Pollution characteristics, risk assessment, and source apportionment of potentially toxic elements in road dust at two industrial parks in Trinidad and Tobago, West Indies.

Potentially toxic elements can enter the environment through natural and anthropogenic processes, with the latter considered the primary contributor. Road dust samples from two industrial parks on the island of Trinidad were investigated for heavy metal content, and the pollution status, potential health risks, and source apportionment were evaluated. Samples were acid-digested and analysed by flame atomic absorption spectroscopy. The average levels of cadmium, chromium, copper, manganese, nickel, lead, and zinc in road dust at the Frederick Settlement Industrial Park were 1.14 µg/g, 15.13 µg/g, 66.42 µg/g, 768.49 µg/g, 37.95 µg/g, 55.90 µg/g, and 573.04 µg/g, respectively, while average concentrations at the O'Meara Industrial Park were 1.20 µg/g, 16.97 µg/g, 42.72 µg/g, 482.65 µg/g, 21.12 µg/g, 136.77 µg/g, and 358.70 µg/g, respectively. Contamination assessments evaluated both Fredrick Settlement and O'Meara as typically uncontaminated to moderately polluted, with the overall ecological risk deemed low at all locations. Hazard index values at all sampling areas were lower than 1, indicating no potential non-carcinogenic risks to children or adults, while the carcinogenic exposure risks for cadmium, chromium, and nickel were considered low. Principal component analysis and cluster analysis revealed two main sources of contamination for Fredrick Settlement, and three main sources for O'Meara. Based on the groupings obtained, the presence of potentially toxic elements was attributed primarily to specific anthropogenic activities within the industrial parks, with lesser contributions from vehicular-related sources.

Quantification and health risk assessment of heavy metals in residual floor dust at an indoor firing range: A case study in Trinidad, WI.

Residual floor dust at an indoor firing range was investigated for the presence of selected heavy metals, and the associated health risks (non-carcinogenic and carcinogenic) were explored. Average heavy metal concentrations decreased in the following order: Pb >> Cu >> Zn > Mn > Cr > Ni > Cd. For the examined floor dust, moderate to significant degrees of enrichment were observed for Ni, Cd, Cr and Zn while extremely high degrees of enrichment were reported for Cu and Pb. Lead was the only heavy metal that exceeded the Hazard Index value of 1 and the potential carcinogenic risks for Cd and Ni were considered acceptable. A potential carcinogenic risk existed for Cr, as denoted by a total lifetime cancer risk value greater than 10-4.

Heavy metal intake and health risk implications from consumption of dried pulses in Trinidad and Tobago, W.I.

The increase in urbanisation and industrialisation have contributed significantly to elevated concentrations of heavy metals in soils. The eventual uptake of heavy metals by agronomic crops could potentially affect human health based on consumption patterns in various regions of the globe. This study investigated the potential health risks to consumers of dried legumes in a small island developing state that rely primarily on the importation of those crops from major producers. Several varieties were analysed for selected heavy metals in which Cd and Pb were not detected and Cr was only present in certain legumes. The concentrations of Cu, Mn, Ni, and Zn were all below the established World Health Organisation (WHO) maximum permissible limit (MPL) and the target hazard quotient (THQ) and hazard index (HI) values were below one for all samples, suggesting no non-carcinogenic risk to consumers.

Distribution and health risk assessment of heavy metals in road dust from an industrial estate in Trinidad, West Indies.

Road dust from the Point Lisas Industrial Estate in Trinidad, West Indies was investigated to determine its heavy metal content and the associated health risks. The average concentrations of Cd, Cr, Cu, Mn, Ni, Pb and Zn were 3.44, 37.69, 58.16, 770.69, 35.61, 68.50 and 342.53 µg/g, respectively. The health risks due to exposure to heavy metals in road dust were assessed based on the US EPA's Health Risk Assessment Model for both carcinogenic and non-carcinogenic effects. The health risk assessment indicated that the ingestion pathway was the main exposure route to heavy metals from road dust; however, HI values suggested no potential health risks to both children and adults. The cancer risks for Cd, Cr and Ni were less than 10-6 and the resulting exposure was therefore considered low.

GC-MS analysis of the bioactive phytoconstituents of various organic crude extracts from the seed kernels of Manilkara bidentata (balata) collected in Trinidad, W.I.

The present study reports the first phytochemical investigation of the seed kernels of Manilkara bidentata (Balata) harvested in Trinidad, W.I. Gas chromatography-mass spectrometry (GC-MS) analysis of the n-hexane, chloroform, ethyl acetate, ethanol and methanol extracts showed a total of 39 components. 2,6,10,14,18-pentamethyl-2,6,10,14,18-eicosapentaene (74.93%), 9-octadecenoic acid, (Z)- 2,3-dihydroxypropyl ester (79.98%), (Z)-ethyl oleate (92.75%), Z,E-2-methyl-3,13-octadecadien-1-ol (80.51%) and 5-(hydroxymethyl)-2-furancarboxyaldehyde (50.32%) were the major constituents identified in the n-hexane, chloroform, ethyl acetate, ethanol and methanol extracts, respectively. The extracts showed the presence of several bioactive components and provides reference data for further research of its active constituents.

A preliminary assessment of heavy metals in sediments from the Cipero and South Oropouche Rivers in Trinidad, West Indies.

The increasing urbanization and industrial processes in Trinidad within recent years could pose a possible contamination threat to the aquatic environment. The southwestern part of the island houses numerous industrial activities, and the recent sightings of schools of dead fish and other marine organisms in that locality is cause for concern prompting research into this occurrence. Sediment and surface water samples from the Cipero and South Oropouche Rivers in South Trinidad were analyzed for their heavy metal content (Cd, Cr, Cu, Mn, Ni, Pb, and Zn). Another watercourse, the Moruga River, was selected as a control, based on its location away from significant anthropogenic sources, and the levels of heavy metals obtained for this location were considered as background concentrations for both surface waters and sediments. Cadmium, Ni, and Pb were not detected in surface water samples of both rivers. The corresponding order of metals in the Cipero River was Mn > Cr > Zn > Cu, while for the South Oropouche River, the order was Mn > Cr > Cu > Zn. The individual concentrations of metals in sediments found in the Cipero and South Oropouche Rivers varied according to the following orders: Mn > Zn > Cu > Pb > Ni > Cr > Cd and Mn > Zn > Pb > Cu > Ni > Cr > Cd, respectively. Assessments of the pollution status in sediments revealed that the Cipero River was considered polluted with a moderate degree of ecological pollution while the South Oropouche River was also deemed polluted; however, the degree of ecological pollution associated with that river was low. Principal component analysis (PCA) and cluster analysis (CA) confirmed that both anthropogenic and natural sources contributed to heavy metal contamination in sediments of both rivers.