Environmental Forensics - Reasons for Mass Death of Fish in Styx River - Case Study Example

Environmental Forensics Introduction A fish kill refers to any abrupt and unforeseen mass death of fish. Fish kills are mostly attributed to pollution or contamination of waters (O’Sullivan, 1995). In this case, a massive fish kill involving rainbow trout (Salmo gairdneri) took place in the Styx River approximately five miles outside the village of Styxton. Masses of dead fish and dying fish gasping were reported in different sites along the river. It was also reported that the river seemed darker than usual and also that the river had of dirty colored foam on the surface. This fish kill is similar to the one that occurred in Atlantic Menhaden (Brevoortia tyrannus) within the tidal part of Peconic River in 2015 where there was a mass fish kill (Tomarken et al, 2015). Along the river there is Styxton Sewage Plant, Riverside Brewery and ABChemicals that manufactures methyl-mercury and also these are possible sources of river contamination. The aim of this report is to find out the cause of the fish kill and recommend strategies to prevent further disasters. Possible Contaminants Methyl-mercury Heavy metals are common cause of water contamination. A good case is a pollution spill from Romaniaat entered the River Tisza in Hungary in 15th March 200. Water management officials said the spill, believed to contain heavy metals, had dyed the river black for at least 20 kilometers. In this case, the river seemed darker than usual just like in River Tisza where the river turned black and hence heavy metals such as mercury are possible contaminants. ABChemicals produces methyl-mercury which is a possible contaminant on water quality and aquatic life. Effects of methyl-mercury on aquatic life include death, decreased reproduction, impaired growth as well as abnormalities in behavior. Generally, fish gets methyl-mercury nearly entirely from dietary intake. After bioaccumulation of methyl-mercury in fish and other aquatic animals, acute toxic effects and death occur especially in adult fish. Evidence shows that the decreased reproduction potential as well as decreased survival occurs due to chronic toxic impact of dietary exposure of fish to methyl-mercury (Paerl et al, 1999). Mercury pollution is normally in the inorganic form, but aquatic organism and vegetation in rivers and lakes transforms the mercury into poisonous methyl-mercury. Fish feed on contaminated vegetation and the mercury gets biomagnified in them. Protein in fish binds more than 90 percent of the eaten methyl-mercury such that it is impossible to remove it and hence higher chances of toxicity Chlorine Chlorine is a possible contaminant because it is used in disinfecting treated sewage before the sewage returns to the river. Chlorine kills fish and hence it could be a possible cause of the fish kill since the chlorine kills fish just like it kills germs during disinfection. Liquid chemical OTO (othotolidine) can be used to test chlorine whereby when added in the water the color of the water turns yellow if there is chlorine (Lamotte Company, 2012). Raw Sewage Sewage consists of domestic and industrial wastes and is more than 99 percent water and the other percentage consists of ions, solid suspensions as well as harmful bacteria and other microorganisms. Sewage is a main carrier of diseases due to human wastes in this case from the village of Stxyton and toxins from industrial wastes and in this case the Riverside Brewery and AB Chemicals. This is collaborated in Guardian (2014) where in Glastonbury water quality was harmed and also fish were killed due to sewage leak in the river. Surfactants These are substances used in industries in cleaning and all and they act by lowering the surface tension of water. Surfactants in this case study could be originating from surfactants used in cleaning the sewage as well as in ABChemicals. The surfactants have toxic effects on aquatic organisms and hence they could be the possible cause of the fish kill (FAO, 2015). Ammonia Ammonia is a possible contaminant in this case. Ammonia pollution can originate from the sewage and well as industry effluent from the ABChemicals Company. Ammonia is in form of ammonia ion in water and readily diffuses across the tissue barriers of the fish and hence it is potentially toxic to the fish. Ammonia has specific toxic effects on the brain and this is the reason why there are nervous symptoms during ammonia toxicity to the fish. Ammonia has a particular toxic effect on the brain; this is why nervous symptoms during ammonia toxicity (FAO, 2015). An example of water contamination by ammonia from sewage occurred when human waste polluted nearby river White-lake. During Glastonbury festival, a steel tank that was used for storing sewage for people who attended the festival leaked into river White-lake which harmed the fish as well as water quality. The investigation found out that high levels of ammonia entered the water and this is what caused the harm. Sampling Step 1 Take water samples in the immediate area of the dead/dying