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Local Nurse Explores Link Between Algal Bloom And Human Health

Apr 25th, 2016 | Category: MDC News

Harmful Algal Bloom

Rachel Truxall was inspired by her daughter’s science-fair project on microplastics in the water last spring. When daughter Bella found microplastics in the family’s tap water, as well as in bottled water and other water samples, her mom became concerned.

She also became motivated to learn if any data was available on human health associated with water quality.

A registered nurse, Rachel was taking an environmental health graduate class at the University of West Florida at the time, in which there was considerable discussion about water quality. That class discussion reminded her of news headlines closer to home in the Indian River Lagoon.

When her husband, Chad Truxall, executive director of the Marine Discovery Center, came home from work one day and asked why a person with a master’s degree in public health would be studying dolphins in the lagoon, the question prompted more exploration. They learned that an epidemiologist from Harbor Branch Oceanographic Institute was studying the link between dolphins, the environment and human health. That gave Rachel Truxall a focal point in pursuing a graduate degree in public health.

She sat down with Lisa D. Mickey of the Marine Discovery Center to talk about her recent research exploring the effect of water quality and algal blooms in the Indian River Lagoon on human health. Here’s what she had to say:

MDC: What was your focus when you launched into this research?
Truxall: My objective was to see if algal blooms would have an effect on human health. And with recent manatee, pelican and dolphin deaths, and more recent fish kills, I wanted to know if there was a possibility that human health could also be affected? I wanted to see if there was a relationship between poor water quality and our health.

MDC: What was your conclusion?
Truxall: There’s definitely a possible correlation with these things. It was evident in 2004-2006, and again in 2011-2012. There were possible associations between both the poor water quality and human health during those years. Following the four hurricanes that struck this region in 2004, vibriosis cases – bacterium that live in estuarine waters — started to spike as water quality diminished. Individuals experiencing vomiting and diarrhea didn’t always see their symptoms as water-related issues. During the 2012 brown tide event, water quality also decreased. We could see that in the turbidity of the water (lack of clearness) and the effect of dissolved oxygen in the water. During that same time, there was an increase of water-borne illness, but a lot of these illnesses could have been very under-reported. When you look at the higher number of illnesses during those events, you have to wonder what the true numbers are?

MDC: You didn’t have a lot of research from which to draw, so this must have been like starting from scratch to support your hypothesis.
Truxall: I started by getting water quality data from Volusia County Environmental Management, and then I decided to focus on the Indian River Lagoon water here in Volusia County. I looked at water-borne cases of illnesses in Volusia County. This was really a first study, so the focus became more about the possibility of finding a link between the water and human health, as well as to motivate further studies.

MDC: What did you learn from the scientist conducting dolphin research in the lagoon?
Truxall: He identified dolphins with higher mercury levels in the northern Indian River Lagoon and he also found antibodies to the West Nile virus and toxoplasmosis in dolphins.

MDC: Dolphins are “sentinel species” and can alert humans if there is something harmful going on in our environment. What can we learn from them?
Truxall: Scientists believe that atmospheric mercury in the northern Indian River Lagoon is responsible for dolphins having higher levels of mercury than in other parts of the lagoon. Winds come here from other parts of the county, state and country, so we get their pollution. We can look to issues that dolphins are facing as a warning to us.

MDC: How does the knowledge that dolphins now have antibodies for such human diseases as West Nile virus and toxoplasmosis help us?
Truxall: It could help us better understand how diseases can be spread to humans. Even if the animals don’t get the disease, they’re producing antibodies, so they’re still affected in some way. Can these diseases go back and forth? It may be a concern for handlers of dolphins or humans spending time in the same water. And it can work both ways. Are we giving them diseases?

MDC: What is an HAB and why do we care about it?
Truxall: HAB stands for Harmful Algal Bloom and they produce toxins that can harm people. For example, if you eat shellfish affected by red tide, you can get toxic shellfish poisoning. Another type is brown tide, which is eco-system disruptive. The disruption it causes to the marine ecosystem is what causes illnesses and deaths.

MDC: What is nutrient pollution and how does it affect us?
Truxall: It can be storm-water runoff, too much nitrogen and phosphorus from fertilizers, and also leaking septic tanks. Climate change and meteorological events, such as El Nino, can also lead to warmer water, which helps bring about algal blooms. The Indian River Lagoon has been warmer than usual and the algal blooms we’re having right now came before we even entered the summer months. What’s going to happen when it gets even warmer?

