Ambient air pollution per specific land use types and activities in an urbanizing Eastern Caribbean Country, St. Kitts and Nevis

Abstract

Urban development can have negative impacts on the environment through various mechanisms. While many air quality studies have been carried out in more developed nations, Eastern Caribbean (EC) countries remain understudied. This study aims to estimate the concentrations of air pollutants in the EC nation of St. Kitts and Nevis. Transport, recreation and construction sites were selected randomly using local land use records. Pollutant levels were measured repeatedly for numerous 1-hour intervals in each location between October 2015 and November 2018. Weather trends and land use characteristics were collected concurrent to sampling. Across 27 sites, mean NO2, O3, SO2, PM10 and PM2.5 levels were 26.61 ppb (range: 0–306 ppb), 11.94 ppb (0–230 ppb), 27.9 ppb (0–700 ppb), 52.9 μg m−3 (0–10,400 μg m−3) and 29.8 μg m−3 (0–1556 μg m−3), respectively. Pollutants were elevated in high urban areas and generally significantly positively correlated with each other, with the exception of PM10. NO2 levels in construction areas were generally comparable to those in transportation areas and higher than in recreation areas. O3 levels were lower in construction than recreation and transport areas. SO2 concentrations were lower in construction and recreation compared to transport sites. Construction and recreation PM10 levels exceeded transport sites, while PM2.5 was highest in construction areas. Additional bivariate and multivariate analysis were conducted to assess whether various meteorological, temporal and land use factors including rain, tour season and urban features explained variability in air pollutant concentrations. Tourist season and specific months, more than any other factors, contributed most to variability in pollutant concentrations. These new measurements of air pollution concentrations in an understudied nation may have important implications for health outcomes among exposed EC residents, and provide critical data for future exposure and epidemiologic research and environmental policy.