Ocean Acidification Increases Copper Toxicity to the Early Life History Stages of the Polychaete <i>Arenicola marina</i> in Artificial Seawater

The speciation and therefore bioavailability of the common pollutant copper is predicted to increase within the pH range anticipated under near-future ocean acidification (OA), hence the potential exists for copper toxicity to marine organisms to also increase. We investigated the impact of OA (seawater pH values of 7.77 (pCO₂ 1400 μatm) and 7.47 (pCO₂ 3000 μatm)) upon copper toxicity responses in early life history stages of the polychaete <i>Arenicola marina</i> and found both synergistic and additive toxicity effects of combined exposures depending on life history stage. The toxicity of copper on sperm DNA damage and early larval survivorship was synergistically increased under OA conditions. Larval survival was reduced by 24% when exposed to both OA and copper combined compared to single OA or copper exposures. Sperm motility was negatively affected by both OA and copper singularly with additive toxicity effects of the two stressors when combined. Fertilization success was also negatively affected by both OA and copper individually, but no additive effects when exposed as combined stressors were present for this stage. These findings add to the growing body of evidence that OA will act to increase the toxicity of copper to marine organisms, which has clear implications for coastal benthic ecosystems suffering chronic metal pollution as <i>p</i>CO₂ levels rise and drive a reduction in seawater pH

Role of Marine Snows in Microplastic Fate and Bioavailability

Microplastics contaminate global oceans and are accumulating in sediments at levels thought sufficient to leave a permanent layer in the fossil record. Despite this, the processes that vertically transport buoyant polymers from surface waters to the benthos are poorly understood. Here we demonstrate that laboratory generated marine snows can transport microplastics of different shapes, sizes, and polymers away from the water surface and enhance their bioavailability to benthic organisms. Sinking rates of all tested microplastics increased when incorporated into snows, with large changes observed for the buoyant polymer polyethylene with an increase in sinking rate of 818 m day^–1 and for denser polyamide fragments of 916 m day^–1. Incorporation into snows increased microplastic bioavailability for mussels, where uptake increased from zero to 340 microplastics individual^–1 for free microplastics to up to 1.6 × 10⁵ microplastics individual^–1 when incorporated into snows. We therefore propose that marine snow formation and fate has the potential to play a key role in the biogeochemical processing of microplastic pollution

Mangan_et_al_ProcRoyalB_2017_RawData

This file contains all raw data used to produce the figures and tables within the article. Supplementary data is within a separate file

Mangan_et_al_Supplementary_ProcRoyalB_2017_RawData

This file contains all the data used to produce the supplementary material for this article

Sample characteristics by NHANES wave.

*<p><b>Note: estimate based on survey weighted age, sex ethnicity adjusted logistic models in adults aged 18–74 years with valid BPA measures, comparing NHANES wave.</b></p

Distribution of Bisphenol A concentration (ng/ml) in NHANES 2003/04 and 2005/06.

<p>Note: Boxes represent upper and lower quartiles with median line, whiskers end at 5^th percentile (below LLOD) and 95^th percentile of distribution. Data from adults aged 18 to 74 years.</p

Fully adjusted^* survey weighted model estimates (odds ratios with 95% confidence intervals) of disease associations per standard deviation increase of Bisphenol A concentration: adults aged 18 to 74.

*<p>models adjusted for age, gender, ethnicity, education, income, BMI, waist circumference, smoking status and urinary creatinine.</p

Tables3_24hourpHmonitoring.csv from Fluctuating seawater pH/<i>p</i>CO₂ regimes are more energetically expensive than static pH/<i>p</i>CO₂ levels in the mussel <i>Mytilus edulis</i>

Seawater pH over 24 hours of exposure for the four treatments

Disease prevalence, and survey weighted, age, gender and ethnicity adjusted model estimates (odds ratios with 95% confidence intervals) of associations with per standard deviation increases of Bisphenol A concentration with adjustment for urinary creatinine: adults aged 18 to 74.

<p>Disease prevalence, and survey weighted, age, gender and ethnicity adjusted model estimates (odds ratios with 95% confidence intervals) of associations with per standard deviation increases of Bisphenol A concentration with adjustment for urinary creatinine: adults aged 18 to 74.</p

Supporting information from Fluctuating seawater pH/<i>p</i>CO₂ regimes are more energetically expensive than static pH/<i>p</i>CO₂ levels in the mussel <i>Mytilus edulis</i>

Additional methods and seawater chemistry dat