MDC: In one national study, you noted that 458 cases of suspected and confirmed human bloom-associated illnesses and 175 animal morbidity and mortality events were attributed to HABs. Why?
Truxall: Some bacteria in the water can produce toxins. It can be in fresh or salt water. Children are also more at risk because they have lower body weight, can be more active in the water than adults and more susceptible to toxic effects on their development. You can get vibriosis from recreating in the water in such activities as swimming or wakeboarding. Water that gets into cuts, wounds or any portal of entry in the human body can be a way that vibriosis occurs. You can get a vibriosis infection from eating contaminated shellfish. And if water quality is poor, you also have to think about family pets, such as dogs swimming in the water.

MDC: Were you surprised at the severity of health impacts from something like algae?
Truxall: Yes. With algal blooms, you mostly hear about fish kills, manatee and dolphin deaths, but I never heard anything about people getting sick. When I learned that the increase in algal blooms correlated with the decrease in water quality, I was shocked that no one had discussed the possibility that the algal blooms could also affect humans.

MDC: As a registered nurse, how does this affect the way you deal with people who recreate in the waters of the lagoon?
Truxall: I’m no longer a pediatric nurse, but if I were and a child came in with a rash or G.I. [gastrointestinal] symptoms, I would ask if they had been recreating in the water or eating anything from the Indian River Lagoon? Especially if I were aware of a current algal bloom, I think it’s important that human health clinicians don’t separate from the environmental side of things. It’s a new push, but in the past, those two sides most often weren’t considered together. Now, we have to realize that human health and the environment are interdependent.

MDC: So how can we get better at that?
Truxall: We need some type of outreach to physicians who practice in both pediatric and primary care along the Indian River Lagoon and educate them about what type of water-borne illnesses may occur and the symptoms associated with the infection. Also, there could be some type of messaging system that goes out to health care providers telling them if a fish kill has just happened or an algal bloom is occurring in a nearby community. If a child came in with certain symptoms, we could ask if they had been around the lagoon and then send the patient for the proper lab tests.

MDC: If you were a health care provider in Brevard County where they had the massive fish kills, what would you be looking for?
Truxall: You would likely see vomiting, diarrhea and a rash. And in severe cases, there could be complications from things like vibriosis. It can be more complex if individuals have compromised immune systems. A few years ago, one individual died as a result of a vibrio infection.

MDC: What can the public do to protect themselves as they recreate in the water?
Truxall: Proper hand washing helps a lot. If there are any warnings in the Indian River Lagoon, individuals should avoid eating any fish caught that day from the area. If you’re in the water and you’re handling fish, wash your hands as soon as you’re done, especially before you eat or place your hands near your face. I think we’re now at a place where people who live around the water need to stand up and say they won’t tolerate poor water quality. We also need to push for proper legislation to assure that our water is being conserved and restored to safe measures.

MDC: It sounds as if there has been a real disconnect between health care providers and what’s occurring in our environment. How can we bridge the gap?
Truxall: It’s a newly realized disconnection. I think we have to figure out a plan for better information sharing on both the environmental and the marine side to physicians and veterinarians. If we can do that, we’ll get more collaboration between both sides.

MDC: How does what you have learned affect how you do your job moving forward?
Truxall: It really affected me to see how the environment can have an impact on people and it’s important to identify the effect the environment has on our health. We can estimate how our economy is affected if tourism declines and people are no longer fishing and boating or recreating on the water, but we can’t estimate long-term health-care costs. I don’t think we can wait until it becomes a crisis like what happened in Flint, Michigan. Citizens must be proactive, not reactive to problems in the environment. If they wait, the result may be negative health effects.

MDC: Because of the water issues in Michigan, the public now has a greater awareness about harmful water quality. How does that affect what we’re learning about water quality issues in the Indian River Lagoon?
Truxall: What you can learn is that water quality is vitally important to our health. The poor water quality in Michigan allowed lead to leach from pipes and make people sick. Poor water quality here in the lagoon can also lead to disease among humans. I hope what we learn from Michigan, as well as from my study or future studies, is the importance of water. We can’t survive without it. Our lagoon provides nutrition, food and livelihood. If fishermen can’t fish, they can’t provide for their families. There’s a negative trickle-down effect whenever water quality suffers. The water crisis in Michigan is a tragedy. Let’s not do the same thing with the Indian River Lagoon.

Click for Truxall’s Water Quality & Waterborne Illness Abstract