Methylmercury Toxicity

Did you know the EPA has been warning pregnant women about fish consumption? Or that methyl mercury accumulates in your hair -- giving analysts a simple way to get a sample to test? A Chemical & Engineering News article summarizing mercury toxicity was published in early 2004: go to http://pubs.acs.org/email/cen/html/033007161508.html to read more. One last factoid: the Dartmouth College professor who died after exposure to a drop of methylmercury had no symptoms for 5 months after the exposure.

MInimata Disease

I was disappointed in the lack of material presented about the mercury poisoning in Minamata, Japan during the 1950s. The authors of the textbook even claim, "the poisonings at Minamata must surely rank as one of the major environmental disasters of modern times", but don't quantify the disaster. According to Japan's Ministry of the Environment, "2,265 individuals in Minamata and the surrounding area have been inflicted with mercury poisoning from the discharge of industrial waste water and 10,000 individuals are being compensated for their exposure and loses". Not to mention, the Japanese government and the Chisso corporation responsible for the mercury industrial waste have paid billions of yen to dredge the sediment containing the mercury and also to develop education programs about mercury poisoning. The picture really shows the horrible crippling that the body undergoes when exposed to toxic levels of methylmercury.

Oh no, no mo Rice!

I was struck in Chapter 8 when I read that there was an increased incidence of pulmonary adenocarcinoma (lung cancer) in Chinese women due to prolonged exposure to cooking-oil fumes. There have been numerous documented stories and research which has affirmed the presence and contribution of Polynuclear Aromatic Hydrocarbons (PAH's) to this phenomenon. This really hit home for me not only because of my love on chinese food and general concern for those who prepare it, but also my love of cooking. Have I been over exposing myself to high levels of PAH's in cooking oils and products all in search of that one delightful recipe? According to published work, the answer is yes. Although the names of the brands of synthetic oil were not revealed in these studies, the respirable cooking oil particulate is quite dangerous and prevalent. Ways to prevent high exposure are to take such cautionary measures such as working in well ventalated areas and to always cook with the blowfan on. Also whenever possbi;e try to avoid high oil temperatures because this serves to increase the amount of oil PM. For more, read this; http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8161241&dopt=Abstract.

Plant Buddies

Rachel Carson mentioned a case study in Holland, in which city workers planted marigolds in rose beds to successfully diminish nematode destruction. As a young girl, I remember visiting my grandparents' vast garden, which was surrounded by marigolds. Until just a few minutes ago, I had no idea that they planted them there for the safety of their flowers and vegetables. Marigolds, like many herbs, have strong odors that keep rabbits away and also aphids, little bugs that feed on vegetation. Not to mention, they do the job of an herbicide without the danger of using chemicals and introducing foreign species into an area. In an article from Flower & Garden Magazine, many other 'plant buddies' are mentioned and I think that you should take a quick glance.

San Diego's Greenhouse Gas (GHG) Footprint Group #1

The mayor of San Diego county set a goal to reduce the GHG emissions by 7% below the recorded levels in 1990 by the year 2012. Unfortunately, the emissions increased from 32.10 billion kg in 1990 to 39.7 billion kg in 2005. In order to get to the anticipated goal GHG emission need to be reduced by 30% or 12.40 billion kg. These numbers listed above are from the class being separated into various groups to collect data about CO2 emissions from various state, county, and city agencies. The amounts of CO2 collected were converted into kilograms and analyzed. Then the class was split into two groups with each having a different area of focus. The focus of group #1 were CO2 emissions from transportation which included fuel, mileage, and fleet based emissions.

The highest CO2 fuel based emissions came from car fuels including gasoline and diesel. In contrast the lowest fuel based emissions came from aviation and jet fuels. In order for the 12.40 billion kg reduction to happen, it was split into six two billion kg wedges. Solutions for reducing the wedges were created and are as follows:

1. Reduce the driving week by encouraging people to drive only six days per week instead of seven.
2. Encourage the automotive manufacturers to increase or have government mandated miles per gallon ratings to improve the miles per gallon a vehicle gets.
3. Replace natural gas with renewable energy such as solar or wind power.
4. Encourage people to join a carpool.
5. Give incentives for people to own hybrid vehicles by giving tax cuts to encourage people to replace their old cars with hybrid models.
6. Give incentives and more protection on the road to encourage people to buy and drive motorcycles instead of cars.

