A regional survey of Jamaican surface soils has been conducted in which more than 200 samples were collected at a sample density of 1 per 64 km(2) across the island and analysed for total concentrations of 31 elements by instrumental neutron activation analysis (INAA), energy dispersive X-ray fluorescence (EDXRF) analysis and atomic absorption spectrophotometry (AAS). The aim of the survey was to begin the construction of a high-precision geochemical database to provide information on elemental levels in soils for application to environmental studies, agriculture, and human and animal health. Results on the regional scale are presented for As, Cd, Cu, Hg and Pb. Although Jamaican surface soils are enriched in several heavy metals compared with world soil means and crustal abundances, lead is of particular importance at this stage because of its occurrence in residential areas. Except for Cu, the distribution maps of these elements are highly correlated with bauxite which in Jamaica is associated with white limestone geology and residualterra rossa soils.

The Centre for Nuclear Sciences (CNS) uses a raster based geographic information system (GIS), integrated with a relational database to store information on point sampled data, including concentrations of over 50 elements and/or ions in a variety of sample materials. These data are filtered in the GIS to create surface layers and are assigned colours according to percentile ranges allowing visual inspection to be used to identify significant features and trends. The database currently contains raster map layers for soils and geologic features, point site data for water and air, and vector data for roads, rivers and streams. While data are still being added to the database interesting results are already being obtained and a few instances where the GIS was used to assist in the data interpretation are reported.

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The background levels of lead in Jamaica in soils and sediments, estimated at 37 mg kg(-1), are relatively high compared with world averages. Several areas have values in excess of this due to mineralisation and pollution. One such is the residential Hope Flats/Kintyre area in which levels of lead up to 2.5% are found in the soils and up to 8 μg kg(-1) in the water of the nearby Hope River. The blood lead levels of a sample of children were in the range 5.7-57 μg dl(-1). The high lead levels suggest a potential health risk, particularly for the children. This can be minimised by programmes which include community education, case management and abatement to reduce the lead exposure.

Most air quality studies conducted in small states of the Commonwealth including Jamaica and Namibia do not address the interaction between the two main pollutants (particulate matter and tropospheric ozone), as well as their relationship with climate change. Total suspended particulates (TSP) and tropospheric ozone were measured in Windhoek, Namibia; while only TSP was measured in Kingston, Jamaica. The observed concentrations were used together with secondary data and/or calculations of atmospheric conditions like mixing height, temperature, wind speed, relative humidity, solar radiation, and ventilation rates to determine the PM-Ozone interactions and possible relationship with climate change. The TSP concentrations were high in Kingston than in Windhoek. The ozone concentrations in Windhoek were relatively low (10 to 35 ppb). The atmospheric pollutant interactions were observed as in order of relative abundance as Kingston>Windhoek for TSP, relative humidity, mixing height, and ventilation rate; and Windhoek>Kingston for solar radiation. The morphology of particulates also showed the effect of daily activities of the domestic, traffic and industrial sectors to air quality and ultimately climate, and which need to change for realization of reduced pollution and climate effect. The particulate-ozone interactions during ozone and smog formation can, depending on the source and type of aerosols, give an indication of the contribution to climate variability.