Hundreds of millions of tons of mineral dust are transported thousands of miles through the atmosphere from the Sahara and Sahel of Africa to the Caribbean and the Americas every year. Might African dust play a role in coral reef declines in the Caribbean region, and does it have a negative effect on human health?
To begin to answer those questions, we first collected air samples in the dust source region (Mali) and off the coast of Africa (Cape Verde Islands) and at downwind sites in Trinidad and Tobago (southeastern Caribbean) and St. Croix (U.S. Virgin Islands) during dust incursions. Next, we identified and quantified the chemical contaminants [pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and metals] and microorganisms in dust air masses and quantified the inhalable fraction of dust (PM2.5, PM10) and total suspended particulates in sampled air. Preliminary tests of the bioaccessibility of biotoxic and bioactive metals in humans have been completed.
Chemical contaminants [pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and metals] and microorganisms have been identified in dust air samples from all sites.The next logical step is to test the toxicity of dust on marine organisms, microorganisms including pathogens, and humans (human cells and fluids).