Welcome Authors!

Dr. D fearlessly contemplates leaving
the pavement in lower King's Canyon NP.

Welcome, San Diego Pollution Trackers, to your spring 2021 blog.    This weblog is the public face of the University of San Diego's spring 2021 environmental chemistry class (Chem 355).  It will keep you in the know about our experimental results, with a San Diego focus.  You will also find links to info about current events, discoveries, and research questions that relate to the topics in this course.

To see earlier posts from the USD's 2014 and 2012 environmental chemistry classes, scroll down!

Contamination, drought, and turmoil

In March, I attended the 247^th National Meeting of the American Chemical Society with my research group to present our research on DNA hairpins.  The most interesting symposium I attended discussed careers in environmental sciences, put on by the Younger Chemists Committee.  One of the speakers was Charlie F. Anderson, the immediate past president of the American Water Works Association.  Mr. Anderson, a chemist by education, had worked in the public utilities of Arlington, TX for more than 30 years.  During his talk, Mr. Anderson stressed that access to a clean municipal water supply is one of the pillars of the developed world and asked us to imagine what would happen to our society if our cities’ water supplies suddenly vanished.  Chaos, he stressed, would ensue within days.

A hauntingly similar situation played out in early January 2014 when a chemical spill into a river in Charleston, West Virginia left about 300,000 people without access to potable water.  The incident occurred after up to 28,000 liters of a chemical foaming agent leaked into the Elk River, one mile upstream from a water treatment plant which serves the Charleston metro area in a region nicknamed Chemical Valley.  The foaming agent, 4-Methylcyclohexylmethanol (MCHM) is used to treat coal to produce “coke,” a high-carbon fuel with few impurities.  This supercoal is often used in iron production and can be used both as a fuel as well as a reducing agent.  Little is known about the toxicity of MCHM, but within two days, 700 residents had called the state’s poison control center, and 122 people had sought treatment for nausea and vomiting.  After a week, most of the affected area was officially allowed to use its water again, after flushing their plumbing.  The situation in West Virginia is far from over, and it happened in one of the worst possible areas in the country in terms of its immediate financial impact on average citizens.  West Virginia is the third poorest state in the US, and more than 17 percent of West Virginians fall under the poverty line.  Months later, thousands still live without running water, not trusting the okay given by state officials.  As a result, these already struggling families are spending significant portions of their incomes on bottled water and disposable items.

Chemical Structure of 4-Methylcyclohexylmethanol, the chemical that contaminated the Elk River in January. Source: wikimedia.org

Contamination by both chemicals and bacteria is probably the most well-known water issue.  Water.org claims that most of the 3.4 million yearly water-related deaths are caused by fecal matter contamination and reports that worldwide, more people have cell phones than toilets.  These problems are of critical importance, but at least there is some hope for improvement.  With economic development and aid by NGOs and foreign governments, the situation will hopefully improve with time.  However, there exists another water problem that manifests itself in a much more dramatic manner with a less hopeful future.  In Showtime’s currently-airing environmental documentary series Years of Living Dangerously, Thomas Friedman of the New York Times investigates the link between drought and recent political instability in the Middle East.  Between 2006 and 2010, four consecutive droughts ravaged Syria, forcing more than one million people to leave their farming villages and move to the cities, and forced up to three million people into extreme poverty.  The lack of aid by the Syrian government outraged many.  Friedman claims that while not a main cause for the March 2011 Syrian Civil War, the drought and subsequent mass poverty and migration likely contributed to the political unrest and may have played a role in pushing the situation over the edge.  Indeed, a confidential US diplomatic cable from before the revolution warned of mass migrations in Syria due to the drought, and predicted that the dire climate would “throw the entire country into chaos.”  

Access to clean water is clearly poised to become one of the world’s most important issues as the earth continues to warm.  Implementing sanitation infrastructure in developing regions as well as preventing future West Virginia-style contamination are extremely important missions.  However, taking actions to decrease the effect of climate change and increasingly frequent droughts may end up being the defining water issue for future generations hoping to avoid the “chaos” that Charlie F. Anderson warned about.

Further Reading

"Chemical Valley", by Evan Osnos in the April 7th issue of The New Yorker

Years of Living Dangerously - "Climate Wars with Thomas L. Friedman"

Water...A human right that is becoming harder to come by

We know that about seventy percent of the world is covered in water, but the World Health Organization has reported other statistics that are not as well known. Each year, 3.575 million people die from water-related diseases. Forty-three percent of those deaths are due to diarrhea, including 1.5 million children under the age of five. These numbers translate to about 4900 deaths every day or one child every fifteen seconds. About one billion people lack access to safe water, which is approximately eighteen percent of the global population. By the year 2025, it is estimated that one third of the global population will face severe and chronic water shortages.  It is also well known that humans rely on water for survival. Although it may not be well known that water makes up more than two-thirds of the weight of the human body; the brain is seventy-five percent water, blood is eighty-three percent water, muscles are seventy-five percent water, and the lungs are ninety percent water.

