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Soil Pollution in China

September 11, 2015 | All Grades
By Galeet Cohen

The farmlands surrounding this tile factory in Dingshu are no longer suitable for growing crops because of heavy metal contamination. Image by Wu Di. China, 2014.

A farmer planting rice in Hunan Province's You County, where high levels of cadmium and lead have been found in the soil. Image by He Guangwei for Yale Environment 360. China, 2014.

A chemical factory beside a rice paddy in Yixing in Jiangsu Province, where industrial pollution has contaminated soil and crops. Image by Mark Ralston for AFP/Getty Images. China, 2014.

Chemical plants in the village of Zhoutie in Central China's Jiangsu Province have polluted waterways and contaminated locally produced rice and wheat with cadmium. Although the government has closed the worst of the factories, toxins remain in the soil. Image by Wu Di. China, 2014.

Wastewater from the Xiangtan Pigment Chemical Company poured into the Xiang River in September 2011, after what company officials said was an equipment failure at their plant. Image by Li Feng for Yale Environment 360. China, 2014.

Villagers in Zhoutie, where these farmlands surround a chemical plant, believe pollution is the cause of rising cancer rates there. When crops like rice and wheat are grown in soil contaminated with heavy metals, the grain absorbs the toxins. Image by Wu Di. China, 2014.

This steel rolling mill in Hengyang in Hunan Province empties its wastewater into the Xiang River. Local residents say the company operates at night in order to avoid inspection. Image by Li Fen for Yale Environment 360. China, 2014.

Nearly 3,000 factories were built along Lake Tai in the last two decades, with chemical plants proliferating in the agricultural area where Yixing, Zhoutie, and Fenshui are located. Map by Aaron Reiss/Yale Environment 360.

Industrial pollution has contaminated the soil of Shuangqiao and affected the drinking water supply for 20 million people, including the residents of Changsha, a city with a population of 2.1 million. Map by Aaron Reiss for Yale Environment 360.

The government has been reluctant to acknowledge the scale of the problem in Zhoutie, where soil has been contaminated with heavy metals discharged by chemical plants like this one. Image by Wu Di. China, 2014.

Chromium refineries in Hengyang in Hunan Province have dumped their untreated slag waste into this pit, less than 500 meters from the Xiang River. Image by Li Fen for Yale Environment 360. China, 2014.

Environmental activist Wu Lihong, shown here in a 2011 photo, led the opposition in Yixing township to the industrial pollution of Lake Tai and served a four-year prison sentence. He remains subject to restrictions and is forbidden to talk to the media. Image by Mark Ralston. China, 2011.

Heavy metal pollution caused by factories like this one in Jiangsu Province has contaminated vast tracts of China's arable land. Officials say cleanup costs nationwide could reach $1.6 trillion. Image by Li Feng for Yale Environment 360. China, 2014.

Residents of Dingshu were unaware that rice produced there was found to contain cadmium levels more than twice that allowed by China's food safety standards. Image by Wu Di. China, 2014.

Yixing is the center of the glazed ceramics industry, which makes products such as these pots ready for shipment in Dingshu. Waste dumped by the industry is a major contributor to the area's soil pollution. Image by Wu Di. China, 2014.

Essential Questions:

  1. What is the cost of industrialization and who pays it?
  2. How do we determine whether food is safe?
  3. How do you balance food security (production) and food safety?

Warm-up:  

1. What is your favorite meal that involves rice? Describe it. (pair or class discussion)

2. How much rice do you think you eat per year? Use measuring cups, electronic balances and rice samples to come up with an estimate.  You may want different students/groups to describe their method of estimation.  Calculate a class average and compare to global data.

http://irri.org/images/rice_today/12-1-rice-facts2.jpg

3. Make a list of nutrients you expect to be present in rice and their functions.

4. Make a list of things you would not expect to be in your rice in significant quantities.

*You may make this into a competition and have groups compare their lists to the nutrition labels on several rice packages.

Introducing the Lesson:

Let students know that they are about to read a series of articles about an element that should not be present in significant quantities in rice, but is becoming problematic in one region.

