Laboratory of Tracers - LT




The Laboratory of Tracers (LT), established since 1972, is pioneer in Brazil in the use of fluorescent dyes as inactive tracers, an alternative to artificial radioactive tracers. Besides researches and studies on Surface Water Hydrology, the Laboratory of Tracers was one of the first of COPPE/UFRJ laboratories to approach experimentally Environment related problems.

In partnership with the University of Texas (Austin), LT developed methodologies to use fluorescent tracers associated to inert gaseous tracers aiming to study surface water aeration process.

LT uses techniques employing fluorescent tracers in studies aiming to evaluate the dispersion of domestic and industrial effluents that are discharged in receiver bodies (rivers, lakes, and coastal waters) with the support of the Institut für Hydrologie–GSF (Munich).

                    Samples of fluorescent tracers                                                     Tracer injection

Regarding sewage submarine outfalls, LT has worked in partnership with the research line on Coastal Engineering to measure “in situ” dispersion plumes of the fluorescent tracer continuously injected in the outfall pipe.

Dispersion plumes measured at the field are used to calibrate computational model simulations particularly SisBAHIA® model (  Several articles were published in partnership wit the Georgia Institute of Technology (Atlanta).
                                                                       Tracer plume at the sea

                                                             Boat for fluorescent tracer monitoring at the sea 

Frequently LT interacts with other research lines from the Civil Engineering Program and the Ocean Engineering Program aiming at modeling water quality and collaborates with the Laboratory of Pollution Control of the Chemical Engineering Program at COPPE/UFRJ in inactive tracer use in biological reactor activities.

Current LT activities are concentrated on fluorescent tracer applications on surface hydrology and the study of problems related to water pollution.
Typical applications are:

• Determination of pollutant dispersion coefficient on rivers and lakes
Evaluation of submarine outfall pipe efficiency on rivers and coastal waters
Natural reareation capability characterization on rivers and channels
Measure of hydrodynamic parameters on sewage treatment plants
Turbinated flow measure on medium and large hydroelectric power plants
Meteo-oceanographic parameter monitoring (in general as a support to fluorescent tracer activities)

                                                                        Meteorological Station Assembly

Special attention is given to laboratory determination of aqueous sample fluorescence through “Synchronous Scan Method”.

In recent years, LT has developed projects and constructed field equipments that are not encountered in the market but are fundamental to improve the use of fluorescent tracers.

The Laboratory of Tracers is one of the newest members of the Ecosystem Maintenance and Recovery and Impact Area Remediation Network.



Currently, the Laboratory of Tracers occupies a 300 m2area at the back of UFRJ Technological Center, Block I.

Current facilities include secretary’s office, laboratory of chemistry, laboratory of electronics, faculty room, equipment room, computer room, machine workshop and bathrooms.

LT owns the following laboratory and field equipment:

Laboratory equipment -  Shimadzu RF-5301 spectrofluorimeter (1);  field equipment -  Turner T-10 field fluorimeter (3),  Turner SCUFA submersible fluorimeter (1),  300 kHz acoustic current profiler  (ADCP) (2),  600 kHz wave and current acoustic profiler (ADCP) (1), 1200 kHz acoustic current profiler  (ADCP)  (1), Manning automatic water sample collector (1),  Campbell Scientific meteorological station (3), CTD Seabird (2), GlobalWater flowmeter(4); and support equipment – inflatable power boat (1), truck (1) and trailer  (1). 




João Sérgio Fajardo Roldão, M.Sc. - COPPE/UFRJ (head of the department)
José Otavio Goulart Pecly, D.Sc. - COPPE/UFRJ



Technicians and administrative staff

Amauri Cavalcanti de Lima
Renato Burgo Lopes 
Henrique Costa de Mattos