Investigating the Impacts of Ammonium Phosphate-Based Fire Retardants on Cyanobacteria (Anabaena) Growth

In recent years the effects of climate change have taken a devastating toll on ecosystems around the world. With high temperatures and extreme droughts, wildfires have become increasingly common. In order to combat these natural disasters wildland firefighters, drop millions of gallons of fire retardant on public lands and forests. These fire retardants consist of between 80%-100% ammonium phosphate which are incredibly effective as fire suppressants yet is more commonly known for its use in fertilizer. Ammonium phosphate fertilizers can lead to stream eutrophication and undesirable environmental impacts. Our research aims to address the effects of fire retardant on growth in cyanobacteria, specifically Anabaena — a filamentous, nitrogen fixing genera common to North America and responsible for many of the large, toxic cyanobacteria blooms found during summer months. We hypothesized that fire retardant, which is made up of mostly ammonium phosphate, will act similarly to ammonium phosphate fertilizer and cause an increase in growth in Anabaena cultures grown in a lab environment. After a 11-day growth curve experiment, results showed no differences in growth between microcosms treated with ammonium phosphate or fire retardant, supporting the hypothesis that fire retardants can have similar effects to ammonium phosphate-based fertilizers when released in the environment

Providence virus: a new member of the Tetraviridae that infects cultured insect cells

We identified a new member of the Tetraviridae, Providence virus (PrV), persistently infecting a midgut cell line derived from the corn earworm (Helicoverpa zea). Virus purified from these cells also productively infected a H. zea fat body cell line, and a cell line from whole embryos of the beet armyworm, Spodoptera exigua. PrV is thus the first tetravirus shown to replicate in cell culture. PrV virions are isometric particles composed of two structural proteins (60 and 7.4 kDa) that encapsidate both the genomic (6.4 kb) and the subgenomic (2.5 kb) RNAs. The monopartite organization of the PrV genome resembles that of Nudaurelia beta virus and Thosea asigna virus, members of the genus Betatetravirus. The predicted sequence of the PrV structural proteins demonstrates homology to tetraviruses in both genera. The infectivity of PrV for cultured cells uniquely permitted examination of tetravirus RNA and protein synthesis during synchronous infection. The discovery of PrV greatly facilitates studies of tetravirus molecular biology. (C) 2003 Elsevier Science (USA). All rights reserved

Cadmium Concentrations in Blood and Seminal Plasma: Correlations with Sperm Number and Motility in Three Male Populations (Infertility Patients, Artificial Insemination Donors, and Unselected Volunteers)

To investigate a possible common environmental exposure that may partially explain the observed decrease in human semen quality, we correlated seminal plasma and blood cadmium levels with sperm concentration and sperm motility. We studied three separate human populations: group 1, infertility patients (Long Island, NY, USA); group 2, artificial insemination donors (AID) (Rochester, NY, USA); and group 3, general population volunteers (Rochester, NY, USA). Information about confounding factors was collected by questionnaire. Seminal plasma cadmium did not correlate with blood cadmium (Spearman correlation, n = 91, r = −0.092, P = 0.386, NS). Both blood and seminal plasma cadmium were significantly higher among infertility patients than the other subjects studied (for example, median seminal plasma cadmium was 0.282 μg/L in infertility patients versus 0.091 μg/L in AID and 0.092 μg/L in general population volunteers; Kruskal–Wallis test, P < 0.001). The percentage of motile sperm and sperm concentration correlated inversely with seminal plasma cadmium among the infertility patients (r = −0.201, P < 0.036 and r = −0.189, P < 0.05, respectively), but not in the other two groups. Age (among infertility patients) was the only positive confounder correlating with seminal plasma cadmium. To validate our human findings in an animal model, we chronically exposed adolescent male Wistar rats to low-moderate cadmium in drinking water. Though otherwise healthy, the rats exhibited decreases in epididymal sperm count and sperm motility associated with cadmium dose and time of exposure. Our human and rat study results are consistent with the hypothesis that environmental cadmium exposures may contribute significantly to reduced human male sperm concentration and sperm motility