Welcome to our _OOL, Notice there is no "P" in it. We'd like to keep it that way.

Most people have claimed to do it at some point in their life. Some people even think it’s acceptable to do, but did you know that peeing in pools causes a set of unidentified reactions that releases toxic chemicals into the air and water?

Cyanogen chloride (CNCl) and trichloramine (NCl₃) are nitrogen containing disinfection byproducts (N-DBPs) in found in most chlorinated swimming pools. Both of these compounds are toxic to the human body. NCl₃ is associated with acute lung injuries and CNCl has been shown to affect the lungs, heart, and central nervous system when it is inhaled. The N-DBPs found in chlorinated pools are mainly attributed to chlorination of human body fluids of sweat and urine.

Source: jezebel.com

A recent study done at Purdue University studied the impacts of uric acid on CNCl an NCl₃ concentrations. They stated that close to 90% of uric acid found in pools comes from urination, if the only source of uric acid is urine and sweat. The study didn’t use actual body fluids, but instead made a body fluid analog to react with free chlorine of varying concentrations. They also collected pool water to see how uric acid reacts in these solutions. One of the key findings of their study is that uric acid is an “efficient precursor” of these toxic compounds and that it is also a strong function of chlorine/precursor ratio, pH, and temperature. Overall, the research article concluded that decreasing the urination in pools, which is mostly a voluntary action, would improve air and water quality without having to change any other factors.

The article from the Latin Post did a pretty good job in summarizing the study. It reported on most of the aspects that were in the study. It mentions that how most uric acid comes from urination and what the two toxic compounds that come from uric acid are. They author also gives a good amount of background to the implications of the article, discussing the related health impacts of CNCl and NCl₃. Most of the information in this article though is almost word for word from the news release about the study published by Purdue University. The parts that aren’t word for word have only a couple of words changed. Also, the only link in the news article is to the news release by Purdue, not the actual research study. Overall, the article did a good job summarizing the findings of the study but did so by essentially copying another news release.

Study (from MLibrary): http://pubs.acs.org.proxy.lib.umich.edu/doi/pdf/10.1021/es405402r

News article from Latin Post: http://www.latinpost.com/articles/9931/20140401/study-urinating-in-pools-produces-harmful-toxins.htm

News release by Purdue University: http://www.purdue.edu/newsroom/releases/2014/Q2/swimming-pool-urine-combines-with-chlorine-to-pose-health-risks.html

Mercury Pollution and the Artic Meltdown

As we’ve talked about in class, Arctic sea ice continually shifts from perennial to seasonal ice and is associated with the opening and closing sea-ice leads. Sea-ice leads are large transient channels of open water in the ice. These affect atmospheric and biogeochemical cycles in the Arctic.  Mercury and ozone are rapidly removed from the atmospheric boundary layer during the depletion events in the Arctic. As we’ve talked about in class, this is caused by destruction of ozone but along with this, oxidation of gaseous elemental mercury in the atmosphere occurs and subsequent deposition to snow and ice happens.

These ozone depletion events can change the oxidative capacity of the air by affecting atmospheric hydroxyl radical chemistry, whereas atmospheric mercury depletion events can increase the deposition of mercury to the Arctic, some of which can enter ecosystems through snowing and snowmelt. This convective forcing provides additional Hg (0) to the surface layer at a time of active depletion chemistry.

The original research paper presented these models to illustrate. Yellow boxes are periods when air masses crossed upwind areas of consolidated sea ice. Black boxes are periods when air-mass trajectories crossed open leads. The satellite images represent four typical sea-ice conditions that occurred during measurements

I thought this article was excellent. They explained the topic clearly while presenting context into the conversation of mercury deposit and the arctic meltdown. This article doesn’t seem to present a significant sort of bias and presents other experts’ opinions on the topic.  I thought it was interesting how the writer of the article presented information about the re-emission of mercury into the atmosphere; thus, pushing the idea that this research isn't conclusive and that this article is mostly for exposure on the topic.