Clearly, water is something that all people need.  It is a component that humans understand as necessary to life, but still it is not safely available to all people. These statistics are hard to accept, but thankfully, this global problem has been scientifically confronted. Both biological and chemical contamination are worldwide problems that are being tackled with many different techniques, but economic viability of these techniques is essential.

A person needs 13.2 gallons/day of water for drinking, sanitation, and hygiene, yet even though there is so much water in the world and water is vital to human life, the average person in a developing country uses a mere 2.64 gallons/day. The average person in the United Kingdom uses 35.66 gallons/day. The average person in the United States uses 100-175  gallons/day. Water purification in developing countries at an affordable cost is essential.

This article describes six innovative water purification techniques that have been implemented in developing countries http://inhabitat.com/6-water-purifying-devices-for-clean-drinking-water-in-the-developing-world/.

I think that most these techniques, except for two (the “pure” water bottle that filters water with UV rays and the hamster ball-shaped Solarball) seem affordably implementable. Of the other four viable techniques, I find the Lifestraw most interesting but would like to know more about how it operates specifically. It would also be nice to know the cost and efficacy of each of these techniques in order to assess which option is best in helping aid the world water sanitation issue.

Water Quality and BOD

Pollution from fertilizer runoff increases levels of nutrients such as phosphate and nitrate in water, causing algae to bloom and increase the amount organic material in the water. Once decomposition of algae and other organics such as dead plants, sewage and food waste begins, large amounts of dissolved oxygen are used up in the process, creating "dead zones" in the water where lack of oxygen decreases potential for life of fish, plants and other water creatures. Dissolved Oxygen (DO) levels can be tested to determine the biological oxygen demand (BOD), which is a measure of the amount of oxygen that is consumed resulting from the decomposition of organic material in water. We tested BOD levels by comparing DO values of water in Tecolote Creek over a five day period.

Figure 1. Relation between BOD Level and Water Quality.

Figure 2. Map showing BOD Level at each tested site in Tecolote Canyon.

Figure 3. BOD levels related to percent organic content in sediment. 

Results displayed in Figure 1 show that about half of the sites in tested Tecolote Canyon lie in the category of "Very Good" water supply, another four are moderately clean, while sites near USD and Mt. Etna were measured to be poorly polluted on account of their BOD level. The correlation between BOD level and percent organic that would be expected can be observed for the most part in Figure 3 where a higher levels of organics in the sediment correspond with a high BOD, except for at sites SN1 and CH which show the opposite. 

Thankfully, for the most part Tecolote Creek did not exhibit measurable problems with dissolved oxygen. Many sites were actually found to contain clean water upon assessment. The site with the highest BOD was located near the creek outlet, which suggests that pollution was caused due to runoff from sites further upstream. Even with these hopeful results, we should not remain ignorant to the situation. We did prove that a higher organic content would increase the BOD and so measures must still be taken to limit the amount of organic waste that we allow to escape into our water. 

Future "Dead Zones" in Mission Bay

       We continued our wonderful adventure of exploring and collecting samples in Tecolote Canyon. This time around we collected water samples from various locations around the canyon specifically North Clairemont, Snead Ave., Mt. Edna, Linda Vista, and Transformer Stations. During the first day of lab, we over-filled the BOD bottles with the specified water samples and let them sit for approximately five days. The initial and final O₂ concentration (ppm) were measured with a dissolved oxygen meter in order to calculate the difference, which yielded the BOD concentration present in water samples around Tecolote Canyon. BOD stands for biochemical oxygen demand, which is the amount of dissolved oxygen needed for biological organisms in a specified body of water to break down organics and survive. The results in lab further explored the possibility of "dead zones" in Mission Bay. 

Cycle of "Dead Zones"

     

     “Dead zones” are often areas of water that contain little to no dissolved oxygen to the point where other marine life cannot survive and die or leave the habitat. The main concern with “dead zones” is that they can be man-created with nutrient pollution. Oftentimes, excess nutrients end up in oceans and rivers through waste and consequently, produce more algae within the waters that consume a great amount of oxygen that leaves less for marine life. 

From our lab data, the Tecolote sampling location with the highest initial O₂ concentration were LV#1 and NC#2 at 11.72ppm and 12.7ppm respectively.  Their final O₂ concentration was significantly smaller,but it did not affect the BOD difference (which still remained small in comparison). ME #2 and PS TT2 water samples had the highest BOD difference in concentration at 5.72ppm and 7 ppm respectively. These zones are potential “dead zones”, but considering the location of Mt.Edna #2 (higher up the canyon) the high BOD difference is mainly due to the run off of nutrients or present organics in the waste. As for the PS TT2 location, the “dead zone” is mostly likely due to run-off. One of the dangers of these possible “dead zones” is that they can continue to spread it nutrients across other water samples in the canyon and eventually end up polluting Mission Bay, which is the closest to the PS TT2 location. If these happens, fishes and marine life will no longer survive or exist in the Bay. Therefore, we should try retesting these areas of water in the future and hopefully see a decrease in BOD concentration for the sake of the Bay. 

Water Sample Sites in Tecolote Canyon with High BOD difference