Date of Award
Atmospheric fine particulate matter (PM2.5) exposure poses great health risks across the globe, causing both acute and chronic illnesses in humans. Therefore, a more complete understanding of the mechanisms in which PM2.5 induces these adverse health effects is urgently needed. Oxidative stress due to PAHs and other common components of PM2.5 is a proposed mechanism for its adverse health effects. However, little is known about the actual mechanisms of PM2.5 damage in humans. This study aimed to distinguish behavioral differences in two lines of zebrafish (AB & 5D) as a result of developmental exposure to PM2.5 in order to better understand variations in its effects across these two different genetic lines. For consistent testing of a chemically similar mixture of PM2.5 a standard reference material (SRM2786) in dimethyl sulfoxide (DMSO) was prepared for the whole particle suspensions (WPS) and soluble fractions. Embryos were exposed to varying concentrations of SRM (0, 12.5, 25, 50, 100, & 200 μg/mL). After 5 days post-fertilization (dpf), the total movement of each treatment and control group was compared across 3 light phases, each lasting 5 minutes. Our results showed that the fish of the 5D line contained more instances of significantly different behavior (p≤0.05), as well as showed more consistent and sensitive responses to PM2.5 exposure. Also, embryos raised in the WPS solution had more instances of significant differences from the control group than those raised in the soluble fraction. Also, most of the significant differences occurred during the Dark Phase with a few occurring during the second light phase and none observed during first light phase. Our results show that the two strains react differently to PM2.5 and that the DMSO soluble chemicals in PM2.5 are important to in altering behavior as well as large, insoluble particles.
Necaise, Connor, "Responses to Fine Particulate Matter (PM2.5) Exposures in two Wild-Type Zebrafish Strains" (2021). Honors Theses. 1602.