According to an article from the Union Tribune, the goal of reducing GHG emissions to 7% below the 1990 levels maybe impossible. Two solutions mentioned would require more than half of the vehicles be removed from the road or eliminating all residential and industrial energy use in the city. Of course these solutions are unrealistic but unless something drastic is done to reduce the GHG emissions, the emissions will continue to increase with the growing population of San Diego. From studies, the reasons for the increase in emissions from 1990 to 2004 were due to an increase in computer rooms that must remain cool, energy use from residential homes, and vehicles on the roads. Many of the people are optimistic because city residents might not be willing to make significant changes to their daily lives to lower the GHG emission. In order for emission reduction to happen education of the public has to happen to make people aware of the severity of global warming and the city needs to make incentives for people to want to change their daily lives to better the environment.

Artificial Trees: A Good Solution?

Jumping back into our Monday discussion about greenhouse gases, I mentioned a website I had found that talked about artificial trees. I actually went back and found the website that was talking about these "trees" and the article did sound convincing to me. Although the name trees might be deceiving, these devices look more like windmills than actual trees. Apparently, these "trees" individually can remove 90,000 tons of CO2 per year, which is equivalent to emissions of CO2 by15,000 cars. That sounds pretty amazing to me, considering the largest contributor to CO2 emissions are cars themselves. I do want to mention that these "trees" aren't perfect, they do take energy to collect the CO2, but it would create a renewable source of CO2 for synthetic gasoline.

San Diego's Greenhouse Gas Footprint Group #2

Have you ever considered how your city and even you could reduce carbon dioxide emissions? In San Diego, Mayor Sanders has advocated reducing carbon dioxide emissions in San Diego County to 15 % below 1990 levels by 2012. After some investigation, it was found that San Diego County’s Greenhouse Gas Footprint, the amount of carbon dioxide released into the atmosphere via various sources, for 1990 was 3.16 E10 kg of carbon dioxide and 3.87 E10 kg in 2005. Since San Diego has managed to increase their emissions in the last 15 years, the reduction needed to reach 1990 levels is 30 %. Taking into account electricity, natural gas, and industrial emissions reports from the SDG&E it was concluded that the problem needed to be solved with 6 solution wedges, each representing a 2 billion kg decrease in carbon dioxide emissions. The 6 solution wedges included the following:

Widespread electrical conservation included turning off computers when not in use and unplugging appliances in the home while not in use. Many suggestions were included in the transportation wedge including biking, walking, raising gas prices, and adding incentives for carpools. Also purchasing cleaner 4 stroke marine engines would limit carbon dioxide emissions from transportation vehicles. Environmentally economical zoning and building purposes high density housing and living close to work as options for lowing carbon dioxide emissions. Two other suggestions focused on increasing laws and knowledge about carbon dioxide emissions. For example, people in San Diego should purchase locally grown food instead of allowing massive transport from far away places. Not to mention, they should recycle and conserve and educate others to do so.

In an article entitled, “Alter climate? Change Ways”, authors sadly claim that Mayor Sanders’ goal will not be reached because people are unable to change their lifestyles to accommodate carbon dioxide emission reductions unless national laws were in place. However, I believe that if we educate the citizens, which the city claims to be attempting, that anything is possible. Not to mention, national laws take many years to establish and enforce, but each individual doing some of the suggestions above could be done tomorrow without significant sacrifices except maybe high density housing. Therefore, I suggest that we continue to educate individuals about global warming and give suggestions that people can do themselves for relatively cheap to help in decreasing greenhouse gas emissions.

Trace chemicals and reproductive health

Yesterday's Chemical & Engineering News has a great article about how environmental contaminants are causing infertility, declining sperm counts, miscarriages, and birth defects. This serves as a great introduction into our class topic! Give it a read and please comment.

Red Cross Symbol on Pesticide Products

Browsing through many different pesticide websites, I stumbled across one created by the National Coalition Against the Misuse of Pesticides (NCAMP). Their top story of the day reveled that the EPA gave manufacturer's of pesticides permission to place the Red Cross symbol on their products, in an exchange that the Red Cross receives part of the pesticide profit. The NCAMP group was furious with this decision, claiming that the EPA "violated the federal pesticide law and will mislead consumers into thinking that pesticides are not harmful". After viewing the Red Cross symbol applied to a Clorox container, I realized why some might be upset. It really does create a sense of false advertising. The cross is relatively large compared to the sentence describing the fundraiser aspect. People who cannot read, but recognize the Red Cross symbol as 'safe' might potentially be put in harms way. Especially, young children. Also, I believe that we should not have to resort to false advertising tactics that potentially could harm others in an attempt to make money for a agency dedicated to helping others! However, I also realize that this article was directly written by NCAMP and might be heavily influenced and filled with ideas that support their view.

