Todd Miller, Michael Carvan, Gabriel Pinter
The number of lakes supporting accumulations of toxic blue-green algae (scientifically known as cyanobacteria) in the United States is rising due to changes in land use and climate. As a result there is increasing risk associated with lake recreational activities (e.g. swimming, boating), and consumption of fish. Environmental factors leading to toxin production by blue-green algae in lakes are ill-defined at time-scales relevant to human behavior and algal ecology (i.e. minutes to hours). Acute poisonings are well-documented, but chronic exposure to low levels of blue- green algal toxins in drinking water is not. This project is aimed at monitoring and modeling blue-green algal toxin production in Lake Winnebago and associated drinking water at a high temporal resolution using sensor equipped buoys and automated samplers.
Engineered metal oxide nanoparticles (NPs) such as titanium dioxide (TiO2) have been increasingly used in food products, yet their potential health effects on humans has been poorly understood. Although TiO2 is traditionally considered as non-toxic due to its high chemical stability, recent studies on mammalian models suggest that long-term exposure to low-level TiO2 NPs causes systemic genetic damage and increases the risk of cancer. Build upon these findings, this study aims to understand the potential toxicological effects of TiO2 NPs to human health using alternative animal models including the nematode C. elegans and zebrafish embryo. Toxicological effects from genetic, molecular, cellular, and organismal levels will be examined to elucidate health impacts of the nanoparticles and the potential mechanism of toxic action.
Embryonic exposure to nicotine has deleterious consequences on human development at various levels. Such exposure can lead to long term changes in the cognitive abilities and behaviors related to learning and memory. Various mammalian models have been utilized to understand how nicotine can exert such effects, but this is difficult because most mammalian behaviors and the nervous system underlying them are complex. We are studying the effects of nicotine exposure in a model vertebrate, the zebrafish, with the goal of linking behavioral abnormalities created by nicotine exposure to developmental alterations in spinal neurons and associated spinal musculature. Zebrafish embryos are sensitive to nicotine exposure (first published paper to document this; Svoboda et. al, 2002). Embryos acutely exposed to nicotine exhibit a swimming-like behavior at time when they typically do not swim. On the other hand, chronically exposing embryos to nicotine, results in paralysis. These two behavioral phenotypes point us toward candidate cell types that may be altered in zebrafish by embryonic nicotine exposure.
John Hernandez, Chelsea Weirich, Sarah Bartlett, Todd Miller
The United States Environmental Protection Agency requires regular monitoring of beaches for water quality indicators of microorganisms that may cause gastrointestinal illnesses. As a Lake Michigan coastal city, Milwaukee boasts some of the most popular beaches in the nation. To protect public health, the Miller Laboratory has partnered with the Milwaukee Health Department to conduct regular daily monitoring of Milwaukee beaches for fecal coliforms and other biological, chemical, and water quality indicators. In addition, we have worked closely with the Wisconsin Department of Natural Resources and the United States Geological Survey to construct nowcast models of water quality using high resolution climate and water quality data. This project was featured recently in the Milwaukee Journal Sentinel.