While the article was short, it gave a great overview of the topic. It clearly explained that these are “preliminary” findings and that further research is necessary to make complete conclusions. I personally thought this is one of the better papers I’ve read and it gave clearer picture of the original research than the original paper did.

I give it an 8.5/10. While I didn’t think the models were necessary to understanding the paper, the piece doesn’t give any link to the original research and I had to take a significant amount of time looking for it. Ok, it wasn’t that hard. Also, Joel Blum from UM is quoted here! That's cool.  With bonus points included for UM reference,  I'll give it a 11/10. 

Note: You might need to use MLibrary to get the piece.

Article
http://www.scientificamerican.com/article/toxic-mercury-pollution-may-rise-with-arctic-meltdown/

Original Publication
http://www.nature.com.proxy.lib.umich.edu/nature/journal/v506/n7486/full/nature12924.html

Toxic Vegetables or Toxic News Articles?

As we've learned in class, heavy metal contamination in soil can lead to harmful health effects. Lead (Pb) is a heavy metal that is commonly found in soil within urban regions as a result of human activities including fuel combustion and past usage of leaded paints. With an increasing interest in urban agriculture and city farming projects, this can present a cause for concern for city health and parks departments.

A recent news article titled, Root of all evil: Vegetables in NYC gardens are 'toxic', published by the New York Post brings attention to heavy metal contamination within urban farms. The article describes how citizens who get there produce from New York City urban gardens are at high risk of exposure to unsafe levels of Lead in carrots and other root vegetables. The article also mentions how no threshold containment level for lead is currently set for vegetables in the United States, comparing observed lead levels to the European Union's threshold. Furthermore, the levels of lead found in various herbs including basil and thyme were noted as being "off the charts"!


(Image credit: NYPost.com)

Generating the "toxic buzz" expressed by this article is a recent study published in Environmental Pollution by researchers at Cornell University's Department of Crop and Soil Sciences. The study analyzed levels of Lead, Barium (Ba), and Cadmium (Cd) in garden soil and vegetables around urban areas of New York State. The objectives of the study were to determine if soil contaminant levels could be linked to vegetable levels, compare metal concentrations in urban garden produce to market-bought produce, and to determine if a significant health hazard exists at the contaminant levels observed. Samples of fruit, leafy vegetables, root vegetables, and herbs were gathered from farms in New York City and Buffalo. Because the U.S. does not have health-based standards for metals in garden food, the study used European food guidance standards. Overall, soil and vegetable levels did not correlate (i.e. high variability between vegetable and soil contaminant levels), and although Pb levels in urban produce was higher than market-basket produce, the researchers concluded that the data are not significant enough to represent a health hazard. 




(Pb concentrations in garden-grown vegetables by crop type (mg kg⁻¹ d.w.). Boxes represent 25th, 50th and 75th percentiles. Whiskers extend to 5th and 95th percentiles. Image credit: McBride et. al)

The New York Post article paints a very different image of the results presented by the journal study. Although the levels of Pb were highest in root vegetables and herbs were highest, the news article makes no mention of the high variability, confounding factors and level of error presented by the study. Factors that affected the variability included soil pHs, organic matter, and aerosol lead deposition dependent on each garden's location. The study also mentions that rudimentary analytic tools may have contributed to the high level of error in some of the measurements. The news article further inflates the subject with its use of exaggerated language; quoting a pharmacologist claiming, "your playing Russian roulette with this," and including urgent calls to action by local politicians purporting the "serious health risk" presented by the data displays an irresponsible and inaccurate reporting style by the New York Post.

I enjoyed reading into the issue of heavy metal contamination within urban farming systems. This article brought attention to the issue and gives a decent summary of the the risks and health implications of lead exposure and the presence in community gardens. I think a valuable piece of information expressed by the article was that the exposure levels to contaminants in urban produce must be further addressed and studied.  However, the political and reporting biases presented in this NY Post article drastically overinflated the results of the study cited. I therefore would give this article a rating of 6/10.


