Hydrosphere renews its USDA permit to receive soil samples

Hydrosphere recently renewed its USDA PPQ 525A Application for Permit to Receive Soil. This allows Hydrosphere to receive soil samples from around the world in order to help clients with their toxicity testing needs. Currently, Hydrosphere is involved with a large scale long term sediment toxicity project. The twist is that the samples being tested are actually soils. We are using a hydration/aging process that we have developed in-house over the years. Using these samples, Hydrosphere will be conducting 10-day survival and growth studies with the C. tenans and H. azteca test species. 

Another Successful DMR QA Study!

Once again, Hydrosphere Research has completed the DMR-QA study with "Acceptable Results" for all test species and all test endpoints. As a lab, we are required to test unknown samples once a year and compare those results to the acceptable analyte ranges for that study. The acceptable range is based on the actual level of analyte in the unknown sample, and on the combined concentration and statistical results from the other participating labs around the country.

Pathogenic Interference in Short-Term Whole Effluent Toxicity Tests: A Case Study

Pathogen interference in Whole Effluent Toxicity (WET) testing results in unnecessary costs to National Pollutant Discharge Elimination System (NPDES) permit holders. This is a condition identified explicitly in the EPA methods by which these tests are conducted. This kind of interference can result in false positive test results which, if not identified properly, can result in wasted testing and permit violations. There are methods that can be employed to identify pathogen interference.

The discharge from Florida Power and Light’s Sanford Plant, Volusia County, Florida provides a case study for this problem. This facility has whole effluent biomonitoring requirements in their NPDES permit. 7 day chronic definitive bioassay tests are conducted on the fathead minnow, Pimephales promelas. Some of the bioassay tests conducted on the discharge from the Sanford Plant have resulted in test endpoint reductions requiring further actions on the part of the permit holder.

The patterns of these reductions have been consistent with pathogen interferences as outlined in the EPA method. In the case presented here, UV treatment was employed in order to demonstrate that this interference was occurring.  Discharge samples were split into two treatment groups: untreated and UV treated samples. Parallel tests were conducted. The test results are consistent with pathogen interference.

Table 1. Chronic P. promelas Test Results
% Effluent Untreated Effluent UV Treated Effluent
Final Survival (%) Average Dry Weight (mg/fish) Coefficient of Variance (%) Final Survival (%) Average Dry Weight (mg/fish) Coefficient of Variance (%)
0 100 0.684 5.13 100 0.670 4.45
6.25 100 0.638 4.66 100 0.640 7.77
12.5 80 0.520 42.10 100 0.701 6.56
25 100 0.612 5.17 100 0.665 5.21
50 77.5 0.522 12.39 100 0.751 6.30
100 32.5 0.247 109.6 100 0.702 2.14
IC25 51.58% >100%

A demonstration of test method interference from pathogens would provide the permit holder with evidence that a given test event was a false positive response as opposed to a permit violation.The survival and dry weight between replicates in the test dilutions are very uneven (e.g. CV 109.60%) and the coefficient of variance of the control group is relatively small (5.13%). In the UV treated effluent, the mortality is completely eliminated. Furthermore, the dry weight between replicates in the test dilutions is now very even (e.g. CV 2.14%).

Helping a client contol toxicicty and pH drift

A Hydrosphere Research client was routinely experiencing chronic toxicity to the water flea test species. Their IC25s would range from 60 to 70%. This resulted in test failures and additional testing.

Dr. Smart at the Smart Group noticed that the pH in client’s sample would typically increase over each 24-hour test period. Dr. Smart suspected that this was a contributing factor to their toxicity. In order to control pH drift, Hydrosphere designed a study using sealed glass chambers with the test organisms and small amounts of carbon dioxide. pH drift chamber

The results were dramatic. Since implementing this study design, the pH drift has been corrected and the client has passed every test with IC25s greater than 100%. Below is an example of the effectiveness of this study design.

CD with pH drift

Without pH drift controlled

CD without pH drift

With pH drift controlled


Hydrosphere Research is working with the Environmental Protection Agency to Determine the Toxicity of Diluted and Synthetic Bitumen and Other Crude Oils Likely to be Transported in the U.S.

The rising demand, production, and shipping of petroleum oils in the U.S. equates to an increased risk of spills/pipeline leaks. The spills/leaks of oil cause major challenges for safe land and water management because of toxic contaminants present in oil.  The toxicity of oils varies with the types of oil, the loading rate or concentration of oil, weathering state of oil, type of oil spill countermeasure products as well as the species and physiological status of fauna and flora.  In order to better assess risk to communities and ecosystems, continued research on oil toxicity and characterization is needed.