Be Good to the Planet or Be Good to Yourself?

This week Time Magazine wrote a fabulous article on how the whole "Organic Craze" might not be the best thing for our environment. I may admit, I am one of those who eats organic foods as much as possible so as not to pollute my body and also to avoid all the complications that may arise when the pesticides reach the environment and water supplies. Never once did I think that my obsession with buying organic fruits and vegetables might actually not be the wisest decision.

It couldn't have been better timing for a greenhouse gas article to close up chapter 6 while also incorporating chapter 7 on pesticides. Since organic produce isn't always local, most likely it had to be flown in from across the country or even equator, thus contributing to the addition of greenhouse gases to our atmosphere. Pretty much the act balances itself out. The articles main focus was to buy local. Even if the produce isn't organic, it hasn't been boxed up an shipped all around the world, just so someone can have an organic pineapple.

Time reporter Gussow's famous statistic is that "Shipping a strawberry from California to New York requires 435 calories of fossil fuel but provides the eater with only 5 calories of nutrition."

It makes you wonder if that strawberry is really worth it.

Biomagnification of DDT

After reading about and discussing DDT in class the effects DDT had on eggshells of birds, I did some research and found this link which gives information about different insecticides. If you scroll down to the biomagnification section, within a table is a list of bird species and the amount their eggshell thickness was reduced because of DDT and DDE. I was surprised to see the amount of reduction that occurred in just these select species. I tried to find data about the reduction in eggshell thickness for the pelican and bald eagle but was not successful on finding recent or reliable sources. But, I was able to find a scientific article from 1999 printed in the International Journal of Epidemiology that studied the effects and trends of DDT in human breast milk for five decades from areas around the world. The trends show a steady decrease from the 1950s to the 1990s with the mean DDT levels being significantly decreased over the years. Latin America countries had the highest DDT concentrations in the breast milk which I think could be due to lack of regulation and extended use after other countries banned its use. It would be interesting to see if these trends still hold true in 2007 or if there has been a greater increase in DDT accumulation.

A number of the chemicals that make our modern daily lives possible also heavily influence the environment in which we live. When some of these chemicals are released into the atmosphere as vapors, they can interact with complex natural cycles to have unforeseen consequences. One of these interactions leads us to a group commonly called the greenhouse gases. Greenhouse gases (GHG’s) are gases either natural or anthropogenic in source that have the ability to absorb and re-emit light of the infrared wavelength. The interesting part is that this infrared light would normally escape into space were it not for the absorption events of the GHG’s. If enough of this thermal energy is captured and re-emitted back down to the planets surface a rise in global temperatures will result. The phenomenon that these gases produce is called global warming. This effect is akin to how the glass panes of a greenhouse allow light of visible wavelength pass through but trap the infrared light inside, thereby eventually raising the temperature of the greenhouse.
We attempted to measure the global warming potential (GWP, a relative measure of how effective a particular gas is at trapping infrared light, with carbon dioxide having a GWP of 1) of several laboratory solvents and gases, including CH4, CHCl3, CCl4, CH2CL2, CO2, and a halon mixture. Analyzing trends across these different gases would hopefully allow us estimate the impact of these gases on global warming at the rates they are currently being released as well as to make predictions as to the GWP’s of related gases.
(Fig1: Static Dilution Setup, Seen from the side)


(Fig2: Flowing Dilution Close-up)




In order to accomplish this, we took dilutions of these gases and measured them using Fourier Transformed Infrared Spectroscopy (FTIR). Whenever a gas must first have been vaporized from a liquid, a static dilution system was used to allow us to obtain quantitative dilution. We used a much more simple flowing dilution system whenever a gaseous source was available for us to make our dilutions from. The absorbancies were then collected and measured using a salt crystal FTIR collection cell. At this point the treatment of the data became highly mathematical. The wavelengths and intensities at which each molecule would absorb infrared radiation were entered into an equation that would give us out the GWP of that particular gas.
When we compared the GWP’s that we experimentally derived to “standard” values that have been tabulated already, we found that our results were vastly (about 10x-20x) lower that the published values. A quick glance at fig. 3 shows this. If we had gotten experimentally reasonable data, the bar graphs for each particular gas would match or at least be reasonably close. One likely culprit was the dubious security of air locks on the FTIR cells. If these locks were in fact leaky, then we were measuring gas concentrations that were significantly lower than what we were expecting to measure. Placing the larger concentration into the equations instead of the correct but unknown smaller concentration caused by the leaky cell would have given us this deviation. Other possible causes were incorrect use/calibration of the FTIR specs or human mistakes that took place in the dilutions.