New York Post article: http://nypost.com/2014/11/16/toxic-veggies-found-in-nycs-community-gardens/

Original research study: http://www.sciencedirect.com/science/article/pii/S0269749114003431

Plastic Microbeads are Contaminating the Great Lakes

Microplastic beads can be found in common household products such as facial washes and exfoliants and have been the subject of many recent scientific studies. These fine particles can be washed down the drain, pass through waste water treatment facilites and accumulate in water supplies such as the Great Lakes. It is hypothesized that these particles can have a negative impact on wildlife. And so, over the past few years, organizations such as the Great Lakes and St. Lawrence Cities Initiative have worked to regulate the use of these particles.

A recent article published online in Vice News addresses the growing concern over the accumulation of plastic microbeads in the Great Lakes. This article explains current efforts to regulate these particles by state and local governments. The Vice article also explains how the pollution of these microbeads will harm the Great Lakes environment and its wildlife surroundings.

In order to explain the levels of plastics in the Great Lakes, the article cites a study by scientists at the State University of New York – Fredonia and the 5 Gyres Institute in California. This study documents the levels of microplastics in the surface water of the Great Lakes. Samples were taken by trawling Lake Superior, Lake Huron and Lake Erie. overall, 21 data points were taken.  

The Vice article does a good job of citing the study to explain that there are these substances in the lakes, and that they can come from household products. Unfortunately though, this is the only part of the article that is backed up by cited scientific research.

The article makes several claims about the impact of these microbeads, and although they might make sense, and may be factually accurate, the article does not cite any science to support these claims. One argument is that once these microbeads enter the waterways, they begin to absorb pollutants and carry them to the lakes. It is also asserted that, because these beads can be the size of fish eggs, they may enter the food chain and cause harm to wildlife through biomagnification. Neither of these claims are cited with peer reviewed scientific evidence and so I am hesitant to accept them as fact. 

All in all, the Vice article does a good job of explaining the issue of microbeads in the Great Lakes. They accurately explain the study that was done and make factual claims about the products that contain microplastics. Unfortunately, while seemingly attempting to increase the importance of this issue, the authors make claims that are not explained through peer reviewed scientific articles. Because of this, I would give this article a 6/10.

Link to Vice News Article

Link to Marine Pollution Study

Link to Marine Pollution Study (With MGet It)

Researchers calculate “hidden” emissions in traded meat

Although previous studies have quantified carbon dioxide emissions embodied in products traded internationally, there has been limited attention to other greenhouse gases such as methane (CH4) and nitrous oxide (N2O).

Recently, an international team of researchers has estimated the amount of methane and nitrous oxide that countries release into the atmosphere when producing meat from livestock, and assigned the emissions to the countries where the meat is ultimately consumed. They found that embodied, or "hidden," emissions in beef, chicken and pork have increased by 19% over the past 20 years, and that there is currently a global instability caused by a large number of countries contributing to the production of emissions in another country.

Global emissions of CH4 and N2O account for approximately 27.7% of total radiative forcing since the pre-industrial era, and, in 2001, livestock accounted for 25% of this. Thus, direct emissions of CH4 and N2O from livestock worldwide represent approximately 9% of total anthropogenic greenhouse gas emissions.

In their study, the researchers, from the Carnegie Institution for Science, the University of Siena and University of California (Irvine), analyzed data from 237 countries and found that between 1990 and 2010, 36.1 Mt of CO2-equivalent (CO2-eq) emissions were related to meat produced in one country and consumed in a different country.

Trends of global non-CO2 emissions (Mtons of CO2-eq)

embodied in traded beef (A), pork (B) and chicken (C) (right axis,

red) compared with total beef, pork and chicken emissions (left axis,

blue) during the period 1990–2010.

The largest amount of embodied emissions was from beef (26.7 Mt of CO2-eq), pork (7.3 Mt of CO2-eq) and chicken (2.1 Mt of CO2-eq) respectively.