Thus, Hydrosphere Research will conduct a series of toxicity tests with different aquatic species in freshwater and seawater for the determination of severity of toxicity using Water Accommodating Fraction, (WAF) mixture of oil in source water generated on both fresh and weathered oils. Each fresh and weathered oil type will be characterized to determine their physical and chemical characteristics. Each generated WAF will be measured to determine quantity of oil entrained in the mixture. The main objective is to evaluate toxicity of oil, both fresh and weathered, obtained from Alberta Canada using both freshwater and marine species.

DMR-QA 35 Successfully Completed

Hydrosphere Research recently completed the Discharge Monitoring Report – Quality Assurance (DMR-QA) Study 35 with an acceptable result for all test species and all test endpoints. The DMR-QA 35 is to ensure the integrity of data submitted by the permittee for DMR reporting requirements and evaluate performance of the laboratories to analyze wastewater samples. DMR-QA Study 35 covers major and select minor NPDES permit holders. Participation in the DMR-QA plays a key role in monitoring the quality of data used to assure the integrity of the Clean Water Act’s National Pollutant Discharge Elimination System (NPDES) program. As a lab, we are required to test unknown samples once a year and compare those results to the acceptable analyte ranges for that study.   The acceptable range is based on the actual level of analyte in the unknown sample, and on the combined concentration and statistical results from the other participating labs around the country. As one Hydrosphere client put it “Having all acceptable results, makes my life easier. We can submit our data and wrap up the study without having to wait on the lab to perform corrective actions and repeat the DMR–QA studies. Knowing that Hydrosphere Research has all acceptable results just confirms that they are the right lab for our toxicity testing.”

For more information about teh DMR-QA 35, visit EPA’s site.


How do surfactants and oil effect the marine environment?

Hydrosphere Research  offered up laboratory space, equipment and supervision to a local Gainesville High School student. The student’s project was titled “How do surfactants and oil effect the marine environment?” This project was for a Cambridge Advanced International Certificate of Education(AICE) Environmental Management course taught by Margaret Paxon.

The student came to Hydrosphere initially for a lab tour and to meet the lab technician that would be helping. The student showed up every day for 4 days to monitor her experiment.

Upon presenting her project,  Ms. Paxon was quoted as saying “I thought it was a very unique and creative project that seemed like it would yield interesting results”.

The  student was quoted as saying ” it was great to have a real lab to work in. I can’t thank Hydrosphere enough for the help they gave”.

Hydrosphere is happy to help out the future scientist of the world and loves to see students interested in our work!

The Importance of Regulating Toxicity

In 2013 in El Salvador, toxicity proved fatal for hundreds of agricultural workers. The Ministry of Health estimates that since  2002 over 5,000 people have died due to kidney disease that they attribute to the lack of regulation of pesticides. The Ministry of Health is trying to push for legislation to control the amount of pesticides used. Unlike in Central America, Hydrosphere is one of the main companies that works to regulate and decrease toxicity in America.


How Toxic Is Coal Ash? A Laboratory Toxicity Case Study

Under a consent agreement among the Environmental Protection Agency (EPA) and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity because many standard test species are more sensitive than resident species, thus could provide information useful to the rule-making. However, few laboratory studies of coal ash toxicity are available; most studies reported in the literature are based solely on field investigations. This brief communication describes a broad range of toxicity studies conducted for the Tennessee Valley Authority (TVA) Kingston ash spill, results of which help provide additional perspective on the toxicity of coal ash. Integr Environ Assess Manag 2015;11:5–9. © 2014 SETAC


In 2010, the Environmental Protection Agency (EPA) proposed regulation of Coal Combustion Residuals (CCR) under the Resource Conservation and Recovery Act (RCRA), which may result in more stringent controls on the disposal of CCR, particularly fly ash, at coal-fired power plants (USEPA 2010). Clearly, there is a need for a comprehensive body of peer-reviewed scientific literature from which EPA can assess environmental impacts of CCR.

Rowe et al. (2002) provided a thorough review of research on the environmental effects of CCR disposal. A brief, independent review limited to studies that included aquatic and benthic organism exposures to ash or ash basin effluents identified only 13 published articles. Ten were field studies of benthic or fish biota in 1 lentic and 10 lotic habitats (Cherry et al. 1979; Reash et al. 1988; Lemly 1997; Lohner, Reash, Willet, Fletcher 2001; Lohner, Reash, Willet, Rose 2001; Lohner, Reash, Williams 2001; Smith 2003; Reash 2004, 2012; Otter et al. 2012); and 3 were laboratory studies (Stanley et al. 2013; Wang et al. 2013; Greeley et al. 2014a), all of which were investigations of the 2008 Tennessee Valley Authority (TVA) Kingston Fossil Plant ash spill. This imbalance between field- and laboratory-based studies is likely due to prevailing opinions that laboratory studies should predict toxic effects in the field (Lemly 1985). There is a widely held acceptance that laboratory studies are conservative (particularly in the use of test organisms that are usually more sensitive to toxicants than resident species) and provide for controlled exposure conditions that exclude the noise experienced in the natural environment (Chapman 2000; Wang et al. 2004).