fish Using two clean 1-litre bottles, sample water close to the shore but not the stagnant water but ensure that surface water is included Step 2 A few fish should be examined for external abnormalities like skin discoloration and distended, pale or darkened gills. Step 3 Discharges upstream of the kills should be located. Both sides of the river should be explored carefully and all inputs suspected to have polluting substances should sample. Samples should be taken upstream of any likely pollution source because this assists in detecting changes in quality of water. Water sample from the river will be collected at the beginning of the river because less oxygen occurs at the beginning of the river. Sediment samples from river. Sediments sample should be collected from the edges and the middle of the river because contaminants reduce as we get deeper in the river. Collection of organic samples for example DO, COD and oil grease should be done using glassware whereas plastic containers should be used to collect heavy metals and other parameters (TomarkenJ, 2016). Literature shows that it is important to soak the sampling containers in HNO3 for 24hours and clean them using laboratory detergent, rinse with tap water and lastly rinse using de-ionised water to ensure that there is no contamination of the containers (CCMP, 2001). Analysis Determination of Dissolved Oxygen using Winkler Titration This test is used to measure the concentration of dissolved oxygen in water samples. In this method, iodide (I−) is added to a water sample. Oxygen dissolved in the water oxidizes the iodide ion (I-) to iodine. The amount of iodine that is formed is determined by titrating using a standard thiosulfate (S2O3 -2) solution. The amount of the dissolved oxygen in the water is proportional to iodine titration with thiosulfate (S2O3 -2) solution. The amount of oxygen can be calculated from the titer where 1 mole of oxygen reacts with 4 moles of thiosulfate. Increase in Water Temperature Changes in water temperature can kill fish especially when the temperature levels are above or below fish’s tolerance levels. Rapid changes in temperature in water bodies due to human activities can cause fish kills. In addition, seasonal changes in temperature can cause fish deaths. Increase in water temperature indicates a source of thermal pollution or unnatural warming. Thermal pollution results from human activities that affect water temperature such as industries and runoff that enter rivers and lakes. Temperature influences the metabolism and growth rate of aquatic organisms as well as oxygen solubility in water. At increased temperatures, plants grow and die fast and hence leave behind matter that needs oxygen for decomposition (Lushchak, 2011). Temperature of all samples should be obtained by use of thermometric technique at the sampling site. A calibrated mercury thermometer should be used. A study conducted by Lushchak (2011) showed that changes in water temperature induce oxidative stress in fish and other aquatic animals. PH PH of the samples can be obtained using potentiometric technique. The PH meter should be calibrated before the PH of the samples is taken. Total Suspended Solids (TSS) Suspended solids encompass silt, clay, fine particles of organic as well as inorganic matter. Suspended solids are deemed as form of pollution since water having high concentration of suspended solids negatively impacts the development of aquatic fauna and flora. During the analysis, filtering of known quantity of sample should be done using filter paper. Filter paper should then be dried and TSS determined (Heil et al, 2005). Total dissolved solids (TDS) This will measure all substances dissolved in the water. TDS should be calculated by use of an Electrical Conductivity (EC) meter. Biochemical oxygen demand (BOD) The samples should be incubated. Decrease in levels of dissolved oxygen concentration over the incubation produces the quantity of biochemical oxygen demand (Lusk et al, 2005). Analysis of Heavy Metals Analysis of heavy metals in particular Mercury will be necessary because of ABChemicals that manufacture methyl-mercury. The obtained samples will be analysed using Atomic Absorption Spectrophotometer to examine the concentration using a mercury cathode lamp (Flack, 1997). The Spectrophotometer should be calibrated before the sample is injected. Gas chromatography This technique can be used to determine the several different organic compounds in the water Discussion Contaminated and polluted water contains low levels of dissolved oxygen (DO) as a result of heavy biological oxygen demand(BOD) and chemical oxygen demand(COD) placed by effluents waste materials discharged into the water (Paerl et al, 1999). There are various reasons for death of fish such as inadequate DO, extreme water temperatures, abrupt changes in water salinity/temperatures, discharge or spilling of toxic substances in the water, existence of microorganisms, diseases or from bodily injury. Evidence from previous studies show that low oxygen levels in the water as well as toxicity of the water are some of