Data for: Determination and source apportionment of major and trace elements in atmospheric bulk deposition in a Caribbean rural area
Description
Bulk deposition samples (wet + dry) were collected using five bulk rain collectors (50 L polyethylene) with a total surface area of 1.25 m2. The collectors were installed on a small building roof (about 5 m above ground) in the CEAC facilities, and acidified prior to deployment with concentrated HCl. After monthly periods the samples were collected rinsing the walls of collectors twice with distilled water and combined all into plastic bottles; then the collectors were acidified and deployed again. The samples were immediately transported to the laboratory where they were evaporated to dryness and weighed (before and after the evaporation) to obtain the mass of total deposited particles. The residual particles were stored until the chemical analysis. Determination of elements was performed by inductively coupled plasma mass spectrometry (ICP-MS, Agilent 7500a), after their acid extraction in closed microwave digestion (CEM Co., Mars X press) adding 0.25 g of sample and 12 ml of aqua regia (HCl/HNO3=3:1). A multi-elemental solution (Li, Sc, Y, In, Bi, Inorganic Ventures 71D) was added to the samples as internal standard for further determination by ICP-MS. A total of 47 elements, including 13 lanthanoid elements (La to Lu), were simultaneously quantified in all samples. The monthly atmospheric fluxes (F, in µg m-2 day-1) for the studied elements were calculated as follows: F=(C*m)/(S*T) (1) where: C is the measured concentration (in µg g-1), m is the total deposited dry mass (in g), S is the total surface area of the collectors (in m2) and T is the duration of the sampling period (in days). The atmospheric bulk deposition rate (µg m-2 day-1, hereinafter bulk deposition) was calculated by the same formula (Eq. 1) without the parameter C