In Europe, meat exported from France to Italy and Greece embodied 1.4 Mt and 1.2 Mt of CO2-eq emissions respectively, and Italian imports of meat from Poland, Germany and Netherlands embodied 0.7, 0.6, and 0.7 Mt of CO2-eq emissions, respectively.

To sum up, I think science daily did a good job in introducing and summarizing a research result. Actually, this article is ‘based on’ materials provided by Institute of Physics (IOP). Which means sciencedaily just totally referenced a short summary from IOP and added a short summary.  But since sciencedaily article successfully attracted readers to pay attention to a significant environmental issue and referenced its original source properly, I still consider this article a good and clear science article that is suitable for public media.

Sciencedaily article:http://www.sciencedaily.com/releases/2014/11/141113195152.htm

POI news:http://www.iop.org/news/14/nov/page_64443.html

Original Paper:http://iopscience.iop.org/1748-9326/9/11/114005/

Marine Plastic Pollution: The Threat Pervading Australia’s Waters

Water availability and ecosystem environments have become of increasing concern as more and more contaminants are leaching into natural waterways. A study conducted by the University of Western Australia and CSIRO sought to determine the composition and pathways of some of the most harmful physical contaminants: plastics.

The team characterized and estimated concentrations of marine plastics around Australia using a new-towing method, which would allow inference for potential pathways of plastic pollution. They used three consecutive 15-minute net tows at 57 different locations around Australia, and chose a random sample of 200 collected pieces for polymer composition analysis. Of these 200 pieces, 67.5% were made of polyethylene, 31% from polypropylene, 1% from expanded polystyrene and 0.5% ethylene vinyl acetate.  There was also shown to be an inverse relationship between concentration of these contaminants and wind forcing, where higher plastic concentrations were observed in areas with lower winds. 

Julia Reisser and her team found that a majority of the plastic pieces sampled had low circularity in their shape as compared to manufactured products, lending to the idea that they’re the result of degradation from larger plastics. Micro-plastics, they found, were the most common type of debris, and most commonly came from hard plastics. These plastics most commonly accumulate at the surface, but lose buoyancy over time due to biofilm buildup. This lower water permeation of small plastics opens up the discussion on toxic effects to marine life: it has been shown that these particulates adversely affect not only fish, but also large marine vertebrates such as baleen whales. Australia is a particularly interesting study location, as the plastics observed in the study can be moved fairly easily around the country. Both isolated and populated locations are at risk, as many different currents allow for plastics to readily flow: Antarctic Circumpolar current, South Equatorial current, East Australia current, West Australia current and a few other coastal current systems all move plastics to aggregation spots around the coast. Because of this breadth of sources, regulation of waste from plastic would be rather difficult to employ and enforce. The authors of the study suggest more “sea-studies on characterization, spatial distribution, and pathways of marine plastics in coastal and oceanic regions… as well as on marine plastic toxin loads and interactions…” to improve our knowledge of the pollution, and make more apparent the need for more stringent regulation.

Overall, I think the article from The Guardian fulfilled its goal: it brought attention to an important environmental pollution issue that needs to be dealt with. However, when presenting the findings of the study, they omitted almost all of the research and instead filled it with quotes from the primary author. While still informative, I believe it would have been more impactful to have taken some of the conclusions from the study to give weight to the severity of the subject.

The Guardian article:

http://www.theguardian.com/environment/2013/nov/28/marine-plastic-pollution-the-threat-pervading-australias-waters

PLOS ONE article:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0080466#authcontrib

POPs Detected In Loggerhead Sea Turtles

            Loggerhead sea turtles, (Caretta caretta) are large benthic consumers that have recently become of particular interest to scientists. Although loggerhead sea turtles have been on the U.S. Endangered Species Act for over thirty years, little information is known about the male species due to the rarity of it being encountered by humans. Unknown information includes migration patterns, exposure and risks of persistent organic pollutants (POPs), and prey choice. The primary exposure route of bioaccumulation contaminants in loggerhead turtles is through trophic transfer. Previous POPs detected in juvenile and female loggerhead turtles include: organchlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). In related studies, marine predators have also had elevated levels of toxaphenes and hexabromocyclododecanes (HBCDs). These contaminants have been known to cause cancer and negatively impact growth, development, and reproduction.