Introducing Resource 1: "China’s Dirty Pollution Secret: The Boom Poisoned Soil and Crops"

Objective: Develop a broad understanding of the problem, identify the stakeholders, notice how the journalist engages the reader and develops their understanding throughout the article.

1. As you read this first article in a series about soil contamination in China, underline and annotate the article to focus on the most important aspects of the story. Then use the QAD to bring out the main ideas and details used to support those ideas.  (QAD document at end of document)

2. Work in a small group (2-4 people) to first discuss and then complete the ‘further analysis’ section. Be prepared to share your responses with the entire class.

Introducing Resource 2: "In China's Heartland, a Toxic Trail Leads from Factories to Fields to Food"

Objective: Draw a diagram illustrating the flow of pollution from factories to consumers. Identify opportunities for intervention throughout the diagram.

1. Read the second article. Notice that it states that ‘Cao still does not understand exactly how the rice came to be contaminated with cadmium’. This second activity is designed to help him and others like him out.  

2. In pairs, draw a diagram illustrating the origin(s) of cadmium, it’s flow through the environment, and exposure to humans. The diagram can either be intended for a technical audience or intended for the general public (this may depend on your art skills).

Diagrams should include the following items:

  • Non-ferrous metal mines→ wastewater → rice field irrigation

  • Non-ferrous metal mines→ wastewater → watershed contamination → rice field irrigation

  • Non –ferrous metal mines→ solid tailings→(escape to) soil contamination

  • Farmer→ national grain reserve (granary) → rice trader → mill/packager → consumer

3. Pass your diagram to another group, review their diagram and add opportunities for intervention in any place within your diagram that seems appropriate. Put a star next to any cleanup attempt that is referenced in the article- giving it a number on your diagram and the same number in the article. Add any additional ideas for clean-up or prevention to your diagram, but leave off the star.

Introducing Resource 3: "The Soil Pollution Crisis in China: A Cleanup Presents Daunting Challenge"

Objective: Identify considerations in cleaning up an incidence of soil/water contamination. Quantitatively describe an event or conflict.

When bad things happen, how do we let others know how bad they are? What kind of numbers might be helpful in really communicating the magnitude of this problem?

Discussion Questions:

  1. What evidence exists that contamination within the community occurred?
  2. Why is contamination still likely to happen even after the factory shuts down?
  3. What was the government’s response to the problem?
  4. How appropriate or successful was the government’s response to the contamination event?
  5. What options do villagers have?
  6. What does it mean for the site to be clean? Is it?

By the Numbers (worksheet attached)

1. Pick out 5 numbers reported within the story that you think best summarize the issue.  Annotate the number with an explanation of what it represents.  

Extension:

Option 1.  Think carefully about how to present your numbers in terms of order, arrangement on a page, font size. Then turn your numbers and annotations into a full-page visual display. Inspiration) http://www.sewweekly.com/2012/01/the-sew-weekly-in-numbers/

Option 2. Try to summarize the article without using any numbers or data at all. You must attempt to convey the information contained within your 5 chosen quanities from the table without using any actual numbers. Read your article aloud to the class and compare it with the original.

Extension Activities:

I. Advanced Biology, Environmental Science, Biochemistry

Explore (Jigsaw): (worksheet attached)

Use the resources available at http://www.atsdr.cdc.gov/csem/csem.asp?csem=6&po=0 .

Students will investigate one subtopic relating to cadmium toxicity, taking their own notes.  They will meet with experts from their own group the next day to clarify their own understanding of cadmium toxicity and then with students from other groups so that each topic is represented.  Upon completion of information sharing, they will take the posttest provided by the CDC and/or discuss a medical case study.

Posttest

Case Study

II. Math, Environmental Science

1. Explain LD50.

https://www.youtube.com/watch?v=flKJ5Iqfl9Q

http://www.ccohs.ca/oshanswers/chemicals/ld50.html

2. If the acute lethal dose is 20-30 mg/kg of body weight (based on data from the UK Health Protection Agency), what would be a good estimate of a lethal dose for you based on your body weight? Show calculations.

