Aerosol Toxins Emitted by Harmful Algal Blooms Susceptible to Complex Air–Sea Interactions

Abstract

Critical research is needed regarding harmful algal blooms threatening ecosystem and human health, especially through respiratory routes. Additional complexity comes from the poorly understood factors involved in the physical production of marine aerosols coupled with complex biogeochemical processes at ocean surfaces. Hereby using a marine aerosol generation tankfive bubble-bursting experiments (with contrasting incubation times and, likely, physiological microalgal states) were run to investigate simultaneously the concentrations of the toxins, synthesized by a natural Ostreopsis cf. ovata bloom, in suspension in the water and in the atmosphere. The first two experiments (EXP1–2) were run with moderate levels of O. cf. ovata cell numbers (ca. 105 cells·L–1) and total toxin in suspension (4 × 106 pg·Lwater –1) obtained at an early phase of the bloom. After 0.75–4 h incubation, toxin concentration in the aerosols accounted for 49–69 pg·Lair –1. By striking contrast, three experiments (EXP3–5)conducted with samples collected two weeks later with higher cell abundances and higher toxin concentration in the seston (respectively, about 1 × 106 cells·L–1 and 2 × 108 pg·Lwater –1) and incubated for 21 hshowed about 15-fold lower atmospheric concentrations (3–4 pg·Lair –1), while important foam accumulation was observed in the water surface in the tank. Offline spectroscopic analysis performed by proton-nuclear magnetic resonance spectroscopy showed that the particulate organic carbon in the water was drastically different from that of bubble-bursting aerosols from the tank experimentssuggesting a selective transfer of organic compounds from seawater into the atmosphere. Overall, the results suggest that aerosol production and diffusion of marine toxins in the atmosphere are regulated by complex interactions between biological processes and air-sea aerosol production dynamics.

Phycotoxin-Enriched Sea Spray Aerosols: Methods, Mechanisms, and Human Exposure

“…Another interesting observation made during the natural seawater experiment was the high foam stability (Figure S12). Medina-Peŕez et al 88 observedusing Ostreopsis cf. ovata cultures in a SSA generatora very large countereffect of foam stability on the aerosolization of amphiphilic, surface-active ovatoxins.…”

Sea Ice Microbiota in the Antarctic Peninsula Modulates Cloud-Relevant Sea Spray Aerosol Production

“…Bubble-bursting SSA generation experiments were performed on a 75 L airtight high-grade stainless-steel cylindric tank (or chamber) illustrated in Figure S1 in Medina-Peŕez et al (2020). The tank (named OLLA) has internal dimensions (50 cm height, 44 cm diameter) designed to allow research on different marine ecosystems requiring a high volume of water for a variety of chemical and biological parameters (e.g.…”

“…The tank (named OLLA) has internal dimensions (50 cm height, 44 cm diameter) designed to allow research on different marine ecosystems requiring a high volume of water for a variety of chemical and biological parameters (e.g. Park et al, 2019;Park et al, 2020;Medina-Peŕez et al, 2020). With a peristaltic pump, seawater was circulated through a Teflon tube from the bottom to the top of the tank where it was dropped as a plunging jet over the water surface at a flow rate of 12 L min −1 : in this way entrained air formed bubbles that -by bursting processesproduced spray aerosols.…”

“…For instance, in early laboratory studies sintered glass filters of different porosity (Martensson et al, 2003;Sellegri et al, 2006;Tyree et al, 2007) and pressurized atomizers (Svenningsson et al, 2006;Taketani et al, 2009) produced SSA with size distributions very different from those of natural aerosols. After detailed investigations (Sellegri et al, 2006;Fuentes et al, 2010;Modini et al, 2013;Prather et al, 2013;Christiansen et al, 2019;Sellegri et al, 2021), the plunging water jet method has become the accepted method to reproduce marine aerosols characteristic of an oceanic whitecap (Stokes et al, 2016, Sellegri et al, 2021O'Dowd et al, 2015;Stokes et al, 2016;Medina-Peŕez et al, 2020). Briefly, air is entrained in the chamber filled with water using a vertical re-circulating water jet.…”

Leaching Material from Antarctic Seaweeds and Penguin Guano Affects Cloud-Relevant Aerosol Production

“…Bubble-bursting sea spray aerosol (SSA) generation experiments were performed in a stainless steel 70 L tank. The "OLLA" aerosol primary chamber is a tank of 55 cm height by 44 cm diameter, this allow to use high volumes of waters (about 70 L) that are necessary to research different chemical and biological parameters (Park et al, 2019(Park et al, , 2020Medina-Pérez et al, 2020). The water goes around via a teflon tube from the bottom to the top of the tank via a peristaltic pump (flow rate 12 L min −1 ): a plunging jet over the surface of the water entrain air and form bubbles.…”