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%).

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.

EPA Endocrine Disruptor Screening Program (EDSP)

In the 1990’s, some scientists proposed that certain chemicals might be disrupting the endocrine systems of humans and wildlife. A variety of chemicals have been found to disrupt the endocrine systems of animals in laboratory studies, and compelling evidence shows that endocrine systems of certain fish and wildlife have been affected by chemical contaminants, resulting in developmental and reproductive problems.