3. Make a list of reasons your estimate might differ from the true value. Consider as many complicating factors as possible.

4. Lets apply this to the real situation:

  • Why do you think it is so hard to determine a true lethal dosage to report to folks such as those in China regularly being exposed?

Further Resources:

Cadmium toxicity:

Cadmium in drinking water:

Name _____________________________________________ Period ________ Date ___________

QAD: "In China's Heartland, a Toxic Trail Leads from Factories to Fields to Food"

Question Answer (concise, main idea) Detail (statistics or information from the article that support the answer)
What economic shift did China go through in the 1990s? Industrialization Factories built along lakeshores, new roads and highways, taller buildings, higher wages and prosperity
What problem are some rice farmers in China experiencing?    
Why is rice contaminated?    
What is the magnitute of the contamination? (How bad is it?)    
What are the health consequences of rice contamination?    
What are the environmental consequences of rice contamination?    
What are the economic consequences of rice contamination?    
What are some solutions being explored?    

Further Analysis:

1. How does the author engage the reader in this issue? Is their approach successful? Why or why not?

2. Rank the solutions being attempted from best to worst. Then explain why you are more impressed with some approaches than others.

3. Imagine the perspective of the various stakeholders involved in this issue.  Choose 2 and write a quote you imagine they might give if you interviewed them about their thoughts on this article.

  • Government (Ministry of Env Protection)
  • Government (Ministry of Land)
  • Farmers
  • Public (rice consumers)
  • Villager who had been employed at a small heavy-metal smelting factory

Names __________________________________________________________________________________________  Period __________  Date ________________________

How does rice become contaminated with cadmium?: "In China's Heartland, a Toxic Trail Leads from Factories to Fields to Food"

1. Read the article paying special attention to the flow of cadmium (Cd) through the environment.  Underline and take notes where necessary. Then draw a diagram illustrating the origin(s) of Cd, it’s flow through the environment, and exposure to humans. The diagram can either be intended for a technical audience or intended for the general public.

2. Exchange diagrams with another group.  Review their diagram and add opportunities for intervention (taking action to improve a situation) in any place within your diagram that seems appropriate. Put a star next to any cleanup attempt that is referenced in the article- giving it a number on your diagram and a corresponding # on your copy of the article. Add your own ideas for clean-up or prevention to your diagram, but leave off the star.

Name _________________________________________________________________ Period ________ Date __________________

By the numbers: How do we quantify problems and solutions?: The Soil Pollution Crisis in China: A Cleanup Presents Daunting Challenge

1. Pick out 5 numbers reported within the story that you think best summarize the issue. Circle them within your copy of the article, then write the notable numbers on the left side of the table below and annotate them with an explanation of what it represents.  

2. (Extra Credit) Think carefully about how to present your numbers in terms of order, arrangement on a page, font size. Then turn your numbers and annotations into a full-page visual display like an infographic. Inspiration:

The Sew Weekly

A Few Limbach Highlights

Quantity

Reason that it is important
 

 

5

 

 

This is the quantity of notable numbers you need to pull from the article to summarize the magnitude of cadmium contamination and clean up efforts.  Be sure to include UNITS when appropriate.  

 

  

 

  

 

  

 

  

 

  

Name _______________________________________________ Period _____ Date __________

Homework (Jigsaw):  Become a medical expert on cadmium toxicity.

You will become an expert on a particular aspect of cadmium toxicity using a course designed for primary care providers. Circle the topic that you are responsible for researching tonight. Then use the space below to take notes. You will meet with experts in other groups tomorrow to put your knowledge together. Use the given resources as starting points in your investigation.

All topics can be found in the green menu on the left-hand side of this page.

  • Cadmium
  • Where Found
  • Exposure Pathways
  • Safety Standards
  • Who is at Risk
  • Biological Fate
  • Pathogenic Changes
  • Acute Effects
  • Chronic Effects
  • Risk Factors

Notes:

Educator Notes: 

This lesson contains notes for both students and the facilitator.

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