There is a need for rapid assessment techniques for the determination of environmental contamination. Traditionally, faecal pollution in Trinidad and Tobago is assessed on the basis of concentrations of bacterial indicator organisms such as Enterococcus spp. and E.coli. Faecal-indicator bacterial concentrations have been measured using culture-based methods such as membrane filtration which are slow and require long hours of preparation and analysis. The need for rapid, reliable tests for recreational water quality is of great importance to protect public health in a timely manner. In 2016, Colilert 18 which uses Defined Substrate Technology® (DST®) nutrient indicators ONPG and MUG to detect coliforms and E. coli was used to monitor water quality at sites in Trinidad and Tobago. Coliforms use their β-galactosidase enzyme to metabolize ONPG and change it from colorless to yellow giving results in 24 hours. In 2017, the project was completed with both wet and dry season analysis done at two popular bathing sites in Trinidad- Maracas Beach and Chaguaramas Peninsula. Preliminary results indicated the IDEXX can be used as a rapid indicator test, but results varied in heavily polluted waters when the IDEXX MPN maximum value is reached.
April 14, 2018