            The first study to test POPs in male loggerhead turtles’ blood plasma based on migration patterns was conducted by Ragland et al. in April of 2006 and 2007. The article is titled “Persistent organic pollutants in blood plasma of satellite-tracked adult male loggerhead sea turtles (Caretta caretta).” The 29 sea turtles were captured near Port Canaveral, Florida and blood samples were drawn from the back of the neck and analyzed using gas chromatography-mass spectrometry. Also, satellite transmitters were placed on the back of the shells of the turtles to track migration patterns for sixty days each sample year. The satellite tracking devices indicated that nine individuals were residents and remained near the capture site, whereas ten transients migrated northward near Pamlico Sound, North Carolina to as far as Cape May, New Jersey. Results of the blood plasma analysis indicated that OCPs and PBDEs were greater in transients that residents. The possible causes for this could be correlated to turtle size, increased industrialization, land use, higher human population, and a bigger watershed in the north compared to a smaller watershed in Florida. Lastly, the study found that total PCB levels were also slightly greater in transients than residents indicating different diets and foraging patterns.        

            Nicholas Bakalar, from The New York Times reported on these findings in his article titled “Migrating Sea Turtles Pick Up More Pollution.” Bakalar emphasizes that 67 different chemicals most likely originating from pesticides were found in the blood of the loggerhead sea turtles. Bakalar states, “It is possible that the fish and invertebrates that turtles feed on in northern waters are more polluted.” A possible cause for this is sea turtles that migrate far distances usually consume more food and are on average larger in size than residents. However, it is unclear to scientists how to define “good health” in loggerhead sea turtles, since they all seemed to be reproductively active based on testicular biopsies.            

My main issue with the original research article is 29 sea turtles were tracked yet only 19 were analyzed for POPs. Ragland et al. fails to mention why the other 10 individuals weren’t included in this study, was it due to lack of POP’s or migration patterns? Another issue I had with this research is Ragland et al. never mentioned whether or not they recaptured these 29 individuals to remove the satellite tracking devices from their shells. This alarms me because this could impact migration, reproduction, foraging, and their ability to prosper since they are already an endangered species.  However, I did like the fact that future studies were suggested to elaborate on this research since this was the first study of its kind.

Overall, I think Nicholas Bakalar from The New York Times accurately reported on the findings of the original research article by Ragland et al. The article is merely a summary of the findings; Bakalar does not add any opinions or ideas of his own to this topic. However, I think he does a good job of getting the message across that man-made pollution is putting loggerhead sea turtles at risk. I would give The New York Times article a 9/10 because I see no problems with the accuracy of this brief article, but I would have liked an outside perspective on the subject matter.

Original Research Article:

Ragland, J. M., Arendt, M. D., Kucklick, J. R. and Keller, J. M. (2011), Persistent organic pollutants in blood plasma of satellite-tracked adult male loggerhead sea turtles (Caretta caretta). Environmental Toxicology and Chemistry, 30: 1549–1556.

http://onlinelibrary.wiley.com/doi/10.1002/etc.540/full

Media Article:

Bakalar, Nicholas. (2011), Migrating Sea Turtles Pick Up More Pollution. The New York Times.
http://www.nytimes.com/2011/04/26/science/26obturtles.html

Birth Control Causing Decline in Fish Populations

One of the major sources of water pollution is from human waste water. In addition to fecal matter, cosmetic products and cleaning supplies, pharmaceuticals pass into waste water through urine. Though many chemicals are metabolized to inactive forms before excretion, some chemicals in urine pose a threat to marine life. One such chemical is 17α-ethynyloestradiol (EE2), a synthetic estrogen found in birth control. High levels of EE2 in local waters can have negative direct and indirect effects on the environment. Response to EE2 varies considerably between species, with fish having much higher sensitivities than invertebrates. In fish, EE2 causes abnormal reproductive behavior, reduced gonad size, and feminized males. These major sexual changes negatively affect populations.