the major causes of fish death (Paerl et al, 1999). Low levels of oxygen in surface water can be attributed to several factors such as: Increased water temperatures: Due to the fact that solubility of gases in water which includes oxygen reduces with rising temperatures. DO levels tend to reduce as temperatures of the water increases and this explains the significance of temperature measurement Excess nitrogen: This can cause reduced DO. This is mostly attributed to affluent from sewage treatment plant. If the toxicity of the river came from the Styxton Sewage Plant, a spike in nitrate will be noted Small et al (2014). Excessive biochemical oxygen demand (BOD): The organic substances in waste water discharged in the river and sediments take on more oxygen during decomposition by the aerobic bacteria. A study conducted by Small et al (2014) indicated that hypoxic incidents can occurs within days due to increased organic matter and this can cause sudden death of aquatic animals. Sediment oxygen demand (SOD): Oxygen ingested by sediment microbes can have an impact on levels of DO. A previous study found out that high levels of SOD in water can cause decrease in oxygen levels and this can cause death of aquatic animals. This is mostly likely to as a result of leakage from Styxton Sewage Plant (CCMP, 2001). In addition, small decrease in PH and increased DOC can cause death of aquatic animals due to hypoxia. Reduced levels of PH reduce the affinity of fish’s gills for oxygen and hence this has a direct effect on hypoxia tolerance. Decreased PH in the water is likely to indicate high concentrations of dissolved organic acids, carbon dioxide or toxic polyphenols (Small et al (2014). If the fish kill was as a result of methyl-mercury, presence of mercury will be detected in the water samples (Lusk et al, 2005). Conclusion Contaminated water has decreased levels of dissolved oxygen (DO) due to heavy biological oxygen demand as well as chemical oxygen demand. In this case, this could have resulted from waste materials from the sewage discharged in the river and affluent from the brewery. The contamination of the water may have also occurred due to mercury in the water. All these are possible causes of the fish kill in Styx River. The analysis of the physio-chemical parameters of the samples can be used to determine the possible cause of the fish kill. Recommendations Field instruments for measuring dissolved oxygen, pH and temperature should be calibrated appropriately and calibration records retained. These measurements should be carried out during the sampling time (Fast, 2008) Analysis of samples for ammonia and B.O.D. determinations should be done during day of sampling There should be improved monitoring of surface water discharge (Fast, 2008) Gas chromatography technique should be used to determine the several various organic compounds in the water because the basis of the technique is that various organic compounds bind to the same polymer with varying binding strengths The effluent discharged in the water should be irradiated with UV light to kill the probable microorganisms in the river It should be ensured that the physio-chemical parameters of both the surface and ground water in the river are analysed frequently to ensure that they are within the FMENV and WHO acceptable limits (Fast, 2008). References CCMP, 2001. Peconic Estuary Program Comprehensive Conservation and Management Plan. Fast, M, 2008, Aquatic Diseases and Immunology, School of Marine and Atmospheric Sciences, SUNY Stony Brook, N.Y. Flack D, 1997, Amperometric Oxygen Electrodes, Current Separations, 16(1). FAO, 2015, Water quality and fish health, FAO. Heil, C. A., Glibert, P. M., Al-Sarawl, M. A., Faraj, M., Behbehani, M., & Husain, M, 2001, First record of a fish-killing Gymnodinium sp bloom in Kuwait Bay, Arabian Sea: chronology and potential causes, Marine Ecology-Progress Series, 214, 15. Lamotte Company, 2012, Chlorine Residual Testing Fact Sheet, Chlorine Residual Testing Fact Sheet, CDC SWS Project. Lusk D, Rich E & Bristol R, 2005, Methylmercury and other Environmental Contaminants in Water and Fish Collected from Four Recreational Fishing Lakes on the Navajo Nation, 2004, U.S. Department of the Interior, Fish and Wildlife Service, or U.S. Geological Survey. Olajumoke A, Oluwatosin A, Olumuyiwa O & Abimbola F, 2010, Impact Assesment of Brewery Effluent on Water Quality in Majawe, Ibadan, Southwestern Nigeria, 2(5). O’Sullivan D, 1995, Fish Kills: Causes and Investigation in Australia, Aquaculture Sourcebook 13, Key Centre for Aquaculture, University of Tasmania Launceston. Paerl, H.W., J.L. Pinckney, J.M. Fear, and B.L. Peierls, 1999, Fish kills and bottomwater hypoxia in the Neuse River and Estuary: reply to Burkholder et al, Marine Ecology Progress Series, 186: 307-309. Small K, Kopf R, Watts R & Howitt J, 2014, Hypoxia, Blackwater and Fish Kills: Experimental Lethal Oxygen Thresholds in Juvenile Predatory Lowland River Fishes, PLoS One, 9(4): e94524. Tomarken J, 2016, Investigation of Fish Kills Occurring in the Peconic River - Riverhead, N.Y. Spring. Read More

