SCANNING ELECTRON MICROSCOPY INVESTIGATION OF STREET SEDIMENT FROM AKUMAL, A TOURIST VILLAGE ADJACENT TO THE MESO-AMERICAN REEF IN THE YUCATAN
Street sediment was collected (n=15 samples) from throughout the village to ascertain if metal particulate pollution is present. Back-scatter scanning electron microscopy (BSEM) indicates that a variety of metal–rich pollutant particles occur in samples. Zn-rich, Cr-rich and Pb-rich particles were observed. Barite was also observed. Zn and Cr-rich particles are consistent with corrosion particulate from vehicular sources. Pb-rich particles are ambiguous in origin and may be vehicular, related to fishing activities or diving activities. Barite is interpreted to be recrystallized from natural aragonite from Holocene sediment, however a coal combustion source cannot be ruled out. Particle size of metal pollutants is commonly on the order of a few to several micrometers and thus can be remobilized easily to the Meso-American reef. Results indicate that studies of stormwater runoff and some form of storm water retention should be explored. Owing to the large carbonate and carbonate sand components of sediment, Akumal provides a potentially unique setting to evaluate sourcing of urban pollution components. This investigation serves a basis for comparison to other similar settings in Mexico and the Caribbean.