I would like to begin this final blog entry by thanking everyone involved in my graduate schooling-career and everyone at the EPCHC. The support and guidance has provided me with the tools needed for success, and brought me to where I am today. Thank you!!
The featured image is a Deionized (DI) Water system from the 1980’s which is still in use today for field blanks. This method is the most sensitive form of pure water for sample collection.
Due to my 2+years of experience working in environmental testing laboratories, I have been given the task to make standards for Total Phosphorus and TKN analyses throughout my internship. These standards are made with a first and second source of quality control (QC) solutions. The QC is an important part of each analysis and determines the validity of the analysis, since the QCs have a specific known range for their results.
The image is my bench-space where I made the standards (in the smaller beakers) using the first and second source solutions – which are usually bought externally. I used the volumetric glass to measure out each solution and diluted them into 100nL of DI water – type 1 (taken from the laboratory sink, treated with UV).
Working in a laboratory setting is my passion, especially with environmental samples! It brings a sense of purpose, that the work I contribute is helping the environment and protecting our common resource. Everyone at the EPCHC is extremely warm and friendly and though I’ve spent only the past two months there, I feel like an adopted relative into their wonderful family. Their work and dedication has made the Tampa Bay estuary a role-model for the nation, as our Tampa Bay has completely recovered our seagrass populations to levels before the industrialism impact of the 1950s- late 1980s. Our story of success brings hope and guidance of sustainability to all sensitive estuary ecosystems shared with our fellow human beings.
Nutrients are an essential component for life. Though, sometimes nutrient loading (an excess of nutrients within an ecosystem in a period of time) occurs due to animal fecal excrements, fertilizer runoff, and other anthropogenic factors. An increase in nutrients are harmful and toxic to our ecosystems. When soil and water cycles are not able to keep-up and maintain the natural filtration of nutrients, it can be detrimental to all living organisms in the area (including humans).
The EPCHC routinely collects samples around the Tampa Bay to ensure the levels of nutrients are within appropriate levels. When the samples are brought in, they are acidified in order to preserve the nutrient contents. As seen in the images, about 5-10mL of sample are filtered through a small circular attachment on the syringe. They are placed into the corresponding glass tube and covered with parafilm to place into storage until the analyst is ready to run the samples.
The acidity (pH) must be around 1.6-1.9pH in order to run the analysis accurately on the machine. Before filtration, each sample must be tested for the pH levels and if they are out of range (usually higher than 2.0pH), then one drop of hydrochloric acid is added to the sample, shaken, and the pH is tested again. Usually, one drop does the trick to bring the pH back down to 1.9pH, which is the ideal level.
Laboratory analysis of our environment is crucial to quantifying the sustainability of our ecosystems. This scientific approach provides quantified evidence on the levels of our ecosystem’s health. If the levels are out of range within specific analyses, then the area where the sample was retrieved is targeted to be recovered. Thus, providing guidance where our ecosystems need assistance to ensure the sustainability of our environments.
Part of the Environmental Protection Commission of Hillsborough County (EPCHC) internship is to provide exploration for the intern into the other aspects/divisions which make up the whole of the EPCHC. During the 5th and 6th weeks of my volunteer internship, I shadowed the biological and solids analyst. In the microbiology area, I was able to witness a new form of Enterococcus verification of fecal samples. This analysis is a gram-positive bacterium that has the ability to grow in high concentrations of bile salts and sodium chloride which can be toxic, and life-threatening to humans and other animals.
TKN & TP Standards Setup
Up Close TKN & TP Standards
Sample Solids Machine
Samples in their boats
My visit with another analyst involved the Total Organic Carbon analysis. His samples were in a solid form (rather than the typical aqueous) and he needed to crush the soils and other various samples in a mortar and pestle until the samples were finely ground (like sand). Each sample was placed into a boat and placed into the Solid Sample Machine analyzer which heated the samples up with a Hydrogen carrier gas. A carrier gas is a controlled gas that is pushed through and back in the machines tubing to ensure the samples have been completely removed from the machine once the analysis has completed. In this analysis, his QC and matrix spikes (MS) successfully passed, and proceeded with his 22 samples. Each sample takes about 5-7 minutes to complete its run, making the entire analysis a time-costly one.
