Air pollution has been identified as the largest global environmental threat facing the world today, estimated to cause 7 - 10 million deaths worldwide annually (World Health Organisation, 2014, 2016;Yale University, ...Air pollution has been identified as the largest global environmental threat facing the world today, estimated to cause 7 - 10 million deaths worldwide annually (World Health Organisation, 2014, 2016;Yale University, 2018). Trinidad and Tobago, with a per capita GDP of USD$16310 (2019), is the most industrialised of the Caribbean islands, and like the rest of the Caribbean region is also affected by seasonal Sahara dust (PM2.5). Assessment of the air quality was done for over Trinidad’s west coast. Pollution was measured at four stations during March ‘15-May ‘16, representative of rural, urban, mixed background and industrial land uses. Annual mean PM2.5 and PM10 in ambient air exceeded the WHO guidelines for protection of public health (n = 522). PM2.5 and PM10 exceed the WHO (2006) safe limit guidelines (PM2.5 is 10 μg/m3;PM10 is 20 μg/m3) over 70% of the time sampled at urban and industrial sites. Gaseous pollutants found to be in exceedance were CO, NH3, NO2, N2O, C6H6. Nitrogen dioxide and benzene were the most prolific. A collated metric based on measurement of these pollutants yielded a statistically validated algorithm—An Air Pollution Index. The single metric can convey useful and easily understood information on air quality to the regulators and the general public.展开更多
The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline...The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline concentrations in the ambient air and the factors impacting its distribution such as land use and time of year when levels may be concerning to public health. Measurements of particulates along with meteorological parameters were made at four sites over the heavily populated west coast of Trinidad (10<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>32'N, 61<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>18'W) during March ’15-May ’16, representing rural, urban, mixed background and industrial land uses. The study found mean levels of trace metals to be highest at the industrial and urban stations. Public health exceedances (referenced to the Canadian AAQ public health standards <a href="#ref23">(Ontario-MoE, 2012)</a>) were measured for beryllium, cadmium, chromium, iron, manganese and nickel (in PM<sub>10</sub>). Iron, manganese and nickel, most associated with particulates at the industrial station, were in frequent exceedance. Beryllium—concentrated in coarse PM (PM<sub>2.5-10</sub>) with only a single measured exceedance at the mixed background station likely poses minimal threat to the health of the nearby population. Cadmium—concentrated in fine PM which peaked once only at the rural station was likely due to an irregular event within a narrow timeframe during the time of sampling. Iron and manganese were frequently above the Canadian public health threshold, but predominated in the coarse PM fraction, suggesting localised sources. Nickel, concentrated in the fine PM fraction, was frequently in exceedance particularly at the industrial station. Cadmium and nickel are genotoxic and should be regulated in order to reduce the burden of toxic carcinogens to which the population can be exposed.展开更多
文摘Air pollution has been identified as the largest global environmental threat facing the world today, estimated to cause 7 - 10 million deaths worldwide annually (World Health Organisation, 2014, 2016;Yale University, 2018). Trinidad and Tobago, with a per capita GDP of USD$16310 (2019), is the most industrialised of the Caribbean islands, and like the rest of the Caribbean region is also affected by seasonal Sahara dust (PM2.5). Assessment of the air quality was done for over Trinidad’s west coast. Pollution was measured at four stations during March ‘15-May ‘16, representative of rural, urban, mixed background and industrial land uses. Annual mean PM2.5 and PM10 in ambient air exceeded the WHO guidelines for protection of public health (n = 522). PM2.5 and PM10 exceed the WHO (2006) safe limit guidelines (PM2.5 is 10 μg/m3;PM10 is 20 μg/m3) over 70% of the time sampled at urban and industrial sites. Gaseous pollutants found to be in exceedance were CO, NH3, NO2, N2O, C6H6. Nitrogen dioxide and benzene were the most prolific. A collated metric based on measurement of these pollutants yielded a statistically validated algorithm—An Air Pollution Index. The single metric can convey useful and easily understood information on air quality to the regulators and the general public.
文摘The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline concentrations in the ambient air and the factors impacting its distribution such as land use and time of year when levels may be concerning to public health. Measurements of particulates along with meteorological parameters were made at four sites over the heavily populated west coast of Trinidad (10<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>32'N, 61<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>18'W) during March ’15-May ’16, representing rural, urban, mixed background and industrial land uses. The study found mean levels of trace metals to be highest at the industrial and urban stations. Public health exceedances (referenced to the Canadian AAQ public health standards <a href="#ref23">(Ontario-MoE, 2012)</a>) were measured for beryllium, cadmium, chromium, iron, manganese and nickel (in PM<sub>10</sub>). Iron, manganese and nickel, most associated with particulates at the industrial station, were in frequent exceedance. Beryllium—concentrated in coarse PM (PM<sub>2.5-10</sub>) with only a single measured exceedance at the mixed background station likely poses minimal threat to the health of the nearby population. Cadmium—concentrated in fine PM which peaked once only at the rural station was likely due to an irregular event within a narrow timeframe during the time of sampling. Iron and manganese were frequently above the Canadian public health threshold, but predominated in the coarse PM fraction, suggesting localised sources. Nickel, concentrated in the fine PM fraction, was frequently in exceedance particularly at the industrial station. Cadmium and nickel are genotoxic and should be regulated in order to reduce the burden of toxic carcinogens to which the population can be exposed.