Even though most of our data points were less than accurate, we were still able to make connections between some of the chemicals we use on a daily basis in the lab and the global warming effects we see increasingly each year. At the very least we were able to see that in fact, yes, greenhouse gases do absorb thermal radiation as well as the fact fact that some gases are more efficient in this action than others. Since these gases only represent a very small portion (excluding methane) of the GHG’s, we in fact only studied a small portion of the global warming effect. More research is needed into the entire field is needed not so much to discover more of the chemistry involved but more so into effective education techniques, for each day an individual does not fully understand his or her impact on the environment, the closer we get to changing our planet in a way we can’t fix.

Greenhouse warming potentials

Did you know that 40% of the worlds CO2 pollution comes from power plants? And another 20% comes from the use of cars? Who knew that using our lights in our homes could cause us so much harm. It is unfortunate that the use of electricity and vehicles have become very important in our everyday lives because they are the two biggest contributers to Global warming. Global warming is the warming of the earth’s climate and is estimated to cause severe climate changes in the coming decades. There are many gases that contribute to global warming, but some of the most important include: water vapor, methane, and nitrous oxide, and CO2. Today, we know the causes of Global warming but not much more is known about its future impact because we have yet to see any damages. Furthermore, the only thing that can be done is to predict what may happen and figure out how to stop it. In this lab, several common green house gases were tested to calculate their global warming potentials (GWP). Calculations of GWP are a great way to predict the impact a certain green house gas will have on the green house effect. The gases tested were CH4, CCl4 CH2Cl2, CHCl3, and Freon TF. They were diluted and measured by the Fourier transform infrared spectroscopy (FTIR ) machine. That information was then put into a spreadsheet that calculated the GWP’s for the gases.
the results are as follows
Gases Experimental Actual
Methane, Group1 1.349 23
Methane, Group2 2.798 23
Chloroform 0.0459 5
Freon TF 1.589 1
CH2Cl2 0.590232 9
CCl4 3.770566 1400
Carbon Dioxide 1
From the data collected it is obvious that the gases yielded very low values for the GWP of the gases. Despite that, the values did reflect the general trend of actual GWP values relative to each other with the highest being CCl4 having a value of 3.8 followed by methane with an average of 2.1 and chloroform being the least at 0.05. The halon mixture did not follow the GWP trend but had the lowest percent error.
In conclusion, we may not have found all the answers to global warming but from this lab we were able to predict what gases are contributing more to the greenhouse effect.

Hydrogen Fuel Concept Cars

Obviously on of the biggest hindrances in Hydrogen being incorporated into passenger vehicles is in its storage. Whether a metal hydride is used or pure liquid hydrogen, every phase presents its own problems. This is why large car manufactures such as GM, and individual brands like BMW have been working on safe, compact storage designs for the hydrogen energy. The concept cars they have drawn up either contain a tank for the hydrogen fuel within the car, or it is fully integrated into the chassis of the car. It is important to realize that when solving problems such as future fuels that although the chemistry of the process is extremely important, that the practical engineering and integration of the ideas cane be just as difficult to tackle. For more, read this issue of Popular Mechanics at http://www.popularmechanics.com/automotive/new_cars/1266796.html.

Solar Energy in La Mesa

After reading chapter six of our textbook, I recalled hearing in the news that La Mesa, California (in San Diego County) recently began employing solar energy at a water treatment plant. The solar energy harvested from the solar panel's will constitute 20% of the plant's power needs and reduce carbon dioxide emissions "equal to 219 cars traveling 12, 500 miles annually". Currently, "San Diego produces 18 megawatts of renewable energy a year using solar energy, methane gas and water". According to the news, Mayor Sanders plans to have more businesses in San Diego begin to use renewable energy in an effort to reduce carbon dioxide emissions and greenhouse gases. To follow up on these quotes and read about the installation costs, which is highly expensive, visit MercuryNews.