A recent study in the journal Philosophical Transactions of the Royal Society B examined the direct and indirect effect of EE2 on the ecosystem. The study was a long-term, whole-lake experiment that used a before-after-control impact design. With this setup, the researchers could study a natural environment and monitor multiple species and interactions. Significant direct effects of EE2 included a near extinction of fathead minnows, and a decline in body condition of male lake trout and both male and female white sucker. Indirect effects of EE2 included increases in zooplankton and emerging insect populations, most likely due to a decline in small-fish populations that would feed on them. Additionally, the study found a 23 - 42% decline in lake trout biomass, most likely from a loss of prey species. The image below summarizes the findings. These finding are important because they examine previously unresearched effects of EE2 on the environment. Though the possibility of species extinction is clearly a concern, other issues could arise from high EE2 levels in water. One potential impact could be increased spread of malaria. If EE2 decreases small fish populations near warmer cities, then the mosquito levels could dramatically increase. Mosquito-borne diseases would also likely increase.

Solid arrows represent direct effects, hatched arrows represent likely indirect effects and white arrows represent potential direct effects. The relative magnitudes of the responses are indicated by percentage changes in abundance or biomass.

I stumbled across this article while searching "water pollution study" on Google News. The article is titled "Contraceptive chemicals in the water supply nearly made the minnow extinct: Study" and it is from the website LifeSiteNews. According to the website's About page, they are a "non-profit Internet service dedicated to issues of culture, life, and family." The website was founded by a Canadian national pro-life organization but they "are not involved in direct political action and do not support or oppose political candidates or parties." LifeSiteNews.com claims to be "strictly a news and information service." With that background out of the way, this article had an interesting take on the study. I was surprised by just how well the article summarized the study. They presented all of the findings and didn't exaggerate or skew the data in their presentation. The only complaint I had was that they used the high range of the 23-42% biomass loss by reporting, "the lake trout numbers also declined by more than 40 percent." Except for that instance, the summary of the study results seemed very clear and accurate. The website made the content easy to understand while still relaying all important information. It was after the overview of the study when things began to get interesting. The article quickly shifted to politics by stating that women taking birth control should be taxed for causing pollution. The article quotes British economist Tim Worstall: "BP has to pay to clean up the waters of the Gulf after Macondo … women who take the contraceptive pill should pay £1,000 ($1,500) a year more in tax."

I thought that the study design, in particular, was very impressive. The fact that this study was conducted on a natural environment makes the findings directly applicable to real-world situations. Additionally, though the direct effects of EE2 are not revolutionary, the indirect effects present previously unconfirmed issues. I found the news article to be particularly interesting. Despite the political agenda of the website, the article did a fine job conveying the information from the study. It was only after all of the research details were presented that the article incorporated the findings into a political argument. I would rate the article 7.5 out of 10.

News Article: https://www.lifesitenews.com/news/contraceptive-chemicals-in-the-water-supply-nearly-made-the-minnow-extinct

Journal Article: http://rstb.royalsocietypublishing.org.proxy.lib.umich.edu/content/369/1656/20130578.full

Sediments harm clownfish larvae

Many aquatic species can be influenced by anthropogenic activities. Some may be familiar with the impact of rising CO₂ concentrations on ocean acidification and coral reefs. Dam construction and overfishing have also hurt certain aquatic species. As seen by these examples, the physical activity itself or the substances associated with these activities can cause the harm. Within these two categories, there may be a myriad of substances that can impact certain species. Therefore, an important area of research that can add to such knowledge of the harm human beings cause on those living in water can be the study of how specific substances associated with anthropogenic processes influence specific aquatic species.

