ACUTE TOXICITY OF STAINLESS-STEEL AND PLASTIC MULTIPLE-USE CONTAINERS ON BARNACLE LARVAE
In the fall of 2017, I had the amazing opportunity to spend a semester taking classes and conducting research at the Duke University Marine Lab (DUML). During my time at DUML, I conducted research with the Rittschof Lab as a part of an independent research project. The aim of my project is to compare the acute toxicity of stainless-steel, to three common plastics; polyethylene terephthalate, polypropylene, and polystyrene, using barnacle larvae mortality as an indicator of toxicity.
Below you will find preliminary data from my plastic toxicity experiments, the research is still going on and the data will be updated as we finish conducting all experiments.
WHY IS IT IMPORTANT?
Since the 1970s, plastic production has increased by more than 600%, with 300 million tons produced in 2015 (Jambeck 2015). As plastic takes hundreds of years to breakdown, the increase in plastic production has led to an accumulation of unbiodegradable waste (Halden 2010), which has detrimental effects on the oceans (Jambeck 2015), wildlife (Halden 2010 and Adane and Muleta 2011), and humans (Halden 2010 and Lithner 2011). Numerous studies have discussed the “visible” consequences of plastic on animals and the environment (i.e. ingestion and/or entanglement), but few studies have examined the effects of chemicals leaching from plastics (Li et al. 2016). Plastics are composed of various monomers (Halden 2010), most of which, are understudied and lack critical information on their effects on human and animal physiology. The chemicals that leach from plastic, have the potential to destroy essential ecosystems and endanger their inhabitants, as well as poisoning the food humans consume.
Acute Toxicity Comparison
Compare the acute toxicity of stainless- steel, to three common plastics
Chemical Leaching & Temperature
Examine the toxicity of stainless-steel and plastic and high incubation temperatures
Due to the corrosive properties of seawater on metal, well water was used to conduct all toxicity experiments.
- Well water was incubated in glass, stainless-steel, polyethylene terephthalate, polypropylene, and polystyrene bottles for 24 hours at two temperature treatments (24° C and 28° C), then salinity was adjusted to 35 ppt (Kester et al. 1976).
- After adjusting salinity, a dilution series using aged filtered sea water was performed and barnacle larvae were placed into each water sample for 24-hours.
- Glass flasks were used to incubate the control water, as glass dissolves slowly in water, too slow to leach chemicals in a 24-hour period (Santonen and Stockmann 2010).
Our preliminary data suggests stainless-steel has the lowest impact on larvae, suggesting it is a safer containment material than plastic. Additionally, replacing plastic with stainless-steel would decreasing the amount of harmful toxins we release into our food, water and the environment, as stainless-steel containers are reusable and do not produce the same chemical waste as plastic.
Mortality of barnacles incubated in well water from stainless-steel bottles, was the same as that of well water incubated in glass.
At the highest concentration (1.2 cm2/ml), well water incubated in the stainless-steel bottles, had the lowest mortality, at 24°C and 28°C.
Stainless-steel had the highest LC50 (lethal concentration for 50% mortality) values at both incubation temperatures (1.215 and 1.042, respectively).
The low mortality of barnacle larvae incubated in stainless-steel water, suggests low amounts of toxins leach from stainless-steel containers.
Of the three plastics, polystyrene produced the highest mortality of Nauplii when incubated at room temperature (24°C), with a 50% higher morality than stainless-steel.
Nauplii morality during the 28°C incubation, was highest in well water incubated in polyethylene terephthalate bottles, increasing almost 2 folds from the 24°C incubation.
- Funding provided by the Rittschof Lab and the Duke Marine Lab’s Marine Science and Conservation scholarship
Halden, Rolf U. 2010. “Plastics and Health Risks.” Annual Review of Public Health 31 (1): 179–94.
Jambeck, Jenna R. 2015. “Plastic Waste Inputs from Land into the Ocean.” Climate Change 2014: Impacts, Adaptation and Vulnerability 347 (January): 1655– 1732.
Kester, Dana, Iver Duedall, Donald Connors, and Ricardo Pytkowicz. 1976. “Preparation of Artifical Seawater.” 1–10.
Lewis, H, Aaberg TM, Packo KH, Richmond PP, Blu- menkrantz MS, Blankenship GW. 1987. “Intrusion of retinal tacks.” Am J Ophthalmol 103: 672–680.
Li, Heng Xiang, Gordon J. Getzinger, P. Lee Ferguson, Beatriz Orihuela, Mei Zhu, and Daniel Rittschof. 2016. “Effects of Toxic Leachate from Commercial Plastics on Larval Survival and Settlement of the Barnacle Amphibalanus Amphitrite.” Environmental Science and Technology 50 (2): 924–31.
Lithner, Delilah. 2011. “Environmental and Health Hazards of Chemicals in Plastic Polymers and Products.” Rochman, Chelsea M., Mark Anthony
Santonen, Tiina, and Helene Stockmann. 2010. Review on Toxicity of Stainless Steel. Finnish Institute of Occupational Health.
Anjali Boyd(1)*, Beatriz Orihuela(2), and Daniel Rittschof(2)
1: Eckerd College, St. Petersburg, FL
2: Duke University, Beaufort, NC