sure just who or what is responsible for health issues without empirical data.

“That’s why polluters and those accused of causing illness can always defend themselves — because there’s no evidence,” Pan said.

Additional reporting by Fu Danni.

(Header image: Smoke billowing from chimneys at an industrial park in Yichang, Hubei province, April 17, 2016. Shi Yi/Sixth Tone)