Modeled underwater sound levels in the Pan-Arctic due to increased shipping: Analysis from 2013 to 2019.

The loss of Arctic sea ice is one of the most visible signs of global climate change. As Arctic sea ice has retreated, Arctic marine shipping has increased. The Pan-Arctic's unique underwater acoustic properties mean that even small increases in ship traffic can have a significant effect on the ambient soundscape. This study presents the first long-term, basin-scale model of shipping noise in the Pan-Arctic with a focus on a few select sub-regions. The Arctic Ship Traffic Database from the Protection of the Arctic Marine Environment is used in this study to model the locations and source levels from ships operating in the Pan-Arctic between 2013 and 2019. The acoustic footprint of these ships is explored temporally for the entire basin as well as for the select large maritime ecosystems of the Barents Sea, the Northern Bering-Chukchi Sea, and Baffin Bay. From 2013 to 2019, modeled shipping noise propagating underwater broadly increased between 5-20 dB across the Pan-Arctic, but more specific results in sub-regions are presented and discussed.

Multidecadal increase in plastic particles in coastal ocean sediments.

We analyzed coastal sediments of the Santa Barbara Basin, California, for historical changes in microplastic deposition using a box core that spanned 1834-2009. The sediment was visually sorted for plastic, and a subset was confirmed as plastic polymers via FTIR (Fourier transform infrared) spectroscopy. After correcting for contamination introduced during sample processing, we found an exponential increase in plastic deposition from 1945 to 2009 with a doubling time of 15 years. This increase correlated closely with worldwide plastic production and southern California coastal population increases over the same period. Increased plastic loading in sediments has unknown consequences for deposit-feeding benthic organisms. This increase in plastic deposition in the post-World War II years can be used as a geological proxy for the Great Acceleration of the Anthropocene in the sedimentary record.

Long-term aging and degradation of microplastic particles: Comparing in situ oceanic and experimental weathering patterns.

Polypropylene, low-density polyethylene, and high-density polyethylene pre-production plastic pellets were weathered for three years in three experimental treatments: dry/sunlight, seawater/sunlight, and seawater/darkness. Changes in chemical bond structures (hydroxyl, carbonyl groups and carbon-oxygen) with weathering were measured via Fourier Transform Infrared (FTIR) spectroscopy. These indices from experimentally weathered particles were compared to microplastic particles collected from oceanic surface waters in the California Current, the North Pacific Subtropical Gyre, and the transition region between the two, in order to estimate the exposure time of the oceanic plastics. Although chemical bonds exhibited some nonlinear changes with environmental exposure, they can potentially approximate the weathering time of some plastics, especially high-density polyethylene. The majority of the North Pacific Subtropical Gyre polyethylene particles we measured have inferred exposure times>18months, with some >30months. Inferred particle weathering times are consistent with ocean circulation models suggesting a long residence time in the open ocean.

Developmental toxicity and DNA damage from exposure to parking lot runoff retention pond samples in the Japanese medaka (Oryzias latipes).

Parking lot runoff retention ponds (PLRRP) receive significant chemical input, but the biological effects of parking lot runoff are not well understood. We used the Japanese medaka (Oryzias latipes) as a model to study the toxicity of water and sediment samples from a PLRRP in Morehead City, NC. Medaka exposed in ovo to a dilution series of PLRRP water had increased odds of death before hatching, but not teratogenesis or delayed hatching. Next, we adapted a long-amplicon quantitative PCR (LA-QPCR) assay for DNA damage for use with the Japanese medaka. We employed LA-QPCR to test the hypotheses that PLRRP water and sediments would cause nuclear and mitochondrial DNA damage with and without full-spectrum, natural solar radiation. Fluoranthene with and without natural sunlight was a positive control for phototoxic polycyclic aromatic hydrocarbon-induced DNA damage. Fluoranthene exposure did not result in detectable DNA damage by itself, but in combination with sunlight caused significant DNA damage to both genomes. PLRRP samples caused DNA damage to both genomes, and this was not increased by sunlight exposure, suggesting the DNA damage was unlikely the result of PAH phototoxicity. We report for the first time that PLRRP-associated pollutants cause both nuclear and mitochondrial DNA damage, and that fluoranthene-mediated phototoxicity results in similar levels of damage to the nuclear and mitochondrial genomes. These effects may be especially significant in sensitive marine ecosystems.

Patient-reported outcomes in end-of-life research in pediatric oncology.

OBJECTIVE: The purpose of this review of published literature was to identify the number and focus of empirically based papers that included research methods used to directly solicit patient-reported outcomes (PRO) from pediatric oncology patients at end of life. METHODS: Key terms including "pediatric or child and oncology or cancer and end of life or palliative or hospice or dying" were used with five data bases (PubMed, Ovid, Cochrane, PsycInfo & PsycArticles, and CINAHL) for English language literature published between January, 2001 and June, 2006. All retrieved documents were independently reviewed by a panel of six (nurses, physicians, and one psychologist) with backgrounds in pediatric oncology. RESULTS: Thirty-five publications were identified but nine (25.7%) were eliminated from the analysis as they did not meet inclusion criteria. Of the remaining 26, four (15.4%) included patient-reported outcomes, six (23.1%) included parent only-reported outcomes, and five (19.2%) included staff only-reported outcomes. Nine (34.6%) were retrospective medical record reviews. Two (7.7%) included parent and record review data or parent and physician reports. CONCLUSIONS: Empirically-based end-of-life publications in pediatric oncology are relatively few in number and nearly 85% of completed studies do not include PRO.