                                          Clownfish.

                                          Credit: Erika Woolsey

 

An article on Science Daily entitled “Arrested development: Sediment wreaks havoc with fish larvae” discusses the findings of a publication by Wenger, et al. in The Journal of Experimental Biology regarding the impact sediments have on clownfish larvae. The Journal of Experimental Biology publication starts off by stating that research into clownfish larvae has been relatively new and gives a broad overview of factors relating to sediment deposition that may hurt the larvae, including increased water turbidity and the presence of the sediment itself. The publication then discusses its results, which included the observation that a general increase in larvae development time was associated with increased sediment concentrations. Interestingly, another key finding was that the increase in the weight and length of the larvae was particularly pronounced for larvae exposed to low sediment concentrations but not for those exposed to no or higher sediment concentrations. Finally, though differences in sediment concentration affected larvae development, the study notes that varying sediment concentrations alone did not affect the mortality of the fish significantly.     

The Science Daily article provided a simplified yet moderately inaccurate summary of The Journal of Experimental Biology publication. A key point that the Science Daily article brought up was that sediment does increase the time for clownfish larvae development, an idea the publication would agree with. The Science Daily article then goes on to make a case that this will negatively affect clownfish populations because increased time as larvae correlates with increased mortality from predation vulnerability. This idea may logically make sense and is not contrary to the publication’s finding that differing sediment concentration alone had almost no effect on mortality because the study did not expose the larvae to predators, which can reasonably kill the larvae more easily than adult fish. Though the Science Daily article does well in the above, the Science Daily article incorrectly states that the time it took for larvae to develop doubled in “many cases”. This is incorrect because information reported in The Journal of Experimental Biology publication mentions that only two larvae exposed to high sediment concentrations had a doubling of “pelagic larval duration”, or PLD. Furthermore, the publication finding that the median time to metamorphosis for larvae exposed to sediments was 12 days compared to 11 days for the controls does not support the “many cases” argument.    

In addition to mentioning false information, the Science Daily article also has three other flaws: making assumptions, using strong language inappropriately, and excluding key information in the publication. The Science Daily article assumes that sediment comes from “dredging and flood plumes” whereas The Journal of Experimental Biology publication just oftentimes describes sediments as “sediments” or “suspended sediments”. The Science Daily article also uses strong language in its title with words such as “wreaks havoc”. This language is certainly an exaggeration given The Journal of Experimental Biology publication’s finding that sediment concentrations alone have little influence on mortality. Finally, The Journal of Experimental Biology publication devotes considerable attention to the sediment’s implications on larvae length and weight, a topic the Science Daily article does not discuss.

Overall, the Science Daily article brings attention to the important issue that sediment can lead to increases in time for clownfish larvae development. However, the Science Daily article does so in a way with a multitude of flaws, including the providing inaccurate information, the making of assumptions, the use of strong language, and the exclusion of important information. This is why I would give the Science Daily article a score of 5/10.

 

Links:

Science Daily Article:

http://www.sciencedaily.com/releases/2014/10/141023101009.htm

The Journal of Experimental Biology Article: http://jeb.biologists.org/content/early/2013/12/03/jeb.094409.full.pdf+html

Decreased risk to humans with dropping pesticide levels in natural water sources

Pesticides, herbicides and fungicides enter our natural water systems from runoff from home and agricultural use.  Once these intoxicants enter our rivers and streams they pose a hazard not only to humans, but also to wildlife.  From 1992 to 2011 over half a billion pounds of herbicides, insecticides, and fungicides were used annually on crops and to protect from insect-borne disease (1). The U.S. Geological Survey ran a 20 year survey of rivers and streams to track changes in the prevalence of these contaminants and published a study with the findings in the journal Environmental Science & Technology, and an article in the New York Times discussed these findings.