The remainder of my 5th and 6th week in the EPCHC lab involved TKN digestion, nutrient filtration, a retirement, and the official announcement of the Governor’s Sterling Award to the EPCHC! The Governor’s Sterling Award is a high honor awarding the agency for its accuracy and dependability. As the EPCHC is a model for the rest of the nation due to the recovery and environmental monitoring accuracy of the Tampa Bay’s ecosystem.
Rain and thunderstorms (with lightning) are common in the Tampa Bay Area. When there is rainfall, environmental samples are not collected, and therefore, samples cannot be analyzed. During the 3rd and 4th weeks in the Environmental Protection Commission of Hillsborough County (EPCHC) laboratory, there were many rainy days. So, when there are few analyses to be run, reagents and standards are made. The reagents and standards are the quality control (QC) solutions to ensure the analyses are processing correctly and producing accurate results. Laboratory Control Standards (LCS) are usually duplicated every 10-20 samples, depending on the analysis. The LCS is an important QC within every analysis as they provide an expected result per analysis and without an LCS, the run is not valid. These reagents and QCs have various expiration dates, and most commonly they need to be re-made weekly.
Standards for sulfate analysis was prepared by measuring out 0.237-0.240g (grams) of Potassium Persulfate into glass tubes on a highly sensitive scale, which is atop a marble table. The marble table and scale are calibrated and ensured to be balanced and evenly equal for accuracy. The Potassium Persulfate is kept in the glass tubes and sealed with a cap until the analyst is ready to prepare the solutions to make the QC standards.
Usually on Fridays, two runs (~35-60 samples) are combined for nutrient analysis. These samples need to be filtered before placed into the sample tubes to be analyzed. About 5-10mL (milliliters) of each nutrient sample is filtered into a glass tube, and once all the samples have been filtered then they are wrapped in this stretchable plastic called parafilm and placed into a sample refrigerator for storage until the analyst is ready to run the samples.
Another crucial portion in the laboratory is the cleanliness of workspace, tools, and collection containers. Every laboratory is different, and at the EPCHC, the containers are rinsed with UV-DI (Ultraviolet-Deionized) water 3-5 times without salt. UV-DI is pure water with little to no other materials, minerals, or contaminants. Every week, if it is helpful, I will rinse tubes, collection containers (glass and plastic), and volumetric pipettes with UV-DI then set them to dry overnight.
Every day when I leave my volunteering internship at the EPCHC laboratory, I am happy! I absolutely love working in the lab, especially within this one! I’ve never experienced such nice, down to earth people who all share a common passion for the environment.
At the beginning of April 2016 I began my internship with the Environmental Protection Commission of Hillsborough County (EPC) in their water chemistry laboratory. The staff there is extremely welcoming and down to earth. As any newbie enters into any lab, the paperwork must be accomplished before anything else. I was given a tour of the facility and all of the departments that make up the EPC. Due to my previous laboratory experience (2+ years) in water quality, they informed me that I was the most experienced and qualified intern they’ve seen in years. Also, this meant that I was able to operate laboratory procedure portions on my own, such as, creating standards, filtering samples, and preparing reagents.
The program also supports interns visiting and shadowing other departments to see how the entire operation unfolds. Part of my internship project focuses on nutrient runoff and loading into the Tampa Bay, so I will go into the field, at least once to observe how samples are collected and how they assess on-site issues. The Florida Department of Environmental Protection (FDEP) and EPC were already collaborating on nutrient management and runoff prevention, though now I believe the U.S.E.P.A. is now involved which makes my interaction (as an intern) more of a sensitive matter.
However, in the laboratory, I am learning new things every day and loving every moment! The lab already sets up my nutrient filtration station for me to go ahead and begin on my own. I filter the samples and then place parafilm over the tops of the samples that are ready to be analyzed by the machine, but stored in the fridge until needed.
TP & TKN – Lachat Machine
I am learning how to operate the Lachat Machine which analyzes Total Phosphorous (TP), Ortho-phosphates, and Total Kjeldahl Nitrogen (TKN) as seen in the image above. I have digested samples, blanks, and standards in the hood (at 365 degrees Celcius), and each digested sample (20mL) goes into another tube to have at least 2mL pass through analysis. I prepared the reagents and standards for the method and all have passed. In order to have a passing analysis, there must be 50% passing on the matrix spikes and relative duplicates.
This laboratory is one of the best environments, I’ve ever had the pleasure & opportunity to participate and experience. I look forward to acquiring more knowledge about the lab and about the Tampa Bay, a place I moved to when I was little, my home, and a place I cherish.