Tese
Resíduos de pesticidas e compostos perfluorados em águas: avaliação da exposição da população atráves do consumo
Fecha
2015-12-04Autor
Schwanz, Thiago Guilherme
Institución
Resumen
Contamination of water resources has been caused great impact to the environment.
The water constitutes the greatest source of food, and its value for health is
incalculable. Despite this, the presence of contaminants in water for consumption in
Brazil is a topic with few researches and sources of information. The main
contamination of drinking water takes place directly by man, by the abusive use of
pesticides or environmental contaminants, with high bioaccumulation potential in the
environment, such as perfluorinated and organochlorine compounds. These
compounds are present in water in trace levels, and appropriate analytical methods
in order to demonstrate the suitability of method, ensuring the reliability of the results
are needed. This study presents two multi-residue methods for determination of
perfluorinated compounds (PFCs) and for the determination of pesticides in samples
of tap water, bottled water and groundwater collected in Brazil, Spain and France.
For PFCs was used solid phase extraction automated "in line" method with direct
injection of the sample coupled to mass spectrometry with detection limits between
0.15 and 8.76 ng/L, and the determination of pesticides has been carried out by solid
phase extraction and analysed using different techniques of separation and ionization
LC-ESI-MS/MS, GC-MS/EI and GC-MS/NCI, with detection limits between 1.02 and
48.21 ng/L. The obtained results showed that the tap water have high concentrations
of PFCs, especially in Brazil, with an average of 15.83 ng/L, followed by Spain and
France with 15.33 and 7.73 ng/L, respectively. For pesticide analyzes, the data found
demonstrate that the groundwater obtained in Brazil showed the highest
concentrations of investigated contaminants in comparison with tap and bottled
water. Regarding the risk of exposure by ingestion through drinking water, PFCs
represent greater danger (estimated at 54.8, 58.0 and 75.6 ng/person per day in
Spain, France and Brazil) in relation to pesticides (10.23, 29.40, 30.11 ng/person per
day in Spain, France and Brazil, respectively). However, despite the levels found in
the investigated countries, the consumption of drinking water does not poses
imminent risks to contamination associated with PFCs and pesticides.