The New York Times article Pesticide Levels in Waterways Have Dropped, Reducing the Risks to Humans highlights the findings of the article Pesticides in U.S. Streams and Rivers:  Occurrence and Trends during 1992-2011 published in the journal Environmental Science &Technology.  The study examined the prevalence of a large number of pesticides at 200 sites in rivers and streams over a period of 20 years, starting in 1992 and continuing to 2011 for the the presence of these compounds as well as if the concentrations exceeded the aquatic-life or human-health benchmarks.  The sites were located in a mix of different land use areas, including agricultural, urban, and mixed.  The scientists found that the proportions of steams that exceeded the aquatic-life benchmark for at least one pesticide were similar between the two decades for agricultural and mixed-land-use streams, but increased in urban streams.  While the aquatic-life benchmarks were exceeded at about the same rate from 1992-2001 and 2002-2011 the human-health benchmarks were only exceed in one agricultural stream during 2002-2011.

Figure 1. The national monitoring network for pesticides in streams and rivers included 182 sites during 1992-2001 and 125 sites during 2002-2011, with 96 of the sites comon to both decades.  Concentration trends were assessed for 39 major rivers with mixed land use and 27 urban streams.  From Pesticides in U.S. Streams and Rivers: Occurrence and Trends during 1992-2011

The study attributed this decrease to a decrease in use of these compounds due to voluntary discontinuation, as well substitutions by new compounds. The new compounds were to be stronger so they can be used in smaller amounts which decreases how much can runoff into rivers and streams.  The New York Times article includes a quote from one of the study's scientists which also attributes some of decreases to the success of regulatory changes "'It's very clear in the data that regulatory changes in use do affect what you see in the streams"' said Wes Stone, a hydrologist with the Geological Survey...".  

Figure 4. Proportion of streams with one or more pesticides that exceeded a chronic aquatic-life benchmark was very similar between 1992 and 2001 and 2002-2011 for agricultural and mixed-land-use streams, but much greater during 2002-2011 for urban streams.

The study also highlighted the fate of seven pesticides that were frequently found to exceed the aquatic-life benchmarks to highlight how changes in concentrations and usage of a compound can lead to many different trends. For most of these compounds they found decreasing concentrations, but one found at an increasing rate and concentration was Fipronil, the main ingredient in many cat and dog flea and tick prevention medications.  Fipronil usage in the United States began in the late 1990s as a replacement for organophosphate insecticides.  It was found in 70% of urban streams, and 20% of agricultural and mixed-land-use streams between 2002 and 2011.

While the 20 year study shows some decreases in amount of pesticide, herbicide and fungicide usage in rivers and streams, this study only monitored less than half of the number of these compounds used in agriculture in the U.S.  This limited study was due to both limitations in analytical methods for analysis as well as limitations in funding.  The scientists of this study have stated that the result of this limited scope of study is that the risks to wildlife are probably higher that the findings of this study show.

The NY Times article did a good job of describing the results of the U.S. Geological Survey study.  It highlighted the main findings of the study, and included some of the limitations.  I also liked that it included a quote from one of the researchers discussing the successes of regulatory work.  I thought that this was a strong message to the readers about a positive outcome of regulatory work for environmental and human health.  The NY Times article was a bit strong in a few of the statements it makes, for example "The results nevertheless documented a striking decline in danger to humans from pesticide pollution", when the Environmental Science and Technology article states that the proportion of streams with at least one pesticide that exceeded the aquatic-life benchmark were very similar between the two decades.  This bold statement by the New York Times article makes it appear that the number of pesticides in the water is less dangerous than it may actually be.  Despite some of the overly strong statements, I thought that it was a strong article and stayed true to the Environmental Sciences &Technology article, therefore I give it a 7 out of 10.

Journal Article:
(1) http://pubs.acs.org/doi/pdf/10.1021/es5025367

New York Times Article:
http://www.nytimes.com/2014/09/12/us/pesticide-levels-in-waterways-have-dropped-reducing-the-risks-to-humans.html?_r=0