Chlorine kills fish and hence it could be a possible cause of the fish kill since the chlorine kills fish just like it kills germs during disinfection. Liquid chemical OTO (othotolidine) can be used to test chlorine whereby when added in the water the color of the water turns yellow if there is chlorine (Lamotte Company, 2012). Raw Sewage Sewage consists of domestic and industrial wastes and is more than 99 percent water and the other percentage consists of ions, solid suspensions as well as harmful bacteria and other microorganisms.

Sewage is a main carrier of diseases due to human wastes in this case from the village of Stxyton and toxins from industrial wastes and in this case the Riverside Brewery and AB Chemicals. This is collaborated in Guardian (2014) where in Glastonbury water quality was harmed and also fish were killed due to sewage leak in the river. Surfactants These are substances used in industries in cleaning and all and they act by lowering the surface tension of water. Surfactants in this case study could be originating from surfactants used in cleaning the sewage as well as in ABChemicals.

The surfactants have toxic effects on aquatic organisms and hence they could be the possible cause of the fish kill (FAO, 2015). Ammonia Ammonia is a possible contaminant in this case. Ammonia pollution can originate from the sewage and well as industry effluent from the ABChemicals Company. Ammonia is in form of ammonia ion in water and readily diffuses across the tissue barriers of the fish and hence it is potentially toxic to the fish. Ammonia has specific toxic effects on the brain and this is the reason why there are nervous symptoms during ammonia toxicity to the fish.

Ammonia has a particular toxic effect on the brain; this is why nervous symptoms during ammonia toxicity (FAO, 2015). An example of water contamination by ammonia from sewage occurred when human waste polluted nearby river White-lake. During Glastonbury festival, a steel tank that was used for storing sewage for people who attended the festival leaked into river White-lake which harmed the fish as well as water quality. The investigation found out that high levels of ammonia entered the water and this is what caused the harm.

Sampling Step 1 Take water samples in the immediate area of the dead/dying fish Using two clean 1-litre bottles, sample water close to the shore but not the stagnant water but ensure that surface water is included Step 2 A few fish should be examined for external abnormalities like skin discoloration and distended, pale or darkened gills. Step 3 Discharges upstream of the kills should be located. Both sides of the river should be explored carefully and all inputs suspected to have polluting substances should sample.

Samples should be taken upstream of any likely pollution source because this assists in detecting changes in quality of water. Water sample from the river will be collected at the beginning of the river because less oxygen occurs at the beginning of the river. Sediment samples from river. Sediments sample should be collected from the edges and the middle of the river because contaminants reduce as we get deeper in the river. Collection of organic samples for example DO, COD and oil grease should be done using glassware whereas plastic containers should be used to collect heavy metals and other parameters (TomarkenJ, 2016).

Literature shows that it is important to soak the sampling containers in HNO3 for 24hours and clean them using laboratory detergent, rinse with tap water and lastly rinse using de-ionised water to ensure that there is no contamination of the containers (CCMP, 2001). Analysis Determination of Dissolved Oxygen using Winkler Titration This test is used to measure the concentration of dissolved oxygen in water samples. In this method, iodide (I−) is added to a water sample. Oxygen dissolved in the water oxidizes the iodide ion (I-) to iodine.

The amount of iodine that is formed is determined by titrating using a standard thiosulfate (S2O3 -2) solution.

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